From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from casper.infradead.org (casper.infradead.org [90.155.50.34]) (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 61EEE8BE0 for ; Tue, 13 Jun 2023 07:39:42 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=casper.20170209; h=In-Reply-To:Content-Transfer-Encoding: Content-Type:MIME-Version:References:Message-ID:Subject:Cc:To:From:Date: Sender:Reply-To:Content-ID:Content-Description; bh=taRVbZGY7eAXHJhyY2OAnvNRfmEw/YGDeNE955RAneg=; b=k4xtU11ThlaltSx7EZ6bcj9NVM jy2pArA60NPwrh9HNHBpuN7tipRcFFa6LF0Ho5HJ09urAyeEeo9x+tHuTRLQqI4jmmpIfvFGeA+R3 GgE8ltvsU2jxQCspcV88ZdKNCNe5LkviACAE5b0QDSE+YGW+sX4G+Bd0dTXPRRZ8pUBdmDOWkDer6 o5eblE26lIHMvBDtTSc6etUPEDdl5sPeHfwJTN9dG09IEHDr9TS9JtQIjNNy+TzVwQDP/eXFDNj8x 09Q+1O03XzlZv8euV6/8o4g4uLsiRie4O/r+QkPfTCGMXevL2+dRtykPrih20ct5YufDXQUdYKMmN 2U3jdLTA==; Received: from j130084.upc-j.chello.nl ([24.132.130.84] helo=noisy.programming.kicks-ass.net) by casper.infradead.org with esmtpsa (Exim 4.94.2 #2 (Red Hat Linux)) id 1q8ycW-003fAJ-IC; Tue, 13 Jun 2023 07:39:16 +0000 Received: from hirez.programming.kicks-ass.net (hirez.programming.kicks-ass.net [192.168.1.225]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits)) (Client did not present a certificate) by noisy.programming.kicks-ass.net (Postfix) with ESMTPS id DF59F300188; Tue, 13 Jun 2023 09:39:14 +0200 (CEST) Received: by hirez.programming.kicks-ass.net (Postfix, from userid 1000) id C5A342C8E889C; Tue, 13 Jun 2023 09:39:14 +0200 (CEST) Date: Tue, 13 Jun 2023 09:39:14 +0200 From: Peter Zijlstra To: Namhyung Kim Cc: torvalds@linux-foundation.org, keescook@chromium.org, gregkh@linuxfoundation.org, pbonzini@redhat.com, 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, 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, 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: Re: [PATCH v3 26/57] perf: Simplify event_function*() Message-ID: <20230613073914.GQ4253@hirez.programming.kicks-ass.net> References: <20230612090713.652690195@infradead.org> <20230612093539.371360635@infradead.org> Precedence: bulk X-Mailing-List: llvm@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: On Mon, Jun 12, 2023 at 10:56:06PM -0700, Namhyung Kim wrote: > Hi Peter, > > On Mon, Jun 12, 2023 at 2:39 AM Peter Zijlstra wrote: > > > > Use guards to reduce gotos and simplify control flow. > > > > Signed-off-by: Peter Zijlstra (Intel) > > --- > > kernel/events/core.c | 39 ++++++++++++++++++++++++++------------- > > 1 file changed, 26 insertions(+), 13 deletions(-) > > > > --- a/kernel/events/core.c > > +++ b/kernel/events/core.c > > @@ -214,6 +214,25 @@ struct event_function_struct { > > void *data; > > }; > > > > +typedef struct { > > + struct perf_cpu_context *cpuctx; > > + struct perf_event_context *ctx; > > +} class_perf_ctx_lock_t; > > + > > +static inline void class_perf_ctx_lock_destructor(class_perf_ctx_lock_t *_T) > > +{ > > + if (_T->cpuctx) > > + perf_ctx_unlock(_T->cpuctx, _T->ctx); > > Shouldn't it be called unconditionally? In all surviving cases it will be, so yeah, I can remove that condition.