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* [PATCH 00/17] libtracefs: Introducing tracefs_sql() to create synthetice events with an SQL line
@ 2021-07-30 22:18 Steven Rostedt
  2021-07-30 22:18 ` [PATCH 01/17] libtracefs: Added new API tracefs_sql() Steven Rostedt
                   ` (17 more replies)
  0 siblings, 18 replies; 26+ messages in thread
From: Steven Rostedt @ 2021-07-30 22:18 UTC (permalink / raw)
  To: linux-trace-devel
  Cc: linux-kernel, Tom Zanussi, Daniel Bristot de Oliveira,
	Masami Hiramatsu, Namhyung Kim, linux-rt-users, Clark Williams,
	Steven Rostedt (VMware)

From: "Steven Rostedt (VMware)" <rostedt@goodmis.org>

This patch set depends on:

   https://patchwork.kernel.org/project/linux-trace-devel/list/?series=523775

Below is from the man page, which has a fully functional parser as its
example (in man page, not here. But the usage of that parser is described in
the FUNCTIONAL EXAMPLE section below).

struct tracefs_synth *tracefs_sql(struct tep_handle *tep, const char *name,
				  const char *sql_buffer, char **err);

Synthetic events are dynamically created events that attach two existing events
together via one or more matching fields between the two events. It can be used
to find the latency between the events, or to simply pass fields of the first event
on to the second event to display as one event.

The Linux kernel interface to create synthetic events is complex, and there needs
to be a better way to create synthetic events that is easy and can be understood
via existing technology.

If you think of each event as a table, where the fields are the column of the table
and each instance of the event as a row, you can understand how SQL can be used
to attach two events together and for another event (table). Utilizing the
SQL *SELECT* *FROM* *JOIN* *ON* [ *WHERE* ] syntax, a synthetic event can easily
be created from two different events.


*tracefs_sql*() takes in a *tep* handler (See _tep_local_events_(3)) that is used to
verify the events within the _sql_buffer_ expression. The _name_ is the name of the
synthetic event to create. If _err_ points to an address of a string, it will be filled
with a detailed message on any type of parsing error, including fields that do not belong
to an event, or if the events or fields are not properly compared.

The man page contains a fully functional parser where it will create a synthetic
event from a SQL syntax passed in via the command line or a file. 

The SQL format is as follows:

*SELECT* <fields> FROM <start-event> JOIN <end-event> ON <matching-fields> WHERE <filter>

Note, although the examples show the SQL commands in uppercase, they are not required to
be so. That is, you can use "SELECT" or "select" or "sElEct".

For example:
[source,c]
--
SELECT syscalls.sys_enter_read.fd, syscalls.sys_exit_read.ret FROM syscalls.sys_enter_read
   JOIN syscalls.sys_exit_read
   ON syscalls.sys_enter_read.common_pid = syscalls.sys_exit_write.common_pid
--

Will create a synthetic event that with the fields:

  u64 fd; s64 ret;

Because the function takes a _tep_ handle, and usually all event names are unique, you can
leave off the system (group) name of the event, and *tracefs_sql*() will discover the
system for you.

That is, the above statement would work with:

[source,c]
--
SELECT sys_enter_read.fd, sys_exit_read.ret FROM sys_enter_read JOIN sys_exit_read
   ON sys_enter_read.common_pid = sys_exit_write.common_pid
--

The *AS* keyword can be used to name the fields as well as to give an alias to the
events, such that the above can be simplified even more as:

[source,c]
--
SELECT start.fd, end.ret FROM sys_enter_read AS start JOIN sys_exit_read AS end ON start.common_pid = end.common_pid
--

The above aliases _sys_enter_read_ as *start* and _sys_exit_read_ as *end* and uses
those aliases to reference the event throughout the statement.

Using the *AS* keyword in the selection portion of the SQL statement will define what
those fields will be called in the synthetic event.

[source,c]
--
SELECT start.fd AS filed, end.ret AS return FROM sys_enter_read AS start JOIN sys_exit_read AS end
   ON start.common_pid = end.common_pid
--

The above labels the _fd_ of _start_ as *filed* and the _ret_ of _end_ as *return* where
the synthetic event that is created will now have the fields:

  u64 filed; s64 return;

The fields can also be calculated with results passed to the synthetic event:

[source,c]
--
select start.truesize, end.len, (start.truesize - end.len) as diff from napi_gro_receive_entry as start
   JOIN netif_receive_skb as end ON start.skbaddr = end.skbaddr
--

Which would show the *truesize" of the _napi_gro_receive_entry_ event, the actual
_len_ of the content, shown by the _netif_receive_skb_, and also the delta between
the two and expressed by the field *diff*.

The code also supports recording the timestamps at either event, and performing calculations
on them. For wakeup latency, you have:

[source,c]
--
select start.pid, (end.TIMESTAMP_USECS - start.TIMESTAMP_USECS) as lat from sched_waking as start
   JOIN sched_switch as end ON start.pid = end.next_pid
--

The above will create a synthetic event that records the _pid_ of the task being woken up,
and the time difference between the _sched_waking_ event and the _sched_switch_ event.
The *TIMESTAMP_USECS* will truncate the time down to microseconds as the timestamp usually
recorded in the tracing buffer has nanosecond resolution. If you do not want that
truncation, use *TIMESTAMP* instead of *TIMESTAMP_USECS*.

Finally, the *WHERE* clause can be added, that will let you add filters on either or both events.

[source,c]
--
select start.pid, (end.TIMESTAMP_USECS - start.TIMESTAMP_USECS) as lat from sched_waking as start
   JOIN sched_switch as end ON start.pid = end.next_pid
   WHERE start.prio < 100 && (!(end.prev_pid < 1 || end.prev_prio > 100) || end.prev_pid == 0)
--

*NOTE*

Although both events can be used together in the *WHERE* clause, they must not be mixed outside
the top most "&&" statements. You can not OR (||) the events together, where a filter of one
event is OR'd to a filter of the other event. This does not make sense, as the synthetic event
requires both events to take place to be recorded. If one is filtered out, then the synthetic
event does not execute.

[source,c]
--
select start.pid, (end.TIMESTAMP_USECS - start.TIMESTAMP_USECS) as lat from sched_waking as start
   JOIN sched_switch as end ON start.pid = end.next_pid
   WHERE start.prio < 100 && end.prev_prio < 100
--

The above is valid.

Where as the below is not.

[source,c]
--
select start.pid, (end.TIMESTAMP_USECS - start.TIMESTAMP_USECS) as lat from sched_waking as start
   JOIN sched_switch as end ON start.pid = end.next_pid
   WHERE start.prio < 100 || end.prev_prio < 100
--

Returns 0 on success and -1 on failure. On failure, if _err_ is defined, it will be
allocated to hold a detailed description of what went wrong if it the error was caused
by a parsing error, or that an event, field does not exist or is not compatible with
what it was combined with.

FUNCTIONAL EXAMPLE:
-------------------

After applying this patch, and installing it. If you compile the example from the man
page (calling it sqlhist.c):

 >$ gcc -o sqlhist sqlhist.c `pkg-config --cflags --libs libtracefs`
 >$ su
 ># ./sqlhist -n syscall_wait -e 'select start.id, (end.TIMESTAMP_USECS - start.TIMESTAMP_USECS) as lat
    from sys_enter as start join sys_exit as end on start.common_pid = end.common_pid
    where start.id != 23 && start.id != 7 && start.id != 61 && start.id != 230 &&
          start.id != 232 && start.id != 270 && start.id != 271 && start.id != 202'


(All the start.id filtering is hiding the syscalls that block for a long time)

 ># echo 'hist:keys=id.syscall,lat.buckets=10:sort=lat' > /sys/kernel/tracing/events/synthetic/syscall_wait/trigger

<wait a while>

 ># cat /sys/kernel/tracing/events/synthetic/syscall_wait/hist
 # event histogram
 #
 # trigger info: hist:keys=id.syscall,lat.buckets=10:vals=hitcount:sort=lat.buckets=10:size=2048 [active]
 #

{ id: sys_fadvise64                 [221], lat: ~ 0-9 } hitcount:          1
{ id: sys_fcntl                     [ 72], lat: ~ 0-9 } hitcount:          5
{ id: sys_read                      [  0], lat: ~ 0-9 } hitcount:         51
{ id: sys_dup2                      [ 33], lat: ~ 0-9 } hitcount:          1
{ id: sys_newfstat                  [  5], lat: ~ 0-9 } hitcount:          7
{ id: sys_getpid                    [ 39], lat: ~ 0-9 } hitcount:         18
{ id: sys_openat                    [257], lat: ~ 0-9 } hitcount:          3
{ id: sys_newstat                   [  4], lat: ~ 0-9 } hitcount:         22
{ id: sys_newlstat                  [  6], lat: ~ 0-9 } hitcount:         44
{ id: sys_write                     [  1], lat: ~ 0-9 } hitcount:         23
{ id: sys_brk                       [ 12], lat: ~ 0-9 } hitcount:          4
{ id: sys_readlink                  [ 89], lat: ~ 0-9 } hitcount:         11
{ id: sys_close                     [  3], lat: ~ 0-9 } hitcount:         21
{ id: sys_mprotect                  [ 10], lat: ~ 0-9 } hitcount:          4
{ id: sys_arch_prctl                [158], lat: ~ 0-9 } hitcount:          2
{ id: sys_getuid                    [102], lat: ~ 0-9 } hitcount:         12
{ id: sys_rt_sigaction              [ 13], lat: ~ 0-9 } hitcount:        105
{ id: sys_statfs                    [137], lat: ~ 0-9 } hitcount:          8
{ id: sys_rt_sigprocmask            [ 14], lat: ~ 0-9 } hitcount:        121
{ id: sys_inotify_add_watch         [254], lat: ~ 0-9 } hitcount:          7
{ id: sys_mmap                      [  9], lat: ~ 0-9 } hitcount:         10
{ id: sys_ioctl                     [ 16], lat: ~ 0-9 } hitcount:         32
{ id: sys_pread64                   [ 17], lat: ~ 0-9 } hitcount:          4
{ id: sys_setpgid                   [109], lat: ~ 0-9 } hitcount:          2
{ id: sys_lseek                     [  8], lat: ~ 0-9 } hitcount:         11
{ id: sys_access                    [ 21], lat: ~ 0-9 } hitcount:          1
{ id: sys_rt_sigprocmask            [ 14], lat: ~ 10-19 } hitcount:          9
{ id: sys_munmap                    [ 11], lat: ~ 10-19 } hitcount:          1
{ id: sys_newstat                   [  4], lat: ~ 10-19 } hitcount:          1
{ id: sys_rt_sigaction              [ 13], lat: ~ 10-19 } hitcount:          1
{ id: sys_read                      [  0], lat: ~ 10-19 } hitcount:         11
{ id: sys_openat                    [257], lat: ~ 10-19 } hitcount:         13
{ id: sys_getpid                    [ 39], lat: ~ 10-19 } hitcount:          1
{ id: sys_inotify_add_watch         [254], lat: ~ 10-19 } hitcount:          2
{ id: sys_write                     [  1], lat: ~ 10-19 } hitcount:         10
{ id: sys_read                      [  0], lat: ~ 20-29 } hitcount:          4
{ id: sys_pipe                      [ 22], lat: ~ 20-29 } hitcount:          1
{ id: sys_write                     [  1], lat: ~ 20-29 } hitcount:         11
{ id: sys_write                     [  1], lat: ~ 30-39 } hitcount:          2
{ id: sys_inotify_add_watch         [254], lat: ~ 30-39 } hitcount:          1
{ id: sys_write                     [  1], lat: ~ 40-49 } hitcount:          1
{ id: sys_inotify_add_watch         [254], lat: ~ 40-49 } hitcount:          1
{ id: sys_openat                    [257], lat: ~ 40-49 } hitcount:          1
{ id: sys_read                      [  0], lat: ~ 70-79 } hitcount:          8
{ id: sys_read                      [  0], lat: ~ 80-89 } hitcount:          1
{ id: sys_read                      [  0], lat: ~ 110-119 } hitcount:          2
{ id: sys_clone                     [ 56], lat: ~ 240-249 } hitcount:          1
{ id: sys_execve                    [ 59], lat: ~ 350-359 } hitcount:          1
{ id: sys_write                     [  1], lat: ~ 1960-1969 } hitcount:          1

Totals:
    Hits: 615
    Entries: 49
    Dropped: 0


Steven Rostedt (VMware) (17):
  libtracefs: Added new API tracefs_sql()
  tracefs: Add unit tests for tracefs_sql()
  libtracefs: Add comparing start and end fields in tracefs_sql()
  libtracefs: Add unit test to test tracefs_sql() compare
  libtracefs: Add filtering for start and end events in tracefs_sql()
  libtracefs: Add unit test to test tracefs_sql() where clause
  libtracefs: Make sqlhist parser reentrant
  libtracefs: Make parser unique to libtracefs
  libtracefs: Add line number and index to expr structure
  libtracefs: Add a parse_error() helper function to record errors
  libtracefs: Add error message when match fields are not FROM and JOIN
    events
  libtracefs: Add error message when match or init fails from bad events
  libtracefs; Add error message for bad selections to SQL sequence
  libtracefs: Add error message when compare fields fail
  libtracefs: Add error message for grouping events in SQL filter
  libtracefs: Add error message for bad filters in SQL statement
  libtracefs: Add man page for tracefs_sql()

 Documentation/libtracefs-sql.txt |  367 +++++++++
 include/tracefs.h                |    3 +
 src/Makefile                     |   11 +
 src/sqlhist-parse.h              |   75 ++
 src/sqlhist.l                    |   95 +++
 src/sqlhist.y                    |  241 ++++++
 src/tracefs-sqlhist.c            | 1310 ++++++++++++++++++++++++++++++
 utest/tracefs-utest.c            |   78 ++
 8 files changed, 2180 insertions(+)
 create mode 100644 Documentation/libtracefs-sql.txt
 create mode 100644 src/sqlhist-parse.h
 create mode 100644 src/sqlhist.l
 create mode 100644 src/sqlhist.y
 create mode 100644 src/tracefs-sqlhist.c

-- 
2.30.2


^ permalink raw reply	[flat|nested] 26+ messages in thread

* [PATCH 01/17] libtracefs: Added new API tracefs_sql()
  2021-07-30 22:18 [PATCH 00/17] libtracefs: Introducing tracefs_sql() to create synthetice events with an SQL line Steven Rostedt
@ 2021-07-30 22:18 ` Steven Rostedt
  2021-08-01  6:32   ` Ahmed S. Darwish
  2021-08-02 23:45   ` Namhyung Kim
  2021-07-30 22:18 ` [PATCH 02/17] tracefs: Add unit tests for tracefs_sql() Steven Rostedt
                   ` (16 subsequent siblings)
  17 siblings, 2 replies; 26+ messages in thread
From: Steven Rostedt @ 2021-07-30 22:18 UTC (permalink / raw)
  To: linux-trace-devel
  Cc: linux-kernel, Tom Zanussi, Daniel Bristot de Oliveira,
	Masami Hiramatsu, Namhyung Kim, linux-rt-users, Clark Williams,
	Steven Rostedt (VMware)

From: "Steven Rostedt (VMware)" <rostedt@goodmis.org>

This adds the API tracefs_sql() that takes a tep_handle handler, a name,
and a SQL string and parses it to produce a tracefs_synth synthetic event
handler.

Currently it only supports simple SQL of the type:

  SELECT start.common_pid AS pid, end.common_timestamp.usecs AS usecs
    FROM sched_waking AS start on sched_switch AS end
    ON start.pid = end.next_pid

Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
---
 include/tracefs.h     |   3 +
 src/Makefile          |  11 +
 src/sqlhist-parse.h   |  69 +++++
 src/sqlhist.l         |  88 ++++++
 src/sqlhist.y         | 143 +++++++++
 src/tracefs-sqlhist.c | 691 ++++++++++++++++++++++++++++++++++++++++++
 6 files changed, 1005 insertions(+)
 create mode 100644 src/sqlhist-parse.h
 create mode 100644 src/sqlhist.l
 create mode 100644 src/sqlhist.y
 create mode 100644 src/tracefs-sqlhist.c

diff --git a/include/tracefs.h b/include/tracefs.h
index 246647f6496d..3d83604031b1 100644
--- a/include/tracefs.h
+++ b/include/tracefs.h
@@ -385,4 +385,7 @@ void tracefs_synth_free(struct tracefs_synth *synth);
 int tracefs_synth_show(struct trace_seq *seq, struct tracefs_instance *instance,
 		       struct tracefs_synth *synth);
 
+struct tracefs_synth *tracefs_sql(struct tep_handle *tep, const char *name,
+				  const char *sql_buffer, char **err);
+
 #endif /* _TRACE_FS_H */
diff --git a/src/Makefile b/src/Makefile
index 767af49034ee..eac404a1a147 100644
--- a/src/Makefile
+++ b/src/Makefile
@@ -12,6 +12,11 @@ OBJS += tracefs-kprobes.o
 OBJS += tracefs-hist.o
 OBJS += tracefs-filter.o
 
+# Order matters for the the three below
+OBJS += sqlhist-lex.o
+OBJS += sqlhist.tab.o
+OBJS += tracefs-sqlhist.o
+
 OBJS := $(OBJS:%.o=$(bdir)/%.o)
 DEPS := $(OBJS:$(bdir)/%.o=$(bdir)/.%.d)
 
@@ -32,6 +37,12 @@ $(LIBTRACEFS_SHARED_SO): $(LIBTRACEFS_SHARED_VERSION)
 
 libtracefs.so: $(LIBTRACEFS_SHARED_SO)
 
