From patchwork Tue Feb 25 11:00:18 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Uladzislau Rezki X-Patchwork-Id: 13989795 Received: from mail-lf1-f45.google.com (mail-lf1-f45.google.com [209.85.167.45]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id C8C22267B97; Tue, 25 Feb 2025 11:00:24 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.167.45 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1740481226; cv=none; b=JOjzBCx1rburyzwlqWdM7T3dhFGmbERfTUxTQw0+bOZH3Cqi9aBdHT8NFm+YeDIRzOji+9pQjCSDXRQKD4nO4nW0t36kExBAet5nuRbGeCJkzAiqf7wAHwI5jedFFZjGGbi1g7ze1r8iCCkhub0Ve6huy4WWPbVSGOO5jjmUqj8= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1740481226; c=relaxed/simple; bh=3QC7bLLQ/zkEb/zgxj1H5xIc9uVr/+bRhetdiLgORIM=; h=From:To:Cc:Subject:Date:Message-Id:MIME-Version; b=qy2VqDNx1J40uNgSTiH9OSgIh1UQC3U6Sp2JMsLWy4wiMH/vbiYUSndVERq0XmXpsOyMaOzWbC6X8SLaV44LhiyMNdsdCRHwUZ+JCGNAMlrEL7uF/DMB6DAMWGHsd0KFOtB3zI0rp+bG2L28F3fUk2gcLSxJ/SiG51GdVd5U8WQ= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com; spf=pass smtp.mailfrom=gmail.com; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b=bMmSyc37; arc=none smtp.client-ip=209.85.167.45 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=gmail.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="bMmSyc37" Received: by mail-lf1-f45.google.com with SMTP id 2adb3069b0e04-5461f2ca386so4668153e87.1; Tue, 25 Feb 2025 03:00:24 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1740481223; x=1741086023; darn=vger.kernel.org; h=content-transfer-encoding:mime-version:message-id:date:subject:cc :to:from:from:to:cc:subject:date:message-id:reply-to; bh=miA+E2wD4Pd4SV+NIcjk6rwZpf9OynLUKJ339stxcis=; b=bMmSyc378ScpxzmJJBFTAr/qMJQBysla/daIhnk5rdmzb2GAXDBx3RN3pz6O1Wnmli kqYS6h2Sdda2aYGjQMtsFFV2rSf/Zzw7BghirbPQp8O89QFq/QSohcwsoGk1rB3Djmrv hGoJCl1g56Mtuqy1nYsoeP3C74KfP+Ammml4H2+YAyWJxpilG+1xHWS6qpqV3iWK2q7B nDCU9U0+NcKZ0D0WpoP69Pz2A5YRfJF24EYQA50VrVB4cXzt7TBCc5bPAHl89LC1kE5B RTb5XnGzxf5jDGdrQdSLnqmhjbOyj1eGPb+Xmbj0KqrmDczQLiGMMP9lfgEz6J9OVC35 74wg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1740481223; x=1741086023; h=content-transfer-encoding:mime-version:message-id:date:subject:cc :to:from:x-gm-message-state:from:to:cc:subject:date:message-id :reply-to; bh=miA+E2wD4Pd4SV+NIcjk6rwZpf9OynLUKJ339stxcis=; b=IOcZXxbLLbytL2R/jkMS1OOxNlI4JMjV7dv5ugDTNep0yTmvWjnvjZzxnccRa8lF6o itAPxQAK9u3ttgEdfwaDBoMEn2OuJWpA/VVu9uuYsiivnvF800+Q/bI029rTyDapNQpb y1v4oraoTxxh66TKe4hzhDNSPVAeuSJLDyTD1gGrdI0YcBzxheNyVYRTqaHz/wf0CxQ1 57P2c1Z2Idy9YHtN+o55AITv4BbVYCj9hVCMNHdmyL5qGebqJsY46dHJQtwgGJalwy5J oAZ/7NGkjYnVkPLYTjVojdure/IsqkZtFZ8RDHypdDPYfeMHKQnzMBUft3h79Vnz2rS/ wIxg== X-Forwarded-Encrypted: