From nobody Mon Feb 9 19:06:20 2026 Delivered-To: importer@patchew.org Authentication-Results: mx.zohomail.com; dkim=fail; spf=pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org; dmarc=fail(p=none dis=none) header.from=redhat.com Return-Path: Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) by mx.zohomail.com with SMTPS id 1629107508608833.8452766777153; Mon, 16 Aug 2021 02:51:48 -0700 (PDT) Received: from localhost ([::1]:50012 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1mFZHX-0004so-Qy for importer@patchew.org; Mon, 16 Aug 2021 05:51:47 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:58650) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1mFZDv-00061K-TA for qemu-devel@nongnu.org; Mon, 16 Aug 2021 05:48:03 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]:23657) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1mFZDu-00058B-6y for qemu-devel@nongnu.org; Mon, 16 Aug 2021 05:48:03 -0400 Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-442-jso6mmS3MGW-1fwu-rOW4Q-1; Mon, 16 Aug 2021 05:48:00 -0400 Received: from smtp.corp.redhat.com (int-mx08.intmail.prod.int.phx2.redhat.com [10.5.11.23]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 740D592502; Mon, 16 Aug 2021 09:47:59 +0000 (UTC) Received: from t480s.redhat.com (unknown [10.39.192.85]) by smtp.corp.redhat.com (Postfix) with ESMTP id 1A9B019C44; Mon, 16 Aug 2021 09:47:56 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1629107281; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=E2hPa3OeU2VShLBIWGRBI4Pl+wvAn0MdoP0MtSPhYqc=; b=KihH8dOaJGtVDHLHLX2S0YYHy5Yr+U/6oyQ/65xfPlBF5Wh4IbCrxAMXk+hCxinwlCgexl S2yiSRNA9JS1ZfC5nE1d/HD5c4X8Q/BUa0Q6duQ1rI5akDNvcQr7Y3CqVtHaE/mMD2KltH f1MibeTdeweh9rzyHcPe4xO8pMHcH8M= X-MC-Unique: jso6mmS3MGW-1fwu-rOW4Q-1 From: David Hildenbrand To: qemu-devel@nongnu.org Subject: [PATCH v3 3/7] util/oslib-posix: Introduce and use MemsetContext for touch_all_pages() Date: Mon, 16 Aug 2021 11:47:35 +0200 Message-Id: <20210816094739.21970-4-david@redhat.com> In-Reply-To: <20210816094739.21970-1-david@redhat.com> References: <20210816094739.21970-1-david@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.84 on 10.5.11.23 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=david@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable Received-SPF: pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) client-ip=209.51.188.17; envelope-from=qemu-devel-bounces+importer=patchew.org@nongnu.org; helo=lists.gnu.org; Received-SPF: pass client-ip=170.10.133.124; envelope-from=david@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -34 X-Spam_score: -3.5 X-Spam_bar: --- X-Spam_report: (-3.5 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.699, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_LOW=-0.7, RCVD_IN_MSPIKE_H2=-0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Pankaj Gupta , =?UTF-8?q?Daniel=20P=20=2E=20Berrang=C3=A9?= , Eduardo Habkost , "Michael S. Tsirkin" , David Hildenbrand , "Dr . David Alan Gilbert" , Igor Mammedov , Paolo Bonzini Errors-To: qemu-devel-bounces+importer=patchew.org@nongnu.org Sender: "Qemu-devel" X-ZohoMail-DKIM: fail (Header signature does not verify) X-ZM-MESSAGEID: 1629107510746100001 Let's minimize the number of global variables to prepare for os_mem_prealloc() getting called concurrently and make the code a bit easier to read. The only consumer that really needs a global variable is the sigbus handler, which will require protection via a mutex in the future either way as we cannot concurrently mess with the SIGBUS handler. Reviewed-by: Daniel P. Berrang=C3=A9 Signed-off-by: David Hildenbrand --- util/oslib-posix.c | 73 +++++++++++++++++++++++++++++----------------- 1 file changed, 47 insertions(+), 26 deletions(-) diff --git a/util/oslib-posix.c b/util/oslib-posix.c index cb89e07770..cf2ead54ad 100644 --- a/util/oslib-posix.c +++ b/util/oslib-posix.c @@ -73,21 +73,30 @@ =20 #define MAX_MEM_PREALLOC_THREAD_COUNT 16 =20 +struct MemsetThread; + +typedef struct MemsetContext { + bool all_threads_created; + bool