[v2 PATCH] ftrace: Speed up recordmcount

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* [v2 PATCH] ftrace: Speed up recordmcount
@ 2010-10-27 16:24 Wu Zhangjin
  2010-10-28  2:21 ` Steven Rostedt
                   ` (2 more replies)
  0 siblings, 3 replies; 6+ messages in thread
From: Wu Zhangjin @ 2010-10-27 16:24 UTC (permalink / raw)
  To: rostedt, linux-kernel
  Cc: mingo, John Reiser, Sam Ravnborg, linux-kbuild, Michal Marek,
	Wu Zhangjin

From: Wu Zhangjin <wuzhangjin@gmail.com>

cmd_record_mcount is used to locate the _mcount symbols in the object
files, only the files compiled with -pg has the _mcount symbol, so, it
is only needed for such files, but the current cmd_record_mcount is used
for all of the object files, so, we need to fix it and speed it up.

Since -pg may be removed by the method used in kernel/trace/Makefile:

ORIG_CFLAGS := $(KBUILD_CFLAGS)
KBUILD_CFLAGS = $(subst -pg,,$(ORIG_CFLAGS))

Or may be removed by the method used in arch/x86/kernel/Makefile:

CONFIG_REMOVE_file.o = -pg

So, we must check the last variable stores the compiling flags, that is
c_flags(Please refer to cmd_cc_o_c and rule_cc_o_c defined in
scripts/Makefile.build) and since the CFLAGS_REMOVE_file.o is already
filtered in _c_flags(Please refer to scripts/Makefile.lib) and _c_flags
has less symbols, therefore, we only need to check _c_flags.

---------------
Changes from v1:

  o Don't touch Makefile for CONFIG_FTRACE_MCOUNT_RECORD is enough
  o Use _c_flags intead of KBUILD_CFLAGS to cover CONFIG_REMOVE_file.o = -pg
  (feedback from Steven Rostedt <rostedt@goodmis.org>)

Signed-off-by: Wu Zhangjin <wuzhangjin@gmail.com>
---
 scripts/Makefile.build |   13 +++++++++----
 1 files changed, 9 insertions(+), 4 deletions(-)

diff --git a/scripts/Makefile.build b/scripts/Makefile.build
index 5ad25e1..0ad6108 100644
--- a/scripts/Makefile.build
+++ b/scripts/Makefile.build
@@ -214,17 +214,22 @@ ifdef BUILD_C_RECORDMCOUNT
 # The empty.o file is created in the make process in order to determine
 #  the target endianness and word size. It is made before all other C
 #  files, including recordmcount.
-cmd_record_mcount = if [ $(@) != "scripts/mod/empty.o" ]; then			\
-			$(objtree)/scripts/recordmcount "$(@)";			\
-		    fi;
+sub_cmd_record_mcount =					\
+	if [ $(@) != "scripts/mod/empty.o" ]; then	\
+		$(objtree)/scripts/recordmcount "$(@)";	\
+	fi;
 else
-cmd_record_mcount = set -e ; perl $(srctree)/scripts/recordmcount.pl "$(ARCH)" \
+sub_cmd_record_mcount = set -e ; perl $(srctree)/scripts/recordmcount.pl "$(ARCH)" \
 	"$(if $(CONFIG_CPU_BIG_ENDIAN),big,little)" \
 	"$(if $(CONFIG_64BIT),64,32)" \
 	"$(OBJDUMP)" "$(OBJCOPY)" "$(CC) $(KBUILD_CFLAGS)" \
 	"$(LD)" "$(NM)" "$(RM)" "$(MV)" \
 	"$(if $(part-of-module),1,0)" "$(@)";
 endif
+cmd_record_mcount = 						\
+	if [ "$(findstring -pg,$(_c_flags))" == "-pg" ]; then	\
+		$(sub_cmd_record_mcount)			\
+	fi;
 endif
 
