| Message ID | 1434849046-19920-2-git-send-email-linux@rasmusvillemoes.dk (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On 2015-06-21 03:10, Rasmus Villemoes wrote: > The current checkstack.pl script has a few problems, stemming from the > overly simplistic attempt at parsing objdump output with regular > expresions: For example, on x86_64 it doesn't take the push > instruction into account, making it consistently underestimate the > real stack use, and it also doesn't capture stack pointer adjustments > of exactly 128 bytes [1]. > > Since newer gcc (>= 4.6) knows about -fstack-usage, we might as well > take the information straight from the horse's mouth. This patch > introduces scripts/stackusage, which is a simple wrapper for running > make with EXTRA_CFLAGS set to -fstack-usage. Example use is > > scripts/stackusage -o out.su -- -j8 fs/ext4/ > > Arguments after -- are passed to make. Afterwards, we find all newly > created .su files, massage them a little, sort by stack use and > concatenate the result to a single output file. > > [1] Since gcc encodes that by > > 48 83 c4 80 add $0xffffffffffffff80,%rsp > > and not > > 48 81 ec 80 00 00 00 sub $0x80,%rsp > > since -128 fits in an imm8. > > Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> > --- > scripts/stackusage | 40 ++++++++++++++++++++++++++++++++++++++++ > 1 file changed, 40 insertions(+) > create mode 100755 scripts/stackusage > > diff --git a/scripts/stackusage b/scripts/stackusage > new file mode 100755 > index 000000000000..d631af648ae7 > --- /dev/null > +++ b/scripts/stackusage > @@ -0,0 +1,40 @@ > +#!/bin/sh > + > +outfile="" > +now=`date +%s` > + > +while [ $# -gt 0 ] > +do > + case "$1" in > + -o) > + outfile="$2" > + echo "$outfile" > + shift 2;; > + -h) > + echo "usage: $0 [-o outfile] -- <make options/args>" > + exit 0;; > + --) > + shift > + break;; > + -*) > + echo >&2 "usage: $0 [-o outfile] -- <make options/args>" > + exit 1;; > + *) break;; > + esac > +done > + > +if [ -z "$outfile" ] > +then > + outfile=`mktemp --tmpdir stackusage.$$.XXXX` > +fi > + > +make EXTRA_CFLAGS="-fstack-usage" "$@" EXTRA_CFLAGS is reserved for use by Makefiles, please use KCFLAGS instead. I wonder whether it worked at all, because EXTRA_CFLAGS is reset by scripts/Makefile.build. Michal -- To unsubscribe from this list: send the line "unsubscribe linux-kbuild" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Tue, Jun 23 2015, Michal Marek <mmarek@suse.cz> wrote: > > EXTRA_CFLAGS is reserved for use by Makefiles, please use KCFLAGS > instead. Will do, thanks. Maybe Documentation/SubmitChecklist and Documentation/development-process/4.Coding wants to be updated. > I wonder whether it worked at all, because EXTRA_CFLAGS is > reset by scripts/Makefile.build. It did indeed work, but only because I passed the setting on the make command line and not via the environment. I think one needs an override directive to actually override the settings from the command line: $ cat Makefile VAR1 := a1 VAR2 := a2 override VAR3 := a3 override VAR4 := a4 all: @echo $(VAR1) $(VAR2) $(VAR3) $(VAR4) $ VAR1=b1 VAR3=b3 make VAR2=b2 VAR4=b4 all a1 b2 a3 a4 -- To unsubscribe from this list: send the line "unsubscribe linux-kbuild" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/scripts/stackusage b/scripts/stackusage new file mode 100755 index 000000000000..d631af648ae7 --- /dev/null +++ b/scripts/stackusage @@ -0,0 +1,40 @@ +#!/bin/sh + +outfile="" +now=`date +%s` + +while [ $# -gt 0 ] +do + case "$1" in + -o) + outfile="$2" + echo "$outfile" + shift 2;; + -h) + echo "usage: $0 [-o outfile] -- <make options/args>" + exit 0;; + --) + shift + break;; + -*) + echo >&2 "usage: $0 [-o outfile] -- <make options/args>" + exit 1;; + *) break;; + esac +done + +if [ -z "$outfile" ] +then + outfile=`mktemp --tmpdir stackusage.$$.XXXX` +fi + +make EXTRA_CFLAGS="-fstack-usage" "$@" + +# Prepend directory name to file names, remove line/column +# information, make file/function/size/type properly tab-separated. +find . -name '*.su' -newermt "@${now}" -print | \ + xargs perl -MFile::Basename -pe \ + '$d = dirname($ARGV); s#([^:]+):([0-9]+:){2}#$d/$1\t#;' | \ + sort -k3,3nr > "${outfile}" + +echo "$0: output written to ${outfile}"
The current checkstack.pl script has a few problems, stemming from the overly simplistic attempt at parsing objdump output with regular expresions: For example, on x86_64 it doesn't take the push instruction into account, making it consistently underestimate the real stack use, and it also doesn't capture stack pointer adjustments of exactly 128 bytes [1]. Since newer gcc (>= 4.6) knows about -fstack-usage, we might as well take the information straight from the horse's mouth. This patch introduces scripts/stackusage, which is a simple wrapper for running make with EXTRA_CFLAGS set to -fstack-usage. Example use is scripts/stackusage -o out.su -- -j8 fs/ext4/ Arguments after -- are passed to make. Afterwards, we find all newly created .su files, massage them a little, sort by stack use and concatenate the result to a single output file. [1] Since gcc encodes that by 48 83 c4 80 add $0xffffffffffffff80,%rsp and not 48 81 ec 80 00 00 00 sub $0x80,%rsp since -128 fits in an imm8. Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> --- scripts/stackusage | 40 ++++++++++++++++++++++++++++++++++++++++ 1 file changed, 40 insertions(+) create mode 100755 scripts/stackusage