Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757933AbZCYJVQ (ORCPT ); Wed, 25 Mar 2009 05:21:16 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752188AbZCYJU7 (ORCPT ); Wed, 25 Mar 2009 05:20:59 -0400 Received: from cn.fujitsu.com ([222.73.24.84]:54860 "EHLO song.cn.fujitsu.com" rhost-flags-OK-FAIL-OK-OK) by vger.kernel.org with ESMTP id S1751420AbZCYJU7 (ORCPT ); Wed, 25 Mar 2009 05:20:59 -0400 Message-ID: <49C9F796.9040503@cn.fujitsu.com> Date: Wed, 25 Mar 2009 17:21:26 +0800 From: Li Zefan User-Agent: Thunderbird 2.0.0.9 (X11/20071115) MIME-Version: 1.0 To: Ingo Molnar CC: Jens Axboe , Arnaldo Carvalho de Melo , Steven Rostedt , Frederic Weisbecker , LKML Subject: [PATCH 3/3] blktrace: fix the original blktrace References: <49C9F700.9070609@cn.fujitsu.com> In-Reply-To: <49C9F700.9070609@cn.fujitsu.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2673 Lines: 89 Currently the original blktrace, which is using relay and is used via ioctl, is broken. You can use ftrace to see the output of blktrace, but user-space blktrace is unusable. It's broken by "blktrace: add ftrace plugin" (c71a896154119f4ca9e89d6078f5f63ad60ef199) ======== @@ -131,13 +162,14 @@ static void __blk_add_trace() - if (unlikely(bt->trace_state != Blktrace_running)) + if (unlikely(bt->trace_state != Blktrace_running || !blk_tracer_enabled)) return; ========= With this patch, both ioctl and ftrace can be used, but of course you can't use both of them at the same time. Signed-off-by: Li Zefan --- kernel/trace/blktrace.c | 12 +++++------- 1 files changed, 5 insertions(+), 7 deletions(-) diff --git a/kernel/trace/blktrace.c b/kernel/trace/blktrace.c index 95f89fa..a7f7ff5 100644 --- a/kernel/trace/blktrace.c +++ b/kernel/trace/blktrace.c @@ -110,7 +110,7 @@ void __trace_note_message(struct blk_trace *bt, const char *fmt, ...) unsigned long flags; char *buf; - if (blk_tr) { + if (blk_tracer_enabled) { va_start(args, fmt); ftrace_vprintk(fmt, args); va_end(args); @@ -169,7 +169,7 @@ static void __blk_add_trace(struct blk_trace *bt, sector_t sector, int bytes, pid_t pid; int cpu, pc = 0; - if (unlikely(bt->trace_state != Blktrace_running || + if (unlikely(bt->trace_state != Blktrace_running && !blk_tracer_enabled)) return; @@ -185,7 +185,7 @@ static void __blk_add_trace(struct blk_trace *bt, sector_t sector, int bytes, return; cpu = raw_smp_processor_id(); - if (blk_tr) { + if (blk_tracer_enabled) { tracing_record_cmdline(current); pc = preempt_count(); @@ -235,7 +235,7 @@ record_it: if (pdu_len) memcpy((void *) t + sizeof(*t), pdu_data, pdu_len); - if (blk_tr) { + if (blk_tracer_enabled) { trace_buffer_unlock_commit(blk_tr, event, 0, pc); return; } @@ -267,8 +267,7 @@ int blk_trace_remove(struct request_queue *q) if (!bt) return -EINVAL; - if (bt->trace_state == Blktrace_setup || - bt->trace_state == Blktrace_stopped) + if (bt->trace_state != Blktrace_running) blk_trace_cleanup(bt); return 0; @@ -1273,7 +1272,6 @@ static int blk_trace_setup_queue(struct request_queue *q, dev_t dev) bt->dev = dev; bt->act_mask = (u16)-1; bt->end_lba = -1ULL; - bt->trace_state = Blktrace_running; old_bt = xchg(&q->blk_trace, bt); if (old_bt != NULL) { -- 1.5.4.rc3 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/