 define rule_cc_o_c
-- 
1.7.1


^ permalink raw reply related	[flat|nested] 6+ messages in thread

* Re: [v2 PATCH] ftrace: Speed up recordmcount
  2010-10-27 16:24 [v2 PATCH] ftrace: Speed up recordmcount Wu Zhangjin
@ 2010-10-28  2:21 ` Steven Rostedt
  2010-10-28 21:05 ` Michal Marek
  2010-12-22 13:15 ` [tip:perf/core] " tip-bot for Wu Zhangjin
  2 siblings, 0 replies; 6+ messages in thread
From: Steven Rostedt @ 2010-10-28  2:21 UTC (permalink / raw)
  To: Wu Zhangjin
  Cc: linux-kernel, mingo, John Reiser, Sam Ravnborg, linux-kbuild,
	Michal Marek

Michal,

Can you give an Acked-by: on this patch?

Thanks!

-- Steve


On Thu, 2010-10-28 at 00:24 +0800, Wu Zhangjin wrote:
> From: Wu Zhangjin <wuzhangjin@gmail.com>
> 
> cmd_record_mcount is used to locate the _mcount symbols in the object
> files, only the files compiled with -pg has the _mcount symbol, so, it
> is only needed for such files, but the current cmd_record_mcount is used
> for all of the object files, so, we need to fix it and speed it up.
> 
> Since -pg may be removed by the method used in kernel/trace/Makefile:
> 
> ORIG_CFLAGS := $(KBUILD_CFLAGS)
> KBUILD_CFLAGS = $(subst -pg,,$(ORIG_CFLAGS))
> 
> Or may be removed by the method used in arch/x86/kernel/Makefile:
> 
> CONFIG_REMOVE_file.o = -pg
> 
> So, we must check the last variable stores the compiling flags, that is
> c_flags(Please refer to cmd_cc_o_c and rule_cc_o_c defined in
> scripts/Makefile.build) and since the CFLAGS_REMOVE_file.o is already
> filtered in _c_flags(Please refer to scripts/Makefile.lib) and _c_flags
> has less symbols, therefore, we only need to check _c_flags.
> 
> ---------------
> Changes from v1:
> 
>   o Don't touch Makefile for CONFIG_FTRACE_MCOUNT_RECORD is enough
>   o Use _c_flags intead of KBUILD_CFLAGS to cover CONFIG_REMOVE_file.o = -pg
>   (feedback from Steven Rostedt <rostedt@goodmis.org>)
> 
> Signed-off-by: Wu Zhangjin <wuzhangjin@gmail.com>
> ---
>  scripts/Makefile.build |   13 +++++++++----
>  1 files changed, 9 insertions(+), 4 deletions(-)
> 
> diff --git a/scripts/Makefile.build b/scripts/Makefile.build
> index 5ad25e1..0ad6108 100644
> --- a/scripts/Makefile.build
> +++ b/scripts/Makefile.build
> @@ -214,17 +214,22 @@ ifdef BUILD_C_RECORDMCOUNT
>  # The empty.o file is created in the make process in order to determine
>  #  the target endianness and word size. It is made before all other C
>  #  files, including recordmcount.
> -cmd_record_mcount = if [ $(@) != "scripts/mod/empty.o" ]; then			\
> -			$(objtree)/scripts/recordmcount "$(@)";			\
> -		    fi;
> +sub_cmd_record_mcount =					\
> +	if [ $(@) != "scripts/mod/empty.o" ]; then	\
> +		$(objtree)/scripts/recordmcount "$(@)";	\
> +	fi;
>  else
> -cmd_record_mcount = set -e ; perl $(srctree)/scripts/recordmcount.pl "$(ARCH)" \
> +sub_cmd_record_mcount = set -e ; perl $(srctree)/scripts/recordmcount.pl "$(ARCH)" \
>  	"$(if $(CONFIG_CPU_BIG_ENDIAN),big,little)" \
>  	"$(if $(CONFIG_64BIT),64,32)" \
>  	"$(OBJDUMP)" "$(OBJCOPY)" "$(CC) $(KBUILD_CFLAGS)" \
>  	"$(LD)" "$(NM)" "$(RM)" "$(MV)" \
>  	"$(if $(part-of-module),1,0)" "$(@)";
>  endif
> +cmd_record_mcount = 						\
> +	if [ "$(findstring -pg,$(_c_flags))" == "-pg" ]; then	\
> +		$(sub_cmd_record_mcount)			\
> +	fi;
>  endif
>  
>  define rule_cc_o_c