+sqlhist.tab.c: sqlhist.y
+	bison --debug -v --report-file=bison.report -d -o $@ $^
+
+sqlhist-lex.c: sqlhist.l sqlhist.tab.c
+	flex -o $@ $<
+
 $(bdir)/%.o: %.c
 	$(Q)$(call do_fpic_compile)
 
diff --git a/src/sqlhist-parse.h b/src/sqlhist-parse.h
new file mode 100644
index 000000000000..aa5232eea451
--- /dev/null
+++ b/src/sqlhist-parse.h
@@ -0,0 +1,69 @@
+#ifndef __SQLHIST_PARSE_H
+#define __SQLHIST_PARSE_H
+
+#include <stdarg.h>
+#include <tracefs.h>
+
+struct str_hash;
+#define HASH_BITS 10
+
+struct sql_table;
+
+struct sqlhist_bison {
+	const char		*buffer;
+	size_t			buffer_size;
+	size_t			buffer_idx;
+	int			line_no;
+	int			line_idx;
+	struct sql_table	*table;
+	char			*parse_error_str;
+	struct str_hash         *str_hash[1 << HASH_BITS];
+};
+
+extern struct sqlhist_bison *sb;
+
+#include "sqlhist.tab.h"
+
+enum filter_type {
+	FILTER_GROUP,
+	FILTER_NOT_GROUP,
+	FILTER_EQ,
+	FILTER_NE,
+	FILTER_LE,
+	FILTER_LT,
+	FILTER_GE,
+	FILTER_GT,
+	FILTER_BIN_AND,
+	FILTER_STR_CMP,
+	FILTER_AND,
+	FILTER_OR,
+};
+
+enum compare_type {
+	COMPARE_GROUP,
+	COMPARE_ADD,
+	COMPARE_SUB,
+	COMPARE_MUL,
+	COMPARE_DIV,
+	COMPARE_BIN_AND,
+	COMPARE_BIN_OR,
+	COMPARE_AND,
+	COMPARE_OR,
+};
+
+char * store_str(struct sqlhist_bison *sb, const char *str);
+
+int table_start(struct sqlhist_bison *sb);
+
+void *add_field(struct sqlhist_bison *sb, const char *field, const char *label);
+
+int add_match(struct sqlhist_bison *sb, void *A, void *B);
+
+int add_selection(struct sqlhist_bison *sb, void *item, const char *label);
+int add_from(struct sqlhist_bison *sb, void *item);
+int add_to(struct sqlhist_bison *sb, void *item);
+
+extern void sql_parse_error(struct sqlhist_bison *sb, const char *text,
+			    const char *fmt, va_list ap);
+
+#endif
diff --git a/src/sqlhist.l b/src/sqlhist.l
new file mode 100644
index 000000000000..3f394f37b738
--- /dev/null
+++ b/src/sqlhist.l
@@ -0,0 +1,88 @@
+%{
+/* code here */
+
+#include <stdarg.h>
+#include "sqlhist-parse.h"
+
+extern int my_yyinput(char *buf, int max);
+
+#undef YY_INPUT
+#define YY_INPUT(b, r, m) ({r = my_yyinput(b, m);})
+
+#define YY_NO_INPUT
+#define YY_NO_UNPUT
+
+#define YY_EXTRA_TYPE struct sqlhist_bison *
+
+#define HANDLE_COLUMN do { sb->line_idx += strlen(yytext); } while (0)
+
+%}
+
+%option caseless
+
+field		[a-z_][a-z0-9_\.]*
+qstring		\"[^\"]*\"
+hexnum		0x[0-9a-z]+
+number		[0-9a-z]+
+
+%%
+
+select { HANDLE_COLUMN; return SELECT; }
+as { HANDLE_COLUMN; return AS; }
+from { HANDLE_COLUMN; return FROM; }
+join { HANDLE_COLUMN; return JOIN; }
+on { HANDLE_COLUMN; return ON; }
+
+{qstring} {
+	HANDLE_COLUMN;
+	yylval.string = store_str(sb, yytext);
+	return STRING;
+}
+
+{field} {
+	HANDLE_COLUMN;
+	yylval.string = store_str(sb, yytext);
+	return FIELD;
+}
+
+{hexnum} {
+	HANDLE_COLUMN;
+	yylval.number = strtol(yytext, NULL, 0);
+	return NUMBER;
+}
+
+{number} {
+	HANDLE_COLUMN;
+	yylval.number = strtol(yytext, NULL, 0);
+	return NUMBER;
+}
+
+\!= { HANDLE_COLUMN; return NEQ; }
+\<= { HANDLE_COLUMN; return LE; }
+\>= { HANDLE_COLUMN; return GE; }
+== { HANDLE_COLUMN; return EQ; }
+&& { HANDLE_COLUMN; return AND; }
+"||" { HANDLE_COLUMN; return OR; }
+[<>&~] { HANDLE_COLUMN; return yytext[0]; }
+
+[\!()\-\+\*/,=] { HANDLE_COLUMN; return yytext[0]; }
+
+[ \t] { HANDLE_COLUMN; }
+\n { sb->line_idx = 0; sb->line_no++; }
+
+. { HANDLE_COLUMN; return PARSE_ERROR; }
+%%
+
+int yywrap(void)
+{
+	return 1;
+}
+
+void yyerror(const char *fmt, ...)
+{
+	va_list ap;
+
+	va_start(ap, fmt);
+	sql_parse_error(sb, yytext, fmt, ap);
+	va_end(ap);
+}
diff --git a/src/sqlhist.y b/src/sqlhist.y
new file mode 100644
index 000000000000..ecb0a0ed44b3
--- /dev/null
+++ b/src/sqlhist.y
@@ -0,0 +1,143 @@
+%{
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <errno.h>
+
+#include "sqlhist-parse.h"
+
+extern int yylex(void);
+extern void yyerror(char *fmt, ...);
+
+#define CHECK_RETURN_PTR(x)					\
+	do {							\
+		if (!(x)) {					\
+			printf("FAILED MEMORY: %s\n", #x);	\
+			return -ENOMEM;				\
+		}						\
+	} while (0)
+
+#define CHECK_RETURN_VAL(x)					\
+	do {							\
+		if ((x) < 0) {					\
+			printf("FAILED MEMORY: %s\n", #x);	\
+			return -ENOMEM;				\
+		}						\
+	} while (0)
+
+%}
+
+%union {
+	int	s32;
+	char	*string;
+	long	number;
+	void	*expr;
+}
+
+%token AS SELECT FROM JOIN ON PARSE_ERROR
+%token <number> NUMBER
+%token <string> STRING
+%token <string> FIELD
+%token <string> LE GE EQ NEQ AND OR
+
+%left '+' '-'
+%left '*' '/'
+%left '<' '>'
+%left AND OR
+
+%type <string> name label
+
+%type <expr>  selection_expr field item named_field join_clause
+
+%%
+
+start :
+   select_statement
+ ;
+
+label : AS name { CHECK_RETURN_PTR($$ = store_str(sb, $2)); }
+ | name { CHECK_RETURN_PTR($$ = store_str(sb, $1)); }
+ ;
+
+select : SELECT  { table_start(sb); }
+  ;
+
+select_statement :
+    select selection_list table_exp
+  ;
+
+selection_list :
+   selection
+ | selection ',' selection_list
+ ;
+
+selection :
+    selection_expr
+				{
+					CHECK_RETURN_VAL(add_selection(sb, $1, NULL));
+				}
+  | selection_expr label
+				{
+					CHECK_RETURN_VAL(add_selection(sb, $1, $2));
+				}
+  ;
+
+selection_expr :
+   field
+ | '(' field ')'		{  $$ = $2; }
+ ;
+
+item :
+   named_field
+ | field
+ ;
+
+field :
+   FIELD	{ $$ = add_field(sb, $1, NULL); CHECK_RETURN_PTR($$); }
+ ;
+
+named_field :
+   FIELD label { $$ = add_field(sb, $1, $2); CHECK_RETURN_PTR($$); }
+ ;
+
+name :
+   FIELD
+ ;
+
+table_exp :
+   from_clause join_clause
+ ;
+
+from_clause :
+   FROM item		{ CHECK_RETURN_VAL(add_from(sb, $2)); }
+
+/*
+ * Select from a from clause confuses the variable parsing.
+ * disable it for now.
+
+   | FROM '(' select_statement ')' label
+				{
+					from_table_end($5);
+					$$ = store_printf("FROM (%s) AS %s", $3, $5);
+				}
+*/
+ ;
+
+join_clause :
+  JOIN item ON match_clause	{ add_to(sb, $2); }
+ ;
+
+match :
+   item '=' item { CHECK_RETURN_VAL(add_match(sb, $1, $3)); }
+ | item EQ item { CHECK_RETURN_VAL(add_match(sb, $1, $3)); }
+
+ ;
+
+match_clause :
+   match
+ | match ',' match_clause
+ ;
+
+%%
+
+
diff --git a/src/tracefs-sqlhist.c b/src/tracefs-sqlhist.c
new file mode 100644
index 000000000000..7ec0c11b902e
--- /dev/null
+++ b/src/tracefs-sqlhist.c
@@ -0,0 +1,691 @@
+// SPDX-License-Identifier: LGPL-2.1
+/*
+ * Copyright (C) 2021 VMware Inc, Steven Rostedt <rostedt@goodmis.org>
+ *
+ * Updates:
+ * Copyright (C) 2021, VMware, Tzvetomir Stoyanov <tz.stoyanov@gmail.com>
+ *
+ */
+#include <trace-seq.h>
+#include <stdlib.h>
+#include <errno.h>
+
+#include "tracefs.h"
+#include "tracefs-local.h"
+#include "sqlhist-parse.h"
+
+struct sqlhist_bison *sb;
+
+extern int yylex_init(void* ptr_yy_globals);
+extern int yylex_init_extra(struct sqlhist_bison *sb, void* ptr_yy_globals);
+extern int yylex_destroy (void * yyscanner );
+
+struct str_hash {
+	struct str_hash		*next;
+	char			*str;
+};
+
+enum alias_type {
+	ALIAS_EVENT,
+	ALIAS_FIELD,
+};
+
+#define for_each_field(expr, field, table) \
+	for (expr = (table)->fields; expr; expr = (field)->next)
+
+struct field {
+	struct expr		*next;	/* private link list */
+	const char		*system;
+	const char		*event;
+	const char		*raw;
+	const char		*label;
+	const char		*field;
+};
+
+struct match {
+	struct match		*next;
+	struct expr		*lval;
+	struct expr		*rval;
+};
+
+enum expr_type
+{
+	EXPR_NUMBER,
+	EXPR_STRING,
+	EXPR_FIELD,
+};
+
+struct expr {
+	struct expr		*free_list;
+	struct expr		*next;
+	enum expr_type		type;
+	union {
+		struct field	field;
+		const char	*string;
+		long		number;
+	};
+};
+
+struct sql_table {
+	struct sqlhist_bison	*sb;
+	const char		*name;
+	struct expr		*exprs;
+	struct expr		*fields;
+	struct expr		*from;
+	struct expr		*to;
+	struct match		*matches;
+	struct match		**next_match;
+	struct expr		*selections;
+	struct expr		**next_selection;
+};
+
+__hidden int my_yyinput(char *buf, int max)
+{
+	if (!sb || !sb->buffer)
+		return -1;
+
+	if (sb->buffer_idx + max > sb->buffer_size)
+		max = sb->buffer_size - sb->buffer_idx;
+
+	if (max)
+		memcpy(buf, sb->buffer + sb->buffer_idx, max);
+
+	sb->buffer_idx += max;
+
+	return max;
+}
+
+__hidden void sql_parse_error(struct sqlhist_bison *sb, const char *text,
+			      const char *fmt, va_list ap)
+{
+	const char *buffer = sb->buffer;
+	struct trace_seq s;
+	int line = sb->line_no;
+	int idx = sb->line_idx - strlen(text);
+	int i;
+
+	if (!buffer)
+		return;
+
+	trace_seq_init(&s);
+	if (!s.buffer) {
+		fprintf(stderr, "Error allocating internal buffer\n");
+		return;
+	}
+
+	for (i = 0; line && buffer[i]; i++) {
+		if (buffer[i] == '\n')
+			line--;
+	}
+	for (; buffer[i] && buffer[i] != '\n'; i++)
+		trace_seq_putc(&s, buffer[i]);
+	trace_seq_putc(&s, '\n');
+	for (i = idx; i > 0; i--)
+		trace_seq_putc(&s, ' ');
+	trace_seq_puts(&s, "^\n");
+	trace_seq_printf(&s, "ERROR: '%s'\n", text);
+	trace_seq_vprintf(&s, fmt, ap);
+
+	trace_seq_terminate(&s);
+
+	sb->parse_error_str = strdup(s.buffer);
+	trace_seq_destroy(&s);
+}
+
+static inline unsigned int quick_hash(const char *str)
+{
+	unsigned int val = 0;
+	int len = strlen(str);
+
+	for (; len >= 4; str += 4, len -= 4) {
+		val += str[0];
+		val += str[1] << 8;
+		val += str[2] << 16;
+		val += str[3] << 24;
+	}
+	for (; len > 0; str++, len--)
+		val += str[0] << (len * 8);
+
+        val *= 2654435761;
+
+        return val & ((1 << HASH_BITS) - 1);
+}
+
+
+static struct str_hash *find_string(struct sqlhist_bison *sb, const char *str)
+{
+	unsigned int key = quick_hash(str);
+	struct str_hash *hash = sb->str_hash[key];
+
+	for (; hash; hash = hash->next) {
+		if (!strcmp(hash->str, str))
+			return hash;
+	}
+	return NULL;
+}
+
+/*
+ * If @str is found, then return the hash string.
+ * This lets store_str() know to free str.
+ */
+static char **add_hash(struct sqlhist_bison *sb, const char *str)
+{
+	struct str_hash *hash;
+	unsigned int key;
+
+	if ((hash = find_string(sb, str))) {
+		return &hash->str;
+	}
+
+	hash = malloc(sizeof(*hash));
+	if (!hash)
+		return NULL;
+	key = quick_hash(str);
+	hash->next = sb->str_hash[key];
+	sb->str_hash[key] = hash;
+	hash->str = NULL;
+	return &hash->str;
+}
+
+__hidden char *store_str(struct sqlhist_bison *sb, const char *str)
+{
+	char **pstr = add_hash(sb, str);
+
+	if (!pstr)
+		return NULL;
+
+	if (!(*pstr))
+		*pstr = strdup(str);
+
+	return *pstr;
+}
+
+__hidden int add_selection(struct sqlhist_bison *sb, void *select,
+			   const char *name)
+{
+	struct sql_table *table = sb->table;
+	struct expr *expr = select;
+
+	switch (expr->type) {
+	case EXPR_FIELD:
+		break;
+	case EXPR_NUMBER:
+	case EXPR_STRING:
+	default:
+		return -1;
+	}
+
+	if (expr->next)
+		return -1;
+
+	*table->next_selection = expr;
+	table->next_selection = &expr->next;
+
+	return 0;
+}
+
+static struct expr *find_field(struct sqlhist_bison *sb,
+				const char *raw, const char *label)
+{
+	struct field *field;
+	struct expr *expr;
+
+	for_each_field(expr, field, sb->table) {
+		field = &expr->field;
+
+		if (!strcmp(field->raw, raw)) {
+			if (label && !field->label)
+				field->label = label;
+			return expr;
+		}
+
+		if (label && !strcmp(field->raw, label)) {
+			if (!field->label) {
+				field->label = label;
+				field->raw = raw;
+			}
+			return expr;
+		}
+
+		if (!field->label)
+			continue;
+
+		if (!strcmp(field->label, raw))
+			return expr;
+
+		if (label && !strcmp(field->label, label))
+			return expr;
+	}
+	return NULL;
+}
+
+static void *create_expr(enum expr_type type, struct expr **expr_p)
+{
+	struct expr *expr;
+
+	expr = calloc(1, sizeof(*expr));
+	if (!expr)
+		return NULL;
+
+	if (expr_p)
+		*expr_p = expr;
+
+	expr->free_list = sb->table->exprs;
+	sb->table->exprs = expr;
+
+	expr->type = type;
+
+	switch (type) {
+	case EXPR_FIELD:	return &expr->field;
+	case EXPR_NUMBER:	return &expr->number;
+	case EXPR_STRING:	return &expr->string;
+	}
+
+	return NULL;
+}
+
+#define __create_expr(var, type, ENUM, expr)			\
+	do {							\
+		var = (type *)create_expr(EXPR_##ENUM, expr);	\
+	} while(0)
+
+#define create_field(var, expr)				\
+	__create_expr(var, struct field, FIELD, expr)
+
+__hidden void *add_field(struct sqlhist_bison *sb,
+			 const char *field_name, const char *label)
+{
+	struct sql_table *table = sb->table;
+	struct expr *expr;
+	struct field *field;
+
+	expr = find_field(sb, field_name, label);
+	if (expr)
+		return expr;
+
+	create_field(field, &expr);
+
+	field->next = table->fields;
+	table->fields = expr;
+
+	field->raw = field_name;
+	field->label = label;
+
+	return expr;
+}
+
+__hidden int add_match(struct sqlhist_bison *sb, void *A, void *B)
+{
+	struct sql_table *table = sb->table;
+	struct match *match;
+
+	match = calloc(1, sizeof(*match));
+	if (!match)
+		return -1;
+
+	match->lval = A;
+	match->rval = B;
+
+	*table->next_match = match;
+	table->next_match = &match->next;
+
+	return 0;
+}
+
+__hidden int add_from(struct sqlhist_bison *sb, void *item)
+{
+	struct expr *expr = item;
+
+	if (expr->type != EXPR_FIELD)
+		return -1;
+
+	sb->table->from = expr;
+
+	return 0;
+}
+
+__hidden int add_to(struct sqlhist_bison *sb, void *item)
+{
+	struct expr *expr = item;
+
+	if (expr->type != EXPR_FIELD)
+		return -1;
+
+	sb->table->to = expr;
+
+	return 0;
+}
+
+__hidden int table_start(struct sqlhist_bison *sb)
+{
+	struct sql_table *table;
+
+	table = calloc(1, sizeof(*table));
+	if (!table)
+		return -ENOMEM;
+
+	table->sb = sb;
+	sb->table = table;
+
+	table->next_match = &table->matches;
+	table->next_selection = &table->selections;
+
+	return 0;
+}
+
+static int update_vars(struct sql_table *table, struct field *event)
+{
+	struct sqlhist_bison *sb = table->sb;
+	struct expr *expr;
+	struct field *field;
+	const char *label;
+	const char *p, *r;
+	char *system;
+	int len;
+
+	p = strchr(event->raw, '.');
+	if (p) {
+		system = strndup(event->raw, p - event->raw);
+		if (!system)
+			return -1;
+		event->system = store_str(sb, system);
+		free(system);
+		if (!event->system)
+			return -1;
+		p++;
+	} else {
+		p = event->raw;
+	}
+
+	event->event = store_str(sb, p);
+	if (!event->event)
+		return -1;
+
+	if (!event->label)
+		event->label = event->event;
+
+	label = event->label;
+	len = strlen(label);
+
+	for_each_field(expr, field, table) {
+		field = &expr->field;
+
+		if (field->event)
+			continue;
+
+		p = strchr(field->raw, '.');
+		if (p) {
+			/* Does this field have a system */
+			r = strchr(p + 1, '.');
+			if (r) {
+				/* This has a system, and is not a alias */
+				system = strndup(field->raw, p - field->raw);
+				if (!system)
+					return -1;
+				field->system = store_str(sb, system);
+				free(system);
+				if (!field->system)
+					return -1;
+
+				/* save the event as well */
+				p++;
+				system = strndup(p, r - p);
+				if (!system)
+					return -1;
+				field->event = store_str(sb, system);
+				free(system);
+				if (!field->event)
+					return -1;
+				r++;
+				field->field = store_str(sb, r);
+				goto check_timestamps;
+			}
+		}
+
+		if (strncmp(field->raw, label, len))
+			continue;
+
+		if (field->raw[len] != '.')
+			continue;
+
+		field->system = event->system;
+		field->event = event->event;
+		field->field = field->raw + len + 1;
+ check_timestamps:
+		if (!strcmp(field->field, "TIMESTAMP"))
+			field->field = store_str(sb, TRACEFS_TIMESTAMP);
+		else if (!strcmp(field->field, "TIMESTAMP_USECS"))
+			field->field = store_str(sb, TRACEFS_TIMESTAMP_USECS);
+	}
+
+	return 0;
+}
+
+static int test_match(struct sql_table *table, struct match *match)
+{
+	struct field *lval, *rval;
+	struct field *to, *from;
+
+	if (!match->lval || !match->rval)
+		return -1;
+
+	if (match->lval->type != EXPR_FIELD || match->rval->type != EXPR_FIELD)
+		return -1;
+
+	to = &table->to->field;
+	from = &table->from->field;
+
+	lval = &match->lval->field;
+	rval = &match->rval->field;
+
+	/*
+	 * Note, strings are stored in the string store, so all
+	 * duplicate strings are the same value, and we can use
+	 * normal "==" and "!=" instead of strcmp().
+	 *
+	 * Either lval == to and rval == from
+	 * or lval == from and rval == to.
+	 */
+	if ((lval->system != to->system) ||
+	    (lval->event != to->event)) {
+		if ((rval->system != to->system) ||
+		    (rval->event != to->event) ||
+		    (lval->system != from->system) ||
+		    (lval->event != from->event))
+			return -1;
+	} else {
+		if ((rval->system != from->system) ||
+		    (rval->event != from->event) ||
+		    (lval->system != to->system) ||
+		    (lval->event != to->event))
+			return -1;
+	}
+	return 0;
+}
+
+static void assign_match(const char *system, const char *event,
+			 struct match *match,
+			 const char **start_match, const char **end_match)
+{
+	struct field *lval, *rval;
+
+	lval = &match->lval->field;
+	rval = &match->rval->field;
+
+	if (lval->system == system &&
+	    lval->event == event) {
+		*start_match = lval->field;
+		*end_match = rval->field;
+	} else {
+		*start_match = rval->field;
+		*end_match = lval->field;
+	}
+}
+
+static struct tracefs_synth *build_synth(struct tep_handle *tep,
+					 const char *name,
+					 struct sql_table *table)
+{
+	struct tracefs_synth *synth;
+	struct field *field;
+	struct match *match;
+	struct expr *expr;
+	const char *start_system;
+	const char *start_event;
+	const char *end_system;
+	const char *end_event;
+	const char *start_match;
+	const char *end_match;
+	int ret;
+
+	if (!table->to || !table->from)
+		return NULL;
+
+	ret = update_vars(table, &table->to->field);
+	if (ret < 0)
+		return NULL;
+
+	ret = update_vars(table, &table->from->field);
+	if (ret < 0)
+		return NULL;
+
+	match = table->matches;
+	if (!match)
+		return NULL;
+
+	ret = test_match(table, match);
+	if (ret < 0)
+		return NULL;
+
+	start_system = table->from->field.system;
+	start_event = table->from->field.event;
+
+	end_system = table->to->field.system;
+	end_event = table->to->field.event;
+
+	assign_match(start_system, start_event, match,
+		     &start_match, &end_match);
+
+	synth = tracefs_synth_init(tep, name, start_system,
+				   start_event, end_system, end_event,
+				   start_match, end_match, NULL);
+	if (!synth)
+		return NULL;
+
+	for (match = match->next; match; match = match->next) {
+		ret = test_match(table, match);
+		if (ret < 0)
+			goto free;
+
+		assign_match(start_system, start_event, match,
+			     &start_match, &end_match);
+
+		ret = tracefs_synth_add_match_field(synth,
+						    start_match,
+						    end_match, NULL);
+		if (ret < 0)
+			goto free;
+	}
+
+	for (expr = table->selections; expr; expr = expr->next) {
+		if (expr->type == EXPR_FIELD) {
+			field = &expr->field;
+			if (field->system == start_system &&
+			    field->event == start_event) {
+				ret = tracefs_synth_add_start_field(synth,
+						field->field, field->label);
+			} else {
+				ret = tracefs_synth_add_end_field(synth,
+						field->field, field->label);
+			}
+			if (ret < 0)
+				goto free;
+			continue;
+		}
+		goto free;
+	}
+
+	return synth;
+ free:
+	tracefs_synth_free(synth);
+	return NULL;
+}
+
+static void free_sql_table(struct sql_table *table)
+{
+	struct match *match;
+	struct expr *expr;
+
+	if (!table)
+		return;
+
+	while ((expr = table->exprs)) {
+		table->exprs = expr->next;
+		free(expr);
+	}
+
+	while ((match = table->matches)) {
+		table->matches = match->next;
+		free(match);
+	}
+
+	free(table);
+}
+
+static void free_str_hash(struct str_hash **hash)
+{
+	struct str_hash *item;
+	int i;
+
+	for (i = 0; i < 1 << HASH_BITS; i++) {
+		while ((item = hash[i])) {
+			hash[i] = item->next;
+			free(item->str);
+			free(item);
+		}
+	}
+}
+
+static void free_sb(struct sqlhist_bison *sb)
+{
+	free_sql_table(sb->table);
+	free_str_hash(sb->str_hash);
+	free(sb->parse_error_str);
+}
+
+struct tracefs_synth *tracefs_sql(struct tep_handle *tep, const char *name,
+				  const char *sql_buffer, char **err)
+{
+	struct sqlhist_bison local_sb;
+	struct tracefs_synth *synth = NULL;
+	int ret;
+
+	if (!tep || !sql_buffer) {
+		errno = EINVAL;
+		return NULL;
+	}
+
+	memset(&local_sb, 0, sizeof(local_sb));
+
+	local_sb.buffer = sql_buffer;
+	local_sb.buffer_size = strlen(sql_buffer);
+	local_sb.buffer_idx = 0;
+
+	sb = &local_sb;
+	ret = yyparse();
+
+	if (ret)
+		goto free;
+
+	synth = build_synth(tep, name, sb->table);
+
+ free:
+	if (!synth) {
+		if (sb->parse_error_str && err) {
+			*err = sb->parse_error_str;
+			sb->parse_error_str = NULL;
+		}
+	}
+	free_sb(sb);
+	return synth;
+}
-- 
2.30.2


