From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752598AbZBCCpA (ORCPT ); Mon, 2 Feb 2009 21:45:00 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751489AbZBCCoC (ORCPT ); Mon, 2 Feb 2009 21:44:02 -0500 Received: from hrndva-omtalb.mail.rr.com ([71.74.56.122]:53888 "EHLO hrndva-omtalb.mail.rr.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751221AbZBCCn7 (ORCPT ); Mon, 2 Feb 2009 21:43:59 -0500 Message-Id: <20090203024358.531245194@goodmis.org> References: <20090203023830.440860800@goodmis.org> User-Agent: quilt/0.46-1 Date: Mon, 02 Feb 2009 21:38:33 -0500 From: Steven Rostedt To: linux-kernel@vger.kernel.org Cc: Ingo Molnar , Andrew Morton , Peter Zijlstra , Frederic Weisbecker , Arjan van de Ven , Steven Rostedt Subject: [PATCH 3/3] trace: let boot trace be chosen by command line Content-Disposition: inline; filename=0003-trace-let-boot-trace-be-chosen-by-command-line.patch Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Steven Rostedt Now that we have a working ftrace= function, make the boot tracer get activated by it. This way we can turn it on or off without recompiling the kernel, as well as keeping the selftests on. The selftests are disabled whenever a default tracer starts running. Signed-off-by: Steven Rostedt --- kernel/trace/Kconfig | 7 +++---- kernel/trace/trace.c | 5 +---- kernel/trace/trace_boot.c | 11 +++++++---- 3 files changed, 11 insertions(+), 12 deletions(-) diff --git a/kernel/trace/Kconfig b/kernel/trace/Kconfig index 2780665..8115daf 100644 --- a/kernel/trace/Kconfig +++ b/kernel/trace/Kconfig @@ -164,9 +164,8 @@ config BOOT_TRACER representation of the delays during initcalls - but the raw /debug/tracing/trace text output is readable too. - ( Note that tracing self tests can't be enabled if this tracer is - selected, because the self-tests are an initcall as well and that - would invalidate the boot trace. ) + You must pass in ftrace=initcall to the kernel command line + to enable this on bootup. config TRACE_BRANCH_PROFILING bool "Trace likely/unlikely profiler" @@ -328,7 +327,7 @@ config FTRACE_SELFTEST config FTRACE_STARTUP_TEST bool "Perform a startup test on ftrace" - depends on TRACING && DEBUG_KERNEL && !BOOT_TRACER + depends on TRACING && DEBUG_KERNEL select FTRACE_SELFTEST help This option performs a series of startup tests on ftrace. On bootup diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index 2c720c7..40edef4 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -3167,12 +3167,9 @@ __init static int tracer_alloc_buffers(void) trace_init_cmdlines(); register_tracer(&nop_trace); + current_trace = &nop_trace; #ifdef CONFIG_BOOT_TRACER register_tracer(&boot_tracer); - current_trace = &boot_tracer; - current_trace->init(&global_trace); -#else - current_trace = &nop_trace; #endif /* All seems OK, enable tracing */ tracing_disabled = 0; diff --git a/kernel/trace/trace_boot.c b/kernel/trace/trace_boot.c index 0e94b3d..1f07895 100644 --- a/kernel/trace/trace_boot.c +++ b/kernel/trace/trace_boot.c @@ -28,13 +28,13 @@ void start_boot_trace(void) void enable_boot_trace(void) { - if (pre_initcalls_finished) + if (boot_trace && pre_initcalls_finished) tracing_start_sched_switch_record(); } void disable_boot_trace(void) { - if (pre_initcalls_finished) + if (boot_trace && pre_initcalls_finished) tracing_stop_sched_switch_record(); } @@ -43,6 +43,9 @@ static int boot_trace_init(struct trace_array *tr) int cpu; boot_trace = tr; + if (!tr) + return 0; + for_each_cpu(cpu, cpu_possible_mask) tracing_reset(tr, cpu); @@ -132,7 +135,7 @@ void trace_boot_call(struct boot_trace_call *bt, initcall_t fn) unsigned long irq_flags; struct trace_array *tr = boot_trace; - if (!pre_initcalls_finished) + if (!tr || !pre_initcalls_finished) return; /* Get its name now since this function could @@ -164,7 +167,7 @@ void trace_boot_ret(struct boot_trace_ret *bt, initcall_t fn) unsigned long irq_flags; struct trace_array *tr = boot_trace; - if (!pre_initcalls_finished) + if (!tr || !pre_initcalls_finished) return; sprint_symbol(bt->func, (unsigned long)fn); -- 1.5.6.5 --