From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753981AbYJBL0T (ORCPT ); Thu, 2 Oct 2008 07:26:19 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752875AbYJBL0K (ORCPT ); Thu, 2 Oct 2008 07:26:10 -0400 Received: from fg-out-1718.google.com ([72.14.220.154]:27625 "EHLO fg-out-1718.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751983AbYJBL0J (ORCPT ); Thu, 2 Oct 2008 07:26:09 -0400 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=message-id:date:from:user-agent:mime-version:to:cc:subject :content-type:content-transfer-encoding; b=HZB1Zdo5sAPPpuDfqc5hXn32NgvFXmQktsw6vrXrm89LY5iMzxXh0ur984i7sJnMEz fM4udikLxgHXhFw20dMi2iv9vbl8raPgAp1CK6y9+ia1OdL6z9QlN18QCruLcFQD+bQX f1j5jgTZ4sWH+KNdJuK9XuvTxJZ48jRsOZyJ0= Message-ID: <48E4AFCD.9080004@gmail.com> Date: Thu, 02 Oct 2008 13:26:05 +0200 From: Frederic Weisbecker User-Agent: Thunderbird 2.0.0.16 (X11/20080724) MIME-Version: 1.0 To: Ingo Molnar CC: Steven Rostedt , linux-kernel@vger.kernel.org Subject: [PATCH -tip 2/2] Tracing/fastboot: Get the initcall name before it disappears Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org After some initcall traces, some initcall names may be inconsistent. That's because these functions will disappear from the .init section and also their name from the symbols table. So we have to copy the name of the function in a buffer large enough during the trace appending. It is not costly for the ring_buffer because the number of initcall entries is commonly not really large. Signed-off-by: Frederic Weisbecker --- include/linux/ftrace.h | 7 ++++--- init/main.c | 3 +-- kernel/trace/trace_boot.c | 14 ++++++++++---- 3 files changed, 15 insertions(+), 9 deletions(-) diff --git a/include/linux/ftrace.h b/include/linux/ftrace.h index 4455490..e672e51 100644 --- a/include/linux/ftrace.h +++ b/include/linux/ftrace.h @@ -7,6 +7,7 @@ #include #include #include +#include extern int ftrace_enabled; extern int @@ -213,7 +214,7 @@ ftrace_init_module(unsigned long *start, unsigned long *end) { } struct boot_trace { pid_t caller; - initcall_t func; + char func[KSYM_NAME_LEN]; int result; unsigned long long duration; ktime_t calltime; @@ -221,10 +222,10 @@ struct boot_trace { }; #ifdef CONFIG_BOOT_TRACER -extern void trace_boot(struct boot_trace *it); +extern void trace_boot(struct boot_trace *it, initcall_t fn); extern void start_boot_trace(void); #else -static inline void trace_boot(struct boot_trace *it) { } +static inline void trace_boot(struct boot_trace *it, initcall_t fn) { } static inline void start_boot_trace(void) { } #endif diff --git a/init/main.c b/init/main.c index ac3f760..47d621a 100644 --- a/init/main.c +++ b/init/main.c @@ -727,7 +727,6 @@ int do_one_initcall(initcall_t fn) if (initcall_debug) { it.caller = task_pid_nr(current); - it.func = fn; printk("calling %pF @ %i\n", fn, it.caller); it.calltime = ktime_get(); } @@ -740,7 +739,7 @@ int do_one_initcall(initcall_t fn) it.duration = (unsigned long long) delta.tv64 >> 20; printk("initcall %pF returned %d after %Ld msecs\n", fn, it.result, it.duration); - trace_boot(&it); + trace_boot(&it, fn); } msgbuf[0] = 0; diff --git a/kernel/trace/trace_boot.c b/kernel/trace/trace_boot.c index a8cb1c5..114fade 100644 --- a/kernel/trace/trace_boot.c +++ b/kernel/trace/trace_boot.c @@ -8,6 +8,7 @@ #include #include #include +#include #include "trace.h" @@ -56,17 +57,19 @@ static enum print_line_t initcall_print_line(struct trace_iterator *iter) struct timespec rettime = ktime_to_timespec(it->rettime); if (entry->type == TRACE_BOOT) { - ret = trace_seq_printf(s, "[%5ld.%06ld] calling %pF @ %i\n", + ret = trace_seq_printf(s, "[%5ld.%06ld] calling %s @ %i\n", calltime.tv_sec, calltime.tv_nsec, it->func, it->caller); if (!ret) return TRACE_TYPE_PARTIAL_LINE; - ret = trace_seq_printf(s, "[%5ld.%06ld] initcall %pF " + + ret = trace_seq_printf(s, "[%5ld.%06ld] initcall %s " "returned %d after %lld msecs\n", rettime.tv_sec, rettime.tv_nsec, it->func, it->result, it->duration); + if (!ret) return TRACE_TYPE_PARTIAL_LINE; return TRACE_TYPE_HANDLED; @@ -83,8 +86,7 @@ struct tracer boot_tracer __read_mostly = .print_line = initcall_print_line, }; - -void trace_boot(struct boot_trace *it) +void trace_boot(struct boot_trace *it, initcall_t fn) { struct ring_buffer_event *event; struct trace_boot *entry; @@ -95,6 +97,10 @@ void trace_boot(struct boot_trace *it) if (!trace_boot_enabled) return; + /* Get its name now since this function could + * disappear because it is in the .init section. + */ + sprint_symbol(it->func, (unsigned long)fn); preempt_disable(); data = tr->data[smp_processor_id()];