From patchwork Fri Sep 9 09:37:01 2011 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Stefan Hajnoczi X-Patchwork-Id: 114034 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from lists.gnu.org (lists.gnu.org [140.186.70.17]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (Client did not present a certificate) by ozlabs.org (Postfix) with ESMTPS id 6933FB6FAF for ; Fri, 9 Sep 2011 19:37:26 +1000 (EST) Received: from localhost ([::1]:55615 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1R1xWT-0000C9-2m for incoming@patchwork.ozlabs.org; Fri, 09 Sep 2011 05:37:21 -0400 Received: from eggs.gnu.org ([140.186.70.92]:41181) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1R1xWH-00006M-Or for qemu-devel@nongnu.org; Fri, 09 Sep 2011 05:37:12 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1R1xWG-0008HP-Il for qemu-devel@nongnu.org; Fri, 09 Sep 2011 05:37:09 -0400 Received: from mtagate7.uk.ibm.com ([194.196.100.167]:45660) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1R1xWG-0008GS-AH for qemu-devel@nongnu.org; Fri, 09 Sep 2011 05:37:08 -0400 Received: from d06nrmr1707.portsmouth.uk.ibm.com (d06nrmr1707.portsmouth.uk.ibm.com [9.149.39.225]) by mtagate7.uk.ibm.com (8.13.1/8.13.1) with ESMTP id p899b61W004934 for ; Fri, 9 Sep 2011 09:37:06 GMT Received: from d06av06.portsmouth.uk.ibm.com (d06av06.portsmouth.uk.ibm.com [9.149.37.217]) by d06nrmr1707.portsmouth.uk.ibm.com (8.13.8/8.13.8/NCO v10.0) with ESMTP id p899b6tI2367690 for ; Fri, 9 Sep 2011 10:37:06 +0100 Received: from d06av06.portsmouth.uk.ibm.com (loopback [127.0.0.1]) by d06av06.portsmouth.uk.ibm.com (8.14.4/8.13.1/NCO v10.0 AVout) with ESMTP id p899b6Qf006145 for ; Fri, 9 Sep 2011 03:37:06 -0600 Received: from stefanha-thinkpad.manchester-maybrook.uk.ibm.com (dyn-9-174-219-30.manchester-maybrook.uk.ibm.com [9.174.219.30]) by d06av06.portsmouth.uk.ibm.com (8.14.4/8.13.1/NCO v10.0 AVin) with ESMTP id p899b5ER006108; Fri, 9 Sep 2011 03:37:05 -0600 From: Stefan Hajnoczi To: Date: Fri, 9 Sep 2011 10:37:01 +0100 Message-Id: <1315561022-25386-2-git-send-email-stefanha@linux.vnet.ibm.com> X-Mailer: git-send-email 1.7.5.4 In-Reply-To: <1315561022-25386-1-git-send-email-stefanha@linux.vnet.ibm.com> References: <1315561022-25386-1-git-send-email-stefanha@linux.vnet.ibm.com> X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.6, seldom 2.4 (older, 4) X-Received-From: 194.196.100.167 Cc: Jan Kiszka , Stefan Hajnoczi Subject: [Qemu-devel] [PATCH 1/2] trace: portable simple trace backend using glib X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Sender: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Convert the simple trace backend to glib so that it works under Windows. We cannot use pthread directly but glib provides portable abstractions. Also use glib atomics instead of newish gcc builtins which may not be supported on Windows toolchains. Signed-off-by: Stefan Hajnoczi --- trace/simple.c | 56 ++++++++++++++++++++++++++------------------------------ 1 files changed, 26 insertions(+), 30 deletions(-) diff --git a/trace/simple.c b/trace/simple.c index a609368..92c315a 100644 --- a/trace/simple.c +++ b/trace/simple.c @@ -12,8 +12,6 @@ #include #include #include -#include -#include #include "qemu-timer.h" #include "trace.h" #include "trace/control.h" @@ -54,9 +52,9 @@ enum { * Trace records are written out by a dedicated thread. The thread waits for * records to become available, writes them out, and then waits again. */ -static pthread_mutex_t trace_lock = PTHREAD_MUTEX_INITIALIZER; -static pthread_cond_t trace_available_cond = PTHREAD_COND_INITIALIZER; -static pthread_cond_t trace_empty_cond = PTHREAD_COND_INITIALIZER; +static GStaticMutex trace_lock = G_STATIC_MUTEX_INIT; +static GCond *trace_available_cond; +static GCond *trace_empty_cond; static bool trace_available; static bool trace_writeout_enabled; @@ -93,29 +91,30 @@ static bool get_trace_record(unsigned int idx, TraceRecord *record) */ static void flush_trace_file(bool wait) { - pthread_mutex_lock(&trace_lock); + g_static_mutex_lock(&trace_lock); trace_available = true; - pthread_cond_signal(&trace_available_cond); + g_cond_signal(trace_available_cond); if (wait) { - pthread_cond_wait(&trace_empty_cond, &trace_lock); + g_cond_wait(trace_empty_cond, g_static_mutex_get_mutex(&trace_lock)); } - pthread_mutex_unlock(&trace_lock); + g_static_mutex_unlock(&trace_lock); } static void wait_for_trace_records_available(void) { - pthread_mutex_lock(&trace_lock); + g_static_mutex_lock(&trace_lock); while (!(trace_available && trace_writeout_enabled)) { - pthread_cond_signal(&trace_empty_cond); - pthread_cond_wait(&trace_available_cond, &trace_lock); + g_cond_signal(trace_empty_cond); + g_cond_wait(trace_available_cond, + g_static_mutex_get_mutex(&trace_lock)); } trace_available = false; - pthread_mutex_unlock(&trace_lock); + g_static_mutex_unlock(&trace_lock); } -static void *writeout_thread(void *opaque) +static gpointer writeout_thread(gpointer opaque) { TraceRecord record; unsigned int writeout_idx = 0; @@ -159,7 +158,7 @@ static void trace(TraceEventID event, uint64_t x1, uint64_t x2, uint64_t x3, timestamp = get_clock(); - idx = __sync_fetch_and_add(&trace_idx, 1) % TRACE_BUF_LEN; + idx = g_atomic_int_exchange_and_add((gint *)&trace_idx, 1) % TRACE_BUF_LEN; trace_buf[idx] = (TraceRecord){ .event = event, .timestamp_ns = timestamp, @@ -333,26 +332,23 @@ bool trace_event_set_state(const char *name, bool state) bool trace_backend_init(const char *events, const char *file) { - pthread_t thread; - pthread_attr_t attr; - sigset_t set, oldset; - int ret; + GThread *thread; - pthread_attr_init(&attr); - pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_DETACHED); + if (!g_thread_supported()) { + g_thread_init(NULL); + } - sigfillset(&set); - pthread_sigmask(SIG_SETMASK, &set, &oldset); - ret = pthread_create(&thread, &attr, writeout_thread, NULL); - pthread_sigmask(SIG_SETMASK, &oldset, NULL); + trace_available_cond = g_cond_new(); + trace_empty_cond = g_cond_new(); - if (ret != 0) { + thread = g_thread_create(writeout_thread, NULL, FALSE, NULL); + if (!thread) { fprintf(stderr, "warning: unable to initialize simple trace backend\n"); - } else { - atexit(st_flush_trace_buffer); - trace_backend_init_events(events); - st_set_trace_file(file); + return false; } + atexit(st_flush_trace_buffer); + trace_backend_init_events(events); + st_set_trace_file(file); return true; }