i=1; AJvYcCXi+qC8HWA3DzZdBNxk5lRuIUG0YqOvTo6zKsMTahAnHny7+eY57Go7SlrPkF6ss2NNTOf5zRE6cj9xUhY=@vger.kernel.org X-Gm-Message-State: AOJu0YwF7Ux96InybvkGDCh853VgHqJMNliSYsdEZO9OL58gPYaF6Jf8 mWU2vb6ggn1DCZZZjSwoncvvaTws9j2xOoXZtJuC0TbSK+pnqt0d X-Gm-Gg: ASbGncv/mLaadHav0/03SGDVf6ht33wRcQJ4ebfRgGuQQOnaINzZCxiooI53zIx9j5L BbL3lm4wIpn32M5N0WA9qhgWlo9OFIJuijEWCQFVwihPNnO3+MnWSf9GyyRfW5wD3X8TSxWC6i7 8r8YOcN4IhnwoJ0RsPxn9EBrGylnCkZgoOrL2UetIPPHIOpQm/j6KZFvxnS/uvfRUmAIKwC4RfK XCnwx+Ff38k7FIVce5zPZDf7p56hgxNLE+1GKgIuLR0lWXECZX1QizenUo60j9dQFYxhT65ywsg mP8rYk2oXPU2I3ohu08ZIw== X-Google-Smtp-Source: AGHT+IETbAXIoIWzB9fO+htnlh5GeNXoYelbVkB32w3oybvIUeQtcTfGyBpIkXj6AQXbtlpZtX8MDQ== X-Received: by 2002:a05:6512:3b2b:b0:545:a1a:5576 with SMTP id 2adb3069b0e04-5483914012cmr6514678e87.22.1740481222380; Tue, 25 Feb 2025 03:00:22 -0800 (PST) Received: from pc638.lan ([2001:9b1:d5a0:a500:2d8:61ff:fec9:d743]) by smtp.gmail.com with ESMTPSA id 2adb3069b0e04-548514b9886sm143850e87.71.2025.02.25.03.00.21 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 25 Feb 2025 03:00:21 -0800 (PST) From: "Uladzislau Rezki (Sony)" To: "Paul E . McKenney" , Boqun Feng Cc: RCU , LKML , Frederic Weisbecker , Cheung Wall , Neeraj upadhyay , Joel Fernandes , Uladzislau Rezki , Oleksiy Avramchenko Subject: [PATCH v3 1/3] rcutorture: Allow a negative value for nfakewriters Date: Tue, 25 Feb 2025 12:00:18 +0100 Message-Id: <20250225110020.59221-1-urezki@gmail.com> X-Mailer: git-send-email 2.39.5 Precedence: bulk X-Mailing-List: rcu@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Currently "nfakewriters" parameter can be set to any value but there is no possibility to adjust it automatically based on how many CPUs a system has where a test is run on. To address this, if the "nfakewriters" is set to negative it will be adjusted to num_online_cpus() during torture initialization. Reviewed-by: Paul E. McKenney Signed-off-by: Uladzislau Rezki (Sony) --- kernel/rcu/rcutorture.c | 22 ++++++++++++++++------ 1 file changed, 16 insertions(+), 6 deletions(-) diff --git a/kernel/rcu/rcutorture.c b/kernel/rcu/rcutorture.c index d98b3bd6d91f..f376262532ce 100644 --- a/kernel/rcu/rcutorture.c +++ b/kernel/rcu/rcutorture.c @@ -148,6 +148,7 @@ MODULE_PARM_DESC(torture_type, "Type of RCU to torture (rcu, srcu, ...)"); static int nrealnocbers; static int nrealreaders; +static int nrealfakewriters; static struct task_struct *writer_task; static struct task_struct **fakewriter_tasks; static struct task_struct **reader_tasks; @@ -1763,7 +1764,7 @@ rcu_torture_fakewriter(void *arg) do { torture_hrtimeout_jiffies(torture_random(&rand) % 10, &rand); if (cur_ops->cb_barrier != NULL && - torture_random(&rand) % (nfakewriters * 8) == 0) { + torture_random(&rand) % (nrealfakewriters * 8) == 0) { cur_ops->cb_barrier(); } else { switch (synctype[torture_random(&rand) % nsynctypes]) { @@ -2568,7 +2569,7 @@ rcu_torture_print_module_parms(struct rcu_torture_ops *cur_ops, const char *tag) "nocbs_nthreads=%d nocbs_toggle=%d " "test_nmis=%d " "preempt_duration=%d preempt_interval=%d\n", - torture_type, tag, nrealreaders, nfakewriters, + torture_type, tag, nrealreaders, nrealfakewriters, stat_interval, verbose, test_no_idle_hz, shuffle_interval, stutter, irqreader, fqs_duration, fqs_holdoff, fqs_stutter, test_boost, cur_ops->can_boost, @@ -3644,7 +3645,7 @@ rcu_torture_cleanup(void) rcu_torture_reader_mbchk = NULL; if (fakewriter_tasks) { - for (i = 0; i < nfakewriters; i++) + for (i = 0; i < nrealfakewriters; i++) torture_stop_kthread(rcu_torture_fakewriter, fakewriter_tasks[i]); kfree(fakewriter_tasks); @@ -4066,6 +4067,14 @@ rcu_torture_init(void) rcu_torture_init_srcu_lockdep(); + if (nfakewriters >= 0) { + nrealfakewriters = nfakewriters; + } else { + nrealfakewriters = num_online_cpus() - 2 - nfakewriters; + if (nrealfakewriters <= 0) + nrealfakewriters = 1; + } + if (nreaders >= 0) { nrealreaders = nreaders; } else { @@ -4122,8 +4131,9 @@ rcu_torture_init(void) writer_task); if (torture_init_error(firsterr)) goto unwind; - if (nfakewriters > 0) { - fakewriter_tasks = kcalloc(nfakewriters, + + if (nrealfakewriters > 0) { + fakewriter_tasks = kcalloc(nrealfakewriters, sizeof(fakewriter_tasks[0]), GFP_KERNEL); if (fakewriter_tasks == NULL) { @@ -4132,7 +4142,7 @@ rcu_torture_init(void) goto unwind; } } - for (i = 0; i < nfakewriters; i++) { + for (i = 0; i < nrealfakewriters; i++) { firsterr = torture_create_kthread(rcu_torture_fakewriter, NULL, fakewriter_tasks[i]); if (torture_init_error(firsterr)) From patchwork Tue Feb 25 11:00:19 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Uladzislau Rezki X-Patchwork-Id: 13989796 Received: from mail-lf1-f45.google.com (mail-lf1-f45.google.com [209.85.167.45]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 9B2AC267F4D; Tue, 25 Feb 2025 11:00:25 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.167.45 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1740481227; cv=none; b=hj58KgwCFkyq0GjSaZt4wNqWvn/tAX/9Fd+OXkPJy0QXyFnpYUtNiqAC/EonUxDIOrLX24neO+DrUL/+33PD39jpP+6zOnGyHZMb9We3Iyf3dqRJlhi+uJsY3to4VmI9jDxUGDkb4ItvbWmRn/M07scC56fK+zazUi3E7SCgOTA= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1740481227; c=relaxed/simple; bh=sCuflgFUh/45tShowZi3ebLKyBuj3+UPfLcwZ/CRsbA=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=cLza+1tTOiYhpChYNx7P7jTc31Tre65Uw3yZMWszrPQJSob0hJLNIvbxoOzRYOQDMlepiLLyL4NVLlqtaECu/XNqmmZkosPqWBcuhbrEMhPlmwXAuV+tj0CBSvi8ITFdkswjMteme5W5yBKPfchpt9dg9MrkvtAk9CG8ii982dc= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com; spf=pass smtp.mailfrom=gmail.com; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b=Dbj0C96D; arc=none smtp.client-ip=209.85.167.45 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=gmail.