^ permalink raw reply	[flat|nested] 26+ messages in thread

* [PATCH 02/17] tracefs: Add unit tests for tracefs_sql()
  2021-07-30 22:18 [PATCH 00/17] libtracefs: Introducing tracefs_sql() to create synthetice events with an SQL line Steven Rostedt
  2021-07-30 22:18 ` [PATCH 01/17] libtracefs: Added new API tracefs_sql() Steven Rostedt
@ 2021-07-30 22:18 ` Steven Rostedt
  2021-07-30 22:18 ` [PATCH 03/17] libtracefs: Add comparing start and end fields in tracefs_sql() Steven Rostedt
                   ` (15 subsequent siblings)
  17 siblings, 0 replies; 26+ messages in thread
From: Steven Rostedt @ 2021-07-30 22:18 UTC (permalink / raw)
  To: linux-trace-devel
  Cc: linux-kernel, Tom Zanussi, Daniel Bristot de Oliveira,
	Masami Hiramatsu, Namhyung Kim, linux-rt-users, Clark Williams,
	Steven Rostedt (VMware)

From: "Steven Rostedt (VMware)" <rostedt@goodmis.org>

Add basic unit test for tracefs_sql()...

Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
---
 utest/tracefs-utest.c | 43 +++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 43 insertions(+)

diff --git a/utest/tracefs-utest.c b/utest/tracefs-utest.c
index 2a99217b938a..89bb1cce61f7 100644
--- a/utest/tracefs-utest.c
+++ b/utest/tracefs-utest.c
@@ -44,6 +44,12 @@
 #define KRETPROBE_ADDR	"do_sys_openat2"
 #define KRETPROBE_FMT	"ret=$retval"
 
+#define SQL_1_EVENT	"wakeup_1"
+#define SQL_1_SQL	"select sched_switch.next_pid as woke_pid, sched_waking.common_pid as waking_pid from sched_waking join sched_switch on sched_switch.next_pid = sched_waking.pid"
+
+#define SQL_2_EVENT	"wakeup_2"
+#define SQL_2_SQL	"select woke.next_pid as woke_pid, wake.common_pid as waking_pid from sched_waking as wake join sched_switch as woke on woke.next_pid = wake.pid"
+
 static struct tracefs_instance *test_instance;
 static struct tep_handle *test_tep;
 struct test_sample {
@@ -322,6 +328,41 @@ static void test_ftrace_marker(void)
 	test_instance_ftrace_marker(test_instance);
 }
 
+static void test_instance_trace_sql(struct tracefs_instance *instance)
+{
+	struct tracefs_synth *synth;
+	struct trace_seq seq;
+	struct tep_handle *tep;
+	int ret;
+
+	tep = tracefs_local_events(NULL);
+	CU_TEST(tep != NULL);
+
+	trace_seq_init(&seq);
+
+	synth = tracefs_sql(tep, SQL_1_EVENT, SQL_1_SQL, NULL);
+	CU_TEST(synth != NULL);
+	ret = tracefs_synth_show(&seq, instance, synth);
+	CU_TEST(ret == 0);
+	tracefs_synth_free(synth);
+	trace_seq_reset(&seq);
+
+	synth = tracefs_sql(tep, SQL_2_EVENT, SQL_2_SQL, NULL);
+	CU_TEST(synth != NULL);
+	ret = tracefs_synth_show(&seq, instance, synth);
+	CU_TEST(ret == 0);
+	tracefs_synth_free(synth);
+	trace_seq_reset(&seq);
+
+	tep_free(tep);
+	trace_seq_destroy(&seq);
+}
+
+static void test_trace_sql(void)
+{
+	test_instance_trace_sql(test_instance);
+}
+
 static void test_trace_file(void)
 {
 	const char *tmp = get_rand_str();
@@ -1338,6 +1379,8 @@ void test_tracefs_lib(void)
 		fprintf(stderr, "Suite \"%s\" cannot be ceated\n", TRACEFS_SUITE);
 		return;
 	}
+	CU_add_test(suite, "trace sql",
+		    test_trace_sql);
 	CU_add_test(suite, "tracing file / directory APIs",
 		    test_trace_file);
 	CU_add_test(suite, "instance file / directory APIs",
-- 
2.30.2


^ permalink raw reply	[flat|nested] 26+ messages in thread

* [PATCH 03/17] libtracefs: Add comparing start and end fields in tracefs_sql()
  2021-07-30 22:18 [PATCH 00/17] libtracefs: Introducing tracefs_sql() to create synthetice events with an SQL line Steven Rostedt
  2021-07-30 22:18 ` [PATCH 01/17] libtracefs: Added new API tracefs_sql() Steven Rostedt
  2021-07-30 22:18 ` [PATCH 02/17] tracefs: Add unit tests for tracefs_sql() Steven Rostedt
@ 2021-07-30 22:18 ` Steven Rostedt
  2021-07-30 22:18 ` [PATCH 04/17] libtracefs: Add unit test to test tracefs_sql() compare Steven Rostedt
                   ` (14 subsequent siblings)
  17 siblings, 0 replies; 26+ messages in thread
From: Steven Rostedt @ 2021-07-30 22:18 UTC (permalink / raw)
  To: linux-trace-devel
  Cc: linux-kernel, Tom Zanussi, Daniel Bristot de Oliveira,
	Masami Hiramatsu, Namhyung Kim, linux-rt-users, Clark Williams,
	Steven Rostedt (VMware)

From: "Steven Rostedt (VMware)" <rostedt@goodmis.org>

Add comparing a field and showing the differences between start and end
for tracefs_sql().

For example:

  SELECT (end.common_timestamp.usecs - start.common_timestamp.usecs) AS
    lat FROM sched_waking AS start JOIN sched_switch AS end ON
    start.pid = stop.next_pid

Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
---
 src/sqlhist-parse.h   |  4 ++
 src/sqlhist.y         | 19 ++++++++++
 src/tracefs-sqlhist.c | 85 ++++++++++++++++++++++++++++++++++++++++++-
 3 files changed, 107 insertions(+), 1 deletion(-)

diff --git a/src/sqlhist-parse.h b/src/sqlhist-parse.h
index aa5232eea451..ebf4f61b5461 100644
--- a/src/sqlhist-parse.h
+++ b/src/sqlhist-parse.h
@@ -57,7 +57,11 @@ int table_start(struct sqlhist_bison *sb);
 
 void *add_field(struct sqlhist_bison *sb, const char *field, const char *label);
 
+void *add_filter(struct sqlhist_bison *sb, void *A, void *B, enum filter_type op);
+
 int add_match(struct sqlhist_bison *sb, void *A, void *B);
+void *add_compare(struct sqlhist_bison *sb, void *A, void *B, enum compare_type type);
+int add_where(struct sqlhist_bison *sb, void *expr);
 
 int add_selection(struct sqlhist_bison *sb, void *item, const char *label);
 int add_from(struct sqlhist_bison *sb, void *item);
diff --git a/src/sqlhist.y b/src/sqlhist.y
index ecb0a0ed44b3..f92c93ed5ecd 100644
--- a/src/sqlhist.y
+++ b/src/sqlhist.y
@@ -48,6 +48,10 @@ extern void yyerror(char *fmt, ...);
 %type <string> name label
 
 %type <expr>  selection_expr field item named_field join_clause
+%type <expr>  selection_addition
+%type <expr>  compare compare_list compare_cmds compare_items
+%type <expr>  compare_and_or
+%type <expr>  str_val val
 
 %%
 
@@ -85,6 +89,21 @@ selection :
 selection_expr :
    field
  | '(' field ')'		{  $$ = $2; }
+ | selection_addition
+ | '(' selection_addition ')'	{  $$ = $2; }
+ ;
+
+selection_addition :
+   field '+' field
+				{
+					$$ = add_compare(sb, $1, $3, COMPARE_ADD);
+					CHECK_RETURN_PTR($$);
+				}
+ | field '-' field
+				{
+					$$ = add_compare(sb, $1, $3, COMPARE_SUB);
+					CHECK_RETURN_PTR($$);
+				}
  ;
 
 item :
diff --git a/src/tracefs-sqlhist.c b/src/tracefs-sqlhist.c
index 7ec0c11b902e..cf2661773679 100644
--- a/src/tracefs-sqlhist.c
+++ b/src/tracefs-sqlhist.c
@@ -42,17 +42,32 @@ struct field {
 	const char		*field;
 };
 
+struct filter {
+	enum filter_type	type;
+	struct expr		*lval;
+	struct expr		*rval;
+};
+
 struct match {
 	struct match		*next;
 	struct expr		*lval;
 	struct expr		*rval;
 };
 
+struct compare {
+	enum compare_type	type;
+	struct expr		*lval;
+	struct expr		*rval;
+	const char		*name;
+};
+
 enum expr_type
 {
 	EXPR_NUMBER,
 	EXPR_STRING,
 	EXPR_FIELD,
+	EXPR_FILTER,
+	EXPR_COMPARE,
 };
 
 struct expr {
@@ -61,6 +76,8 @@ struct expr {
 	enum expr_type		type;
 	union {
 		struct field	field;
+		struct filter	filter;
+		struct compare	compare;
 		const char	*string;
 		long		number;
 	};
@@ -209,8 +226,14 @@ __hidden int add_selection(struct sqlhist_bison *sb, void *select,
 	switch (expr->type) {
 	case EXPR_FIELD:
 		break;
+	case EXPR_COMPARE:
+		if (!name)
+			return -1;
+		expr->compare.name = name;
+		break;
 	case EXPR_NUMBER:
 	case EXPR_STRING:
+	case EXPR_FILTER:
 	default:
 		return -1;
 	}
@@ -277,8 +300,10 @@ static void *create_expr(enum expr_type type, struct expr **expr_p)
 
 	switch (type) {
 	case EXPR_FIELD:	return &expr->field;
+	case EXPR_COMPARE:	return &expr->compare;
 	case EXPR_NUMBER:	return &expr->number;
 	case EXPR_STRING:	return &expr->string;
+	case EXPR_FILTER:	return &expr->filter;
 	}
 
 	return NULL;
@@ -292,6 +317,9 @@ static void *create_expr(enum expr_type type, struct expr **expr_p)
 #define create_field(var, expr)				\
 	__create_expr(var, struct field, FIELD, expr)
 
+#define create_compare(var, expr)				\
+	__create_expr(var, struct compare, COMPARE, expr)
+
 __hidden void *add_field(struct sqlhist_bison *sb,
 			 const char *field_name, const char *label)
 {
@@ -331,6 +359,21 @@ __hidden int add_match(struct sqlhist_bison *sb, void *A, void *B)
 
 	return 0;
 }
+__hidden void *add_compare(struct sqlhist_bison *sb,
+			   void *A, void *B, enum compare_type type)
+{
+	struct compare *compare;
+	struct expr *expr;
+
+	create_compare(compare, &expr);
+
+	compare = &expr->compare;
+	compare->lval = A;
+	compare->rval = B;
+	compare->type = type;
+
+	return expr;
+}
 
 __hidden int add_from(struct sqlhist_bison *sb, void *item)
 {
@@ -522,6 +565,39 @@ static void assign_match(const char *system, const char *event,
 	}
 }
 
+static int build_compare(struct tracefs_synth *synth,
+			 const char *system, const char *event,
+			 struct compare *compare)
+{
+	const char *start_field;
+	const char *end_field;
+	struct field *lval, *rval;
+	enum tracefs_synth_calc calc;
+	int ret;
+
+	lval = &compare->lval->field;
+	rval = &compare->rval->field;
+
+	if (lval->system == system &&
+	    lval->event == event) {
+		start_field = lval->field;
+		end_field = rval->field;
+		calc = TRACEFS_SYNTH_DELTA_START;
+	} else {
+		start_field = rval->field;
+		end_field = lval->field;
+		calc = TRACEFS_SYNTH_DELTA_END;
+	}
+
+	if (compare->type == COMPARE_ADD)
+		calc = TRACEFS_SYNTH_ADD;
+
+	ret = tracefs_synth_add_compare_field(synth, start_field,
+					      end_field, calc,
+					      compare->name);
+	return ret;
+}
+
 static struct tracefs_synth *build_synth(struct tep_handle *tep,
 					 const char *name,
 					 struct sql_table *table)
@@ -602,7 +678,14 @@ static struct tracefs_synth *build_synth(struct tep_handle *tep,
 				goto free;
 			continue;
 		}
-		goto free;
+
+		if (expr->type != EXPR_COMPARE)
+			goto free;
+
+		ret = build_compare(synth, start_system, end_system,
+				    &expr->compare);
+		if (ret < 0)
+			goto free;
 	}
 
 	return synth;
-- 
2.30.2


^ permalink raw reply	[flat|nested] 26+ messages in thread

* [PATCH 04/17] libtracefs: Add unit test to test tracefs_sql() compare
  2021-07-30 22:18 [PATCH 00/17] libtracefs: Introducing tracefs_sql() to create synthetice events with an SQL line Steven Rostedt
                   ` (2 preceding siblings ...)
  2021-07-30 22:18 ` [PATCH 03/17] libtracefs: Add comparing start and end fields in tracefs_sql() Steven Rostedt
@ 2021-07-30 22:18 ` Steven Rostedt
  2021-07-30 22:18 ` [PATCH 05/17] libtracefs: Add filtering for start and end events in tracefs_sql() Steven Rostedt
                   ` (13 subsequent siblings)
  17 siblings, 0 replies; 26+ messages in thread
From: Steven Rostedt @ 2021-07-30 22:18 UTC (permalink / raw)
  To: linux-trace-devel
  Cc: linux-kernel, Tom Zanussi, Daniel Bristot de Oliveira,
	Masami Hiramatsu, Namhyung Kim, linux-rt-users, Clark Williams,
	Steven Rostedt (VMware)

From: "Steven Rostedt (VMware)" <rostedt@goodmis.org>

Add a test to test passing time from sched_waking to sched_switch to
show wake up latency.

Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
---
 utest/tracefs-utest.c | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/utest/tracefs-utest.c b/utest/tracefs-utest.c
index 89bb1cce61f7..f4e1a6b90a46 100644
--- a/utest/tracefs-utest.c
+++ b/utest/tracefs-utest.c
@@ -50,6 +50,9 @@
 #define SQL_2_EVENT	"wakeup_2"
 #define SQL_2_SQL	"select woke.next_pid as woke_pid, wake.common_pid as waking_pid from sched_waking as wake join sched_switch as woke on woke.next_pid = wake.pid"
 
+#define SQL_3_EVENT	"wakeup_lat"
+#define SQL_3_SQL	"select start.pid, end.next_prio as prio, (end.TIMESTAMP_USECS - start.TIMESTAMP_USECS) as lat from sched_waking as start join sched_switch as end on start.pid = end.next_pid"
+
 static struct tracefs_instance *test_instance;
 static struct tep_handle *test_tep;
 struct test_sample {
@@ -354,6 +357,13 @@ static void test_instance_trace_sql(struct tracefs_instance *instance)
 	tracefs_synth_free(synth);
 	trace_seq_reset(&seq);
 
+	synth = tracefs_sql(tep, SQL_3_EVENT, SQL_3_SQL, NULL);
+	CU_TEST(synth != NULL);
+	ret = tracefs_synth_show(&seq, instance, synth);
+	CU_TEST(ret == 0);
+	tracefs_synth_free(synth);
+	trace_seq_reset(&seq);
+
 	tep_free(tep);
 	trace_seq_destroy(&seq);
 }
-- 
2.30.2


^ permalink raw reply	[flat|nested] 26+ messages in thread

* [PATCH 05/17] libtracefs: Add filtering for start and end events in tracefs_sql()
  2021-07-30 22:18 [PATCH 00/17] libtracefs: Introducing tracefs_sql() to create synthetice events with an SQL line Steven Rostedt
                   ` (3 preceding siblings ...)
  2021-07-30 22:18 ` [PATCH 04/17] libtracefs: Add unit test to test tracefs_sql() compare Steven Rostedt
@ 2021-07-30 22:18 ` Steven Rostedt
  2021-07-30 22:18 ` [PATCH 06/17] libtracefs: Add unit test to test tracefs_sql() where clause Steven Rostedt
                   ` (12 subsequent siblings)
  17 siblings, 0 replies; 26+ messages in thread
From: Steven Rostedt @ 2021-07-30 22:18 UTC (permalink / raw)
  To: linux-trace-devel
  Cc: linux-kernel, Tom Zanussi, Daniel Bristot de Oliveira,
	Masami Hiramatsu, Namhyung Kim, linux-rt-users, Clark Williams,
	Steven Rostedt (VMware)

From: "Steven Rostedt (VMware)" <rostedt@goodmis.org>

Allow the start and end events to have filters with the "WHERE" clause.

For example:

  SELECT (end.common_timestamp.usecs - start.common_timestamp.usecs) AS
    lat FROM sched_waking AS start JOIN sched_switch AS end ON
    start.pid = stop.next_pid WHERE start.prio < 100 &&
    end.prev_prio < 100

Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
---
 src/sqlhist-parse.h   |   3 +
 src/sqlhist.l         |   1 +
 src/sqlhist.y         |  67 ++++++++++-
 src/tracefs-sqlhist.c | 260 ++++++++++++++++++++++++++++++++++++++++++
 4 files changed, 329 insertions(+), 2 deletions(-)

diff --git a/src/sqlhist-parse.h b/src/sqlhist-parse.h
index ebf4f61b5461..0933bfe9a574 100644
--- a/src/sqlhist-parse.h
+++ b/src/sqlhist-parse.h
@@ -67,6 +67,9 @@ int add_selection(struct sqlhist_bison *sb, void *item, const char *label);
 int add_from(struct sqlhist_bison *sb, void *item);
 int add_to(struct sqlhist_bison *sb, void *item);
 
+void *add_string(struct sqlhist_bison *sb, const char *str);
+void *add_number(struct sqlhist_bison *sb, long val);
+
 extern void sql_parse_error(struct sqlhist_bison *sb, const char *text,
 			    const char *fmt, va_list ap);
 
diff --git a/src/sqlhist.l b/src/sqlhist.l
index 3f394f37b738..476f7fd1f1ec 100644
--- a/src/sqlhist.l
+++ b/src/sqlhist.l
@@ -32,6 +32,7 @@ as { HANDLE_COLUMN; return AS; }
 from { HANDLE_COLUMN; return FROM; }
 join { HANDLE_COLUMN; return JOIN; }
 on { HANDLE_COLUMN; return ON; }
+where { HANDLE_COLUMN; return WHERE; }
 
 {qstring} {
 	HANDLE_COLUMN;
diff --git a/src/sqlhist.y b/src/sqlhist.y
index f92c93ed5ecd..8dcc824bb9f1 100644
--- a/src/sqlhist.y
+++ b/src/sqlhist.y
@@ -34,7 +34,7 @@ extern void yyerror(char *fmt, ...);
 	void	*expr;
 }
 
-%token AS SELECT FROM JOIN ON PARSE_ERROR
+%token AS SELECT FROM JOIN ON WHERE PARSE_ERROR
 %token <number> NUMBER
 %token <string> STRING
 %token <string> FIELD
@@ -123,8 +123,71 @@ name :
    FIELD
  ;
 
+str_val :
+   STRING	{ $$ = add_string(sb, $1); CHECK_RETURN_PTR($$); }
+ ;
+
+val :
+   str_val
+ | NUMBER	{ $$ = add_number(sb, $1); CHECK_RETURN_PTR($$); }
+ ;
+
+
+compare :
+   field '<' val	{ $$ = add_filter(sb, $1, $3, FILTER_LT); CHECK_RETURN_PTR($$); }
+ | field '>' val	{ $$ = add_filter(sb, $1, $3, FILTER_GT); CHECK_RETURN_PTR($$); }
+ | field LE val	{ $$ = add_filter(sb, $1, $3, FILTER_LE); CHECK_RETURN_PTR($$); }
+ | field GE val	{ $$ = add_filter(sb, $1, $3, FILTER_GE); CHECK_RETURN_PTR($$); }
+ | field '=' val	{ $$ = add_filter(sb, $1, $3, FILTER_EQ); CHECK_RETURN_PTR($$); }
+ | field EQ val	{ $$ = add_filter(sb, $1, $3, FILTER_EQ); CHECK_RETURN_PTR($$); }
+ | field NEQ val	{ $$ = add_filter(sb, $1, $3, FILTER_NE); CHECK_RETURN_PTR($$); }
+ | field "!=" val	{ $$ = add_filter(sb, $1, $3, FILTER_NE); CHECK_RETURN_PTR($$); }
+ | field '&' val	{ $$ = add_filter(sb, $1, $3, FILTER_BIN_AND); CHECK_RETURN_PTR($$); }
+ | field '~' str_val	{ $$ = add_filter(sb, $1, $3, FILTER_STR_CMP); CHECK_RETURN_PTR($$); }
+;
+
+compare_and_or :
+   compare_and_or OR compare_and_or	{ $$ = add_filter(sb, $1, $3, FILTER_OR); CHECK_RETURN_PTR($$); }
+ | compare_and_or AND compare_and_or	{ $$ = add_filter(sb, $1, $3, FILTER_AND); CHECK_RETURN_PTR($$); }
+ | '!' '(' compare_and_or ')'		{ $$ = add_filter(sb, $3, NULL, FILTER_NOT_GROUP); CHECK_RETURN_PTR($$); }
+ | '!' compare				{ $$ = add_filter(sb, $2, NULL, FILTER_NOT_GROUP); CHECK_RETURN_PTR($$); }
+ | compare
+ ;
+
+compare_items :
+   compare_items OR compare_items	{ $$ = add_filter(sb, $1, $3, FILTER_OR); CHECK_RETURN_PTR($$); }
+ | '(' compare_and_or ')'		{ $$ = add_filter(sb, $2, NULL, FILTER_GROUP); CHECK_RETURN_PTR($$); }
+ | '!' '(' compare_and_or ')'		{ $$ = add_filter(sb, $3, NULL, FILTER_NOT_GROUP); CHECK_RETURN_PTR($$); }
+ | '!' compare				{ $$ = add_filter(sb, $2, NULL, FILTER_NOT_GROUP); CHECK_RETURN_PTR($$); }
+ | compare
+ ;
+
+compare_cmds :
+   compare_items		{ CHECK_RETURN_VAL(add_where(sb, $1)); }
+ ;
+
+/*
+ * Top level AND is equal to ',' but the compare_cmds in them must
+ * all be of for the same event (start or end exclusive).
+ * That is, OR is not to be used between start and end events.
+ */
+compare_list :
+   compare_cmds
+ | compare_cmds ',' compare_list
+ | compare_cmds AND compare_list
+ ;
+
+where_clause :
+   WHERE compare_list
+ ;
+
+opt_where_clause :
+   /* empty */
+ | where_clause
+;
+
 table_exp :
-   from_clause join_clause
+   from_clause join_clause opt_where_clause
  ;
 
 from_clause :
diff --git a/src/tracefs-sqlhist.c b/src/tracefs-sqlhist.c
index cf2661773679..e47bc57c5add 100644
--- a/src/tracefs-sqlhist.c
+++ b/src/tracefs-sqlhist.c
@@ -90,6 +90,8 @@ struct sql_table {
 	struct expr		*fields;
 	struct expr		*from;
 	struct expr		*to;
+	struct expr		*where;
+	struct expr		**next_where;
 	struct match		*matches;
 	struct match		**next_match;
 	struct expr		*selections;
@@ -317,9 +319,18 @@ static void *create_expr(enum expr_type type, struct expr **expr_p)
 #define create_field(var, expr)				\
 	__create_expr(var, struct field, FIELD, expr)
 
+#define create_filter(var, expr)			\
+	__create_expr(var, struct filter, FILTER, expr)
+
 #define create_compare(var, expr)				\
 	__create_expr(var, struct compare, COMPARE, expr)
 
+#define create_string(var, expr)			\
+	__create_expr(var, const char *, STRING, expr)
+
+#define create_number(var, expr)			\
+	__create_expr(var, long, NUMBER, expr)
+
 __hidden void *add_field(struct sqlhist_bison *sb,
 			 const char *field_name, const char *label)
 {
@@ -342,6 +353,22 @@ __hidden void *add_field(struct sqlhist_bison *sb,
 	return expr;
 }
 
+__hidden void *add_filter(struct sqlhist_bison *sb,
+			  void *A, void *B, enum filter_type op)
+{
+	struct filter *filter;
+	struct expr *expr;
+
+	create_filter(filter, &expr);
+
+	filter->lval = A;
+	filter->rval = B;
+
+	filter->type = op;
+
+	return expr;
+}
+
 __hidden int add_match(struct sqlhist_bison *sb, void *A, void *B)
 {
 	struct sql_table *table = sb->table;
@@ -375,6 +402,23 @@ __hidden void *add_compare(struct sqlhist_bison *sb,
 	return expr;
 }
 
+__hidden int add_where(struct sqlhist_bison *sb, void *item)
+{
+	struct expr *expr = item;
+	struct sql_table *table = sb->table;
+
+	if (expr->type != EXPR_FILTER)
+		return -1;
+
+	*table->next_where = expr;
+	table->next_where = &expr->next;
+
+	if (expr->next)
+		return -1;
+
+	return 0;
+}
+
 __hidden int add_from(struct sqlhist_bison *sb, void *item)
 {
 	struct expr *expr = item;
@@ -399,6 +443,34 @@ __hidden int add_to(struct sqlhist_bison *sb, void *item)
 	return 0;
 }
 
+__hidden void *add_string(struct sqlhist_bison *sb, const char *str)
+{
+	struct expr *expr;
+	const char **str_p;
+
+	create_string(str_p, &expr);
+	*str_p = str;
+	return expr;
+}
+
+__hidden void *add_number(struct sqlhist_bison *sb, long val)
+{
+	struct expr *expr;
+	long *num;
+
+	create_number(num, &expr);
+	*num = val;
+	return expr;
+
+	expr = calloc(1, sizeof(expr));
+	if (!expr)
+		return NULL;
+
+	expr->type = EXPR_NUMBER;
+	expr->number = val;
+	return expr;
+}
+
 __hidden int table_start(struct sqlhist_bison *sb)
 {
 	struct sql_table *table;
@@ -410,6 +482,7 @@ __hidden int table_start(struct sqlhist_bison *sb)
 	table->sb = sb;
 	sb->table = table;
 
+	table->next_where = &table->where;
 	table->next_match = &table->matches;
 	table->next_selection = &table->selections;
 
@@ -598,6 +671,167 @@ static int build_compare(struct tracefs_synth *synth,
 	return ret;
 }
 
+static int do_verify_filter(struct filter *filter,
+			    const char **system, const char **event)
+{
+	int ret;
+
+	if (filter->type == FILTER_OR ||
+	    filter->type == FILTER_AND) {
+		ret = do_verify_filter(&filter->lval->filter, system, event);
+		if (ret)
+			return ret;
+		return do_verify_filter(&filter->rval->filter, system, event);
+	}
+	if (filter->type == FILTER_GROUP ||
+	    filter->type == FILTER_NOT_GROUP) {
+		return do_verify_filter(&filter->lval->filter, system, event);
+	}
+
+	/*
+	 * system and event will be NULL until we find the left most
+	 * node. Then assign it, and compare on the way back up.
+	 */
+	if (!*system && !*event) {
+		*system = filter->lval->field.system;
+		*event = filter->lval->field.event;
+		return 0;
+	}
+
+	if (filter->lval->field.system != *system ||
+	    filter->lval->field.event != *event)
+		return -1;
+
+	return 0;
+}
+
+static int verify_filter(struct filter *filter,
+			 const char **system, const char **event)
+{
+	int ret;
+
+	switch (filter->type) {
+	case FILTER_OR:
+	case FILTER_AND:
+	case FILTER_GROUP:
+	case FILTER_NOT_GROUP:
+		break;
+	default:
+		return do_verify_filter(filter, system, event);
+	}
+
+	ret = do_verify_filter(&filter->lval->filter, system, event);
+	if (ret)
+		return ret;
+
+	switch (filter->type) {
+	case FILTER_OR:
+	case FILTER_AND:
+		return do_verify_filter(&filter->rval->filter, system, event);
+	default:
+		return 0;
+	}
+}
+
+static int build_filter(struct tracefs_synth *synth,
+			bool start, struct filter *filter, bool *started)
+{
+	int (*append_filter)(struct tracefs_synth *synth,
+			     enum tracefs_filter type,
+			     const char *field,
+			     enum tracefs_compare compare,
+			     const char *val);
+	enum tracefs_compare cmp;
+	const char *val;
+	int and_or = TRACEFS_FILTER_AND;
+	char num[64];
+	int ret;
+
+	if (start)
+		append_filter = tracefs_synth_append_start_filter;
+	else
+		append_filter = tracefs_synth_append_end_filter;
+
+	if (started && *started) {
+		ret = append_filter(synth, and_or, NULL, 0, NULL);
+		ret = append_filter(synth, TRACEFS_FILTER_OPEN_PAREN,
+				    NULL, 0, NULL);
+	}
+
+	switch (filter->type) {
+	case FILTER_NOT_GROUP:
+		ret = append_filter(synth, TRACEFS_FILTER_NOT,
+				    NULL, 0, NULL);
+		if (ret < 0)
+			goto out;
+		/* Fall through */
+	case FILTER_GROUP:
+		ret = append_filter(synth, TRACEFS_FILTER_OPEN_PAREN,
+				    NULL, 0, NULL);
+		if (ret < 0)
+			goto out;
+		ret = build_filter(synth, start, &filter->lval->filter, NULL);
+		if (ret < 0)
+			goto out;
+		ret = append_filter(synth, TRACEFS_FILTER_CLOSE_PAREN,
+				    NULL, 0, NULL);
+		goto out;
+
+	case FILTER_OR:
+		and_or = TRACEFS_FILTER_OR;
+		/* Fall through */
+	case FILTER_AND:
+		ret = build_filter(synth, start, &filter->lval->filter, NULL);
+		if (ret < 0)
+			goto out;
+		ret = append_filter(synth, and_or, NULL, 0, NULL);
+
+		if (ret)
+			goto out;
+		ret = build_filter(synth, start, &filter->rval->filter, NULL);
+		goto out;
+	default:
+		break;
+	}
+
+	switch (filter->rval->type) {
+	case EXPR_NUMBER:
+		sprintf(num, "%ld", filter->rval->number);
+		val = num;
+		break;
+	case EXPR_STRING:
+		val = filter->rval->string;
+		break;
+	default:
+		break;
+	}
+
+	switch (filter->type) {
+	case FILTER_EQ:		cmp = TRACEFS_COMPARE_EQ; break;
+	case FILTER_NE:		cmp = TRACEFS_COMPARE_NE; break;
+	case FILTER_LE:		cmp = TRACEFS_COMPARE_LE; break;
+	case FILTER_LT:		cmp = TRACEFS_COMPARE_LT; break;
+	case FILTER_GE:		cmp = TRACEFS_COMPARE_GE; break;
+	case FILTER_GT:		cmp = TRACEFS_COMPARE_GT; break;
+	case FILTER_BIN_AND:	cmp = TRACEFS_COMPARE_AND; break;
+	case FILTER_STR_CMP:	cmp = TRACEFS_COMPARE_RE; break;
+	default:
+		break;
+	}
+
+	ret = append_filter(synth, TRACEFS_FILTER_COMPARE,
+			    filter->lval->field.field, cmp, val);
+
+ out:
+	if (!ret && started) {
+		if (*started)
+			ret = append_filter(synth, TRACEFS_FILTER_CLOSE_PAREN,
+					    NULL, 0, NULL);
+		*started = true;
+	}
+	return ret;
+}
+
 static struct tracefs_synth *build_synth(struct tep_handle *tep,
 					 const char *name,
 					 struct sql_table *table)
@@ -612,6 +846,8 @@ static struct tracefs_synth *build_synth(struct tep_handle *tep,
 	const char *end_event;
 	const char *start_match;
 	const char *end_match;
+	bool started_start = false;
+	bool started_end = false;
 	int ret;
 
 	if (!table->to || !table->from)
@@ -688,6 +924,30 @@ static struct tracefs_synth *build_synth(struct tep_handle *tep,
 			goto free;
 	}
 
+	for (expr = table->where; expr; expr = expr->next) {
+		const char *filter_system = NULL;
+		const char *filter_event = NULL;
+		bool *started;
+		bool start;
+
+		ret = verify_filter(&expr->filter, &filter_system,
+				    &filter_event);
+		if (ret < 0)
+			goto free;
+
+		start = filter_system == start_system &&
+			filter_event == start_event;
+
+		if (start)
+			started = &started_start;
+		else
+			started = &started_end;
+
+		ret = build_filter(synth, start, &expr->filter, started);
+		if (ret < 0)
+			goto free;
+	}
+
 	return synth;
  free:
 	tracefs_synth_free(synth);
-- 
2.30.2


^ permalink raw reply	[flat|nested] 26+ messages in thread

* [PATCH 06/17] libtracefs: Add unit test to test tracefs_sql() where clause
  2021-07-30 22:18 [PATCH 00/17] libtracefs: Introducing tracefs_sql() to create synthetice events with an SQL line Steven Rostedt
                   ` (4 preceding siblings ...)
  2021-07-30 22:18 ` [PATCH 05/17] libtracefs: Add filtering for start and end events in tracefs_sql() Steven Rostedt
@ 2021-07-30 22:18 ` Steven Rostedt
  2021-07-30 22:18 ` [PATCH 07/17] libtracefs: Make sqlhist parser reentrant Steven Rostedt
                   ` (11 subsequent siblings)
  17 siblings, 0 replies; 26+ messages in thread
From: Steven Rostedt @ 2021-07-30 22:18 UTC (permalink / raw)
  To: linux-trace-devel
  Cc: linux-kernel, Tom Zanussi, Daniel Bristot de Oliveira,
	Masami Hiramatsu, Namhyung Kim, linux-rt-users, Clark Williams,
	Steven Rostedt (VMware)

From: "Steven Rostedt (VMware)" <rostedt@goodmis.org>

Add a test to test filtering of events via the WHERE clause.

Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
---
 utest/tracefs-utest.c | 25 +++++++++++++++++++++++++
 1 file changed, 25 insertions(+)

diff --git a/utest/tracefs-utest.c b/utest/tracefs-utest.c
index f4e1a6b90a46..645c84c31f0e 100644
--- a/utest/tracefs-utest.c
+++ b/utest/tracefs-utest.c
@@ -53,6 +53,13 @@
 #define SQL_3_EVENT	"wakeup_lat"
 #define SQL_3_SQL	"select start.pid, end.next_prio as prio, (end.TIMESTAMP_USECS - start.TIMESTAMP_USECS) as lat from sched_waking as start join sched_switch as end on start.pid = end.next_pid"
 
+#define SQL_4_EVENT	"wakeup_lat_2"
+#define SQL_4_SQL	"select start.pid, end.next_prio as prio, (end.TIMESTAMP_USECS - start.TIMESTAMP_USECS) as lat from sched_waking as start join sched_switch as end on start.pid = end.next_pid where (start.prio >= 1 && start.prio < 100) || !(start.pid >= 0 && start.pid <= 1) && end.prev_pid != 0"
+
+#define SQL_5_EVENT	"irq_lat"
+#define SQL_5_SQL	"select end.common_pid as pid, (end.common_timestamp.usecs - start.common_timestamp.usecs) as irq_lat from irq_disable as start join irq_enable as end on start.common_pid = end.common_pid, start.parent_offs == end.parent_offs where start.common_pid != 0"
+#define SQL_5_START	"irq_disable"
+
 static struct tracefs_instance *test_instance;
 static struct tep_handle *test_tep;
 struct test_sample {
@@ -336,6 +343,7 @@ static void test_instance_trace_sql(struct tracefs_instance *instance)
 	struct tracefs_synth *synth;
 	struct trace_seq seq;
 	struct tep_handle *tep;
+	struct tep_event *event;
 	int ret;
 
 	tep = tracefs_local_events(NULL);
@@ -364,6 +372,23 @@ static void test_instance_trace_sql(struct tracefs_instance *instance)
 	tracefs_synth_free(synth);
 	trace_seq_reset(&seq);
 
+	synth = tracefs_sql(tep, SQL_4_EVENT, SQL_4_SQL, NULL);
+	CU_TEST(synth != NULL);
+	ret = tracefs_synth_show(&seq, instance, synth);
+	CU_TEST(ret == 0);
+	tracefs_synth_free(synth);
+	trace_seq_reset(&seq);
+
+	event = tep_find_event_by_name(tep, NULL, SQL_5_START);
+	if (event) {
+		synth = tracefs_sql(tep, SQL_5_EVENT, SQL_5_SQL, NULL);
+		CU_TEST(synth != NULL);
+		ret = tracefs_synth_show(&seq, instance, synth);
+		CU_TEST(ret == 0);
+		tracefs_synth_free(synth);
+		trace_seq_reset(&seq);
+	}
+
 	tep_free(tep);
 	trace_seq_destroy(&seq);
 }
-- 
2.30.2


^ permalink raw reply	[flat|nested] 26+ messages in thread

* [PATCH 07/17] libtracefs: Make sqlhist parser reentrant
  2021-07-30 22:18 [PATCH 00/17] libtracefs: Introducing tracefs_sql() to create synthetice events with an SQL line Steven Rostedt
                   ` (5 preceding siblings ...)
  2021-07-30 22:18 ` [PATCH 06/17] libtracefs: Add unit test to test tracefs_sql() where clause Steven Rostedt
@ 2021-07-30 22:18 ` Steven Rostedt
  2021-07-30 22:18 ` [PATCH 08/17] libtracefs: Make parser unique to libtracefs Steven Rostedt
                   ` (10 subsequent siblings)
  17 siblings, 0 replies; 26+ messages in thread
From: Steven Rostedt @ 2021-07-30 22:18 UTC (permalink / raw)
  To: linux-trace-devel
  Cc: linux-kernel, Tom Zanussi, Daniel Bristot de Oliveira,
	Masami Hiramatsu, Namhyung Kim, linux-rt-users, Clark Williams,
	Steven Rostedt (VMware)

From: "Steven Rostedt (VMware)" <rostedt@goodmis.org>

Update bison and flex to be reentrant, and not depend on any global
variables.

Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
---
 src/sqlhist-parse.h   |  3 +--
 src/sqlhist.l         | 26 ++++++++++++++++----------
 src/sqlhist.y         | 10 ++++++++--
 src/tracefs-sqlhist.c | 41 ++++++++++++++++++++++++-----------------
 4 files changed, 49 insertions(+), 31 deletions(-)

diff --git a/src/sqlhist-parse.h b/src/sqlhist-parse.h
index 0933bfe9a574..7c1b97ca65af 100644
--- a/src/sqlhist-parse.h
+++ b/src/sqlhist-parse.h
@@ -10,6 +10,7 @@ struct str_hash;
 struct sql_table;
 
 struct sqlhist_bison {
+	void			*scanner;
 	const char		*buffer;
 	size_t			buffer_size;
 	size_t			buffer_idx;
@@ -20,8 +21,6 @@ struct sqlhist_bison {
 	struct str_hash         *str_hash[1 << HASH_BITS];
 };
 
-extern struct sqlhist_bison *sb;
-
 #include "sqlhist.tab.h"
 
 enum filter_type {
diff --git a/src/sqlhist.l b/src/sqlhist.l
index 476f7fd1f1ec..958c46051148 100644
--- a/src/sqlhist.l
+++ b/src/sqlhist.l
@@ -4,21 +4,26 @@
 #include <stdarg.h>
 #include "sqlhist-parse.h"
 
-extern int my_yyinput(char *buf, int max);
+extern int my_yyinput(void *extra, char *buf, int max);
 
 #undef YY_INPUT
-#define YY_INPUT(b, r, m) ({r = my_yyinput(b, m);})
+#define YY_INPUT(b, r, m) ({r = my_yyinput(yyextra, b, m);})
 
 #define YY_NO_INPUT
 #define YY_NO_UNPUT
 
 #define YY_EXTRA_TYPE struct sqlhist_bison *
 
-#define HANDLE_COLUMN do { sb->line_idx += strlen(yytext); } while (0)
+#define yytext yyg->yytext_r
+
+#define TRACE_SB	((struct sqlhist_bison *)yyextra)
+#define HANDLE_COLUMN do { TRACE_SB->line_idx += strlen(yytext); } while (0)
 
 %}
 
 %option caseless
+%option reentrant
+%option bison-bridge
 
 field		[a-z_][a-z0-9_\.]*
 qstring		\"[^\"]*\"
@@ -36,25 +41,25 @@ where { HANDLE_COLUMN; return WHERE; }
 
 {qstring} {
 	HANDLE_COLUMN;
-	yylval.string = store_str(sb, yytext);
+	yylval->string = store_str(TRACE_SB, yyg->yytext_r);
 	return STRING;
 }
 
 {field} {
 	HANDLE_COLUMN;
-	yylval.string = store_str(sb, yytext);
+	yylval->string = store_str(TRACE_SB, yyg->yytext_r);
 	return FIELD;
 }
 
 {hexnum} {
 	HANDLE_COLUMN;
-	yylval.number = strtol(yytext, NULL, 0);
+	yylval->number = strtol(yyg->yytext_r, NULL, 0);
 	return NUMBER;
 }
 
 {number} {
 	HANDLE_COLUMN;
-	yylval.number = strtol(yytext, NULL, 0);
+	yylval->number = strtol(yyg->yytext_r, NULL, 0);
 	return NUMBER;
 }
 
@@ -69,18 +74,19 @@ where { HANDLE_COLUMN; return WHERE; }
 [\!()\-\+\*/,=] { HANDLE_COLUMN; return yytext[0]; }
 
 [ \t] { HANDLE_COLUMN; }
-\n { sb->line_idx = 0; sb->line_no++; }
+\n { TRACE_SB->line_idx = 0; TRACE_SB->line_no++; }
 
 . { HANDLE_COLUMN; return PARSE_ERROR; }
 %%
 
-int yywrap(void)
+int yywrap(void *data)
 {
 	return 1;
 }
 
-void yyerror(const char *fmt, ...)
+void yyerror(struct sqlhist_bison *sb, char *fmt, ...)
 {
+	struct yyguts_t * yyg = (struct yyguts_t*)sb->scanner;
 	va_list ap;
 
 	va_start(ap, fmt);
diff --git a/src/sqlhist.y b/src/sqlhist.y
index 8dcc824bb9f1..ce9cb58fb3a9 100644
--- a/src/sqlhist.y
+++ b/src/sqlhist.y
@@ -6,8 +6,10 @@
 
 #include "sqlhist-parse.h"
 
-extern int yylex(void);
-extern void yyerror(char *fmt, ...);
+#define scanner sb->scanner
+
+extern int yylex(YYSTYPE *yylval, void *);
+extern void yyerror(struct sqlhist_bison *, char *fmt, ...);
 
 #define CHECK_RETURN_PTR(x)					\
 	do {							\
@@ -27,6 +29,10 @@ extern void yyerror(char *fmt, ...);
 
 %}
 
+%define api.pure
+%lex-param {void *scanner}
+%parse-param {struct sqlhist_bison *sb}
+
 %union {
 	int	s32;
 	char	*string;
diff --git a/src/tracefs-sqlhist.c b/src/tracefs-sqlhist.c
index e47bc57c5add..e8f77d60659f 100644
--- a/src/tracefs-sqlhist.c
+++ b/src/tracefs-sqlhist.c
@@ -14,8 +14,6 @@
 #include "tracefs-local.h"
 #include "sqlhist-parse.h"
 
-struct sqlhist_bison *sb;
-
 extern int yylex_init(void* ptr_yy_globals);
 extern int yylex_init_extra(struct sqlhist_bison *sb, void* ptr_yy_globals);
 extern int yylex_destroy (void * yyscanner );
@@ -98,8 +96,10 @@ struct sql_table {
 	struct expr		**next_selection;
 };
 
-__hidden int my_yyinput(char *buf, int max)
+__hidden int my_yyinput(void *extra, char *buf, int max)
 {
+	struct sqlhist_bison *sb = extra;
+
 	if (!sb || !sb->buffer)
 		return -1;
 
@@ -284,7 +284,8 @@ static struct expr *find_field(struct sqlhist_bison *sb,
 	return NULL;
 }
 
-static void *create_expr(enum expr_type type, struct expr **expr_p)
+static void *create_expr(struct sqlhist_bison *sb,
+			 enum expr_type type, struct expr **expr_p)
 {
 	struct expr *expr;
 
@@ -313,7 +314,7 @@ static void *create_expr(enum expr_type type, struct expr **expr_p)
 
 #define __create_expr(var, type, ENUM, expr)			\
 	do {							\
-		var = (type *)create_expr(EXPR_##ENUM, expr);	\
+		var = (type *)create_expr(sb, EXPR_##ENUM, expr);	\
 	} while(0)
 
 #define create_field(var, expr)				\
@@ -999,8 +1000,8 @@ static void free_sb(struct sqlhist_bison *sb)
 struct tracefs_synth *tracefs_sql(struct tep_handle *tep, const char *name,
 				  const char *sql_buffer, char **err)
 {
-	struct sqlhist_bison local_sb;
 	struct tracefs_synth *synth = NULL;
+	struct sqlhist_bison sb;
 	int ret;
 
 	if (!tep || !sql_buffer) {
@@ -1008,27 +1009,33 @@ struct tracefs_synth *tracefs_sql(struct tep_handle *tep, const char *name,
 		return NULL;
 	}
 
-	memset(&local_sb, 0, sizeof(local_sb));
+	memset(&sb, 0, sizeof(sb));
+
+	sb.buffer = sql_buffer;
+	sb.buffer_size = strlen(sql_buffer);
+	sb.buffer_idx = 0;
 
-	local_sb.buffer = sql_buffer;
-	local_sb.buffer_size = strlen(sql_buffer);
-	local_sb.buffer_idx = 0;
+	ret = yylex_init_extra(&sb, &sb.scanner);
+	if (ret < 0) {
+		yylex_destroy(sb.scanner);
+		return NULL;
+	}
 
-	sb = &local_sb;
-	ret = yyparse();
+	ret = yyparse(&sb);
+	yylex_destroy(sb.scanner);
 
 	if (ret)
 		goto free;
 
-	synth = build_synth(tep, name, sb->table);
+	synth = build_synth(tep, name, sb.table);
 
  free:
 	if (!synth) {
-		if (sb->parse_error_str && err) {
-			*err = sb->parse_error_str;
-			sb->parse_error_str = NULL;
+		if (sb.parse_error_str && err) {
+			*err = sb.parse_error_str;
+			sb.parse_error_str = NULL;
 		}
 	}
-	free_sb(sb);
+	free_sb(&sb);
 	return synth;
 }
-- 
2.30.2


^ permalink raw reply	[flat|nested] 26+ messages in thread

* [PATCH 08/17] libtracefs: Make parser unique to libtracefs
  2021-07-30 22:18 [PATCH 00/17] libtracefs: Introducing tracefs_sql() to create synthetice events with an SQL line Steven Rostedt
                   ` (6 preceding siblings ...)
  2021-07-30 22:18 ` [PATCH 07/17] libtracefs: Make sqlhist parser reentrant Steven Rostedt
@ 2021-07-30 22:18 ` Steven Rostedt
  2021-07-30 22:18 ` [PATCH 09/17] libtracefs: Add line number and index to expr structure Steven Rostedt
                   ` (9 subsequent siblings)
  17 siblings, 0 replies; 26+ messages in thread
From: Steven Rostedt @ 2021-07-30 22:18 UTC (permalink / raw)
  To: linux-trace-devel
  Cc: linux-kernel, Tom Zanussi, Daniel Bristot de Oliveira,
	Masami Hiramatsu, Namhyung Kim, linux-rt-users, Clark Williams,
	Steven Rostedt (VMware)

From: "Steven Rostedt (VMware)" <rostedt@goodmis.org>

Add %define api.prefix and defines to have the parser global variables use
tracefs_* instead of yy*, as without this, if a tool that links to this
library, and tries to use the synth sql parsing, it may end up using its
own yyparse() and friends functions.

Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
---
 src/sqlhist.y         | 10 ++++++++++
 src/tracefs-sqlhist.c |  2 +-
 2 files changed, 11 insertions(+), 1 deletion(-)

diff --git a/src/sqlhist.y b/src/sqlhist.y
index ce9cb58fb3a9..9d03a457ae84 100644
--- a/src/sqlhist.y
+++ b/src/sqlhist.y
@@ -30,6 +30,16 @@ extern void yyerror(struct sqlhist_bison *, char *fmt, ...);
 %}
 
 %define api.pure
+
+/* Change the globals to use tracefs_ prefix */
+%define api.prefix{tracefs_}
+%code provides
+{
+  #define YYSTYPE TRACEFS_STYPE
+  #define yylex tracefs_lex
+  #define yyerror tracefs_error
+}
+
 %lex-param {void *scanner}
 %parse-param {struct sqlhist_bison *sb}
 
diff --git a/src/tracefs-sqlhist.c b/src/tracefs-sqlhist.c
index e8f77d60659f..933b3609733b 100644
--- a/src/tracefs-sqlhist.c
+++ b/src/tracefs-sqlhist.c
@@ -1021,7 +1021,7 @@ struct tracefs_synth *tracefs_sql(struct tep_handle *tep, const char *name,
 		return NULL;
 	}
 
-	ret = yyparse(&sb);
+	ret = tracefs_parse(&sb);
 	yylex_destroy(sb.scanner);
 
 	if (ret)
-- 
2.30.2


^ permalink raw reply	[flat|nested] 26+ messages in thread

* [PATCH 09/17] libtracefs: Add line number and index to expr structure
  2021-07-30 22:18 [PATCH 00/17] libtracefs: Introducing tracefs_sql() to create synthetice events with an SQL line Steven Rostedt
                   ` (7 preceding siblings ...)
  2021-07-30 22:18 ` [PATCH 08/17] libtracefs: Make parser unique to libtracefs Steven Rostedt
@ 2021-07-30 22:18 ` Steven Rostedt
  2021-07-30 22:18 ` [PATCH 10/17] libtracefs: Add a parse_error() helper function to record errors Steven Rostedt
                   ` (8 subsequent siblings)
  17 siblings, 0 replies; 26+ messages in thread
From: Steven Rostedt @ 2021-07-30 22:18 UTC (permalink / raw)
  To: linux-trace-devel
  Cc: linux-kernel, Tom Zanussi, Daniel Bristot de Oliveira,
	Masami Hiramatsu, Namhyung Kim, linux-rt-users, Clark Williams,
	Steven Rostedt (VMware)

From: "Steven Rostedt (VMware)" <rostedt@goodmis.org>

In order to have better error messages, record the line number and index
when an expr structure is created. Then this can be used to show where in
the SQL sequence a problem was found if the building of the synth event
has issues.

Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
---
 src/tracefs-sqlhist.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/src/tracefs-sqlhist.c b/src/tracefs-sqlhist.c
index 933b3609733b..887c2441a39e 100644
--- a/src/tracefs-sqlhist.c
+++ b/src/tracefs-sqlhist.c
@@ -72,6 +72,8 @@ struct expr {
 	struct expr		*free_list;
 	struct expr		*next;
 	enum expr_type		type;
+	int			line;
+	int			idx;
 	union {
 		struct field	field;
 		struct filter	filter;
@@ -300,6 +302,8 @@ static void *create_expr(struct sqlhist_bison *sb,
 	sb->table->exprs = expr;
 
 	expr->type = type;
+	expr->line = sb->line_no;
+	expr->idx = sb->line_idx;
 
 	switch (type) {
 	case EXPR_FIELD:	return &expr->field;
-- 
2.30.2


^ permalink raw reply	[flat|nested] 26+ messages in thread

* [PATCH 10/17] libtracefs: Add a parse_error() helper function to record errors
  2021-07-30 22:18 [PATCH 00/17] libtracefs: Introducing tracefs_sql() to create synthetice events with an SQL line Steven Rostedt
                   ` (8 preceding siblings ...)
  2021-07-30 22:18 ` [PATCH 09/17] libtracefs: Add line number and index to expr structure Steven Rostedt
@ 2021-07-30 22:18 ` Steven Rostedt
  2021-07-30 22:18 ` [PATCH 11/17] libtracefs: Add error message when match fields are not FROM and JOIN events Steven Rostedt
                   ` (7 subsequent siblings)
  17 siblings, 0 replies; 26+ messages in thread
From: Steven Rostedt @ 2021-07-30 22:18 UTC (permalink / raw)
  To: linux-trace-devel
  Cc: linux-kernel, Tom Zanussi, Daniel Bristot de Oliveira,
	Masami Hiramatsu, Namhyung Kim, linux-rt-users, Clark Williams,
	Steven Rostedt (VMware)

From: "Steven Rostedt (VMware)" <rostedt@goodmis.org>

Add parse_error() that calls into sql_parse_error() with the appropriate
ap argument. That is, parse_error() takes a normal printf() form and then
translates it to the vprintf from of sql_parse_error.

Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
---
 src/tracefs-sqlhist.c | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/src/tracefs-sqlhist.c b/src/tracefs-sqlhist.c
index 887c2441a39e..c0875d630391 100644
--- a/src/tracefs-sqlhist.c
+++ b/src/tracefs-sqlhist.c
@@ -8,6 +8,7 @@
  */
 #include <trace-seq.h>
 #include <stdlib.h>
+#include <stdarg.h>
 #include <errno.h>
 
 #include "tracefs.h"
@@ -153,6 +154,16 @@ __hidden void sql_parse_error(struct sqlhist_bison *sb, const char *text,
 	trace_seq_destroy(&s);
 }
 
+static void parse_error(struct sqlhist_bison *sb, const char *text,
+			const char *fmt, ...)
+{
+	va_list ap;
+
+	va_start(ap, fmt);
+	sql_parse_error(sb, text, fmt, ap);
+	va_end(ap);
+}
+
 static inline unsigned int quick_hash(const char *str)
 {
 	unsigned int val = 0;
-- 
2.30.2


^ permalink raw reply	[flat|nested] 26+ messages in thread

* [PATCH 11/17] libtracefs: Add error message when match fields are not FROM and JOIN events
  2021-07-30 22:18 [PATCH 00/17] libtracefs: Introducing tracefs_sql() to create synthetice events with an SQL line Steven Rostedt
                   ` (9 preceding siblings ...)
  2021-07-30 22:18 ` [PATCH 10/17] libtracefs: Add a parse_error() helper function to record errors Steven Rostedt
@ 2021-07-30 22:18 ` Steven Rostedt
  2021-07-30 22:18 ` [PATCH 12/17] libtracefs: Add error message when match or init fails from bad events Steven Rostedt
                   ` (6 subsequent siblings)
  17 siblings, 0 replies; 26+ messages in thread
From: Steven Rostedt @ 2021-07-30 22:18 UTC (permalink / raw)
  To: linux-trace-devel
  Cc: linux-kernel, Tom Zanussi, Daniel Bristot de Oliveira,
	Masami Hiramatsu, Namhyung Kim, linux-rt-users, Clark Williams,
	Steven Rostedt (VMware)

From: "Steven Rostedt (VMware)" <rostedt@goodmis.org>

It is required that the "match" content (the ON portion of the SQL
sequence) has a field from the FROM event and a field from the JOIN event.

If they do not, then give a better message about what went wrong.

Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
---
 src/tracefs-sqlhist.c | 32 ++++++++++++++++++++++++++++++--
 1 file changed, 30 insertions(+), 2 deletions(-)

diff --git a/src/tracefs-sqlhist.c b/src/tracefs-sqlhist.c
index c0875d630391..0489657bea03 100644
--- a/src/tracefs-sqlhist.c
+++ b/src/tracefs-sqlhist.c
@@ -593,6 +593,34 @@ static int update_vars(struct sql_table *table, struct field *event)
 	return 0;
 }
 
+static int match_error(struct sqlhist_bison *sb, struct match *match,
+		       struct field *lmatch, struct field *rmatch)
+{
+	struct field *lval = &match->lval->field;
+	struct field *rval = &match->rval->field;
+	struct field *field;
+	struct expr *expr;
+
+	if (lval->system != lmatch->system ||
+	    lval->event != lmatch->event) {
+		expr = match->lval;
+		field = lval;
+	} else {
+		expr = match->rval;
+		field = rval;
+	}
+
+	sb->line_no = expr->line;
+	sb->line_idx = expr->idx;
+
+	parse_error(sb, field->raw,
+		    "'%s' and '%s' must be a field for each event: '%s' and '%s'\n",
+		    lval->raw, rval->raw, sb->table->to->field.raw,
+		    sb->table->from->field.raw);
+
+	return -1;
+}
+
 static int test_match(struct sql_table *table, struct match *match)
 {
 	struct field *lval, *rval;
@@ -624,13 +652,13 @@ static int test_match(struct sql_table *table, struct match *match)
 		    (rval->event != to->event) ||
 		    (lval->system != from->system) ||
 		    (lval->event != from->event))
-			return -1;
+			return match_error(table->sb, match, from, to);
 	} else {
 		if ((rval->system != from->system) ||
 		    (rval->event != from->event) ||
 		    (lval->system != to->system) ||
 		    (lval->event != to->event))
-			return -1;
+			return match_error(table->sb, match, to, from);
 	}
 	return 0;
 }
-- 
2.30.2


^ permalink raw reply	[flat|nested] 26+ messages in thread

* [PATCH 12/17] libtracefs: Add error message when match or init fails from bad events
  2021-07-30 22:18 [PATCH 00/17] libtracefs: Introducing tracefs_sql() to create synthetice events with an SQL line Steven Rostedt
                   ` (10 preceding siblings ...)
  2021-07-30 22:18 ` [PATCH 11/17] libtracefs: Add error message when match fields are not FROM and JOIN events Steven Rostedt
@ 2021-07-30 22:18 ` Steven Rostedt
  2021-07-30 22:18 ` [PATCH 13/17] libtracefs; Add error message for bad selections to SQL sequence Steven Rostedt
                   ` (5 subsequent siblings)
  17 siblings, 0 replies; 26+ messages in thread
From: Steven Rostedt @ 2021-07-30 22:18 UTC (permalink / raw)
  To: linux-trace-devel
  Cc: linux-kernel, Tom Zanussi, Daniel Bristot de Oliveira,
	Masami Hiramatsu, Namhyung Kim, linux-rt-users, Clark Williams,
	Steven Rostedt (VMware)

From: "Steven Rostedt (VMware)" <rostedt@goodmis.org>

If the tracefs_synth_init() or the matching fails due to events that do
not exist, or if the match fields are not compatible with each other. Add
an error message that reports this and where the problem is.

Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
---
 src/tracefs-sqlhist.c | 101 +++++++++++++++++++++++++++++++++++++++++-
 1 file changed, 99 insertions(+), 2 deletions(-)

diff --git a/src/tracefs-sqlhist.c b/src/tracefs-sqlhist.c
index 0489657bea03..d39851845570 100644
--- a/src/tracefs-sqlhist.c
+++ b/src/tracefs-sqlhist.c
@@ -876,6 +876,101 @@ static int build_filter(struct tracefs_synth *synth,
 	return ret;
 }
 
+static int test_event_exists(struct tep_handle *tep, struct sqlhist_bison *sb,
+			     struct expr *expr, struct tep_event **pevent)
+{
+	const char *system = expr->field.system;
+	const char *event_name = expr->field.event;
+	struct tep_event *event;
+
+	event = tep_find_event_by_name(tep, system, event_name);
+	if (pevent)
+		*pevent = event;
+	if (event)
+		return 0;
+
+	sb->line_no = expr->line;
+	sb->line_idx = expr->idx;
+
+	parse_error(sb, expr->field.raw, "event not found\n");
+	return -1;
+}
+
+static int test_field_exists(struct tep_handle *tep, struct sqlhist_bison *sb,
+			     struct expr *expr)
+{
+	struct tep_event *event;
+
+	if (test_event_exists(tep, sb, expr, &event))
+		return -1;
+
+	if (trace_verify_event_field(event, expr->field.field, NULL))
+		return 0;
+
+	sb->line_no = expr->line;
+	sb->line_idx = expr->idx;
+
+	parse_error(sb, expr->field.raw, "Field '%s' not part of event %s\n",
+		    expr->field.field, expr->field.event);
+	return -1;
+}
+
+static void *field_match_error(struct tep_handle *tep, struct sqlhist_bison *sb,
+			       struct match *match)
+{
+	switch (errno) {
+	case ENODEV:
+	case EBADE:
+		break;
+	default:
+		/* System error */
+		return NULL;
+	}
+
+	/* ENODEV means that an event or field does not exist */
+	if (errno == ENODEV) {
+		if (test_field_exists(tep, sb, match->lval))
+			return NULL;
+		if (test_field_exists(tep, sb, match->rval))
+			return NULL;
+		return NULL;
+	}
+
+	/* fields exist, but values are not compatible */
+	sb->line_no = match->lval->line;
+	sb->line_idx = match->lval->idx;
+
+	parse_error(sb, match->lval->field.raw,
+		    "Field '%s' is not compatible to match field '%s'\n",
+		    match->lval->field.raw, match->rval->field.raw);
+	return NULL;
+}
+
+static void *synth_init_error(struct tep_handle *tep, struct sql_table *table)
+{
+	struct sqlhist_bison *sb = table->sb;
+	struct match *match = table->matches;
+
+	switch (errno) {
+	case ENODEV:
+	case EBADE:
+		break;
+	default:
+		/* System error */
+		return NULL;
+	}
+
+	/* ENODEV could mean that start or end events do not exist */
+	if (errno == ENODEV) {
+		if (test_event_exists(tep, sb, table->from, NULL))
+			return NULL;
+		if (test_event_exists(tep, sb, table->to, NULL))
+			return NULL;
+	}
+
+	return field_match_error(tep, sb, match);
+}
+
 static struct tracefs_synth *build_synth(struct tep_handle *tep,
 					 const char *name,
 					 struct sql_table *table)
@@ -926,7 +1021,7 @@ static struct tracefs_synth *build_synth(struct tep_handle *tep,
 				   start_event, end_system, end_event,
 				   start_match, end_match, NULL);
 	if (!synth)
-		return NULL;
+		return synth_init_error(tep, table);
 
 	for (match = match->next; match; match = match->next) {
 		ret = test_match(table, match);
@@ -939,8 +1034,10 @@ static struct tracefs_synth *build_synth(struct tep_handle *tep,
 		ret = tracefs_synth_add_match_field(synth,
 						    start_match,
 						    end_match, NULL);
-		if (ret < 0)
+		if (ret < 0) {
+			field_match_error(tep, table->sb, match);
 			goto free;
+		}
 	}
 
 	for (expr = table->selections; expr; expr = expr->next) {
-- 
2.30.2


^ permalink raw reply	[flat|nested] 26+ messages in thread

* [PATCH 13/17] libtracefs; Add error message for bad selections to SQL sequence
  2021-07-30 22:18 [PATCH 00/17] libtracefs: Introducing tracefs_sql() to create synthetice events with an SQL line Steven Rostedt
                   ` (11 preceding siblings ...)
  2021-07-30 22:18 ` [PATCH 12/17] libtracefs: Add error message when match or init fails from bad events Steven Rostedt
@ 2021-07-30 22:18 ` Steven Rostedt
  2021-07-30 22:18 ` [PATCH 14/17] libtracefs: Add error message when compare fields fail Steven Rostedt
                   ` (4 subsequent siblings)
  17 siblings, 0 replies; 26+ messages in thread
From: Steven Rostedt @ 2021-07-30 22:18 UTC (permalink / raw)
  To: linux-trace-devel
  Cc: linux-kernel, Tom Zanussi, Daniel Bristot de Oliveira,
	Masami Hiramatsu, Namhyung Kim, linux-rt-users, Clark Williams,
	Steven Rostedt (VMware)

From: "Steven Rostedt (VMware)" <rostedt@goodmis.org>

If the building of the synthetic event fails on creating the selection,
report it properly.

Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
---
 src/tracefs-sqlhist.c | 14 +++++++++++++-
 1 file changed, 13 insertions(+), 1 deletion(-)

diff --git a/src/tracefs-sqlhist.c b/src/tracefs-sqlhist.c
index d39851845570..e542eb95c17f 100644
--- a/src/tracefs-sqlhist.c
+++ b/src/tracefs-sqlhist.c
@@ -971,6 +971,16 @@ static void *synth_init_error(struct tep_handle *tep, struct sql_table *table)
 	return field_match_error(tep, sb, match);
 }
 
+static void selection_error(struct tep_handle *tep,
+			    struct sqlhist_bison *sb, struct expr *expr)
+{
+	/* We just care about event not existing */
+	if (errno != ENODEV)
+		return;
+
+	test_field_exists(tep, sb, expr);
+}
+
 static struct tracefs_synth *build_synth(struct tep_handle *tep,
 					 const char *name,
 					 struct sql_table *table)
@@ -1051,8 +1061,10 @@ static struct tracefs_synth *build_synth(struct tep_handle *tep,
 				ret = tracefs_synth_add_end_field(synth,
 						field->field, field->label);
 			}
-			if (ret < 0)
+			if (ret < 0) {
+				selection_error(tep, table->sb, expr);
 				goto free;
+			}
 			continue;
 		}
 
-- 
2.30.2


^ permalink raw reply	[flat|nested] 26+ messages in thread

* [PATCH 14/17] libtracefs: Add error message when compare fields fail
  2021-07-30 22:18 [PATCH 00/17] libtracefs: Introducing tracefs_sql() to create synthetice events with an SQL line Steven Rostedt
                   ` (12 preceding siblings ...)
  2021-07-30 22:18 ` [PATCH 13/17] libtracefs; Add error message for bad selections to SQL sequence Steven Rostedt
@ 2021-07-30 22:18 ` Steven Rostedt
  2021-07-30 22:18 ` [PATCH 15/17] libtracefs: Add error message for grouping events in SQL filter Steven Rostedt
                   ` (3 subsequent siblings)
  17 siblings, 0 replies; 26+ messages in thread
From: Steven Rostedt @ 2021-07-30 22:18 UTC (permalink / raw)
  To: linux-trace-devel
  Cc: linux-kernel, Tom Zanussi, Daniel Bristot de Oliveira,
	Masami Hiramatsu, Namhyung Kim, linux-rt-users, Clark Williams,
	Steven Rostedt (VMware)

From: "Steven Rostedt (VMware)" <rostedt@goodmis.org>

If the processing of comparing fields fail due to not existing or because
they are not compatible to compare, report a proper error message.

Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
---
 src/tracefs-sqlhist.c | 36 +++++++++++++++++++++++++++++++++++-
 1 file changed, 35 insertions(+), 1 deletion(-)

diff --git a/src/tracefs-sqlhist.c b/src/tracefs-sqlhist.c
index e542eb95c17f..ff0869232a9e 100644
--- a/src/tracefs-sqlhist.c
+++ b/src/tracefs-sqlhist.c
@@ -981,6 +981,38 @@ static void selection_error(struct tep_handle *tep,
 	test_field_exists(tep, sb, expr);
 }
 
+static void compare_error(struct tep_handle *tep,
+			    struct sqlhist_bison *sb, struct expr *expr)
+{
+	struct compare *compare = &expr->compare;
+
+	switch (errno) {
+	case ENODEV:
+	case EBADE:
+		break;
+	default:
+		/* System error */
+		return;
+	}
+
+	/* ENODEV means that an event or field does not exist */
+	if (errno == ENODEV) {
+		if (test_field_exists(tep, sb, compare->lval))
+			return;
+		if (test_field_exists(tep, sb, compare->rval))
+			return;
+		return;
+	}
+
+	/* fields exist, but values are not compatible */
+	sb->line_no = compare->lval->line;
+	sb->line_idx = compare->lval->idx;
+
+	parse_error(sb, compare->lval->field.raw,
+		    "'%s' is not compatible to compare with '%s'\n",
+		    compare->lval->field.raw, compare->rval->field.raw);
+}
+
 static struct tracefs_synth *build_synth(struct tep_handle *tep,
 					 const char *name,
 					 struct sql_table *table)
@@ -1073,8 +1105,10 @@ static struct tracefs_synth *build_synth(struct tep_handle *tep,
 
 		ret = build_compare(synth, start_system, end_system,
 				    &expr->compare);
-		if (ret < 0)
+		if (ret < 0) {
+			compare_error(tep, table->sb, expr);
 			goto free;
+		}
 	}
 
 	for (expr = table->where; expr; expr = expr->next) {
-- 
2.30.2


^ permalink raw reply	[flat|nested] 26+ messages in thread

* [PATCH 15/17] libtracefs: Add error message for grouping events in SQL filter
  2021-07-30 22:18 [PATCH 00/17] libtracefs: Introducing tracefs_sql() to create synthetice events with an SQL line Steven Rostedt
                   ` (13 preceding siblings ...)
  2021-07-30 22:18 ` [PATCH 14/17] libtracefs: Add error message when compare fields fail Steven Rostedt
@ 2021-07-30 22:18 ` Steven Rostedt
  2021-07-30 22:18 ` [PATCH 16/17] libtracefs: Add error message for bad filters in SQL statement Steven Rostedt
                   ` (2 subsequent siblings)
  17 siblings, 0 replies; 26+ messages in thread
From: Steven Rostedt @ 2021-07-30 22:18 UTC (permalink / raw)
  To: linux-trace-devel
  Cc: linux-kernel, Tom Zanussi, Daniel Bristot de Oliveira,
	Masami Hiramatsu, Namhyung Kim, linux-rt-users, Clark Williams,
	Steven Rostedt (VMware)

From: "Steven Rostedt (VMware)" <rostedt@goodmis.org>

One requirement for the SQL filter in tracefs_sql() is that the WHERE
clause (filter) can only filter the FROM and JOIN events with "&&".

That is, you can not have:

  sched_switch.next_pid == 0 || sched_waking.pid == 0

As the filtering one event stops the synthetic event, having an ||
conjunction makes no sense.

Add an error message that explains this when it is found.

Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
---
 src/tracefs-sqlhist.c | 35 +++++++++++++++++++++++++----------
 1 file changed, 25 insertions(+), 10 deletions(-)

diff --git a/src/tracefs-sqlhist.c b/src/tracefs-sqlhist.c
index ff0869232a9e..1767c33d77d0 100644
--- a/src/tracefs-sqlhist.c
+++ b/src/tracefs-sqlhist.c
@@ -715,21 +715,36 @@ static int build_compare(struct tracefs_synth *synth,
 	return ret;
 }
 
-static int do_verify_filter(struct filter *filter,
+static int verify_filter_error(struct sqlhist_bison *sb, struct expr *expr,
+			       const char *event)
+{
+	struct field *field = &expr->field;
+
+	sb->line_no = expr->line;
+	sb->line_idx = expr->idx;
+
+	parse_error(sb, field->raw,
+		    "event '%s' can not be grouped or '||' together with '%s'\n"
+		    "All filters between '&&' must be for the same event\n",
+		    field->event, event);
+	return -1;
+}
+
+static int do_verify_filter(struct sqlhist_bison *sb, struct filter *filter,
 			    const char **system, const char **event)
 {
 	int ret;
 
 	if (filter->type == FILTER_OR ||
 	    filter->type == FILTER_AND) {
-		ret = do_verify_filter(&filter->lval->filter, system, event);
+		ret = do_verify_filter(sb, &filter->lval->filter, system, event);
 		if (ret)
 			return ret;
-		return do_verify_filter(&filter->rval->filter, system, event);
+		return do_verify_filter(sb, &filter->rval->filter, system, event);
 	}
 	if (filter->type == FILTER_GROUP ||
 	    filter->type == FILTER_NOT_GROUP) {
-		return do_verify_filter(&filter->lval->filter, system, event);
+		return do_verify_filter(sb, &filter->lval->filter, system, event);
 	}
 
 	/*
@@ -744,12 +759,12 @@ static int do_verify_filter(struct filter *filter,
 
 	if (filter->lval->field.system != *system ||
 	    filter->lval->field.event != *event)
-		return -1;
+		return verify_filter_error(sb, filter->lval, *event);
 
 	return 0;
 }
 
-static int verify_filter(struct filter *filter,
+static int verify_filter(struct sqlhist_bison *sb, struct filter *filter,
 			 const char **system, const char **event)
 {
 	int ret;
@@ -761,17 +776,17 @@ static int verify_filter(struct filter *filter,
 	case FILTER_NOT_GROUP:
 		break;
 	default:
-		return do_verify_filter(filter, system, event);
+		return do_verify_filter(sb, filter, system, event);
 	}
 
-	ret = do_verify_filter(&filter->lval->filter, system, event);
+	ret = do_verify_filter(sb, &filter->lval->filter, system, event);
 	if (ret)
 		return ret;
 
 	switch (filter->type) {
 	case FILTER_OR:
 	case FILTER_AND:
-		return do_verify_filter(&filter->rval->filter, system, event);
+		return do_verify_filter(sb, &filter->rval->filter, system, event);
 	default:
 		return 0;
 	}
@@ -1117,7 +1132,7 @@ static struct tracefs_synth *build_synth(struct tep_handle *tep,
 		bool *started;
 		bool start;
 
-		ret = verify_filter(&expr->filter, &filter_system,
+		ret = verify_filter(table->sb, &expr->filter, &filter_system,
 				    &filter_event);
 		if (ret < 0)
 			goto free;
-- 
2.30.2


^ permalink raw reply	[flat|nested] 26+ messages in thread

* [PATCH 16/17] libtracefs: Add error message for bad filters in SQL statement
  2021-07-30 22:18 [PATCH 00/17] libtracefs: Introducing tracefs_sql() to create synthetice events with an SQL line Steven Rostedt
                   ` (14 preceding siblings ...)
  2021-07-30 22:18 ` [PATCH 15/17] libtracefs: Add error message for grouping events in SQL filter Steven Rostedt
@ 2021-07-30 22:18 ` Steven Rostedt
  2021-07-30 22:18 ` [PATCH 17/17] libtracefs: Add man page for tracefs_sql() Steven Rostedt
  2021-07-30 22:31 ` [PATCH 00/17] libtracefs: Introducing tracefs_sql() to create synthetice events with an SQL line Steven Rostedt
  17 siblings, 0 replies; 26+ messages in thread
From: Steven Rostedt @ 2021-07-30 22:18 UTC (permalink / raw)
  To: linux-trace-devel
  Cc: linux-kernel, Tom Zanussi, Daniel Bristot de Oliveira,
	Masami Hiramatsu, Namhyung Kim, linux-rt-users, Clark Williams,
	Steven Rostedt (VMware)

From: "Steven Rostedt (VMware)" <rostedt@goodmis.org>

If a filter has a bad event, or incompatibility with the value assigned to
it, have the error message display it.

Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
---
 src/tracefs-sqlhist.c | 80 +++++++++++++++++++++++++++++++++++++++----
 1 file changed, 74 insertions(+), 6 deletions(-)

diff --git a/src/tracefs-sqlhist.c b/src/tracefs-sqlhist.c
index 1767c33d77d0..f191661610c9 100644
--- a/src/tracefs-sqlhist.c
+++ b/src/tracefs-sqlhist.c
@@ -792,14 +792,80 @@ static int verify_filter(struct sqlhist_bison *sb, struct filter *filter,
 	}
 }
 
-static int build_filter(struct tracefs_synth *synth,
-			bool start, struct filter *filter, bool *started)
+static int test_field_exists(struct tep_handle *tep, struct sqlhist_bison *sb,
+			     struct expr *expr);
+
+static void filter_compare_error(struct tep_handle *tep,
+				 struct sqlhist_bison *sb,
+				 struct expr *expr)
+{
+	struct field *field = &expr->field;
+
+	switch (errno) {
+	case ENODEV:
+	case EBADE:
+		break;
+	case EINVAL:
+		parse_error(sb, field->raw, "Invalid compare\n");
+		break;
+	default:
+		parse_error(sb, field->raw, "System error?\n");
+		return;
+	}
+
+	/* ENODEV means that an event or field does not exist */
+	if (errno == ENODEV) {
+		if (test_field_exists(tep, sb, expr))
+			return;
+		if (test_field_exists(tep, sb, expr))
+			return;
+		return;
+	}
+
+	/* fields exist, but values are not compatible */
+	sb->line_no = expr->line;
+	sb->line_idx = expr->idx;
+
+	parse_error(sb, field->raw,
+		    "Field '%s' is not compatible to be compared with the given value\n",
+		    field->field);
+}
+
+static void filter_error(struct tep_handle *tep,
+			 struct sqlhist_bison *sb, struct expr *expr)
+{
+	struct filter *filter = &expr->filter;
+
+	sb->line_no = expr->line;
+	sb->line_idx = expr->idx;
+
+	switch (filter->type) {
+	case FILTER_NOT_GROUP:
+	case FILTER_GROUP:
+	case FILTER_OR:
+	case FILTER_AND:
+		break;
+	default:
+		filter_compare_error(tep, sb, filter->lval);
+		return;
+	}
+
+	sb->line_no = expr->line;
+	sb->line_idx = expr->idx;
+
+	parse_error(sb, "", "Problem with filter entry?\n");
+}
+
+static int build_filter(struct tep_handle *tep, struct sqlhist_bison *sb,
+			struct tracefs_synth *synth,
+			bool start, struct expr *expr, bool *started)
 {
 	int (*append_filter)(struct tracefs_synth *synth,
 			     enum tracefs_filter type,
 			     const char *field,
 			     enum tracefs_compare compare,
 			     const char *val);
+	struct filter *filter = &expr->filter;
 	enum tracefs_compare cmp;
 	const char *val;
 	int and_or = TRACEFS_FILTER_AND;
@@ -829,7 +895,7 @@ static int build_filter(struct tracefs_synth *synth,
 				    NULL, 0, NULL);
 		if (ret < 0)
 			goto out;
-		ret = build_filter(synth, start, &filter->lval->filter, NULL);
+		ret = build_filter(tep, sb, synth, start, filter->lval, NULL);
 		if (ret < 0)
 			goto out;
 		ret = append_filter(synth, TRACEFS_FILTER_CLOSE_PAREN,
@@ -840,14 +906,14 @@ static int build_filter(struct tracefs_synth *synth,
 		and_or = TRACEFS_FILTER_OR;
 		/* Fall through */
 	case FILTER_AND:
-		ret = build_filter(synth, start, &filter->lval->filter, NULL);
+		ret = build_filter(tep, sb, synth, start, filter->lval, NULL);
 		if (ret < 0)
 			goto out;
 		ret = append_filter(synth, and_or, NULL, 0, NULL);
 
 		if (ret)
 			goto out;
-		ret = build_filter(synth, start, &filter->rval->filter, NULL);
+		ret = build_filter(tep, sb, synth, start, filter->rval, NULL);
 		goto out;
 	default:
 		break;
@@ -881,6 +947,8 @@ static int build_filter(struct tracefs_synth *synth,
 	ret = append_filter(synth, TRACEFS_FILTER_COMPARE,
 			    filter->lval->field.field, cmp, val);
 
+	if (ret)
+		filter_error(tep, sb, expr);
  out:
 	if (!ret && started) {
 		if (*started)
@@ -1145,7 +1213,7 @@ static struct tracefs_synth *build_synth(struct tep_handle *tep,
 		else
 			started = &started_end;
 
-		ret = build_filter(synth, start, &expr->filter, started);
+		ret = build_filter(tep, table->sb, synth, start, expr, started);
 		if (ret < 0)
 			goto free;
 	}
-- 
2.30.2


^ permalink raw reply	[flat|nested] 26+ messages in thread

* [PATCH 17/17] libtracefs: Add man page for tracefs_sql()
  2021-07-30 22:18 [PATCH 00/17] libtracefs: Introducing tracefs_sql() to create synthetice events with an SQL line Steven Rostedt
                   ` (15 preceding siblings ...)
  2021-07-30 22:18 ` [PATCH 16/17] libtracefs: Add error message for bad filters in SQL statement Steven Rostedt
@ 2021-07-30 22:18 ` Steven Rostedt
  2021-08-01 13:39   ` Ahmed S. Darwish
  2021-07-30 22:31 ` [PATCH 00/17] libtracefs: Introducing tracefs_sql() to create synthetice events with an SQL line Steven Rostedt
  17 siblings, 1 reply; 26+ messages in thread
From: Steven Rostedt @ 2021-07-30 22:18 UTC (permalink / raw)
  To: linux-trace-devel
  Cc: linux-kernel, Tom Zanussi, Daniel Bristot de Oliveira,
	Masami Hiramatsu, Namhyung Kim, linux-rt-users, Clark Williams,
	Steven Rostedt (VMware)

From: "Steven Rostedt (VMware)" <rostedt@goodmis.org>

Add a man page for tracefs_sql(). Included in that man page is a full
working sql parser example program that can allow you to create synthetic
events from writing SQL on the command line.

Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
---
 Documentation/libtracefs-sql.txt | 367 +++++++++++++++++++++++++++++++
 1 file changed, 367 insertions(+)
 create mode 100644 Documentation/libtracefs-sql.txt

diff --git a/Documentation/libtracefs-sql.txt b/Documentation/libtracefs-sql.txt
new file mode 100644
index 000000000000..e9b3d1ddbc22
--- /dev/null
+++ b/Documentation/libtracefs-sql.txt
@@ -0,0 +1,367 @@
+libtracefs(3)
+=============
+
+NAME
+----
+tracefs_sql - Create a synthetitc event via an SQL statement
+
+SYNOPSIS
+--------
+[verse]
+--
+*#include <tracefs.h>*
+
+struct tracefs_synth *tracefs_sql(struct tep_handle pass:[*]tep, const char pass:[*]name,
+				  const char pass:[*]sql_buffer, char pass:[**]err);
+--
+
+DESCRIPTION
+-----------
+Synthetic events are dynamically created events that attach two existing events
+together via one or more matching fields between the two events. It can be used
+to find the latency between the events, or to simply pass fields of the first event
+on to the second event to display as one event.
+
+The Linux kernel interface to create synthetic events is complex, and there needs
+to be a better way to create synthetic events that is easy and can be understood
+via existing technology.
+
+If you think of each event as a table, where the fields are the column of the table
+and each instance of the event as a row, you can understand how SQL can be used
+to attach two events together and for another event (table). Utilizing the
+SQL *SELECT* *FROM* *JOIN* *ON* [ *WHERE* ] syntax, a synthetic event can easily
+be created from two different events.
+
+
+*tracefs_sql*() takes in a *tep* handler (See _tep_local_events_(3)) that is used to
+verify the events within the _sql_buffer_ expression. The _name_ is the name of the
+synthetic event to create. If _err_ points to an address of a string, it will be filled
+with a detailed message on any type of parsing error, including fields that do not belong
+to an event, or if the events or fields are not properly compared.
+
+The example program below is a fully functional parser where it will create a synthetic
+event from a SQL syntax passed in via the command line or a file. 
+
+The SQL format is as follows:
+
+*SELECT* <fields> FROM <start-event> JOIN <end-event> ON <matching-fields> WHERE <filter>
+
+Note, although the examples show the SQL commands in uppercase, they are not required to
+be so. That is, you can use "SELECT" or "select" or "sElEct".
+
+For example:
+[source,c]
+--
+SELECT syscalls.sys_enter_read.fd, syscalls.sys_exit_read.ret FROM syscalls.sys_enter_read
+   JOIN syscalls.sys_exit_read
+   ON syscalls.sys_enter_read.common_pid = syscalls.sys_exit_write.common_pid
+--
+
+Will create a synthetic event that with the fields:
+
+  u64 fd; s64 ret;
+
+Because the function takes a _tep_ handle, and usually all event names are unique, you can
+leave off the system (group) name of the event, and *tracefs_sql*() will discover the
+system for you.
+
+That is, the above statement would work with:
+
+[source,c]
+--
+SELECT sys_enter_read.fd, sys_exit_read.ret FROM sys_enter_read JOIN sys_exit_read
+   ON sys_enter_read.common_pid = sys_exit_write.common_pid
+--
+
+The *AS* keyword can be used to name the fields as well as to give an alias to the
+events, such that the above can be simplified even more as:
+
+[source,c]
+--
+SELECT start.fd, end.ret FROM sys_enter_read AS start JOIN sys_exit_read AS end ON start.common_pid = end.common_pid
+--
+
+The above aliases _sys_enter_read_ as *start* and _sys_exit_read_ as *end* and uses
+those aliases to reference the event throughout the statement.
+
+Using the *AS* keyword in the selection portion of the SQL statement will define what
+those fields will be called in the synthetic event.
+
+[source,c]
+--
+SELECT start.fd AS filed, end.ret AS return FROM sys_enter_read AS start JOIN sys_exit_read AS end
+   ON start.common_pid = end.common_pid
+--
+
+The above labels the _fd_ of _start_ as *filed* and the _ret_ of _end_ as *return* where
+the synthetic event that is created will now have the fields:
+
+  u64 filed; s64 return;
+
+The fields can also be calculated with results passed to the synthetic event:
+
+[source,c]
+--
+select start.truesize, end.len, (start.truesize - end.len) as diff from napi_gro_receive_entry as start
+   JOIN netif_receive_skb as end ON start.skbaddr = end.skbaddr
+--
+
+Which would show the *truesize" of the _napi_gro_receive_entry_ event, the actual
+_len_ of the content, shown by the _netif_receive_skb_, and alse the delta between
+the two and expressed by the field *diff*.
+
+The code also supports recording the timestamps at either event, and performing calculations
+on them. For wakeup latency, you have:
+
+[source,c]
+--
+select start.pid, (end.TIMESTAMP_USECS - start.TIMESTAMP_USECS) as lat from sched_waking as start
+   JOIN sched_switch as end ON start.pid = end.next_pid
+--
+
+The above will create a synthetic event that records the _pid_ of the task being woken up,
+and the time difference between the _sched_waking_ event and the _sched_switch_ event.
+The *TIMESTAMP_USECS* will truncate the time down to microseconds as the timestamp usually
+recorded in the tracing buffer has nanosecond resolution. If you do not want that
+truncation, use *TIMESTAMP* instead of *TIMESTAMP_USECS*.
+
+Finally, the *WHERE* clause can be added, that will let you add filters on either or both events.
+
+[source,c]
+--
+select start.pid, (end.TIMESTAMP_USECS - start.TIMESTAMP_USECS) as lat from sched_waking as start
+   JOIN sched_switch as end ON start.pid = end.next_pid
+   WHERE start.prio < 100 && (!(end.prev_pid < 1 || end.prev_prio > 100) || end.prev_pid == 0)
+--
+
+*NOTE*
+
+Although both events can be used together in the *WHERE* clause, they must not be mixed outside
+the top most "&&" statements. You can not OR (||) the events together, where a filter of one
+event is OR'd to a filter of the other event. This does not make sense, as the synthetic event
+requires both events to take place to be recorded. If one is filtered out, then the synthetic
+event does not execute.
+
+[source,c]
+--
+select start.pid, (end.TIMESTAMP_USECS - start.TIMESTAMP_USECS) as lat from sched_waking as start
+   JOIN sched_switch as end ON start.pid = end.next_pid
+   WHERE start.prio < 100 && end.prev_prio < 100
+--
+
+The above is valid.
+
+Where as the below is not.
+
+[source,c]
+--
+select start.pid, (end.TIMESTAMP_USECS - start.TIMESTAMP_USECS) as lat from sched_waking as start
+   JOIN sched_switch as end ON start.pid = end.next_pid
+   WHERE start.prio < 100 || end.prev_prio < 100
+--
+
+
+RETURN VALUE
+------------
+Returns 0 on success and -1 on failure. On failure, if _err_ is defined, it will be
+allocated to hold a detailed description of what went wrong if it the error was caused
+by a parsing error, or that an event, field does not exist or is not compatible with
+what it was combined with.
+
+EXAMPLE
+-------
+[source,c]
+--
+#include <stdio.h>
+#include <stdlib.h>
+#include <stdarg.h>
+#include <string.h>
+#include <errno.h>
+#include <unistd.h>
+#include <tracefs.h>
+
+static void usage(char **argv)
+{
+	fprintf(stderr, "usage: %s [-ed][-n name][-t dir][-f file | sql-command-line]\n"
+		"  -n name - name of synthetic event 'Anonymous' if left off\n"
+		"  -t dir - use dir instead of /sys/kernel/tracing\n"
+		"  -e - execute the commands to create the synthetic event\n"
+		"  -d - delete the synthetic event that would be created\n"
+		"  -f file - read sql lines from file otherwise from the command line\n"
+		"            if file is '-' then read from standard input.\n",
+		argv[0]);
+	exit(-1);
+}
+
+static int do_sql(const char *buffer, const char *name,
+		  const char *trace_dir, bool execute)
+{
+	struct tracefs_synth *synth;
+	struct tep_handle *tep;
+	struct trace_seq seq;
+	char *err;
+
+	if (!name)
+		name = "Anonymous";
+
+	trace_seq_init(&seq);
+	tep = tracefs_local_events(trace_dir);
+	if (!tep) {
+		if (!trace_dir)
+			trace_dir = "tracefs directory";
+		perror(trace_dir);
+		exit(-1);
+	}
+
+	synth = tracefs_sql(tep, name, buffer, &err);
+	if (!synth) {
+		perror("Failed creating synthetic event!");
+		if (err)
+			fprintf(stderr, "%s", err);
+		exit(-1);
+	}
+
+	tracefs_synth_show(&seq, NULL, synth);
+	if (execute)
+		tracefs_synth_create(NULL, synth);
+	tracefs_synth_free(synth);
+
+	trace_seq_do_printf(&seq);
+	trace_seq_destroy(&seq);
+	return 0;
+}
+
+int main (int argc, char **argv)
+{
+	char *trace_dir = NULL;
+	char *buffer = NULL;
+	char buf[BUFSIZ];
+	int buffer_size = 0;
+	const char *file = NULL;
+	bool execute = false;
+	const char *name;
+	FILE *fp;
+	size_t r;
+	int c;
+	int i;
+
+	for (;;) {
+		c = getopt(argc, argv, "ht:f:edn:");
+		if (c == -1)
+			break;
+
+		switch(c) {
+		case 'h':
+			usage(argv);
+		case 't':
+			trace_dir = optarg;
+			break;
+		case 'f':
+			file = optarg;
+			break;
+		case 'e':
+			execute = true;
+			break;
+		case 'n':
+			name = optarg;
+			break;
+		}
+	}
+
+	if (file) {
+		if (!strcmp(file, "-"))
+			fp = stdin;
+		else
+			fp = fopen(file, "r");
+		if (!fp) {
+			perror(file);
+			exit(-1);
+		}
+		while ((r = fread(buf, 1, BUFSIZ, fp)) > 0) {
+			buffer = realloc(buffer, buffer_size + r + 1);
+			strncpy(buffer + buffer_size, buf, r);
+			buffer_size += r;
+		}
+		fclose(fp);
+		if (buffer_size)
+			buffer[buffer_size] = '\0';
+	} else if (argc == optind) {
+		usage(argv);
+	} else {
+		for (i = optind; i < argc; i++) {
+			r = strlen(argv[i]);
+			buffer = realloc(buffer, buffer_size + r + 2);
+			if (i != optind)
+				buffer[buffer_size++] = ' ';
+			strcpy(buffer + buffer_size, argv[i]);
+			buffer_size += r;
+		}
+	}
+
+	do_sql(buffer, name, trace_dir, execute);
+	free(buffer);
+
+	return 0;
+}
+--
+
+FILES
+-----
+[verse]
+--
+*tracefs.h*
+	Header file to include in order to have access to the library APIs.
+*-ltracefs*
+	Linker switch to add when building a program that uses the library.
+--
+
+SEE ALSO
+--------
+_libtracefs(3)_,
+_libtraceevent(3)_,
+_trace-cmd(1)_,
+_tracefs_synth_init(3)_,
+_tracefs_synth_add_match_field(3)_,
+_tracefs_synth_add_compare_field(3)_,
+_tracefs_synth_add_start_field(3)_,
+_tracefs_synth_add_end_field(3)_,
+_tracefs_synth_append_start_filter(3)_,
+_tracefs_synth_append_end_filter(3)_,
+_tracefs_synth_create(3)_,
+_tracefs_synth_destroy(3)_,
+_tracefs_synth_free(3)_,
+_tracefs_synth_show(3)_,
+_tracefs_hist_alloc(3)_,
+_tracefs_hist_free(3)_,
+_tracefs_hist_add_key(3)_,
+_tracefs_hist_add_value(3)_,
+_tracefs_hist_add_name(3)_,
+_tracefs_hist_start(3)_,
+_tracefs_hist_destory(3)_,
+_tracefs_hist_add_sort_key(3)_,
+_tracefs_hist_sort_key_direction(3)_
+
+AUTHOR
+------
+[verse]
+--
+*Steven Rostedt* <rostedt@goodmis.org>
+*Tzvetomir Stoyanov* <tz.stoyanov@gmail.com>
+*sameeruddin shaik* <sameeruddin.shaik8@gmail.com>
+--
+REPORTING BUGS
+--------------
+Report bugs to  <linux-trace-devel@vger.kernel.org>
+
+LICENSE
+-------
+libtracefs is Free Software licensed under the GNU LGPL 2.1
+
+RESOURCES
+---------
+https://git.kernel.org/pub/scm/libs/libtrace/libtracefs.git/
+
+COPYING
+-------
+Copyright \(C) 2020 VMware, Inc. Free use of this software is granted under
+the terms of the GNU Public License (GPL).
-- 
2.30.2


