mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-08-21 08:19:28 +00:00
![Rasmus Villemoes](/assets/img/avatar_default.png)
The current checkstack.pl script has a few problems, stemming from the overly simplistic attempt at parsing objdump output with regular expressions: 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 KCFLAGS set to -fstack-usage. Example use is scripts/stackusage -o out.su -j8 lib/ The script understands "-o foo" for writing to 'foo' and -h for a trivial help text; anything else is passed to make. Afterwards, we find all newly created .su files, massage them a little, sort by stack use and write the result to a single output file. Note that the function names printed by (at least) gcc 4.7 are sometimes useless. For example, the first three lines of out.su generated above are ./lib/decompress_bunzip2.c:155 get_next_block 448 static ./lib/decompress_unlzma.c:537 unlzma 336 static ./lib/vsprintf.c:616 8 304 static That function '8' is really the static symbol_string(), but it has been subject to 'interprocedural scalar replacement of aggregates', so its name in the object file is 'symbol_string.isra.8'. gcc 5.0 doesn't have this problem; it uses the full name as seen in the object 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> Signed-off-by: Michal Marek <mmarek@suse.com>
33 lines
759 B
Bash
Executable file
33 lines
759 B
Bash
Executable file
#!/bin/sh
|
|
|
|
outfile=""
|
|
now=`date +%s`
|
|
|
|
while [ $# -gt 0 ]
|
|
do
|
|
case "$1" in
|
|
-o)
|
|
outfile="$2"
|
|
shift 2;;
|
|
-h)
|
|
echo "usage: $0 [-o outfile] <make options/args>"
|
|
exit 0;;
|
|
*) break;;
|
|
esac
|
|
done
|
|
|
|
if [ -z "$outfile" ]
|
|
then
|
|
outfile=`mktemp --tmpdir stackusage.$$.XXXX`
|
|
fi
|
|
|
|
KCFLAGS="${KCFLAGS} -fstack-usage" make "$@"
|
|
|
|
# Prepend directory name to file names, remove column information,
|
|
# make file:line/function/size/type properly tab-separated.
|
|
find . -name '*.su' -newermt "@${now}" -print | \
|
|
xargs perl -MFile::Basename -pe \
|
|
'$d = dirname($ARGV); s#([^:]+:[0-9]+):[0-9]+:#$d/$1\t#;' | \
|
|
sort -k3,3nr > "${outfile}"
|
|
|
|
echo "$0: output written to ${outfile}"
|