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="Dbj0C96D" Received: by mail-lf1-f45.google.com with SMTP id 2adb3069b0e04-5461dab4bfdso6525263e87.3; Tue, 25 Feb 2025 03:00:25 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1740481223; x=1741086023; darn=vger.kernel.org; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=c8AAp3JK/Rr4QIILXNDXheLWWABxs1/zeQyrDjipUFA=; b=Dbj0C96Dhw2tHrfYDpY1HGtY7aCDtprZTI1XdNJJexbBUPBrem1Y+5kJ1QMdwOwjrL 7cLxAVE/OavYW5qZHbjHPnIuz72XGzQgIwJoDNryISGbctiUe8mzG9mt7WT7K54HZBAe 3fVPLvA6ZG5Fx7tgocp2b7Q/zefzDExL3UMcP02bC8cJ+fQagWzVMR/nRomI/0GforrG 3rRHiz0Q3PGjguOYghFMGVDPFPN/1zg/B97l9nRztwtIlYKNx0xxvmtxfsxT61SxDRcW oVgkQHCudFv8sXaEHXmzUBLjKTkZru7nwNcAo2v1aukTSsRGRAL8SYxT9pSB7hwhaRc3 ZZ9Q== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1740481223; x=1741086023; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=c8AAp3JK/Rr4QIILXNDXheLWWABxs1/zeQyrDjipUFA=; b=N1IRdLvqKoJx5b3HbFqb0FqJarddMC6oOn0AnLbASuUFbpGYZ7xQIY2yk4OW9Lo0fM nKmcr1cfWUOEwlzPA9GPBbtDMavtVgF6sTAarHk7CXPkVZ6D+o5TPjXn06HaSglj41xA EKjkWWIiGCAq90NbAK5R2C+fFw4Mj/Hgj6rPXznc8a4JyruD4pL2MOY9Ew+xiQqlBuoh Dv/RrWWmhWCoqGmycjUExhm+GXKGScebM0Vm/xavL1Kg1ve9r1d8qoywhcAcHJJE9p2D c8o12DYBZ8tAryRr5Wnd+McblXQbg647fUFmZt0e7DhD/22gUimMxkcnhVaqSNEMHVoM dKww== X-Forwarded-Encrypted: i=1; AJvYcCXQswzNROtGuGkVd7nJDujr+NE9GG0Zyjt0NgW16NJteiJ8Zui7OzQoms9ttxTma4+TY4XG+1R/RwzYvT4=@vger.kernel.org X-Gm-Message-State: AOJu0YwYC6pOYTC7yKR68FnNiAlL/qP3VgfV0AG9miS2HfI4xrjMgVLj jCsK1B3eLI9LWZrT612DfcoR5Ks9EDCuOLiYZYOk3r0daBsEQtxB X-Gm-Gg: ASbGncslyT0FqOhSFG0WkY3lSTkKox6ZjIfMwqKDcCA0qbiG0rspxnhpMb/St053N8K c5v1wlqybJHgo+EC0s4NjNAUgACDpWPFeRPQqrlqZ8L3EJHZ4JTk8FCeVrmLDCK3fOedidfMTxZ dbck8w81jx/68FPzq6aus3pWYiTRDVLyIUTN/L8q44tU/yt85Ad/mqwyMu7DESXvFsZjToPHE9f Wu/rRPmcv7wlklmpJTGXMc5ntOBqLKa0PeWNDvqfmTHNZQAY7ZS3ODSN/IGQzzFsuQsP+kqFpjc A/LZc7Lf5vfRjZlD2sTsrA== X-Google-Smtp-Source: AGHT+IG45xtz1HHVnO5crMZXIQ+BrSf+jRQ/5TkER2bq6dQc/Ri7XOY6S0Xc752+lL68GgNCOEr1JA== X-Received: by 2002:a19:3806:0:b0:545:296e:ac1d with SMTP id 2adb3069b0e04-54838f5b8aamr5129849e87.51.1740481223339; Tue, 25 Feb 2025 03:00:23 -0800 (PST) Received: from pc638.lan ([2001:9b1:d5a0:a500:2d8:61ff:fec9:d743]) by smtp.gmail.com with ESMTPSA id 2adb3069b0e04-548514b9886sm143850e87.71.2025.02.25.03.00.22 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 