^ permalink raw reply	[flat|nested] 26+ messages in thread

* Re: [PATCH 00/17] libtracefs: Introducing tracefs_sql() to create synthetice events with an SQL line
  2021-07-30 22:18 [PATCH 00/17] libtracefs: Introducing tracefs_sql() to create synthetice events with an SQL line Steven Rostedt
                   ` (16 preceding siblings ...)
  2021-07-30 22:18 ` [PATCH 17/17] libtracefs: Add man page for tracefs_sql() Steven Rostedt
@ 2021-07-30 22:31 ` Steven Rostedt
  17 siblings, 0 replies; 26+ messages in thread
From: Steven Rostedt @ 2021-07-30 22:31 UTC (permalink / raw)
  To: linux-trace-devel
  Cc: linux-kernel, Tom Zanussi, Daniel Bristot de Oliveira,
	Masami Hiramatsu, Namhyung Kim, linux-rt-users, Clark Williams

On Fri, 30 Jul 2021 18:18:07 -0400
Steven Rostedt <rostedt@goodmis.org> wrote:

> FUNCTIONAL EXAMPLE:
> -------------------
> 
> After applying this patch, and installing it. If you compile the example from the man
> page (calling it sqlhist.c):
> 
>  >$ gcc -o sqlhist sqlhist.c `pkg-config --cflags --libs libtracefs`
>  >$ su
>  ># ./sqlhist -n syscall_wait -e 'select start.id, (end.TIMESTAMP_USECS - start.TIMESTAMP_USECS) as lat  
>     from sys_enter as start join sys_exit as end on start.common_pid = end.common_pid
>     where start.id != 23 && start.id != 7 && start.id != 61 && start.id != 230 &&
>           start.id != 232 && start.id != 270 && start.id != 271 && start.id != 202'
> 
> 
> (All the start.id filtering is hiding the syscalls that block for a long time)
> 
>  ># echo 'hist:keys=id.syscall,lat.buckets=10:sort=lat' > /sys/kernel/tracing/events/synthetic/syscall_wait/trigger  
> 
> <wait a while>
> 
>  ># cat /sys/kernel/tracing/events/synthetic/syscall_wait/hist  

And of course, I forgot to say what the above is doing :-p

I wanted to see how long syscalls block for. So I created a synthetic
event that connects with the starting of all system calls, with the
exit of the same system call, using the common_pid of the task as the
key to connect the two.

I record the id of the system call as well as the latency that is
recorded, and send that off to a synthetic event called "syscall_wait".

The '-e' option of the man page program sqlhist executes the command to
create the synthetic event.

Then I add a histogram to that event keying off the id (the ".syscall"
writes out the name of the system call along with the id), and the
latency "lat" grouping it in buckets of "5 microseconds", and sort it
by the latency.

I waited a while, and then reported the result.

When I first ran this, the system calls that block for a long time
filled up the histogram with useless data.  Those were the various
"poll" and "select" as well as (surprising) "futex" system call.

-- Steve

^ permalink raw reply	[flat|nested] 26+ messages in thread

* Re: [PATCH 01/17] libtracefs: Added new API tracefs_sql()
  2021-07-30 22:18 ` [PATCH 01/17] libtracefs: Added new API tracefs_sql() Steven Rostedt
@ 2021-08-01  6:32   ` Ahmed S. Darwish
  2021-08-01 22:10     ` Steven Rostedt
  2021-08-02 23:45   ` Namhyung Kim
  1 sibling, 1 reply; 26+ messages in thread
From: Ahmed S. Darwish @ 2021-08-01  6:32 UTC (permalink / raw)
  To: Steven Rostedt
  Cc: linux-trace-devel, linux-kernel, Tom Zanussi,
	Daniel Bristot de Oliveira, Masami Hiramatsu, Namhyung Kim,
	linux-rt-users, Clark Williams

On Fri, Jul 30, 2021, Steven Rostedt wrote:
>
> Currently it only supports simple SQL of the type:
>
>   SELECT start.common_pid AS pid, end.common_timestamp.usecs AS usecs
>     FROM sched_waking AS start on sched_switch AS end
                                 ^
                                 JOIN
>     ON start.pid = end.next_pid
>

^ permalink raw reply	[flat|nested] 26+ messages in thread

* Re: [PATCH 17/17] libtracefs: Add man page for tracefs_sql()
  2021-07-30 22:18 ` [PATCH 17/17] libtracefs: Add man page for tracefs_sql() Steven Rostedt
@ 2021-08-01 13:39   ` Ahmed S. Darwish
  2021-08-01 22:29     ` Steven Rostedt
  0 siblings, 1 reply; 26+ messages in thread
From: Ahmed S. Darwish @ 2021-08-01 13:39 UTC (permalink / raw)
  To: Steven Rostedt
  Cc: linux-trace-devel, linux-kernel, Tom Zanussi,
	Daniel Bristot de Oliveira, Masami Hiramatsu, Namhyung Kim,
	linux-rt-users, Clark Williams

On Fri, Jul 30, 2021, Steven Rostedt wrote:
> +
> +The SQL format is as follows:
> +
> +*SELECT* <fields> FROM <start-event> JOIN <end-event> ON <matching-fields> WHERE <filter>
> +
> +Note, although the examples show the SQL commands in uppercase, they are not required to
> +be so. That is, you can use "SELECT" or "select" or "sElEct".
> +

Maybe it would be helpful to mention that, unlike normal SELECT queries,
the JOIN and ON parts above are _not_ optional?

That is, generic "one event source" queries:

  SELECT common_pid,msr,val FROM write_msr WHERE msr=72

are not supported. (I wish they were though ;-))

BTW, thanks a lot for this work. It will finally make synthetic events
usable!

Kind regards,

--
Ahmed S. Darwish
Linutronix GmbH

^ permalink raw reply	[flat|nested] 26+ messages in thread

* Re: [PATCH 01/17] libtracefs: Added new API tracefs_sql()
  2021-08-01  6:32   ` Ahmed S. Darwish
@ 2021-08-01 22:10     ` Steven Rostedt
  0 siblings, 0 replies; 26+ messages in thread
From: Steven Rostedt @ 2021-08-01 22:10 UTC (permalink / raw)
  To: Ahmed S. Darwish
  Cc: linux-trace-devel, linux-kernel, Tom Zanussi,
	Daniel Bristot de Oliveira, Masami Hiramatsu, Namhyung Kim,
	linux-rt-users, Clark Williams

On Sun, 1 Aug 2021 08:32:15 +0200
"Ahmed S. Darwish" <a.darwish@linutronix.de> wrote:

> On Fri, Jul 30, 2021, Steven Rostedt wrote:
> >
> > Currently it only supports simple SQL of the type:
> >
> >   SELECT start.common_pid AS pid, end.common_timestamp.usecs AS usecs
> >     FROM sched_waking AS start on sched_switch AS end  
>                                  ^
>                                  JOIN
> >     ON start.pid = end.next_pid
> >  

Oops, thanks!

-- Steve



^ permalink raw reply	[flat|nested] 26+ messages in thread

* Re: [PATCH 17/17] libtracefs: Add man page for tracefs_sql()
  2021-08-01 13:39   ` Ahmed S. Darwish
@ 2021-08-01 22:29     ` Steven Rostedt
  2021-08-04 12:27       ` Ahmed S. Darwish
  0 siblings, 1 reply; 26+ messages in thread
From: Steven Rostedt @ 2021-08-01 22:29 UTC (permalink / raw)
  To: Ahmed S. Darwish
  Cc: linux-trace-devel, linux-kernel, Tom Zanussi,
	Daniel Bristot de Oliveira, Masami Hiramatsu, Namhyung Kim,
	linux-rt-users, Clark Williams

On Sun, 1 Aug 2021 15:39:25 +0200
"Ahmed S. Darwish" <a.darwish@linutronix.de> wrote:

> On Fri, Jul 30, 2021, Steven Rostedt wrote:
> > +
> > +The SQL format is as follows:
> > +
> > +*SELECT* <fields> FROM <start-event> JOIN <end-event> ON <matching-fields> WHERE <filter>
> > +
> > +Note, although the examples show the SQL commands in uppercase, they are not required to
> > +be so. That is, you can use "SELECT" or "select" or "sElEct".
> > +  
> 
> Maybe it would be helpful to mention that, unlike normal SELECT queries,
> the JOIN and ON parts above are _not_ optional?
> 
> That is, generic "one event source" queries:
> 
>   SELECT common_pid,msr,val FROM write_msr WHERE msr=72
> 
> are not supported. (I wish they were though ;-))

Actually, the sql parser should support it, but it will fail on the
creation of events. That's because I started trying to make this create
normal histograms. The problem is, that it can't really do a 1 to 1 on
histograms and selects, so I gave up. But perhaps for the subset it can
create, maybe I can still have it do so. That may require changing the
API slightly. 

I'm not a big SQL person, so I don't know all the magic and I have no
idea how to add the "values" part of the hist trigger.

I could use SQL CAST to let people redefine the types that histograms
allow, like:

   SELECT CAST(common_pid AS execname), CAST(id AS syscall) FROM sys_enter

and have that produce:

 echo 'hist:keys=common_pid.execname,id.syscall' > events/raw_syscalls/sys_enter/trigger

Any ideas for the syntax to get values? Or do people care about the
value parameter any more than just "hitcount"? I don't think I have
ever used it for anything.

> 
> BTW, thanks a lot for this work. It will finally make synthetic events
> usable!
> 

Thanks! It's also something to make it easier for me to use. And
hopefully, allow for even more complex synthetic events.

-- Steve

^ permalink raw reply	[flat|nested] 26+ messages in thread

* Re: [PATCH 01/17] libtracefs: Added new API tracefs_sql()
  2021-07-30 22:18 ` [PATCH 01/17] libtracefs: Added new API tracefs_sql() Steven Rostedt
  2021-08-01  6:32   ` Ahmed S. Darwish
@ 2021-08-02 23:45   ` Namhyung Kim
  2021-08-03  2:49     ` Steven Rostedt
  1 sibling, 1 reply; 26+ messages in thread
From: Namhyung Kim @ 2021-08-02 23:45 UTC (permalink / raw)
  To: Steven Rostedt
  Cc: Linux Trace Devel, linux-kernel, Tom Zanussi,
	Daniel Bristot de Oliveira, Masami Hiramatsu, linux-rt-users,
	Clark Williams

Hi Steve,

On Fri, Jul 30, 2021 at 3:18 PM Steven Rostedt <rostedt@goodmis.org> wrote:
>
> From: "Steven Rostedt (VMware)" <rostedt@goodmis.org>
>
> This adds the API tracefs_sql() that takes a tep_handle handler, a name,
> and a SQL string and parses it to produce a tracefs_synth synthetic event
> handler.
>
> Currently it only supports simple SQL of the type:
>
>   SELECT start.common_pid AS pid, end.common_timestamp.usecs AS usecs
>     FROM sched_waking AS start on sched_switch AS end
>     ON start.pid = end.next_pid
>
> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
> ---

[SNIP]
> diff --git a/src/sqlhist.l b/src/sqlhist.l
> new file mode 100644
> index 000000000000..3f394f37b738
> --- /dev/null
> +++ b/src/sqlhist.l
> @@ -0,0 +1,88 @@
> +%{
> +/* code here */
> +
> +#include <stdarg.h>
> +#include "sqlhist-parse.h"
> +
> +extern int my_yyinput(char *buf, int max);
> +
> +#undef YY_INPUT
> +#define YY_INPUT(b, r, m) ({r = my_yyinput(b, m);})
> +
> +#define YY_NO_INPUT
> +#define YY_NO_UNPUT
> +
> +#define YY_EXTRA_TYPE struct sqlhist_bison *
> +
> +#define HANDLE_COLUMN do { sb->line_idx += strlen(yytext); } while (0)
> +
> +%}
> +
> +%option caseless
> +
> +field          [a-z_][a-z0-9_\.]*
> +qstring                \"[^\"]*\"
> +hexnum         0x[0-9a-z]+
> +number         [0-9a-z]+

Do you mean a-f ?

Thanks,
Namhyung

^ permalink raw reply	[flat|nested] 26+ messages in thread

* Re: [PATCH 01/17] libtracefs: Added new API tracefs_sql()
  2021-08-02 23:45   ` Namhyung Kim
@ 2021-08-03  2:49     ` Steven Rostedt
  0 siblings, 0 replies; 26+ messages in thread
From: Steven Rostedt @ 2021-08-03  2:49 UTC (permalink / raw)
  To: Namhyung Kim
  Cc: Linux Trace Devel, linux-kernel, Tom Zanussi,
	Daniel Bristot de Oliveira, Masami Hiramatsu, linux-rt-users,
	Clark Williams

On Mon, 2 Aug 2021 16:45:39 -0700
Namhyung Kim <namhyung@kernel.org> wrote:

> > +%option caseless
> > +
> > +field          [a-z_][a-z0-9_\.]*
> > +qstring                \"[^\"]*\"
> > +hexnum         0x[0-9a-z]+
> > +number         [0-9a-z]+  
> 
> Do you mean a-f ?

Doh! Thanks, I'll fix that up for v2.

-- Steve

^ permalink raw reply	[flat|nested] 26+ messages in thread

* Re: [PATCH 17/17] libtracefs: Add man page for tracefs_sql()
  2021-08-01 22:29     ` Steven Rostedt
@ 2021-08-04 12:27       ` Ahmed S. Darwish
  0 siblings, 0 replies; 26+ messages in thread
From: Ahmed S. Darwish @ 2021-08-04 12:27 UTC (permalink / raw)
  To: Steven Rostedt
  Cc: linux-trace-devel, linux-kernel, Tom Zanussi,
	Daniel Bristot de Oliveira, Masami Hiramatsu, Namhyung Kim,
	linux-rt-users, Clark Williams

On Sun, Aug 01, 2021, Steven Rostedt wrote:
> On Sun, 1 Aug 2021 15:39:25 +0200
> "Ahmed S. Darwish" <a.darwish@linutronix.de> wrote:
>
> > On Fri, Jul 30, 2021, Steven Rostedt wrote:
> > > +
> > > +The SQL format is as follows:
> > > +
> > > +*SELECT* <fields> FROM <start-event> JOIN <end-event> ON <matching-fields> WHERE <filter>
> > > +
> > > +Note, although the examples show the SQL commands in uppercase, they are not required to
> > > +be so. That is, you can use "SELECT" or "select" or "sElEct".
> > > +
> >
> > Maybe it would be helpful to mention that, unlike normal SELECT queries,
> > the JOIN and ON parts above are _not_ optional?
> >
> > That is, generic "one event source" queries:
> >
> >   SELECT common_pid,msr,val FROM write_msr WHERE msr=72
> >
> > are not supported. (I wish they were though ;-))
>
> Actually, the sql parser should support it, but it will fail on the
> creation of events. That's because I started trying to make this create
> normal histograms. The problem is, that it can't really do a 1 to 1 on
> histograms and selects, so I gave up. But perhaps for the subset it can
> create, maybe I can still have it do so. That may require changing the
> API slightly.
>
> I'm not a big SQL person, so I don't know all the magic and I have no
> idea how to add the "values" part of the hist trigger.
>

Thanks! I've replied at the v2 thread.

(Discovered after-the-fact that a v3 was already sent, sorry..)

--
Ahmed S. Darwish
Linutronix GmbH

^ permalink raw reply	[flat|nested] 26+ messages in thread

end of thread, other threads:[~2021-08-04 12:27 UTC | newest]

Thread overview: 26+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2021-07-30 22:18 [PATCH 00/17] libtracefs: Introducing tracefs_sql() to create synthetice events with an SQL line Steven Rostedt
2021-07-30 22:18 ` [PATCH 01/17] libtracefs: Added new API tracefs_sql() Steven Rostedt
2021-08-01  6:32   ` Ahmed S. Darwish
2021-08-01 22:10     ` Steven Rostedt
2021-08-02 23:45   ` Namhyung Kim
2021-08-03  2:49     ` Steven Rostedt
2021-07-30 22:18 ` [PATCH 02/17] tracefs: Add unit tests for tracefs_sql() Steven Rostedt
2021-07-30 22:18 ` [PATCH 03/17] libtracefs: Add comparing start and end fields in tracefs_sql() Steven Rostedt
2021-07-30 22:18 ` [PATCH 04/17] libtracefs: Add unit test to test tracefs_sql() compare Steven Rostedt
2021-07-30 22:18 ` [PATCH 05/17] libtracefs: Add filtering for start and end events in tracefs_sql() Steven Rostedt
2021-07-30 22:18 ` [PATCH 06/17] libtracefs: Add unit test to test tracefs_sql() where clause Steven Rostedt
2021-07-30 22:18 ` [PATCH 07/17] libtracefs: Make sqlhist parser reentrant Steven Rostedt
2021-07-30 22:18 ` [PATCH 08/17] libtracefs: Make parser unique to libtracefs Steven Rostedt
2021-07-30 22:18 ` [PATCH 09/17] libtracefs: Add line number and index to expr structure Steven Rostedt
2021-07-30 22:18 ` [PATCH 10/17] libtracefs: Add a parse_error() helper function to record errors Steven Rostedt
2021-07-30 22:18 ` [PATCH 11/17] libtracefs: Add error message when match fields are not FROM and JOIN events Steven Rostedt
2021-07-30 22:18 ` [PATCH 12/17] libtracefs: Add error message when match or init fails from bad events Steven Rostedt
2021-07-30 22:18 ` [PATCH 13/17] libtracefs; Add error message for bad selections to SQL sequence Steven Rostedt
2021-07-30 22:18 ` [PATCH 14/17] libtracefs: Add error message when compare fields fail Steven Rostedt
2021-07-30 22:18 ` [PATCH 15/17] libtracefs: Add error message for grouping events in SQL filter Steven Rostedt
2021-07-30 22:18 ` [PATCH 16/17] libtracefs: Add error message for bad filters in SQL statement Steven Rostedt
2021-07-30 22:18 ` [PATCH 17/17] libtracefs: Add man page for tracefs_sql() Steven Rostedt
2021-08-01 13:39   ` Ahmed S. Darwish
2021-08-01 22:29     ` Steven Rostedt
2021-08-04 12:27       ` Ahmed S. Darwish
2021-07-30 22:31 ` [PATCH 00/17] libtracefs: Introducing tracefs_sql() to create synthetice events with an SQL line Steven Rostedt

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