diff mbox

drm: drm_err: Remove unnecessary __func__ argument

Message ID 1413090537.22149.16.camel@joe-AO725 (mailing list archive)
State New, archived
Headers show

Commit Message

Joe Perches Oct. 12, 2014, 5:08 a.m. UTC 
Removing the unnecessary drm_err __func__ argument by using
the equivalent %pf and __builtin_return_address(0) makes the
code smaller for every use of the DRM_ERROR macro.

For instance: (allmodconfig)

$ size drivers/gpu/drm/i915/i915.o*
   text	   data	    bss	    dec	    hex	filename
 922447	 193257	 296736	1412440	 158d58	drivers/gpu/drm/i915/i915.o.new
 928111	 193257	 296736	1418104	 15a378	drivers/gpu/drm/i915/i915.o.old

Signed-off-by: Joe Perches <joe@perches.com>
---
 drivers/gpu/drm/drm_drv.c | 5 +++--
 include/drm/drmP.h        | 8 ++++----
 2 files changed, 7 insertions(+), 6 deletions(-)

Comments

David Herrmann Oct. 13, 2014, 3:46 p.m. UTC | #1 
Hi

On Sun, Oct 12, 2014 at 7:08 AM, Joe Perches <joe@perches.com> wrote:
> Removing the unnecessary drm_err __func__ argument by using
> the equivalent %pf and __builtin_return_address(0) makes the
> code smaller for every use of the DRM_ERROR macro.
>
> For instance: (allmodconfig)
>
> $ size drivers/gpu/drm/i915/i915.o*
>    text    data     bss     dec     hex filename
>  922447  193257  296736 1412440  158d58 drivers/gpu/drm/i915/i915.o.new
>  928111  193257  296736 1418104  15a378 drivers/gpu/drm/i915/i915.o.old

You might want to mention that this requires a binary-search through
kallsyms on each call. I guess that's the reason you didn't use it for
drm_ut_debug_printk()? I'm fine with doing this on drm_err(). Looks
good.

Thanks
David

> Signed-off-by: Joe Perches <joe@perches.com>
> ---
>  drivers/gpu/drm/drm_drv.c | 5 +++--
>  include/drm/drmP.h        | 8 ++++----
>  2 files changed, 7 insertions(+), 6 deletions(-)
>
> diff --git a/drivers/gpu/drm/drm_drv.c b/drivers/gpu/drm/drm_drv.c
> index 9f0e1b9..e9263d9 100644
> --- a/drivers/gpu/drm/drm_drv.c
> +++ b/drivers/gpu/drm/drm_drv.c
> @@ -68,7 +68,7 @@ static struct idr drm_minors_idr;
>  struct class *drm_class;
>  static struct dentry *drm_debugfs_root;
>
> -void drm_err(const char *func, const char *format, ...)
> +void drm_err(const char *format, ...)
>  {
>         struct va_format vaf;
>         va_list args;
> @@ -78,7 +78,8 @@ void drm_err(const char *func, const char *format, ...)
>         vaf.fmt = format;
>         vaf.va = &args;
>
> -       printk(KERN_ERR "[" DRM_NAME ":%s] *ERROR* %pV", func, &vaf);
> +       printk(KERN_ERR "[" DRM_NAME ":%pf] *ERROR* %pV",
> +              __builtin_return_address(0), &vaf);
>
>         va_end(args);
>  }
> diff --git a/include/drm/drmP.h b/include/drm/drmP.h
> index ca374ac..5e9ff52 100644
> --- a/include/drm/drmP.h
> +++ b/include/drm/drmP.h
> @@ -125,8 +125,8 @@ struct reservation_object;
>  extern __printf(2, 3)
>  void drm_ut_debug_printk(const char *function_name,
>                          const char *format, ...);
> -extern __printf(2, 3)
> -void drm_err(const char *func, const char *format, ...);
> +extern __printf(1, 2)
> +void drm_err(const char *format, ...);
>
>  /***********************************************************************/
>  /** \name DRM template customization defaults */
> @@ -168,7 +168,7 @@ void drm_err(const char *func, const char *format, ...);
>   * \param arg arguments
>   */
>  #define DRM_ERROR(fmt, ...)                            \
> -       drm_err(__func__, fmt, ##__VA_ARGS__)
> +       drm_err(fmt, ##__VA_ARGS__)
>
>  /**
>   * Rate limited error output.  Like DRM_ERROR() but won't flood the log.
> @@ -183,7 +183,7 @@ void drm_err(const char *func, const char *format, ...);
>                                       DEFAULT_RATELIMIT_BURST);         \
>                                                                         \
>         if (__ratelimit(&_rs))                                          \
> -               drm_err(__func__, fmt, ##__VA_ARGS__);                  \
> +               drm_err(fmt, ##__VA_ARGS__);                            \
>  })
>
>  #define DRM_INFO(fmt, ...)                             \
>
>
> _______________________________________________
> dri-devel mailing list
> dri-devel@lists.freedesktop.org
> http://lists.freedesktop.org/mailman/listinfo/dri-devel
Joe Perches Oct. 13, 2014, 3:54 p.m. UTC | #2 
On Mon, 2014-10-13 at 17:46 +0200, David Herrmann wrote:
> Hi
> 
> On Sun, Oct 12, 2014 at 7:08 AM, Joe Perches <joe@perches.com> wrote:
> > Removing the unnecessary drm_err __func__ argument by using
> > the equivalent %pf and __builtin_return_address(0) makes the
> > code smaller for every use of the DRM_ERROR macro.
> >
> > For instance: (allmodconfig)
> >
> > $ size drivers/gpu/drm/i915/i915.o*
> >    text    data     bss     dec     hex filename
> >  922447  193257  296736 1412440  158d58 drivers/gpu/drm/i915/i915.o.new
> >  928111  193257  296736 1418104  15a378 drivers/gpu/drm/i915/i915.o.old
> 
> You might want to mention that this requires a binary-search through
> kallsyms on each call.