25 Feb 2025 03:00:22 -0800 (PST) From: "Uladzislau Rezki (Sony)" To: "Paul E . McKenney" , Boqun Feng Cc: RCU , LKML , Frederic Weisbecker , Cheung Wall , Neeraj upadhyay , Joel Fernandes , Uladzislau Rezki , Oleksiy Avramchenko Subject: [PATCH v3 2/3] rcu: Update TREE05.boot to test normal synchronize_rcu() Date: Tue, 25 Feb 2025 12:00:19 +0100 Message-Id: <20250225110020.59221-2-urezki@gmail.com> X-Mailer: git-send-email 2.39.5 In-Reply-To: <20250225110020.59221-1-urezki@gmail.com> References: <20250225110020.59221-1-urezki@gmail.com> Precedence: bulk X-Mailing-List: rcu@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Add extra parameters for rcutorture module. One is the "nfakewriters" which is set -1. There will be created number of test-kthreads which correspond to number of CPUs in a test system. Those threads randomly invoke synchronize_rcu() call. Apart of that "rcu_normal" is set to 1, because it is specifically for a normal synchronize_rcu() testing, also a newly added parameter which is "rcu_normal_wake_from_gp" is set to 1 also. That prevents interaction with other callbacks in a system. Reviewed-by: Paul E. McKenney Signed-off-by: Uladzislau Rezki (Sony) --- tools/testing/selftests/rcutorture/configs/rcu/TREE05.boot | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/tools/testing/selftests/rcutorture/configs/rcu/TREE05.boot b/tools/testing/selftests/rcutorture/configs/rcu/TREE05.boot index c419cac233ee..54f5c9053474 100644 --- a/tools/testing/selftests/rcutorture/configs/rcu/TREE05.boot +++ b/tools/testing/selftests/rcutorture/configs/rcu/TREE05.boot @@ -2,3 +2,9 @@ rcutree.gp_preinit_delay=3 rcutree.gp_init_delay=3 rcutree.gp_cleanup_delay=3 rcupdate.rcu_self_test=1 + +# This part is for synchronize_rcu() testing +rcutorture.nfakewriters=-1 +rcutorture.gp_sync=1 +rcupdate.rcu_normal=1 +rcutree.rcu_normal_wake_from_gp=1 From patchwork Tue Feb 25 11:00:20 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Uladzislau Rezki X-Patchwork-Id: 13989797 Received: from mail-lf1-f44.google.com (mail-lf1-f44.google.com [209.85.167.44]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id A34A4267F62; Tue, 25 Feb 2025 11:00:26 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.167.44 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1740481228; cv=none; b=pFaUCS4Q22DZGlLSsWR1DHsf86wR/PehjNJc4BZC6NpJbTQb470Y3udpQ/53dwfWKcESZsuhqOy6GGtnbyEhjRTAa4NN8qml+ADt3ltEzh7K5ms7kexkFXQpYe+Kt9WmGXt4WUy3JOljy4WzSGsOgDCPBQNueYYVHWMdMqyw7AU= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1740481228; c=relaxed/simple; bh=4LvdbPCYHfIEA9VMVlfoNGibN70QZsOBdBupKny+JlM=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=P+eKNufaVAlNDdTgYwH/E9phkbmaA9ccCk59gnfSNsw9G0P/Sfw+pLE+Sa/Qtm/4bXj8NTf10Tk8XOuQu9JGjfgQ37AZ4gElpDxDQ8Szhm1xP2+KaU3nfLi6uVhnfiTUOaqkMYA2BrnENduE/Y8ktuviJI4S9W+XB4HmKXoNhRg= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com; spf=pass