From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from desiato.infradead.org (desiato.infradead.org [90.155.92.199]) (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 DE641156661; Tue, 9 Jul 2024 09:03:10 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=90.155.92.199 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1720515792; cv=none; b=Qj8J2d6VnRFM/1NVdUCsxqNB9cLnKl7AMGhXPFtUtLSt1y32uGQBSR2n0HC/YCVwV63IBY+YkqYIxawUq7fJJsSuhP96VAYiMOoXlCETpyWkZzF3p5lQzLcjk/JqxwpChfh0XwRe4WFZmg8zAYKdtz9boSnM8wgch0VOhKkMz5A= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1720515792; c=relaxed/simple; bh=7FxawhzH0ATOU2njMMmD0ZbV6K7Wu4QG9eXgUH1Glis=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=QPXYHdzmPFYPS536cIIQ4+J+VbaVyBOukljsQu1WNYx7yHhvH9DDRjqWUcmEYhYjPI0JuVcYIDSgbyqPKoE+M7fbZVX/elYOK2ZChRhgt2rUYsD6nlYmuzwrY3RiX0zj5e2x8ECAxxcFz5IBCb2KKs8gwC8uJ++siQu6JdStd3M= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=infradead.org; spf=none smtp.mailfrom=infradead.org; dkim=pass (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b=iFPUshtp; arc=none smtp.client-ip=90.155.92.199 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=infradead.org Authentication-Results: smtp.subspace.kernel.org; spf=none smtp.mailfrom=infradead.org Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="iFPUshtp" DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=desiato.20200630; h=In-Reply-To:Content-Type:MIME-Version: References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=7FxawhzH0ATOU2njMMmD0ZbV6K7Wu4QG9eXgUH1Glis=; b=iFPUshtp8vJOZL+UeRIiVLCEsr 8A6bS2uWbbynr/RJIkpVIi6MsilYWkajRxW9zLvopYHqBBdH9p8ZlDR2kAtUIpQIx1AET6rRpy3BD 5PXdFLqGblNLAMUMin9pZJ05dlxtGw8+47U8D1PiXpDi1FMb6kZJSfKP4QL+bul/QFfcs5oL3bgRb esGsGr/hOiNkbvs5QUjgxZXy3wp8P5P3XnC5Y83PpQiZun8i0VkoK2a7P161Ah6jm8TbLnrOvr0km yr2a3z5EH1BrcAMhIPKqI/sPf9dRswUFCkGOfJFvhKDQW0VJaKmofYQCyNIbLMH/B6cmfE6IO5+Ss mTbPdtGA==; Received: from j130084.upc-j.chello.nl ([24.132.130.84] helo=noisy.programming.kicks-ass.net) by desiato.infradead.org with esmtpsa (Exim 4.97.1 #2 (Red Hat Linux)) id 1sR6kb-00000000iLz-13Yv; Tue, 09 Jul 2024 09:03:05 +0000 Received: by noisy.programming.kicks-ass.net (Postfix, from userid 1000) id 38D9D3006B7; Tue, 9 Jul 2024 11:03:04 +0200 (CEST) Date: Tue, 9 Jul 2024 11:03:04 +0200 From: Peter Zijlstra To: Andrii Nakryiko Cc: Masami Hiramatsu , mingo@kernel.org, andrii@kernel.org, linux-kernel@vger.kernel.org, rostedt@goodmis.org, oleg@redhat.com, jolsa@kernel.org, clm@meta.com, paulmck@kernel.org, bpf Subject: Re: [PATCH 00/10] perf/uprobe: Optimize uprobes Message-ID: <20240709090304.GG27299@noisy.programming.kicks-ass.net> References: <20240708091241.544262971@infradead.org> <20240709075651.122204f1358f9f78d1e64b62@kernel.org> Precedence: bulk X-Mailing-List: bpf@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: On Mon, Jul 08, 2024 at 05:25:14PM -0700, Andrii Nakryiko wrote: > Ramping this up to 16 threads shows that mmap_rwsem is getting more > costly, up to 45% of CPU. SRCU is also growing a bit slower to 19% of > CPU. Is this expected? (I'm not familiar with the implementation > details) SRCU getting more expensive is a bit unexpected, it's just a per-cpu inc/dec and a full barrier. > P.S. Would you be able to rebase your patches on top of latest > probes/for-next, which include Jiri's sys_uretprobe changes. Right now > uretprobe benchmarks are quite unrepresentative because of that. What branch is that? kernel/events/ stuff usually goes through tip, no?