^ permalink raw reply	[flat|nested] 6+ messages in thread

* Re: [v2 PATCH] ftrace: Speed up recordmcount
  2010-10-27 16:24 [v2 PATCH] ftrace: Speed up recordmcount Wu Zhangjin
  2010-10-28  2:21 ` Steven Rostedt
@ 2010-10-28 21:05 ` Michal Marek
  2010-11-09  5:35   ` wu zhangjin
  2010-12-22 13:15 ` [tip:perf/core] " tip-bot for Wu Zhangjin
  2 siblings, 1 reply; 6+ messages in thread
From: Michal Marek @ 2010-10-28 21:05 UTC (permalink / raw)
  To: Wu Zhangjin
  Cc: rostedt, linux-kernel, mingo, John Reiser, Sam Ravnborg,
	linux-kbuild

On 27.10.2010 18:24, Wu Zhangjin wrote:
> From: Wu Zhangjin <wuzhangjin@gmail.com>
> 
> cmd_record_mcount is used to locate the _mcount symbols in the object
> files, only the files compiled with -pg has the _mcount symbol, so, it
> is only needed for such files, but the current cmd_record_mcount is used
> for all of the object files, so, we need to fix it and speed it up.
> 
> Since -pg may be removed by the method used in kernel/trace/Makefile:
> 
> ORIG_CFLAGS := $(KBUILD_CFLAGS)
> KBUILD_CFLAGS = $(subst -pg,,$(ORIG_CFLAGS))
> 
> Or may be removed by the method used in arch/x86/kernel/Makefile:
> 
> CONFIG_REMOVE_file.o = -pg

CFLAGS_REMOVE_file.o


> So, we must check the last variable stores the compiling flags, that is
> c_flags(Please refer to cmd_cc_o_c and rule_cc_o_c defined in
> scripts/Makefile.build) and since the CFLAGS_REMOVE_file.o is already
> filtered in _c_flags(Please refer to scripts/Makefile.lib) and _c_flags
> has less symbols, therefore, we only need to check _c_flags.
> 
> ---------------
> Changes from v1:
> 
>   o Don't touch Makefile for CONFIG_FTRACE_MCOUNT_RECORD is enough
>   o Use _c_flags intead of KBUILD_CFLAGS to cover CONFIG_REMOVE_file.o = -pg
>   (feedback from Steven Rostedt <rostedt@goodmis.org>)
> 
> Signed-off-by: Wu Zhangjin <wuzhangjin@gmail.com>

Acked-by: Michal Marek <mmarek@suse.cz>


> ---
>  scripts/Makefile.build |   13 +++++++++----
>  1 files changed, 9 insertions(+), 4 deletions(-)
> 
> diff --git a/scripts/Makefile.build b/scripts/Makefile.build
> index 5ad25e1..0ad6108 100644
> --- a/scripts/Makefile.build
> +++ b/scripts/Makefile.build
> @@ -214,17 +214,22 @@ ifdef BUILD_C_RECORDMCOUNT
>  # The empty.o file is created in the make process in order to determine
>  #  the target endianness and word size. It is made before all other C
>  #  files, including recordmcount.
> -cmd_record_mcount = if [ $(@) != "scripts/mod/empty.o" ]; then			\
> -			$(objtree)/scripts/recordmcount "$(@)";			\
> -		    fi;
> +sub_cmd_record_mcount =					\
> +	if [ $(@) != "scripts/mod/empty.o" ]; then	\
> +		$(objtree)/scripts/recordmcount "$(@)";	\
> +	fi;
>  else
> -cmd_record_mcount = set -e ; perl $(srctree)/scripts/recordmcount.pl "$(ARCH)" \
> +sub_cmd_record_mcount = set -e ; perl $(srctree)/scripts/recordmcount.pl "$(ARCH)" \
>  	"$(if $(CONFIG_CPU_BIG_ENDIAN),big,little)" \
>  	"$(if $(CONFIG_64BIT),64,32)" \
>  	"$(OBJDUMP)" "$(OBJCOPY)" "$(CC) $(KBUILD_CFLAGS)" \
>  	"$(LD)" "$(NM)" "$(RM)" "$(MV)" \
>  	"$(if $(part-of-module),1,0)" "$(@)";
>  endif
> +cmd_record_mcount = 						\
> +	if [ "$(findstring -pg,$(_c_flags))" == "-pg" ]; then	\
> +		$(sub_cmd_record_mcount)			\
> +	fi;
>  endif
>  
>  define rule_cc_o_c