smtp.mailfrom=gmail.com; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b=m4wBJ6Kp; arc=none smtp.client-ip=209.85.167.44 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=gmail.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="m4wBJ6Kp" Received: by mail-lf1-f44.google.com with SMTP id 2adb3069b0e04-546210287c1so5581725e87.2; Tue, 25 Feb 2025 03:00:26 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1740481225; x=1741086025; darn=vger.kernel.org; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=rniMvaYIi26adKpEqcx0hyA8jOwUTjRcY3RJP/H9jWw=; b=m4wBJ6KpddcjyHTF1/czgbvXQ8ipvZdPtVh9OLxqWCrFIHArHNzeexEvdnhc9qOAH8 eVKAY6ZB+bx7ssg53Tea3/oAPckfHTQBXSzolb0lA9lGhFsDlr8IRESeg3jJ05ggZ40+ avmYsXFRGmZV4A3I2wuoFd4R6iJRsqPLk+jf8g20rYX4l/RpZqsP3db00fUnBt0w7JAo Dof0YZQ28eT2wXRj+XdL1jX/L9COeYg96U4tRwVDSGbB0KmD9KblxqSwwf3k7F2VB2j8 TZmc6mXwA+IPv0GPiFYeox4kmzlwt5YHUxnMoLzjuASy0jty93kc+Wpts26hzLH15tHr Kx1w== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1740481225; x=1741086025; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=rniMvaYIi26adKpEqcx0hyA8jOwUTjRcY3RJP/H9jWw=; b=QI7daNxEl3NjMM22yaFCxLkJXVtVQ9DbEn5XKIRAtNrVDsrLH6VgGFaepf/METzkR4 io1Jouln+D8A4d0slgWCfRrYm9qM4vU3rUOcEhG34bR/XN2p4Ri1AlID0dts1mUrNbzk KYy/TWA8vi0qORbH/LF83FGbDBYgjFi8vM9QVgzFdkdgVTU/GCTTG1y/SP+yYfBwdTyl 6pzcuDu5yoVn3uBXF0qwZ3+WqBCSs09ncDjC9fjdJDACCRyyPG3TMWQRP5fU/tz2vAxW k8xEFyI9zSFiM5FyHU7TP29tDQT47a3EM4gk+9lHqmWilj8LzfH4fJcHXxzJSLmLHxmC jPuw== X-Forwarded-Encrypted: i=1; AJvYcCVEVVk6eXHYq/S0Ulg7hzFXN74Z8pb0IfVnU8cUIy8ZeC2dGnNzdy2xP1AWQQvk1QfUegR/vlYcbW4CdVw=@vger.kernel.org X-Gm-Message-State: AOJu0YyLC/O/hHlCZ+V3hh/LZX9UVn+/l3A0rXjJ043SCbDqF8fOMPTX +Uj2DcElh06d3vhJmOVq0Wg2/Bt/KrEuXxUdgkjjiqUssX1L7ZP+ X-Gm-Gg: ASbGncss0RefhknDxo3bn9VzbFbCDUSX9O6LeQKtDclIIXOWsf7mihwFeDEHG+bM4MB 9iXbPPYzxg4zElXMz5Hdc+2bH0NA3YgF/t80RtCGBtCQR7s3dNtQqiMVGmFWCyAqtNsUPf8b7MD vADp6EytliyxvPr9EUaRzNIszj/sa60qKkoNGaezWzvRmp8trvTnYtatBWT4XKOj97C8Jdr79Ty qrfkKEP5fPty+hgXC4qjnTjdAzRUQOajn7IC43TW15GxP0NgiJMYm5J3XT8Rfpal7VXr8+ZkVBu I/Vbb44EZLemMVlZmw+8sQ== X-Google-Smtp-Source: AGHT+IFsvQXrb22vLgRYUoiA2ph8/sr59XjDMExdY1gmmRC6ZweDxkH7vhPkJt6W41kay8eJlK//cA== X-Received: by 2002:a05:6512:3a89:b0:545:2a96:34fc with SMTP id 2adb3069b0e04-5483914820dmr7023064e87.31.1740481224332; Tue, 25 Feb 2025 03:00:24 -0800 (PST) Received: from pc638.lan ([2001:9b1:d5a0:a500:2d8:61ff:fec9:d743]) by smtp.gmail.com with ESMTPSA id 