From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752866AbYJaEDe (ORCPT ); Fri, 31 Oct 2008 00:03:34 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1750783AbYJaEDZ (ORCPT ); Fri, 31 Oct 2008 00:03:25 -0400 Received: from hrndva-omtalb.mail.rr.com ([71.74.56.124]:36971 "EHLO hrndva-omtalb.mail.rr.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750715AbYJaEDY (ORCPT ); Fri, 31 Oct 2008 00:03:24 -0400 Date: Fri, 31 Oct 2008 00:03:22 -0400 (EDT) From: Steven Rostedt X-X-Sender: rostedt@gandalf.stny.rr.com To: Andrew Morton cc: linux-kernel@vger.kernel.org, mingo@elte.hu, tglx@linutronix.de, peterz@infradead.org, torvalds@linux-foundation.org, srostedt@redhat.com Subject: [PATCH] ftrace: nmi safe code clean ups In-Reply-To: <20081030141048.904c82e1.akpm@linux-foundation.org> Message-ID: References: <20081030200831.467420488@goodmis.org> <20081030201127.820600693@goodmis.org> <20081030133228.824e3f69.akpm@linux-foundation.org> <20081030141048.904c82e1.akpm@linux-foundation.org> User-Agent: Alpine 1.10 (DEB 962 2008-03-14) MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org This patch cleans up the NMI safe code for dynamic ftrace as suggested by Andrew Morton. Signed-off-by: Steven Rostedt --- arch/arm/include/asm/ftrace.h | 4 ++-- arch/powerpc/include/asm/ftrace.h | 4 ++-- arch/sh/include/asm/ftrace.h | 4 ++-- arch/sparc/include/asm/ftrace.h | 4 ++-- arch/x86/include/asm/ftrace.h | 10 +++++----- arch/x86/kernel/ftrace.c | 16 ++++++++-------- include/linux/ftrace.h | 3 +++ kernel/trace/trace.c | 9 ++++----- 8 files changed, 28 insertions(+), 26 deletions(-) Index: linux-tip.git/arch/arm/include/asm/ftrace.h =================================================================== --- linux-tip.git.orig/arch/arm/include/asm/ftrace.h 2008-10-30 10:27:09.000000000 -0400 +++ linux-tip.git/arch/arm/include/asm/ftrace.h 2008-10-30 23:24:18.000000000 -0400 @@ -2,8 +2,8 @@ #define _ASM_ARM_FTRACE #ifndef __ASSEMBLY__ -#define ftrace_nmi_enter() do { } while (0) -#define ftrace_nmi_exit() do { } while (0) +static inline void ftrace_nmi_enter(void) { } +static inline void ftrace_nmi_exit(void) { } #endif #ifdef CONFIG_FUNCTION_TRACER Index: linux-tip.git/arch/powerpc/include/asm/ftrace.h =================================================================== --- linux-tip.git.orig/arch/powerpc/include/asm/ftrace.h 2008-10-30 10:27:09.000000000 -0400 +++ linux-tip.git/arch/powerpc/include/asm/ftrace.h 2008-10-30 23:24:30.000000000 -0400 @@ -2,8 +2,8 @@ #define _ASM_POWERPC_FTRACE #ifndef __ASSEMBLY__ -#define ftrace_nmi_enter() do { } while (0) -#define ftrace_nmi_exit() do { } while (0) +static inline void ftrace_nmi_enter(void) { } +static inline void ftrace_nmi_exit(void) { } #endif #ifdef CONFIG_FUNCTION_TRACER Index: linux-tip.git/arch/sh/include/asm/ftrace.h =================================================================== --- linux-tip.git.orig/arch/sh/include/asm/ftrace.h 2008-10-30 10:27:09.000000000 -0400 +++ linux-tip.git/arch/sh/include/asm/ftrace.h 2008-10-30 23:24:43.000000000 -0400 @@ -2,8 +2,8 @@ #define __ASM_SH_FTRACE_H #ifndef __ASSEMBLY__ -#define ftrace_nmi_enter() do { } while (0) -#define ftrace_nmi_exit() do { } while (0) +static inline void ftrace_nmi_enter(void) { } +static inline void ftrace_nmi_exit(void) { } #endif #ifndef __ASSEMBLY__ Index: linux-tip.git/arch/sparc/include/asm/ftrace.h =================================================================== --- linux-tip.git.orig/arch/sparc/include/asm/ftrace.h 2008-10-30 10:27:09.000000000 -0400 +++ linux-tip.git/arch/sparc/include/asm/ftrace.h 2008-10-30 23:24:50.000000000 -0400 @@ -2,8 +2,8 @@ #define _ASM_SPARC64_FTRACE #ifndef __ASSEMBLY__ -#define ftrace_nmi_enter() do { } while (0) -#define ftrace_nmi_exit() do { } while (0) +static inline void ftrace_nmi_enter(void) { } +static inline void ftrace_nmi_exit(void) { } #endif #ifdef CONFIG_MCOUNT Index: linux-tip.git/arch/x86/include/asm/ftrace.h =================================================================== --- linux-tip.git.orig/arch/x86/include/asm/ftrace.h 2008-10-30 13:16:22.000000000 -0400 +++ linux-tip.git/arch/x86/include/asm/ftrace.h 2008-10-30 23:25:26.000000000 -0400 @@ -22,16 +22,16 @@ static inline unsigned long ftrace_call_ extern void ftrace_nmi_enter(void); extern void ftrace_nmi_exit(void); #else -#define ftrace_nmi_enter() do { } while (0) -#define ftrace_nmi_exit() do { } while (0) -#endif +static inline void ftrace_nmi_enter(void) { } +static inline void ftrace_nmi_exit(void) { } #endif +#endif /* __ASSEMBLY__ */ #else /* CONFIG_FUNCTION_TRACER */ #ifndef __ASSEMBLY__ -#define ftrace_nmi_enter() do { } while (0) -#define ftrace_nmi_exit() do { } while (0) +static inline void ftrace_nmi_enter(void) { } +static inline void ftrace_nmi_exit(void) { } #endif #endif /* CONFIG_FUNCTION_TRACER */ Index: linux-tip.git/arch/x86/kernel/ftrace.c =================================================================== --- linux-tip.git.orig/arch/x86/kernel/ftrace.c 2008-10-30 16:07:05.000000000 -0400 +++ linux-tip.git/arch/x86/kernel/ftrace.c 2008-10-30 23:30:19.000000000 -0400 @@ -67,7 +67,7 @@ unsigned char *ftrace_call_replace(unsig * * Two buffers are added: An IP buffer and a "code" buffer. * - * 1) Put in the instruction pointer into the IP buffer + * 1) Put the instruction pointer into the IP buffer * and the new code into the "code" buffer. * 2) Set a flag that says we are modifying code * 3) Wait for any running NMIs to finish. @@ -85,14 +85,14 @@ unsigned char *ftrace_call_replace(unsig * are the same as what exists. */ -static atomic_t in_nmi; -static int mod_code_status; -static int mod_code_write; -static void *mod_code_ip; -static void *mod_code_newcode; +static atomic_t in_nmi = ATOMIC_INIT(0); +static int mod_code_status; /* holds return value of text write */ +static int mod_code_write; /* set when NMI should do the write */ +static void *mod_code_ip; /* holds the IP to write to */ +static void *mod_code_newcode; /* holds the text to write to the IP */ -static int nmi_wait_count; -static atomic_t nmi_update_count; +static unsigned nmi_wait_count; +static atomic_t nmi_update_count = ATOMIC_INIT(0); int ftrace_arch_read_dyn_info(char *buf, int size) { Index: linux-tip.git/include/linux/ftrace.h =================================================================== --- linux-tip.git.orig/include/linux/ftrace.h 2008-10-30 10:27:07.000000000 -0400 +++ linux-tip.git/include/linux/ftrace.h 2008-10-30 23:31:33.000000000 -0400 @@ -74,6 +74,9 @@ extern void ftrace_caller(void); extern void ftrace_call(void); extern void mcount_call(void); +/* May be defined in arch */ +extern int ftrace_arch_read_dyn_info(char *buf, int size); + /** * ftrace_modify_code - modify code segment * @ip: the address of the code segment Index: linux-tip.git/kernel/trace/trace.c =================================================================== --- linux-tip.git.orig/kernel/trace/trace.c 2008-10-30 16:07:05.000000000 -0400 +++ linux-tip.git/kernel/trace/trace.c 2008-10-30 23:33:41.000000000 -0400 @@ -2837,10 +2837,6 @@ static struct file_operations tracing_ma #ifdef CONFIG_DYNAMIC_FTRACE -#define DYN_INFO_BUF_SIZE 1023 -static char ftrace_dyn_info_buffer[DYN_INFO_BUF_SIZE+1]; -static DEFINE_MUTEX(dyn_info_mutex); - int __weak ftrace_arch_read_dyn_info(char *buf, int size) { return 0; @@ -2850,14 +2846,17 @@ static ssize_t tracing_read_dyn_info(struct file *filp, char __user *ubuf, size_t cnt, loff_t *ppos) { + static char ftrace_dyn_info_buffer[1024]; + static DEFINE_MUTEX(dyn_info_mutex); unsigned long *p = filp->private_data; char *buf = ftrace_dyn_info_buffer; + int size = ARRAY_SIZE(ftrace_dyn_info_buffer); int r; mutex_lock(&dyn_info_mutex); r = sprintf(buf, "%ld ", *p); - r += ftrace_arch_read_dyn_info(buf+r, DYN_INFO_BUF_SIZE-r); + r += ftrace_arch_read_dyn_info(buf+r, (size-1)-r); buf[r++] = '\n'; r = simple_read_from_buffer(ubuf, cnt, ppos, buf, r);