From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 A0B214A04; Wed, 10 Jul 2024 00:55:26 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1720572927; cv=none; b=JEDlfqRDwyF9jsWmaN7aDFjNl19vbimATPRI2Tw25mwgOnNFeKYCn5W1iuQq7VHMhETsYhOSgQK8Y04bRZt9O1rXTcF76/dImaUqyyflRfA8prmxJ80uEkX2QOTLfDjATBlXr2Nt5rsC1RxWF5vK96VUUJ8n4jRqrVbWxvSuVss= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1720572927; c=relaxed/simple; bh=bitPg8LD4gcptSNxQJP5YQUYZFMEYZzkW1TRSoUqBFY=; h=Date:From:To:Cc:Subject:Message-Id:In-Reply-To:References: Mime-Version:Content-Type; b=CtdMZsq6qEL04TXdz4Km0SUU/pBXyES1l67a21Ej4Mlqjqek4Mbw21BR1sSBw72N5W0SxPHjhLxG9LR8cLiN355YFIC7jMThvc3fF8AC+hrF9EW2XzQovugEJsbVdtEWTyLnUk4MEkjsnAkU/D/0DySKMNbh6/Z/8p4w0QkLJSQ= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=OHn1xkxh; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="OHn1xkxh" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 58FB9C3277B; Wed, 10 Jul 2024 00:55:23 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1720572926; bh=bitPg8LD4gcptSNxQJP5YQUYZFMEYZzkW1TRSoUqBFY=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=OHn1xkxhzgNFs/A5esmTp5dqfG4QCJKvPs5hbYcZ6xrWoGosRGawuXCfcH8npeEEU MxZ1ludRolX7Tufd+C2q9DTrC0SPGxpV9Y6WkDuT2OlIwgOhpqUXYoUQ5MTbKKUnTp 6UwTPtjMQc8YFQImqSt5GgTWZA7KWjx0CmjUFJvapbYIGapkJtgoPjz79EiguR4Tyn 1PMN/i9OUkqT4YIoLrJmmRyqHRv+RqMIMjdGgEMa5n2DR2D55AK5/Vvr3I5mIaKgZK RtOrjmWsUR9aLfzC3pASheaF+hd3OFZcX9fiHcFmVDSwOMvPJuIUj4itutUz4Szqnk Z+xkYOazL0EZA== Date: Wed, 10 Jul 2024 09:55:20 +0900 From: Masami Hiramatsu (Google) To: Peter Zijlstra Cc: Andrii Nakryiko , 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: <20240710095520.e6cbfa6efac9bd79f248b111@kernel.org> In-Reply-To: <20240709090304.GG27299@noisy.programming.kicks-ass.net> References: <20240708091241.544262971@infradead.org> <20240709075651.122204f1358f9f78d1e64b62@kernel.org> <20240709090304.GG27299@noisy.programming.kicks-ass.net> X-Mailer: Sylpheed 3.7.0 (GTK+ 2.24.33; x86_64-pc-linux-gnu) 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-Transfer-Encoding: 7bit On Tue, 9 Jul 2024 11:03:04 +0200 Peter Zijlstra wrote: > 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? I'm handling uprobe patches in linux-trace tree, because it's a kind of probes in the kernel. Actually that is not clarified that the uprobe is handled by which tree. I had asked to handle kprobes in linux-trace, but uprobes might not be clear. Is that OK for you to handle uprobes on linux-trace? Thank you, -- Masami Hiramatsu (Google)