^ permalink raw reply	[flat|nested] 6+ messages in thread

* Re: [v2 PATCH] ftrace: Speed up recordmcount
  2010-10-28 21:05 ` Michal Marek
@ 2010-11-09  5:35   ` wu zhangjin
  2010-11-09 13:53     ` Steven Rostedt
  0 siblings, 1 reply; 6+ messages in thread
From: wu zhangjin @ 2010-11-09  5:35 UTC (permalink / raw)
  To: rostedt
  Cc: linux-kernel, mingo, John Reiser, Sam Ravnborg, linux-kbuild,
	Michal Marek

Hi, Steve

On 10/29/10, Michal Marek <mmarek@suse.cz> wrote:
> On 27.10.2010 18:24, Wu Zhangjin wrote:
>> From: Wu Zhangjin <wuzhangjin@gmail.com>
>>
>> cmd_record_mcount is used to locate the _mcount symbols in the object
>> files, only the files compiled with -pg has the _mcount symbol, so, it
>> is only needed for such files, but the current cmd_record_mcount is used
>> for all of the object files, so, we need to fix it and speed it up.
>>
>> Since -pg may be removed by the method used in kernel/trace/Makefile:
>>
>> ORIG_CFLAGS := $(KBUILD_CFLAGS)
>> KBUILD_CFLAGS = $(subst -pg,,$(ORIG_CFLAGS))
>>
>> Or may be removed by the method used in arch/x86/kernel/Makefile:
>>
>> CONFIG_REMOVE_file.o = -pg
>
> CFLAGS_REMOVE_file.o
>

Did you apply this patch, should I fix this typo and resend it to you?