2adb3069b0e04-548514b9886sm143850e87.71.2025.02.25.03.00.23 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 25 Feb 2025 03:00:23 -0800 (PST) From: "Uladzislau Rezki (Sony)" To: "Paul E . McKenney" , Boqun Feng Cc: RCU , LKML , Frederic Weisbecker , Cheung Wall , Neeraj upadhyay , Joel Fernandes , Uladzislau Rezki , Oleksiy Avramchenko Subject: [PATCH v3 3/3] rcu: Use _full() API to debug synchronize_rcu() Date: Tue, 25 Feb 2025 12:00:20 +0100 Message-Id: <20250225110020.59221-3-urezki@gmail.com> X-Mailer: git-send-email 2.39.5 In-Reply-To: <20250225110020.59221-1-urezki@gmail.com> References: <20250225110020.59221-1-urezki@gmail.com> Precedence: bulk X-Mailing-List: rcu@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Switch for using of get_state_synchronize_rcu_full() and poll_state_synchronize_rcu_full() pair for debug a normal synchronize_rcu() call. Just using "not" full APIs to identify if a grace period is passed or not might lead to a false kernel splat. Link: https://lore.kernel.org/lkml/Z5ikQeVmVdsWQrdD@pc636/T/ Fixes: 988f569ae041 ("rcu: Reduce synchronize_rcu() latency") Reported-by: cheung wall Signed-off-by: Uladzislau Rezki (Sony) Reviewed-by: Paul E. McKenney --- include/linux/rcupdate_wait.h | 3 +++ kernel/rcu/tree.c | 8 +++----- 2 files changed, 6 insertions(+), 5 deletions(-) diff --git a/include/linux/rcupdate_wait.h b/include/linux/rcupdate_wait.h index f9bed3d3f78d..4c92d4291cce 100644 --- a/include/linux/rcupdate_wait.h +++ b/include/linux/rcupdate_wait.h @@ -16,6 +16,9 @@ struct rcu_synchronize { struct rcu_head head; struct completion completion; + + /* This is for debugging. */ + struct rcu_gp_oldstate oldstate; }; void wakeme_after_rcu(struct rcu_head *head); diff --git a/kernel/rcu/tree.c b/kernel/rcu/tree.c index 8625f616c65a..48384fa2eaeb 100644 --- a/kernel/rcu/tree.c +++ b/kernel/rcu/tree.c @@ -1632,12 +1632,10 @@ static void rcu_sr_normal_complete(struct llist_node *node) { struct rcu_synchronize *rs = container_of( (struct rcu_head *) node, struct rcu_synchronize, head); - unsigned long oldstate = (unsigned long) rs->head.func; WARN_ONCE(IS_ENABLED(CONFIG_PROVE_RCU) && - !poll_state_synchronize_rcu(oldstate), - "A full grace period is not passed yet: %lu", - rcu_seq_diff(get_state_synchronize_rcu(), oldstate)); + !poll_state_synchronize_rcu_full(&rs->oldstate), + "A full grace period is not passed yet!\n"); /* Finally. */ complete(&rs->completion); @@ -3247,7 +3245,7 @@ static void synchronize_rcu_normal(void) * snapshot before adding a request. */ if (IS_ENABLED(CONFIG_PROVE_RCU)) - rs.head.func = (void *) get_state_synchronize_rcu(); + get_state_synchronize_rcu_full(&rs.oldstate); rcu_sr_normal_add_req(&rs);