Revert "perf symbols: Demangle cloned functions"

This reverts commit de95ab5364.

Markus Trippelsdorf reported that this commit broke 'perf top':

 > I just see a gray screen with no text at all. Sometimes the
 > following error messages are printed:
 >
 >  *** Error in `perf': invalid fastbin entry (free): 0x00000000029b18c0
 >  ***
 >  *** Error in `perf': malloc(): memory corruption (fast): 0x0000000000ee0b10 ***

While this code is fixable, the commit itself fails on several levels:

 - it should have been a separate helper function
 - why the heck does it do strchr() twice
 - it casts a const char * over into char *
 - sloppy style
 - it's not even a regression fix!

So lets revert it and re-try the patch in v3.13.

Reported-by: Markus Trippelsdorf <markus@trippelsdorf.de>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
This commit is contained in:
Ingo Molnar 2013-09-29 16:12:54 +02:00
parent 9b565a8051
commit 14951f22f1

View File

@ -928,33 +928,8 @@ int dso__load_sym(struct dso *dso, struct map *map,
* to it...
*/
if (symbol_conf.demangle) {
/*
* The demangler doesn't deal with cloned functions.
* XXXX.clone.NUM or similar
* Strip the dot part and readd it later.
*/
char *p = (char *)elf_name, *dot;
dot = strchr(elf_name, '.');
if (dot) {
p = strdup(elf_name);
if (!p)
goto new_symbol;
dot = strchr(p, '.');
*dot = 0;
}
demangled = bfd_demangle(NULL, p,
demangled = bfd_demangle(NULL, elf_name,
DMGL_PARAMS | DMGL_ANSI);
if (dot)
*dot = '.';
if (demangled && dot) {
demangled = realloc(demangled, strlen(demangled) + strlen(dot) + 1);
if (!demangled)
goto new_symbol;
strcpy(demangled + (dot - p), dot);
}
if (p != elf_name)
free(p);
if (demangled != NULL)
elf_name = demangled;
}