ftrace/x86: Add support for C version of recordmcount

This patch adds the support for the C version of recordmcount and
compile times show ~ 12% improvement.

After verifying this works, other archs can add:

 HAVE_C_MCOUNT_RECORD

in its Kconfig and it will use the C version of recordmcount
instead of the perl version.

Cc: <linux-arch@vger.kernel.org>
Cc: Michal Marek <mmarek@suse.cz>
Cc: linux-kbuild@vger.kernel.org
Cc: John Reiser <jreiser@bitwagon.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
This commit is contained in:
Steven Rostedt 2010-10-13 17:12:30 -04:00 committed by Steven Rostedt
parent 81d3858d31
commit 72441cb1fd
5 changed files with 17 additions and 0 deletions

View File

@ -568,6 +568,12 @@ endif
ifdef CONFIG_FUNCTION_TRACER
KBUILD_CFLAGS += -pg
ifdef CONFIG_DYNAMIC_FTRACE
ifdef CONFIG_HAVE_C_MCOUNT_RECORD
BUILD_C_RECORDMCOUNT := y
export BUILD_C_RECORDMCOUNT
endif
endif
endif
# We trigger additional mismatches with less inlining

View File

@ -33,6 +33,7 @@ config X86
select HAVE_KRETPROBES
select HAVE_OPTPROBES
select HAVE_FTRACE_MCOUNT_RECORD
select HAVE_C_MCOUNT_RECORD
select HAVE_DYNAMIC_FTRACE
select HAVE_FUNCTION_TRACER
select HAVE_FUNCTION_GRAPH_TRACER

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@ -49,6 +49,11 @@ config HAVE_SYSCALL_TRACEPOINTS
help
See Documentation/trace/ftrace-design.txt
config HAVE_C_MCOUNT_RECORD
bool
help
C version of recordmcount available?
config TRACER_MAX_TRACE
bool

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@ -11,6 +11,7 @@ hostprogs-$(CONFIG_KALLSYMS) += kallsyms
hostprogs-$(CONFIG_LOGO) += pnmtologo
hostprogs-$(CONFIG_VT) += conmakehash
hostprogs-$(CONFIG_IKCONFIG) += bin2c
hostprogs-$(BUILD_C_RECORDMCOUNT) += recordmcount
always := $(hostprogs-y) $(hostprogs-m)

View File

@ -209,12 +209,16 @@ cmd_modversions = \
endif
ifdef CONFIG_FTRACE_MCOUNT_RECORD
ifdef BUILD_C_RECORDMCOUNT
cmd_record_mcount = $(srctree)/scripts/recordmcount "$(@)";
else
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)" "$(LD)" "$(NM)" "$(RM)" "$(MV)" \
"$(if $(part-of-module),1,0)" "$(@)";
endif
endif
define rule_cc_o_c
$(call echo-cmd,checksrc) $(cmd_checksrc) \