From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933574Ab2BBUB3 (ORCPT ); Thu, 2 Feb 2012 15:01:29 -0500 Received: from mail-gy0-f202.google.com ([209.85.160.202]:53704 "EHLO mail-gy0-f202.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933558Ab2BBUBZ (ORCPT ); Thu, 2 Feb 2012 15:01:25 -0500 From: Vaibhav Nagarnaik To: Steven Rostedt , Frederic Weisbecker , Ingo Molnar Cc: Michael Rubin , David Sharp , Justin Teravest , linux-kernel@vger.kernel.org, Vaibhav Nagarnaik Subject: [PATCH v5 4/4] trace: change CPU ring buffer state from tracing_cpumask Date: Thu, 2 Feb 2012 12:00:44 -0800 Message-Id: <1328212844-11889-4-git-send-email-vnagarnaik@google.com> X-Mailer: git-send-email 1.7.7.3 In-Reply-To: <1328212844-11889-1-git-send-email-vnagarnaik@google.com> References: <1318382410-14967-1-git-send-email-vnagarnaik@google.com> <1328212844-11889-1-git-send-email-vnagarnaik@google.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org According to Documentation/trace/ftrace.txt: tracing_cpumask: This is a mask that lets the user only trace on specified CPUS. The format is a hex string representing the CPUS. The tracing_cpumask currently doesn't affect the tracing state of per-CPU ring buffers. This patch enables/disables CPU recording as its corresponding bit in tracing_cpumask is set/unset. Signed-off-by: Vaibhav Nagarnaik --- kernel/trace/trace.c | 2 ++ 1 files changed, 2 insertions(+), 0 deletions(-) diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index abf1108..e25672e 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -2592,10 +2592,12 @@ tracing_cpumask_write(struct file *filp, const char __user *ubuf, if (cpumask_test_cpu(cpu, tracing_cpumask) && !cpumask_test_cpu(cpu, tracing_cpumask_new)) { atomic_inc(&global_trace.data[cpu]->disabled); + ring_buffer_record_disable_cpu(global_trace.buffer, cpu); } if (!cpumask_test_cpu(cpu, tracing_cpumask) && cpumask_test_cpu(cpu, tracing_cpumask_new)) { atomic_dec(&global_trace.data[cpu]->disabled); + ring_buffer_record_enable_cpu(global_trace.buffer, cpu); } } arch_spin_unlock(&ftrace_max_lock); -- 1.7.7.3