From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mails.dpdk.org (mails.dpdk.org [217.70.189.124]) by inbox.dpdk.org (Postfix) with ESMTP id 0A62545C59 for ; Sat, 2 Nov 2024 12:32:45 +0100 (CET) Received: from mails.dpdk.org (localhost [127.0.0.1]) by mails.dpdk.org (Postfix) with ESMTP id DF66A40649; Sat, 2 Nov 2024 12:32:44 +0100 (CET) Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) by mails.dpdk.org (Postfix) with ESMTP id CE7EF40649 for ; Sat, 2 Nov 2024 12:32:43 +0100 (CET) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1730547163; 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=7XoeoehRca0I0J/wbT2NzhrdpcE8Cv4Xgh3/CUcSFho=; b=dhC42ghAl5Z2/2JWL0An6Ya9VEVIIua0TB5vI+UrL0SkVt/uN/qHTtyYPtSJf5WjmR4Gt3 2H1mS64/ttx0MHIo1/8tK+1Ji5BJo5TOhZja5FVDDjNSDibHgtdXcMgEXtNlO7CEiVKZT/ LppHZL2lPZQrTdBGxk9MqJ7AIIBXbN0= Received: from mx-prod-mc-04.mail-002.prod.us-west-2.aws.redhat.com (ec2-54-186-198-63.us-west-2.compute.amazonaws.com [54.186.198.63]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-449-SkTC_35ePcOjiZ9ujCVbkw-1; Sat, 02 Nov 2024 07:32:40 -0400 X-MC-Unique: SkTC_35ePcOjiZ9ujCVbkw-1 Received: from mx-prod-int-05.mail-002.prod.us-west-2.aws.redhat.com (mx-prod-int-05.mail-002.prod.us-west-2.aws.redhat.com [10.30.177.17]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mx-prod-mc-04.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id 6E4C319560A2; Sat, 2 Nov 2024 11:32:38 +0000 (UTC) Received: from dmarchan.redhat.com (unknown [10.45.224.57]) by mx-prod-int-05.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTP id E50AC1956052; Sat, 2 Nov 2024 11:32:35 +0000 (UTC) From: David Marchand To: dev@dpdk.org Cc: thomas@monjalon.net, stephen@networkplumber.org, luca.boccassi@gmail.com, stable@dpdk.org, Tyler Retzlaff Subject: [PATCH v2] eal/unix: optimize thread creation with glibc Date: Sat, 2 Nov 2024 12:32:32 +0100 Message-ID: <20241102113232.2333703-1-david.marchand@redhat.com> In-Reply-To: <20241102100839.2325651-1-david.marchand@redhat.com> References: <20241102100839.2325651-1-david.marchand@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.0 on 10.30.177.17 X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Transfer-Encoding: 8bit Content-Type: text/plain; charset="US-ASCII"; x-default=true X-BeenThere: stable@dpdk.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: patches for DPDK stable branches List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: stable-bounces@dpdk.org Setting the cpu affinity of the child thread from the parent thread is racy when using pthread_setaffinity_np, as the child thread may start running and initialize before affinity is set. On the other hand, setting the cpu affinity from the child thread itself may fail, so the parent thread waits for the child thread to report whether this call succeeded. This synchronisation point resulted in a significant slow down of rte_thread_create() (as seen in the lcores_autotest unit tests, in OBS for some ARM systems). Another option for setting cpu affinity is to use the not portable pthread_attr_setaffinity_np, but it is not available with musl. Assume availability by relying on __USE_GNU that is set with glibc. Fixes: b28c6196b132 ("eal/unix: fix thread creation") Cc: stable@dpdk.org Signed-off-by: David Marchand --- Changes since v1: - fixed build with FreeBSD, --- lib/eal/unix/rte_thread.c | 25 +++++++++++++++++++++++++ 1 file changed, 25 insertions(+) diff --git a/lib/eal/unix/rte_thread.c b/lib/eal/unix/rte_thread.c index 1b4c73f58e..03c4164059 100644 --- a/lib/eal/unix/rte_thread.c +++ b/lib/eal/unix/rte_thread.c @@ -19,6 +19,7 @@ struct eal_tls_key { pthread_key_t thread_index; }; +#ifndef __USE_GNU struct thread_start_context { rte_thread_func thread_func; void *thread_args; @@ -28,6 +29,7 @@ struct thread_start_context { int wrapper_ret; bool wrapper_done; }; +#endif static int thread_map_priority_to_os_value(enum rte_thread_priority eal_pri, int *os_pri, @@ -88,6 +90,7 @@ thread_map_os_priority_to_eal_priority(int policy, int os_pri, return 0; } +#ifndef __USE_GNU static void * thread_start_wrapper(void *arg) { @@ -113,6 +116,7 @@ thread_start_wrapper(void *arg) return (void *)(uintptr_t)thread_func(thread_args); } +#endif int rte_thread_create(rte_thread_t *thread_id, @@ -126,6 +130,7 @@ rte_thread_create(rte_thread_t *thread_id, .sched_priority = 0, }; int policy = SCHED_OTHER; +#ifndef __USE_GNU struct thread_start_context ctx = { .thread_func = thread_func, .thread_args = args, @@ -134,6 +139,7 @@ rte_thread_create(rte_thread_t *thread_id, .wrapper_mutex = PTHREAD_MUTEX_INITIALIZER, .wrapper_cond = PTHREAD_COND_INITIALIZER, }; +#endif if (thread_attr != NULL) { ret = pthread_attr_init(&attr); @@ -144,6 +150,16 @@ rte_thread_create(rte_thread_t *thread_id, attrp = &attr; +#ifdef __USE_GNU + if (CPU_COUNT(&thread_attr->cpuset) > 0) { + ret = pthread_attr_setaffinity_np(attrp, sizeof(thread_attr->cpuset), + &thread_attr->cpuset); + if (ret != 0) { + EAL_LOG(DEBUG, "pthread_attr_setaffinity_np failed"); + goto cleanup; + } + } +#endif /* * Set the inherit scheduler parameter to explicit, * otherwise the priority attribute is ignored. @@ -178,6 +194,14 @@ rte_thread_create(rte_thread_t *thread_id, } } +#ifdef __USE_GNU + ret = pthread_create((pthread_t *)&thread_id->opaque_id, attrp, + (void *)(void *)thread_func, args); + if (ret != 0) { + EAL_LOG(DEBUG, "pthread_create failed"); + goto cleanup; + } +#else /* !__USE_GNU */ ret = pthread_create((pthread_t *)&thread_id->opaque_id, attrp, thread_start_wrapper, &ctx); if (ret != 0) { @@ -193,6 +217,7 @@ rte_thread_create(rte_thread_t *thread_id, if (ret != 0) rte_thread_join(*thread_id, NULL); +#endif /* __USE_GNU */ cleanup: if (attrp != NULL) -- 2.46.2