From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1761577AbZAHUha (ORCPT ); Thu, 8 Jan 2009 15:37:30 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1755230AbZAHUhU (ORCPT ); Thu, 8 Jan 2009 15:37:20 -0500 Received: from mail-ew0-f17.google.com ([209.85.219.17]:57888 "EHLO mail-ew0-f17.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755056AbZAHUhS convert rfc822-to-8bit (ORCPT ); Thu, 8 Jan 2009 15:37:18 -0500 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=sender:date:from:to:cc:subject:message-id:in-reply-to:references :x-mailer:mime-version:content-type:content-transfer-encoding; b=iDPVnnw0z3k4Q3y2zfbTRWlzi8v6m+NM0NSrJKgnKdBk1e1rntECTyaf4fSjJkWIx3 RwVFbrL1MumYauxi5kWugEqS1vwqkZ6ZXOa8mSZjHzXSgj/SsF80jR+OJWXr+OWt0iFf DVM74xZshKBH/9UJ/DzBYRGNRMa5/9VDKwHDs= Date: Thu, 8 Jan 2009 22:37:11 +0200 From: Pekka Paalanen To: Ingo Molnar Cc: Pekka Paalanen , Peter Zijlstra , linux-kernel , Steven Rostedt Subject: [PATCH 3/3] mmiotrace: count events lost due to not recording Message-ID: <20090108223711.48d4b8a2@daedalus.pq.iki.fi> In-Reply-To: <20090108223255.6f29f1cf@daedalus.pq.iki.fi> References: <20090108223255.6f29f1cf@daedalus.pq.iki.fi> X-Mailer: Claws Mail 3.6.1 (GTK+ 2.12.11; x86_64-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 8BIT Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org >>From 8fbe1e5f24a2ffb173b900c0d54c771b1fa13446 Mon Sep 17 00:00:00 2001 From: Pekka Paalanen Date: Tue, 6 Jan 2009 13:57:11 +0200 Subject: [PATCH] mmiotrace: count events lost due to not recording The tracing framework, or the ring buffer facility it uses, has a switch to stop recording data. When recording is off, the trace events will be lost. The framework does not count these, so mmiotrace has to count them itself. Signed-off-by: Pekka Paalanen --- kernel/trace/trace_mmiotrace.c | 14 ++++++++++---- 1 files changed, 10 insertions(+), 4 deletions(-) diff --git a/kernel/trace/trace_mmiotrace.c b/kernel/trace/trace_mmiotrace.c index fcec59f..621c8c3 100644 --- a/kernel/trace/trace_mmiotrace.c +++ b/kernel/trace/trace_mmiotrace.c @@ -9,6 +9,7 @@ #include #include #include +#include #include "trace.h" #include "trace_output.h" @@ -20,6 +21,7 @@ struct header_iter { static struct trace_array *mmio_trace_array; static bool overrun_detected; static unsigned long prev_overruns; +static atomic_t dropped_count; static void mmio_reset_data(struct trace_array *tr) { @@ -122,11 +124,11 @@ static void mmio_close(struct trace_iterator *iter) static unsigned long count_overruns(struct trace_iterator *iter) { - unsigned long cnt = 0; + unsigned long cnt = atomic_xchg(&dropped_count, 0); unsigned long over = ring_buffer_overruns(iter->tr->buffer); if (over > prev_overruns) - cnt = over - prev_overruns; + cnt += over - prev_overruns; prev_overruns = over; return cnt; } @@ -308,8 +310,10 @@ static void __trace_mmiotrace_rw(struct trace_array *tr, event = ring_buffer_lock_reserve(tr->buffer, sizeof(*entry), &irq_flags); - if (!event) + if (!event) { + atomic_inc(&dropped_count); return; + } entry = ring_buffer_event_data(event); tracing_generic_entry_update(&entry->ent, 0, preempt_count()); entry->ent.type = TRACE_MMIO_RW; @@ -336,8 +340,10 @@ static void __trace_mmiotrace_map(struct trace_array *tr, event = ring_buffer_lock_reserve(tr->buffer, sizeof(*entry), &irq_flags); - if (!event) + if (!event) { + atomic_inc(&dropped_count); return; + } entry = ring_buffer_event_data(event); tracing_generic_entry_update(&entry->ent, 0, preempt_count()); entry->ent.type = TRACE_MMIO_MAP; -- 1.6.0.6