any_thread_failed; + struct MemsetThread *threads; + int num_threads; +} MemsetContext; + struct MemsetThread { char *addr; size_t numpages; size_t hpagesize; QemuThread pgthread; sigjmp_buf env; + MemsetContext *context; }; typedef struct MemsetThread MemsetThread; =20 -static MemsetThread *memset_thread; -static int memset_num_threads; +/* used by sigbus_handler() */ +static MemsetContext *sigbus_memset_context; =20 static QemuMutex page_mutex; static QemuCond page_cond; -static bool threads_created_flag; =20 int qemu_get_thread_id(void) { @@ -438,10 +447,13 @@ const char *qemu_get_exec_dir(void) static void sigbus_handler(int signal) { int i; - if (memset_thread) { - for (i =3D 0; i < memset_num_threads; i++) { - if (qemu_thread_is_self(&memset_thread[i].pgthread)) { - siglongjmp(memset_thread[i].env, 1); + + if (sigbus_memset_context) { + for (i =3D 0; i < sigbus_memset_context->num_threads; i++) { + MemsetThread *thread =3D &sigbus_memset_context->threads[i]; + + if (qemu_thread_is_self(&thread->pgthread)) { + siglongjmp(thread->env, 1); } } } @@ -459,7 +471,7 @@ static void *do_touch_pages(void *arg) * clearing until all threads have been created. */ qemu_mutex_lock(&page_mutex); - while(!threads_created_flag){ + while (!memset_args->context->all_threads_created) { qemu_cond_wait(&page_cond, &page_mutex); } qemu_mutex_unlock(&page_mutex); @@ -502,7 +514,7 @@ static void *do_madv_populate_write_pages(void *arg) =20 /* See do_touch_pages(). */ qemu_mutex_lock(&page_mutex); - while (!threads_created_flag) { + while (!memset_args->context->all_threads_created) { qemu_cond_wait(&page_cond, &page_mutex); } qemu_mutex_unlock(&page_mutex); @@ -529,6 +541,9 @@ static int touch_all_pages(char *area, size_t hpagesize= , size_t numpages, int smp_cpus, bool use_madv_populate_write) { static gsize initialized =3D 0; + MemsetContext context =3D { + .num_threads =3D get_memset_num_threads(smp_cpus), + }; size_t numpages_per_thread, leftover; void *(*touch_fn)(void *); int ret =3D 0, i =3D 0; @@ -546,35 +561,41 @@ static int touch_all_pages(char *area, size_t hpagesi= ze, size_t numpages, touch_fn =3D do_touch_pages; } =20 - threads_created_flag =3D false; - memset_num_threads =3D get_memset_num_threads(smp_cpus); - memset_thread =3D g_new0(MemsetThread, memset_num_threads); - numpages_per_thread =3D numpages / memset_num_threads; - leftover =3D numpages % memset_num_threads; - for (i =3D 0; i < memset_num_threads; i++) { - memset_thread[i].addr =3D addr; - memset_thread[i].numpages =3D numpages_per_thread + (i < leftover); - memset_thread[i].hpagesize =3D hpagesize; - qemu_thread_create(&memset_thread[i].pgthread, "touch_pages", - touch_fn, &memset_thread[i], + context.threads =3D g_new0(MemsetThread, context.num_threads); + numpages_per_thread =3D numpages / context.num_threads; + leftover =3D numpages % context.num_threads; + for (i =3D 0; i < context.num_threads; i++) { + context.threads[i].addr =3D addr; + context.threads[i].numpages =3D numpages_per_thread + (i < leftove= r); + context.threads[i].hpagesize =3D hpagesize; + context.threads[i].context =3D &context; + qemu_thread_create(&context.threads[i].pgthread, "touch_pages", + touch_fn, &context.threads[i], QEMU_THREAD_JOINABLE); - addr +=3D memset_thread[i].numpages * hpagesize; + addr +=3D context.threads[i].numpages * hpagesize; + } + + if (!use_madv_populate_write) { + sigbus_memset_context =3D &context; } =20 qemu_mutex_lock(&page_mutex); - threads_created_flag =3D true; + context.all_threads_created =3D true; qemu_cond_broadcast(&page_cond); qemu_mutex_unlock(&page_mutex); =20 - for (i =3D 0; i < memset_num_threads; i++) { - int tmp =3D (uintptr_t)qemu_thread_join(&memset_thread[i].pgthread= ); + for (i =3D 0; i < context.num_threads; i++) { + int tmp =3D (uintptr_t)qemu_thread_join(&context.threads[i].pgthre= ad); =20 if (tmp) { ret =3D tmp; } } - g_free(memset_thread); - memset_thread =3D NULL; + + if (!use_madv_populate_write) { + sigbus_memset_context =3D NULL; + } + g_free(context.threads); =20 return ret; } --=20 2.31.1