From patchwork Mon Jun 12 09:07:45 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Peter Zijlstra X-Patchwork-Id: 13276195 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id EE48CC7EE43 for ; Mon, 12 Jun 2023 09:58:46 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229877AbjFLJ6n (ORCPT ); Mon, 12 Jun 2023 05:58:43 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:60832 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234688AbjFLJy6 (ORCPT ); Mon, 12 Jun 2023 05:54:58 -0400 Received: from desiato.infradead.org (desiato.infradead.org [IPv6:2001:8b0:10b:1:d65d:64ff:fe57:4e05]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 94603619E; Mon, 12 Jun 2023 02:39:38 -0700 (PDT) DKIM-Signature: v=1; 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Mon, 12 Jun 2023 11:38:53 +0200 (CEST) Received: by hirez.programming.kicks-ass.net (Postfix, from userid 0) id AE93C30A77B6A; Mon, 12 Jun 2023 11:38:48 +0200 (CEST) Message-ID: <20230612093539.823493926@infradead.org> User-Agent: quilt/0.66 Date: Mon, 12 Jun 2023 11:07:45 +0200 From: Peter Zijlstra To: torvalds@linux-foundation.org, keescook@chromium.org, gregkh@linuxfoundation.org, pbonzini@redhat.com Cc: masahiroy@kernel.org, nathan@kernel.org, ndesaulniers@google.com, nicolas@fjasle.eu, catalin.marinas@arm.com, will@kernel.org, vkoul@kernel.org, trix@redhat.com, ojeda@kernel.org, peterz@infradead.org, mingo@redhat.com, longman@redhat.com, boqun.feng@gmail.com, dennis@kernel.org, tj@kernel.org, cl@linux.com, acme@kernel.org, mark.rutland@arm.com, alexander.shishkin@linux.intel.com, jolsa@kernel.org, namhyung@kernel.org, irogers@google.com, adrian.hunter@intel.com, juri.lelli@redhat.com, vincent.guittot@linaro.org, dietmar.eggemann@arm.com, rostedt@goodmis.org, bsegall@google.com, mgorman@suse.de, bristot@redhat.com, vschneid@redhat.com, paulmck@kernel.org, frederic@kernel.org, quic_neeraju@quicinc.com, joel@joelfernandes.org, josh@joshtriplett.org, mathieu.desnoyers@efficios.com, jiangshanlai@gmail.com, rientjes@google.com, vbabka@suse.cz, roman.gushchin@linux.dev, 42.hyeyoo@gmail.com, apw@canonical.com, joe@perches.com, dwaipayanray1@gmail.com, lukas.bulwahn@gmail.com, john.johansen@canonical.com, paul@paul-moore.com, jmorris@namei.org, serge@hallyn.com, linux-kbuild@vger.kernel.org, linux-kernel@vger.kernel.org, dmaengine@vger.kernel.org, llvm@lists.linux.dev, linux-perf-users@vger.kernel.org, rcu@vger.kernel.org, linux-security-module@vger.kernel.org, tglx@linutronix.de, ravi.bangoria@amd.com, error27@gmail.com, luc.vanoostenryck@gmail.com Subject: [PATCH v3 32/57] perf: Simplify perf_event_context_sched_in() References: <20230612090713.652690195@infradead.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: rcu@vger.kernel.org Signed-off-by: Peter Zijlstra (Intel) --- kernel/events/core.c | 38 +++++++++++++++----------------------- 1 file changed, 15 insertions(+), 23 deletions(-) --- a/kernel/events/core.c +++ b/kernel/events/core.c @@ -713,6 +713,9 @@ static void perf_ctx_enable(struct perf_ perf_pmu_enable(pmu_ctx->pmu); } +DEFINE_GUARD(perf_ctx_disable, struct perf_event_context *, + perf_ctx_disable(_T), perf_ctx_enable(_T)) + static void ctx_sched_out(struct perf_event_context *ctx, enum event_type_t event_type); static void ctx_sched_in(struct perf_event_context *ctx, enum event_type_t event_type); @@ -3906,31 +3909,27 @@ static void perf_event_context_sched_in( struct perf_cpu_context *cpuctx = this_cpu_ptr(&perf_cpu_context); struct perf_event_context *ctx; - rcu_read_lock(); + guard(rcu)(); + ctx = rcu_dereference(task->perf_event_ctxp); if (!ctx) - goto rcu_unlock; - - if (cpuctx->task_ctx == ctx) { - perf_ctx_lock(cpuctx, ctx); - perf_ctx_disable(ctx); - - perf_ctx_sched_task_cb(ctx, true); - - perf_ctx_enable(ctx); - perf_ctx_unlock(cpuctx, ctx); - goto rcu_unlock; - } + return; - perf_ctx_lock(cpuctx, ctx); + guard(perf_ctx_lock)(cpuctx, ctx); /* * We must check ctx->nr_events while holding ctx->lock, such * that we serialize against perf_install_in_context(). */ if (!ctx->nr_events) - goto unlock; + return; + + guard(perf_ctx_disable)(ctx); + + if (cpuctx->task_ctx == ctx) { + perf_ctx_sched_task_cb(ctx, true); + return; + } - perf_ctx_disable(ctx); /* * We want to keep the following priority order: * cpu pinned (that don't need to move), task pinned, @@ -3950,13 +3949,6 @@ static void perf_event_context_sched_in( if (!RB_EMPTY_ROOT(&ctx->pinned_groups.tree)) perf_ctx_enable(&cpuctx->ctx); - - perf_ctx_enable(ctx); - -unlock: - perf_ctx_unlock(cpuctx, ctx); -rcu_unlock: - rcu_read_unlock(); } /*