All these calls are infrequently taken error paths
and the cost of the printk itself is _far_ higher
than a binary search for the symbol.

> I guess that's the reason you didn't use it for
> drm_ut_debug_printk()? I'm fine with doing this on drm_err(). Looks
> good.

No, the reason I didn't do it there is that those calls
should really be consolidated and be able to use dynamic_debug.
It'd be a separate patch.

cheers, Joe
diff mbox

Patch

diff --git a/drivers/gpu/drm/drm_drv.c b/drivers/gpu/drm/drm_drv.c
index 9f0e1b9..e9263d9 100644
--- a/drivers/gpu/drm/drm_drv.c
+++ b/drivers/gpu/drm/drm_drv.c
@@ -68,7 +68,7 @@  static struct idr drm_minors_idr;
 struct class *drm_class;
 static struct dentry *drm_debugfs_root;
 
-void drm_err(const char *func, const char *format, ...)
+void drm_err(const char *format, ...)
 {
 	struct va_format vaf;
 	va_list args;
@@ -78,7 +78,8 @@  void drm_err(const char *func, const char *format, ...)
 	vaf.fmt = format;
 	vaf.va = &args;
 
-	printk(KERN_ERR "[" DRM_NAME ":%s] *ERROR* %pV", func, &vaf);
+	printk(KERN_ERR "[" DRM_NAME ":%pf] *ERROR* %pV",
+	       __builtin_return_address(0), &vaf);
 
 	va_end(args);
 }
diff --git a/include/drm/drmP.h b/include/drm/drmP.h
index ca374ac..5e9ff52 100644
--- a/include/drm/drmP.h
+++ b/include/drm/drmP.h
@@ -125,8 +125,8 @@  struct reservation_object;
 extern __printf(2, 3)
 void drm_ut_debug_printk(const char *function_name,
 			 const char *format, ...);
-extern __printf(2, 3)
-void drm_err(const char *func, const char *format, ...);
+extern __printf(1, 2)
+void drm_err(const char *format, ...);
 
 /***********************************************************************/
 /** \name DRM template customization defaults */
@@ -168,7 +168,7 @@  void drm_err(const char *func, const char *format, ...);
  * \param arg arguments
  */
 #define DRM_ERROR(fmt, ...)				\
-	drm_err(__func__, fmt, ##__VA_ARGS__)
+	drm_err(fmt, ##__VA_ARGS__)
 
 /**
  * Rate limited error output.  Like DRM_ERROR() but won't flood the log.
@@ -183,7 +183,7 @@  void drm_err(const char *func, const char *format, ...);
 				      DEFAULT_RATELIMIT_BURST);		\
 									\
 	if (__ratelimit(&_rs))						\
-		drm_err(__func__, fmt, ##__VA_ARGS__);			\
+		drm_err(fmt, ##__VA_ARGS__);				\
 })
 
 #define DRM_INFO(fmt, ...)				\