LKML Archive on lore.kernel.org
help / color / mirror / Atom feed
From: Alexander Shishkin <virtuoso@slind.org>
To: "Arve Hjønnevåg" <arve@android.com>
Cc: linux-arm-kernel@lists.infradead.org, linux-omap@vger.kernel.org,
	Russell King <linux@arm.linux.org.uk>,
	Jason Wessel <jason.wessel@windriver.com>,
	Greg Kroah-Hartman <gregkh@suse.de>,
	linux-kernel@vger.kernel.org
Subject: Re: [PATCH 4/8] ARM: etm: Allow range selection
Date: Tue, 15 Feb 2011 15:50:54 +0200	[thread overview]
Message-ID: <20110215135054.GD18248@shisha.kicks-ass.net> (raw)
In-Reply-To: <1297750276-12475-4-git-send-email-arve@android.com>

On Mon, Feb 14, 2011 at 10:11:12PM -0800, Arve Hjønnevåg wrote:
> Trace kernel text segment by default as before, allow tracing of other
> ranges by writing a range to /sys/devices/etm/trace_range, or to trace
> everything by writing 0 0.

Since you're adding this, I think it might make sense to add a 3rd optional
ctx id field, so that userspace tracing is also possible, especially when
on-chip ETB sizes increase to something more sensible than what they are
these days.

Thanks!

> 
> Signed-off-by: Arve Hjønnevåg <arve@android.com>
> ---
>  arch/arm/kernel/etm.c |   49 ++++++++++++++++++++++++++++++++++++++++++++++---
>  1 files changed, 46 insertions(+), 3 deletions(-)
> 
> diff --git a/arch/arm/kernel/etm.c b/arch/arm/kernel/etm.c
> index bc7d8f2..8a1c422 100644
> --- a/arch/arm/kernel/etm.c
> +++ b/arch/arm/kernel/etm.c
> @@ -40,12 +40,17 @@ struct tracectx {
>  	unsigned long	flags;
>  	int		ncmppairs;
>  	int		etm_portsz;
> +	unsigned long	range_start;
> +	unsigned long	range_end;
>  	struct device	*dev;
>  	struct clk	*emu_clk;
>  	struct mutex	mutex;
>  };
>  
> -static struct tracectx tracer;
> +static struct tracectx tracer = {
> +	.range_start = (unsigned long)_stext,
> +	.range_end = (unsigned long)_etext,
> +};
>  
>  static inline bool trace_isrunning(struct tracectx *t)
>  {
> @@ -115,8 +120,12 @@ static int trace_start(struct tracectx *t)
>  		return -EFAULT;
>  	}
>  
> -	etm_setup_address_range(t, 1, (unsigned long)_stext,
> -			(unsigned long)_etext, 0, 0);
> +	if (t->range_start || t->range_end)
> +		etm_setup_address_range(t, 1,
> +					t->range_start, t->range_end, 0, 0);
> +	else
> +		etm_writel(t, ETMTE_INCLEXCL, ETMR_TRACEENCTRL);
> +
>  	etm_writel(t, 0, ETMR_TRACEENCTRL2);
>  	etm_writel(t, 0, ETMR_TRACESSCTRL);
>  	etm_writel(t, 0x6f, ETMR_TRACEENEVT);
> @@ -525,6 +534,35 @@ static ssize_t trace_mode_store(struct kobject *kobj,
>  static struct kobj_attribute trace_mode_attr =
>  	__ATTR(trace_mode, 0644, trace_mode_show, trace_mode_store);
>  
> +static ssize_t trace_range_show(struct kobject *kobj,
> +				  struct kobj_attribute *attr,
> +				  char *buf)
> +{
> +	return sprintf(buf, "%08lx %08lx\n",
> +			tracer.range_start, tracer.range_end);
> +}
> +
> +static ssize_t trace_range_store(struct kobject *kobj,
> +				   struct kobj_attribute *attr,
> +				   const char *buf, size_t n)
> +{
> +	unsigned long range_start, range_end;
> +
> +	if (sscanf(buf, "%lx %lx", &range_start, &range_end) != 2)
> +		return -EINVAL;
> +
> +	mutex_lock(&tracer.mutex);
> +	tracer.range_start = range_start;
> +	tracer.range_end = range_end;
> +	mutex_unlock(&tracer.mutex);
> +
> +	return n;
> +}
> +
> +
> +static struct kobj_attribute trace_range_attr =
> +	__ATTR(trace_range, 0644, trace_range_show, trace_range_store);
> +
>  static int __init etm_probe(struct amba_device *dev, struct amba_id *id)
>  {
>  	struct tracectx *t = &tracer;
> @@ -576,6 +614,10 @@ static int __init etm_probe(struct amba_device *dev, struct amba_id *id)
>  	if (ret)
>  		dev_dbg(&dev->dev, "Failed to create trace_mode in sysfs\n");
>  
> +	ret = sysfs_create_file(&dev->dev.kobj, &trace_range_attr.attr);
> +	if (ret)
> +		dev_dbg(&dev->dev, "Failed to create trace_range in sysfs\n");
> +
>  	dev_dbg(t->dev, "ETM AMBA driver initialized.\n");
>  
>  out:
> @@ -605,6 +647,7 @@ static int etm_remove(struct amba_device *dev)
>  	sysfs_remove_file(&dev->dev.kobj, &trace_running_attr.attr);
>  	sysfs_remove_file(&dev->dev.kobj, &trace_info_attr.attr);
>  	sysfs_remove_file(&dev->dev.kobj, &trace_mode_attr.attr);
> +	sysfs_remove_file(&dev->dev.kobj, &trace_range_attr.attr);
>  
>  	return 0;
>  }
> -- 
> 1.7.3.1
> 

