From patchwork Thu Jul 20 16:30:44 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Valentin Schneider X-Patchwork-Id: 13320775 Received: from lindbergh.monkeyblade.net (lindbergh.monkeyblade.net [23.128.96.19]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 72F6E26B38 for ; Thu, 20 Jul 2023 16:33:19 +0000 (UTC) Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 47B871995 for ; Thu, 20 Jul 2023 09:33:10 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1689870789; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=v3SClOtTb5K9y8gZXjCHv42uNQ6hcmWjrBQMdqu658k=; b=FXCpGhxf099W5Sbt2clRAU9QYQGFmblbI7YoqZKcQIAAFZp3Jawdyy6X2vItRNJfye0IMu ORaLZUmYoZ7hs5eylJDKhb6SqCVFe1f7g5VK/b8gnqGfBOf0m2Zi/DiY+Ndj+oYYBAljck bMnmLvpvN5zk2SCzrbvL8RTKV28w8JI= Received: from mimecast-mx02.redhat.com (mimecast-mx02.redhat.com [66.187.233.88]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-6-SbuvRRjOPo6HLoecNE0CHQ-1; Thu, 20 Jul 2023 12:33:05 -0400 X-MC-Unique: SbuvRRjOPo6HLoecNE0CHQ-1 Received: from smtp.corp.redhat.com (int-mx01.intmail.prod.int.rdu2.redhat.com [10.11.54.1]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 6DD1A101156F; Thu, 20 Jul 2023 16:33:02 +0000 (UTC) Received: from vschneid.remote.csb (unknown [10.42.28.48]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 1270F40C206F; Thu, 20 Jul 2023 16:32:54 +0000 (UTC) From: Valentin Schneider To: linux-kernel@vger.kernel.org, linux-trace-kernel@vger.kernel.org, linux-doc@vger.kernel.org, kvm@vger.kernel.org, linux-mm@kvack.org, bpf@vger.kernel.org, x86@kernel.org, rcu@vger.kernel.org, linux-kselftest@vger.kernel.org Cc: Steven Rostedt , Masami Hiramatsu , Jonathan Corbet , Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , "H. Peter Anvin" , Paolo Bonzini , Wanpeng Li , Vitaly Kuznetsov , Andy Lutomirski , Peter Zijlstra , Frederic Weisbecker , "Paul E. McKenney" , Neeraj Upadhyay , Joel Fernandes , Josh Triplett , Boqun Feng , Mathieu Desnoyers , Lai Jiangshan , Zqiang , Andrew Morton , Uladzislau Rezki , Christoph Hellwig , Lorenzo Stoakes , Josh Poimboeuf , Jason Baron , Kees Cook , Sami Tolvanen , Ard Biesheuvel , Nicholas Piggin , Juerg Haefliger , Nicolas Saenz Julienne , "Kirill A. Shutemov" , Nadav Amit , Dan Carpenter , Chuang Wang , Yang Jihong , Petr Mladek , "Jason A. Donenfeld" , Song Liu , Julian Pidancet , Tom Lendacky , Dionna Glaze , =?utf-8?q?Thomas_Wei=C3=9Fschuh?= , Juri Lelli , Daniel Bristot de Oliveira , Marcelo Tosatti , Yair Podemsky Subject: [RFC PATCH v2 08/20] tracing/filters: Further optimise scalar vs cpumask comparison Date: Thu, 20 Jul 2023 17:30:44 +0100 Message-Id: <20230720163056.2564824-9-vschneid@redhat.com> In-Reply-To: <20230720163056.2564824-1-vschneid@redhat.com> References: <20230720163056.2564824-1-vschneid@redhat.com> Precedence: bulk X-Mailing-List: bpf@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.1 on 10.11.54.1 X-Spam-Status: No, score=-2.1 required=5.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,RCVD_IN_DNSWL_NONE, RCVD_IN_MSPIKE_H4,RCVD_IN_MSPIKE_WL,SPF_HELO_NONE,SPF_NONE, T_SCC_BODY_TEXT_LINE autolearn=unavailable autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net X-Patchwork-State: RFC Per the previous commits, we now only enter do_filter_scalar_cpumask() with a mask of weight greater than one. Optimise the equality checks. Suggested-by: Steven Rostedt Signed-off-by: Valentin Schneider --- kernel/trace/trace_events_filter.c | 26 ++++++++++++++++++++------ 1 file changed, 20 insertions(+), 6 deletions(-) diff --git a/kernel/trace/trace_events_filter.c b/kernel/trace/trace_events_filter.c index fd72dacc5d1b8..3a529214a21b7 100644 --- a/kernel/trace/trace_events_filter.c +++ b/kernel/trace/trace_events_filter.c @@ -667,6 +667,25 @@ do_filter_cpumask(int op, const struct cpumask *mask, const struct cpumask *cmp) /* Optimisation of do_filter_cpumask() for scalar fields */ static inline int do_filter_scalar_cpumask(int op, unsigned int cpu, const struct cpumask *mask) +{ + /* + * Per the weight-of-one cpumask optimisations, the mask passed in this + * function has a weight >= 2, so it is never equal to a single scalar. + */ + switch (op) { + case OP_EQ: + return false; + case OP_NE: + return true; + case OP_BAND: + return cpumask_test_cpu(cpu, mask); + default: + return 0; + } +} + +static inline int +do_filter_cpumask_scalar(int op, const struct cpumask *mask, unsigned int cpu) { switch (op) { case OP_EQ: @@ -966,12 +985,7 @@ static int filter_pred_cpumask_cpu(struct filter_pred *pred, void *event) const struct cpumask *mask = (event + loc); unsigned int cpu = pred->val; - /* - * This inverts the usual usage of the function (field is first element, - * user parameter is second), but that's fine because the (scalar, mask) - * operations used are symmetric. - */ - return do_filter_scalar_cpumask(pred->op, cpu, mask); + return do_filter_cpumask_scalar(pred->op, mask, cpu); } /* Filter predicate for COMM. */