perf/x86/64: Do report user_regs->cx while we are in syscall, in get_regs_user()
authorDenys Vlasenko <dvlasenk@redhat.com>
Fri, 10 Apr 2015 13:06:57 +0000 (15:06 +0200)
committerIngo Molnar <mingo@kernel.org>
Sat, 11 Apr 2015 11:08:53 +0000 (13:08 +0200)
Yes, it is true that cx contains return address.
It's not clear why we trash it.
Stop doing that.

Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1428671219-29341-2-git-send-email-dvlasenk@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
arch/x86/kernel/perf_regs.c

index 7ab198acc5b87761c392975e21c4907d9304d23c..a8d4e4862ace93ac0faa6bc18c1061dda892f28a 100644 (file)
@@ -177,8 +177,6 @@ void perf_get_regs_user(struct perf_regs *regs_user,
                 * than just blindly copying user_regs.
                 */
                regs_user->abi = PERF_SAMPLE_REGS_ABI_64;
-               /* usually contains return address (same as ->ip) */
-               regs_user_copy->cx = -1;
        } else {
                /* We're probably in an interrupt or exception. */
                regs_user->abi = user_64bit_mode(user_regs) ?