  reply	other threads:[~2011-02-15 13:58 UTC|newest]

Thread overview: 19+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2011-02-03  2:54 [PATCH 1/5] ARM: etm: Don't require clock control Arve Hjønnevåg
2011-02-03  2:54 ` [PATCH 2/5] ARM: etm: Don't limit tracing to only non-secure code Arve Hjønnevåg
2011-02-03  2:54 ` [PATCH 3/5] ARM: etm: Don't trigger another overflow when trying to clear the RAM-full status Arve Hjønnevåg
2011-02-03  2:54 ` [PATCH 4/5] ARM: etm: Allow range selection Arve Hjønnevåg
2011-02-03  2:54 ` [PATCH 5/5] ARM: etm: Configure data tracing Arve Hjønnevåg
2011-02-03 12:45 ` [PATCH 1/5] ARM: etm: Don't require clock control Mark Brown
2011-02-04  0:30   ` Arve Hjønnevåg
2011-02-04 14:31     ` Mark Brown
2011-02-15  6:11 ` [PATCH 1/8] " Arve Hjønnevåg
2011-02-15  6:11 ` [PATCH 2/8] ARM: etm: Don't limit tracing to only non-secure code Arve Hjønnevåg
2011-02-15  6:11 ` [PATCH 3/8] ARM: etm: Don't try to clear the buffer full status after reading the buffer Arve Hjønnevåg
2011-02-15  6:11 ` [PATCH 4/8] ARM: etm: Allow range selection Arve Hjønnevåg
2011-02-15 13:50   ` Alexander Shishkin [this message]
2011-02-15 23:04     ` Arve Hjønnevåg
2011-02-15  6:11 ` [PATCH 5/8] ARM: etm: Configure data tracing Arve Hjønnevåg
2011-02-15  6:11 ` [PATCH 6/8] ARM: etm: Add some missing locks and error checks Arve Hjønnevåg
2011-02-15  6:11 ` [PATCH 7/8] ARM: etm: Return the entire trace buffer if it is empty after reset Arve Hjønnevåg
2011-02-15  6:11 ` [PATCH 8/8] ARM: etm: Support multiple ETMs/PTMs Arve Hjønnevåg
2011-02-24  1:36 ` [PATCH 9/9 (originally 8)] ARM: etm: Power down etm(s) when tracing is not enabled Arve Hjønnevåg

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20110215135054.GD18248@shisha.kicks-ass.net \
    --to=virtuoso@slind.org \
    --cc=arve@android.com \
    --cc=gregkh@suse.de \
    --cc=jason.wessel@windriver.com \
    --cc=linux-arm-kernel@lists.infradead.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-omap@vger.kernel.org \
    --cc=linux@arm.linux.org.uk \
    --subject='Re: [PATCH 4/8] ARM: etm: Allow range selection' \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).