perf symbols: avoid SyS kernel syscall aliases

When removing duplicate symbols, prefer to remove syscall aliases
starting with SyS or compat_SyS.

A side-effect of that is that it results in slightly improved results
for the "vmlinux symtab matches kallsyms" test.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Namhyung Kim <namhyung@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/r/1375875537-4509-6-git-send-email-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
This commit is contained in:
Adrian Hunter 2013-08-07 14:38:49 +03:00 committed by Arnaldo Carvalho de Melo
parent 2bbf03f16a
commit 3445432b7b
1 changed files with 14 additions and 3 deletions

View File

@ -87,6 +87,7 @@ static int choose_best_symbol(struct symbol *syma, struct symbol *symb)
{
s64 a;
s64 b;
size_t na, nb;
/* Prefer a symbol with non zero length */
a = syma->end - syma->start;
@ -120,11 +121,21 @@ static int choose_best_symbol(struct symbol *syma, struct symbol *symb)
else if (a > b)
return SYMBOL_B;
/* If all else fails, choose the symbol with the longest name */
if (strlen(syma->name) >= strlen(symb->name))
/* Choose the symbol with the longest name */
na = strlen(syma->name);
nb = strlen(symb->name);
if (na > nb)
return SYMBOL_A;
else
else if (na < nb)
return SYMBOL_B;
/* Avoid "SyS" kernel syscall aliases */
if (na >= 3 && !strncmp(syma->name, "SyS", 3))
return SYMBOL_B;
if (na >= 10 && !strncmp(syma->name, "compat_SyS", 10))
return SYMBOL_B;
return SYMBOL_A;
}
void symbols__fixup_duplicate(struct rb_root *symbols)