From patchwork Thu Jul 7 11:37:25 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Peter Lieven X-Patchwork-Id: 645834 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from lists.gnu.org (lists.gnu.org [IPv6:2001:4830:134:3::11]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id 3rlbJ26jzVz9sBl for ; Thu, 7 Jul 2016 21:39:30 +1000 (AEST) Received: from localhost ([::1]:39006 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1bL7eS-00021v-IJ for incoming@patchwork.ozlabs.org; Thu, 07 Jul 2016 07:39:28 -0400 Received: from eggs.gnu.org ([2001:4830:134:3::10]:33631) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1bL7cw-0000uA-2C for qemu-devel@nongnu.org; Thu, 07 Jul 2016 07:37:57 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1bL7ct-0005Lo-Vi for qemu-devel@nongnu.org; Thu, 07 Jul 2016 07:37:53 -0400 Received: from mx-v6.kamp.de ([2a02:248:0:51::16]:51973 helo=mx01.kamp.de) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1bL7ct-0005Le-M6 for qemu-devel@nongnu.org; Thu, 07 Jul 2016 07:37:51 -0400 Received: (qmail 8431 invoked by uid 89); 7 Jul 2016 11:37:50 -0000 Received: from [195.62.97.28] by client-16-kamp (envelope-from , uid 89) with qmail-scanner-2010/03/19-MF (clamdscan: 0.99.2/21858. hbedv: 8.3.40.44/7.12.99.34. avast: 1.2.2/16070700. spamassassin: 3.4.1. 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Processed in 0.278405 secs); 07 Jul 2016 11:37:50 -0000 Received: from smtp.kamp.de (HELO submission.kamp.de) ([195.62.97.28]) by mx01.kamp.de with ESMTPS (DHE-RSA-AES256-GCM-SHA384 encrypted); 7 Jul 2016 11:37:47 -0000 X-GL_Whitelist: yes Received: (qmail 14730 invoked from network); 7 Jul 2016 11:37:37 -0000 Received: from lieven-pc.kamp-intra.net (HELO lieven-pc) (relay@kamp.de@::ffff:172.21.12.60) by submission.kamp.de with ESMTPS (DHE-RSA-AES256-GCM-SHA384 encrypted) ESMTPA; 7 Jul 2016 11:37:37 -0000 Received: by lieven-pc (Postfix, from userid 1000) id CBD6B208D5; Thu, 7 Jul 2016 13:37:36 +0200 (CEST) From: Peter Lieven To: qemu-devel@nongnu.org Date: Thu, 7 Jul 2016 13:37:25 +0200 Message-Id: <1467891446-22267-6-git-send-email-pl@kamp.de> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1467891446-22267-1-git-send-email-pl@kamp.de> References: <1467891446-22267-1-git-send-email-pl@kamp.de> X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] X-Received-From: 2a02:248:0:51::16 Subject: [Qemu-devel] [PATCH V3 5/6] oslib-posix: add a configure switch to debug stack usage X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: kwolf@redhat.com, peter.maydell@linaro.org, mst@redhat.com, armbru@redhat.com, Peter Lieven , dgilbert@redhat.com, mreitz@redhat.com, pbonzini@redhat.com, rth@twiddle.net Errors-To: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Sender: "Qemu-devel" this adds a knob to track the maximum stack usage of stacks created by qemu_alloc_stack. Signed-off-by: Peter Lieven --- configure | 19 +++++++++++++++++++ util/oslib-posix.c | 37 +++++++++++++++++++++++++++++++++++++ 2 files changed, 56 insertions(+) diff --git a/configure b/configure index 93e4c95..d13ad1d 100755 --- a/configure +++ b/configure @@ -296,6 +296,7 @@ libiscsi="" libnfs="" coroutine="" coroutine_pool="" +debug_stack_usage="no" seccomp="" glusterfs="" glusterfs_xlator_opt="no" @@ -1004,6 +1005,8 @@ for opt do ;; --enable-coroutine-pool) coroutine_pool="yes" ;; + --enable-debug-stack-usage) debug_stack_usage="yes" + ;; --disable-docs) docs="no" ;; --enable-docs) docs="yes" @@ -4307,6 +4310,17 @@ if test "$coroutine" = "gthread" -a "$coroutine_pool" = "yes"; then error_exit "'gthread' coroutine backend does not support pool (use --disable-coroutine-pool)" fi +if test "$debug_stack_usage" = "yes"; then + if test "$cpu" = "ia64" -o "$cpu" = "hppa"; then + error_exit "stack usage debugging is not supported for $cpu" + fi + if test "$coroutine_pool" = "yes"; then + echo "WARN: disabling coroutine pool for stack usage debugging" + coroutine_pool=no + fi +fi + + ########################################## # check if we have open_by_handle_at @@ -4884,6 +4898,7 @@ echo "QGA MSI support $guest_agent_msi" echo "seccomp support $seccomp" echo "coroutine backend $coroutine" echo "coroutine pool $coroutine_pool" +echo "debug stack usage $debug_stack_usage" echo "GlusterFS support $glusterfs" echo "Archipelago support $archipelago" echo "gcov $gcov_tool" @@ -5354,6 +5369,10 @@ else echo "CONFIG_COROUTINE_POOL=0" >> $config_host_mak fi +if test "$debug_stack_usage" = "yes" ; then + echo "CONFIG_DEBUG_STACK_USAGE=y" >> $config_host_mak +fi + if test "$open_by_handle_at" = "yes" ; then echo "CONFIG_OPEN_BY_HANDLE=y" >> $config_host_mak fi diff --git a/util/oslib-posix.c b/util/oslib-posix.c index 1ce35ef..4298465 100644 --- a/util/oslib-posix.c +++ b/util/oslib-posix.c @@ -50,6 +50,10 @@ #include +#ifdef CONFIG_DEBUG_STACK_USAGE +#include "qemu/error-report.h" +#endif + int qemu_get_thread_id(void) { #if defined(__linux__) @@ -501,6 +505,9 @@ pid_t qemu_fork(Error **errp) void *qemu_alloc_stack(size_t sz) { void *ptr, *guardpage; +#ifdef CONFIG_DEBUG_STACK_USAGE + void *ptr2; +#endif size_t pagesz = getpagesize(); /* avoid stacks smaller than _SC_THREAD_STACK_MIN */ @@ -528,11 +535,41 @@ void *qemu_alloc_stack(size_t sz) abort(); } +#ifdef CONFIG_DEBUG_STACK_USAGE + for (ptr2 = ptr + pagesz; ptr2 < ptr + sz; ptr2 += sizeof(uint32_t)) { + *(uint32_t *)ptr2 = 0xdeadbeaf; + } +#endif + return ptr; } +#ifdef CONFIG_DEBUG_STACK_USAGE +static __thread unsigned int max_stack_usage; +#endif + void qemu_free_stack(void *stack, size_t sz) { +#ifdef CONFIG_DEBUG_STACK_USAGE + unsigned int usage; + void *ptr; +#endif sz = MAX(sz, sysconf(_SC_THREAD_STACK_MIN)); + +#ifdef CONFIG_DEBUG_STACK_USAGE + for (ptr = stack + getpagesize(); ptr < stack + sz; + ptr += sizeof(uint32_t)) { + if (*(uint32_t *)ptr != 0xdeadbeaf) { + break; + } + } + usage = sz - (uintptr_t) (ptr - stack); + if (usage > max_stack_usage) { + error_report("thread %d max stack usage increased from %u to %u", + qemu_get_thread_id(), max_stack_usage, usage); + max_stack_usage = usage; + } +#endif + munmap(stack, sz); }