[tip:perf/core] tracing: Forget about the NMI buffer for syscall events

From: tip-bot for Frederic Weisbecker
Date: Sun Nov 22 2009 - 03:44:11 EST


Commit-ID: 28889bf9e2db29747d58cd47a92d727f927c3aee
Gitweb: http://git.kernel.org/tip/28889bf9e2db29747d58cd47a92d727f927c3aee
Author: Frederic Weisbecker <fweisbec@xxxxxxxxx>
AuthorDate: Sun, 22 Nov 2009 05:21:33 +0100
Committer: Ingo Molnar <mingo@xxxxxxx>
CommitDate: Sun, 22 Nov 2009 09:03:42 +0100

tracing: Forget about the NMI buffer for syscall events

We are never in an NMI context when we commit a syscall trace to
perf. So just forget about the nmi buffer there.

Signed-off-by: Frederic Weisbecker <fweisbec@xxxxxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Cc: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
Cc: Paul Mackerras <paulus@xxxxxxxxx>
Cc: Steven Rostedt <rostedt@xxxxxxxxxxx>
Cc: Jason Baron <jbaron@xxxxxxxxxx>
LKML-Reference: <1258863695-10464-2-git-send-email-fweisbec@xxxxxxxxx>
Signed-off-by: Ingo Molnar <mingo@xxxxxxx>
---
kernel/trace/trace_syscalls.c | 10 ++--------
1 files changed, 2 insertions(+), 8 deletions(-)

diff --git a/kernel/trace/trace_syscalls.c b/kernel/trace/trace_syscalls.c
index 0bb9348..41b6dd9 100644
--- a/kernel/trace/trace_syscalls.c
+++ b/kernel/trace/trace_syscalls.c
@@ -511,10 +511,7 @@ static void prof_syscall_enter(struct pt_regs *regs, long id)

cpu = smp_processor_id();

- if (in_nmi())
- trace_buf = rcu_dereference(perf_trace_buf_nmi);
- else
- trace_buf = rcu_dereference(perf_trace_buf);
+ trace_buf = rcu_dereference(perf_trace_buf);

if (!trace_buf)
goto end;
@@ -617,10 +614,7 @@ static void prof_syscall_exit(struct pt_regs *regs, long ret)

cpu = smp_processor_id();

- if (in_nmi())
- trace_buf = rcu_dereference(perf_trace_buf_nmi);
- else
- trace_buf = rcu_dereference(perf_trace_buf);
+ trace_buf = rcu_dereference(perf_trace_buf);

if (!trace_buf)
goto end;
--
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