Commit 14951f22 authored Sep 29, 2013 by Ingo Molnar

Revert "perf symbols: Demangle cloned functions"



This reverts commit de95ab53.

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>

parent 9b565a80

tools/perf/util/symbol-elf.c

+1 −26

Original line number	Original line	Diff line number	Diff line
	@@ -928,33 +928,8 @@ int dso__load_sym(struct dso dso, struct map map,
	* to it...		* to it...
	*/		*/
	if (symbol_conf.demangle) {		if (symbol_conf.demangle) {
	/*		demangled = bfd_demangle(NULL, elf_name,
	* 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,
	DMGL_PARAMS \| DMGL_ANSI);		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)		if (demangled != NULL)
	elf_name = demangled;		elf_name = demangled;
	}		}