Best Regards,
Wu Zhangjin

>
>> So, we must check the last variable stores the compiling flags, that is
>> c_flags(Please refer to cmd_cc_o_c and rule_cc_o_c defined in
>> scripts/Makefile.build) and since the CFLAGS_REMOVE_file.o is already
>> filtered in _c_flags(Please refer to scripts/Makefile.lib) and _c_flags
>> has less symbols, therefore, we only need to check _c_flags.
>>
>> ---------------
>> Changes from v1:
>>
>>   o Don't touch Makefile for CONFIG_FTRACE_MCOUNT_RECORD is enough
>>   o Use _c_flags intead of KBUILD_CFLAGS to cover CONFIG_REMOVE_file.o =
>> -pg
>>   (feedback from Steven Rostedt <rostedt@goodmis.org>)
>>
>> Signed-off-by: Wu Zhangjin <wuzhangjin@gmail.com>
>
> Acked-by: Michal Marek <mmarek@suse.cz>
>
>
>> ---
>>  scripts/Makefile.build |   13 +++++++++----
>>  1 files changed, 9 insertions(+), 4 deletions(-)
>>
>> diff --git a/scripts/Makefile.build b/scripts/Makefile.build
>> index 5ad25e1..0ad6108 100644
>> --- a/scripts/Makefile.build
>> +++ b/scripts/Makefile.build
>> @@ -214,17 +214,22 @@ ifdef BUILD_C_RECORDMCOUNT
>>  # The empty.o file is created in the make process in order to determine
>>  #  the target endianness and word size. It is made before all other C
>>  #  files, including recordmcount.
>> -cmd_record_mcount = if [ $(@) != "scripts/mod/empty.o" ]; then			\
>> -			$(objtree)/scripts/recordmcount "$(@)";			\
>> -		    fi;
>> +sub_cmd_record_mcount =					\
>> +	if [ $(@) != "scripts/mod/empty.o" ]; then	\
>> +		$(objtree)/scripts/recordmcount "$(@)";	\
>> +	fi;
>>  else
>> -cmd_record_mcount = set -e ; perl $(srctree)/scripts/recordmcount.pl
>> "$(ARCH)" \
>> +sub_cmd_record_mcount = set -e ; perl $(srctree)/scripts/recordmcount.pl
>> "$(ARCH)" \
>>  	"$(if $(CONFIG_CPU_BIG_ENDIAN),big,little)" \
>>  	"$(if $(CONFIG_64BIT),64,32)" \
>>  	"$(OBJDUMP)" "$(OBJCOPY)" "$(CC) $(KBUILD_CFLAGS)" \
>>  	"$(LD)" "$(NM)" "$(RM)" "$(MV)" \
>>  	"$(if $(part-of-module),1,0)" "$(@)";
>>  endif
>> +cmd_record_mcount = 						\
>> +	if [ "$(findstring -pg,$(_c_flags))" == "-pg" ]; then	\
>> +		$(sub_cmd_record_mcount)			\
>> +	fi;
>>  endif
>>
>>  define rule_cc_o_c
>
>

^ permalink raw reply	[flat|nested] 6+ messages in thread

* Re: [v2 PATCH] ftrace: Speed up recordmcount
  2010-11-09  5:35   ` wu zhangjin
@ 2010-11-09 13:53     ` Steven Rostedt
  0 siblings, 0 replies; 6+ messages in thread
From: Steven Rostedt @ 2010-11-09 13:53 UTC (permalink / raw)
  To: wu zhangjin
  Cc: linux-kernel, mingo, John Reiser, Sam Ravnborg, linux-kbuild,
	Michal Marek

On Tue, 2010-11-09 at 13:35 +0800, wu zhangjin wrote:

> Did you apply this patch, should I fix this typo and resend it to you?

I applied it, but during testing it triggered a bug in the build system.

I'm looking into it. It is not really related to this patch, but I can't
submit it till the build is fix.

Also, since it is not that critical of a patch, I think I'll queue it
for 2.6.38, just to be safe.

Thanks,

-- Steve

^ permalink raw reply	[flat|nested] 6+ messages in thread

* [tip:perf/core] ftrace: Speed up recordmcount
  2010-10-27 16:24 [v2 PATCH] ftrace: Speed up recordmcount Wu Zhangjin
  2010-10-28  2:21 ` Steven Rostedt
  2010-10-28 21:05 ` Michal Marek
@ 2010-12-22 13:15 ` tip-bot for Wu Zhangjin
  2 siblings, 0 replies; 6+ messages in thread
From: tip-bot for Wu Zhangjin @ 2010-12-22 13:15 UTC (permalink / raw)
  To: linux-tip-commits
  Cc: linux-kernel, hpa, mingo, wuzhangjin, rostedt, mmarek, tglx

Commit-ID:  45677454dd6d128608117abe7dcd2bdfdd7cdf72
Gitweb:     http://git.kernel.org/tip/45677454dd6d128608117abe7dcd2bdfdd7cdf72
Author:     Wu Zhangjin <wuzhangjin@gmail.com>
AuthorDate: Thu, 28 Oct 2010 00:24:34 +0800
Committer:  Steven Rostedt <rostedt@goodmis.org>
CommitDate: Thu, 18 Nov 2010 17:16:05 -0500

ftrace: Speed up recordmcount

cmd_record_mcount is used to locate the _mcount symbols in the object
files, only the files compiled with -pg has the _mcount symbol, so, it
is only needed for such files, but the current cmd_record_mcount is used
for all of the object files, so, we need to fix it and speed it up.

