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author | 2016-04-19 00:07:18 +0100 | |
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committer | 2016-04-19 12:37:01 -0300 | |
commit | f56ebf20d0f535f5da7cfcf0000ab3e0af133f81 (patch) | |
tree | c16b20d2ce80a30231e0b2730910602b7f757c6a /tools/perf/util/jitdump.c | |
parent | perf script: Fix postgresql ubuntu install instructions (diff) | |
download | linux-f56ebf20d0f535f5da7cfcf0000ab3e0af133f81.tar.gz linux-f56ebf20d0f535f5da7cfcf0000ab3e0af133f81.tar.bz2 linux-f56ebf20d0f535f5da7cfcf0000ab3e0af133f81.zip |
perf jit: memset() variable 'st' using the correct size
The current code is memsetting the 'struct stat' variable 'st' with the size of
'stat' (which turns out to be 1 byte) rather than the size of variable 'sz'.
Committer notes:
sizeof(function) isn't valid, the result depends on the compiler used, with
gcc, enabling pedantic warnings we get:
$ cat sizeof_function.c
#include <sys/types.h>
#include <sys/stat.h>
#include <unistd.h>
#include <stdio.h>
int main(void)
{
printf("sizeof(stat)=%zd, stat=%p\n", sizeof(stat), stat);
return 0;
}
$ readelf -sW sizeof_function | grep -w stat
49: 0000000000400630 16 FUNC WEAK HIDDEN 13 stat
$ cc -pedantic sizeof_function.c -o sizeof_function
sizeof_function.c: In function ‘main’:
sizeof_function.c:8:46: warning: invalid application of ‘sizeof’ to a function type [-Wpointer-arith]
printf("sizeof(stat)=%zd, stat=%p\n", sizeof(stat), stat);
^
$ ./sizeof_function
sizeof(stat)=1, stat=0x400630
$
Standard C, section 6.5.3.4:
"The sizeof operator shall not be applied to an expression that has function
type or an incomplete type, to the parenthesized name of such a type,
or to an expression that designates a bit-field member."
http://www.open-std.org/jtc1/sc22/wg14/www/docs/n1256.pdf
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Fixes: 9b07e27f88b9 ("perf inject: Add jitdump mmap injection support")
Link: http://lkml.kernel.org/r/1461020838-9260-1-git-send-email-colin.king@canonical.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Diffstat (limited to 'tools/perf/util/jitdump.c')
-rw-r--r-- | tools/perf/util/jitdump.c | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/tools/perf/util/jitdump.c b/tools/perf/util/jitdump.c index 52fcef3074fe..86afe9618bb0 100644 --- a/tools/perf/util/jitdump.c +++ b/tools/perf/util/jitdump.c @@ -412,7 +412,7 @@ static int jit_repipe_code_load(struct jit_buf_desc *jd, union jr_entry *jr) return -1; } if (stat(filename, &st)) - memset(&st, 0, sizeof(stat)); + memset(&st, 0, sizeof(st)); event->mmap2.header.type = PERF_RECORD_MMAP2; event->mmap2.header.misc = PERF_RECORD_MISC_USER; @@ -500,7 +500,7 @@ static int jit_repipe_code_move(struct jit_buf_desc *jd, union jr_entry *jr) size++; /* for \0 */ if (stat(filename, &st)) - memset(&st, 0, sizeof(stat)); + memset(&st, 0, sizeof(st)); size = PERF_ALIGN(size, sizeof(u64)); |