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 CF5D913D89D; Tue, 9 Jul 2024 10:16:44 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=90.155.50.34 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1720520206; cv=none; b=bKJkUWC7yeq6O68PlISDwmIT1uwgwlNaXQaOfRJN/r2fSJZvPlGNQC4OGqIcwnuN3Fvkfqu9CKoDK4zvCPpQmRX0ucPVMindPvaSLPPIY6tw13Mq0e28vsKLKZot6LRjxK+DEyB25tahKEzv9ghFueEFV5D7roiZbQNMG8jWd8o= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1720520206; c=relaxed/simple; bh=Dtpi1yrKRTtPk6r5zt7CiBiVsXJzpMWBZmyOj05XhgY=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=Dc4yLDkvNB7x+nVLcwx6BLMD/5Q9nMzPaU+DGNHrCFS/d9qGtRf4SXH5GIJx0faQ/QIsQZ2lZM2VrcHbCHHEdYdsauPvZ8sDpiuWCmctLnxrLbQv0oYKnsvoMgKbAYCYWLd6v3MkBL5i8+C1BPqx5o/qXmY8MY86A0h/DezvVpA= 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=hqoIfGI4; arc=none smtp.client-ip=90.155.50.34 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="hqoIfGI4" DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=casper.20170209; 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=mh5ahTlQQ1u1cc+uN8Y4hernut2vJWnu3t21K5h/yFo=; b=hqoIfGI4pB2BPewTPk/Y83AHAy 7nIAaAD/yld+8Afy4coT5a/rVwTEFYrsbHZr5TMMG8Bnshlp0kZgGYG2Q+HILcn2q6IOhdHdbWGV1 eyHR3/lRksZ4vHirOLLQQuxkrAGmWZRNUprcckTjKdgC7ZASCYe2dXUe79c6SIDbe6N51PUzjhktp JPOn3PHkLIfUUfAlIdfZ/UXiNIzGq0ezQORAc55VCGrGFBwS0TqQB38MALIq69sEKbIJ3A9/2YmWW 4jAnnAsW2gyuxqXRZuliLOGHQZB9WGHTnMrWcpbS0SlP6V1wVcKN8BP6YjqaScY/uLGRAkwKP3iAd YxvMr+9w==; Received: from j130084.upc-j.chello.nl ([24.132.130.84] helo=noisy.programming.kicks-ass.net) by casper.infradead.org with esmtpsa (Exim 4.97.1 #2 (Red Hat Linux)) id 1sR7tj-00000007mEl-0Rtr; Tue, 09 Jul 2024 10:16:35 +0000 Received: by noisy.programming.kicks-ass.net (Postfix, from userid 1000) id A87833006B7; Tue, 9 Jul 2024 12:16:34 +0200 (CEST) Date: Tue, 9 Jul 2024 12:16:34 +0200 From: Peter Zijlstra To: Jiri Olsa Cc: Andrii Nakryiko , Masami Hiramatsu , mingo@kernel.org, andrii@kernel.org, linux-kernel@vger.kernel.org, rostedt@goodmis.org, oleg@redhat.com, clm@meta.com, paulmck@kernel.org, bpf Subject: Re: [PATCH 00/10] perf/uprobe: Optimize uprobes Message-ID: <20240709101634.GJ27299@noisy.programming.kicks-ass.net> References: <20240708091241.544262971@infradead.org> <20240709075651.122204f1358f9f78d1e64b62@kernel.org> <20240709090304.GG27299@noisy.programming.kicks-ass.net> 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 Tue, Jul 09, 2024 at 12:01:03PM +0200, Jiri Olsa wrote: > On Tue, Jul 09, 2024 at 11:03:04AM +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? > > it went through the trace tree: > > https://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace.git probes/for-next > > and it's in linux-next/master already FFS :-/ That touches all sorts and doesn't have any perf ack on. Masami what gives?