Since -pg may be removed by the method used in kernel/trace/Makefile:

ORIG_CFLAGS := $(KBUILD_CFLAGS)
KBUILD_CFLAGS = $(subst -pg,,$(ORIG_CFLAGS))

Or may be removed by the method used in arch/x86/kernel/Makefile:

CFLAGS_REMOVE_file.o = -pg

So, we must check the last variable stores the compiling flags, that is
c_flags(Please refer to cmd_cc_o_c and rule_cc_o_c defined in
scripts/Makefile.build) and since the CFLAGS_REMOVE_file.o is already
filtered in _c_flags(Please refer to scripts/Makefile.lib) and _c_flags
has less symbols, therefore, we only need to check _c_flags.

---------------
Changes from v1:

  o Don't touch Makefile for CONFIG_FTRACE_MCOUNT_RECORD is enough
  o Use _c_flags intead of KBUILD_CFLAGS to cover CONFIG_REMOVE_file.o = -pg
  (feedback from Steven Rostedt <rostedt@goodmis.org>)

Acked-by: Michal Marek <mmarek@suse.cz>
Signed-off-by: Wu Zhangjin <wuzhangjin@gmail.com>
LKML-Reference: <3dc8cddf022eb7024f9f2cf857529a15bee8999a.1288196498.git.wuzhangjin@gmail.com>

[ changed if [ .. == .. ] to if [ .. = .. ] to handle dash environments ]

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
---
 scripts/Makefile.build |   13 +++++++++----
 1 files changed, 9 insertions(+), 4 deletions(-)

diff --git a/scripts/Makefile.build b/scripts/Makefile.build
index 5ad25e1..4eb99ab 100644
--- a/scripts/Makefile.build
+++ b/scripts/Makefile.build
@@ -214,17 +214,22 @@ ifdef BUILD_C_RECORDMCOUNT
 # The empty.o file is created in the make process in order to determine
 #  the target endianness and word size. It is made before all other C
 #  files, including recordmcount.
-cmd_record_mcount = if [ $(@) != "scripts/mod/empty.o" ]; then			\
-			$(objtree)/scripts/recordmcount "$(@)";			\
-		    fi;
+sub_cmd_record_mcount =					\
+	if [ $(@) != "scripts/mod/empty.o" ]; then	\
+		$(objtree)/scripts/recordmcount "$(@)";	\
+	fi;
 else
-cmd_record_mcount = set -e ; perl $(srctree)/scripts/recordmcount.pl "$(ARCH)" \
+sub_cmd_record_mcount = set -e ; perl $(srctree)/scripts/recordmcount.pl "$(ARCH)" \
 	"$(if $(CONFIG_CPU_BIG_ENDIAN),big,little)" \
 	"$(if $(CONFIG_64BIT),64,32)" \
 	"$(OBJDUMP)" "$(OBJCOPY)" "$(CC) $(KBUILD_CFLAGS)" \
 	"$(LD)" "$(NM)" "$(RM)" "$(MV)" \
 	"$(if $(part-of-module),1,0)" "$(@)";
 endif
+cmd_record_mcount = 						\
+	if [ "$(findstring -pg,$(_c_flags))" = "-pg" ]; then	\
+		$(sub_cmd_record_mcount)			\
+	fi;
 endif
 
 define rule_cc_o_c

^ permalink raw reply related	[flat|nested] 6+ messages in thread

end of thread, other threads:[~2010-12-22 13:16 UTC | newest]

Thread overview: 6+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2010-10-27 16:24 [v2 PATCH] ftrace: Speed up recordmcount Wu Zhangjin
2010-10-28  2:21 ` Steven Rostedt
2010-10-28 21:05 ` Michal Marek
2010-11-09  5:35   ` wu zhangjin
2010-11-09 13:53     ` Steven Rostedt
2010-12-22 13:15 ` [tip:perf/core] " tip-bot for Wu Zhangjin

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