From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) (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 0873A20B21D for ; Wed, 5 Mar 2025 15:22:36 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=170.10.133.124 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1741188161; cv=none; b=BPpBMzIlAonqxQVoLgTQDfecl544NUbvXxrOEchgNRcHcQCCSh6u4G8cNgJZnKUj1kPmHg5yvNpls+SesJChCQsUV9g+V5YFqfFSv5GV1zil3UgKm7VSU8N7fbb+6fZpRCWx+DtPbZUirEG0WnnLsullboTtKs8uth0sGn4le3M= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1741188161; c=relaxed/simple; bh=VWigdSJtvf2WxMxfGPfKwCzDKILPSKtbmZRomoBqut8=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=PEV269YDbrkz0crzZDlE3p7cg2mkD+pnXp2NcHFjMoMJxbu4Y9MmtFT82Zs1jp+jZ78YARoLCz/u+n10rrPL888ZhFuJV9ju4lAPfmdXHS2RPqLXS49Nk5OAt8OzlObZONc9QewmwdRi309UMTRIeEU8HylcHTeao3uQ1OPFUK8= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=redhat.com; spf=pass smtp.mailfrom=redhat.com; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b=N5Ri+XO0; arc=none smtp.client-ip=170.10.133.124 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=redhat.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=redhat.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="N5Ri+XO0" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1741188151; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=VWigdSJtvf2WxMxfGPfKwCzDKILPSKtbmZRomoBqut8=; b=N5Ri+XO0E6mhK6mtORn3W1Tte72px9kJSHNz0pbNnmVhlp4srU6B3XFH+2QqmdSyMwyB7M 2tJY9cGxyZzy0g6MOkABGGbPB5otX+F7sAlFJnhpuU9w4/LRssMbRb3JGwSyfTTc5uWMg/ Q6ARAx3pRmeevukxFYVrH3MlodOZ+jk= Received: from mx-prod-mc-08.mail-002.prod.us-west-2.aws.redhat.com (ec2-35-165-154-97.us-west-2.compute.amazonaws.com [35.165.154.97]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-696-23qFcZJ4NrSH5Me2lVeGFg-1; Wed, 05 Mar 2025 10:21:55 -0500 X-MC-Unique: 23qFcZJ4NrSH5Me2lVeGFg-1 X-Mimecast-MFC-AGG-ID: 23qFcZJ4NrSH5Me2lVeGFg_1741188097 Received: from mx-prod-int-06.mail-002.prod.us-west-2.aws.redhat.com (mx-prod-int-06.mail-002.prod.us-west-2.aws.redhat.com [10.30.177.93]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mx-prod-mc-08.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id C55451801A07; Wed, 5 Mar 2025 15:21:35 +0000 (UTC) Received: from dhcp-27-174.brq.redhat.com (unknown [10.44.34.66]) by mx-prod-int-06.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with SMTP id B2E781800266; Wed, 5 Mar 2025 15:21:27 +0000 (UTC) Received: by dhcp-27-174.brq.redhat.com (nbSMTP-1.00) for uid 1000 oleg@redhat.com; Wed, 5 Mar 2025 16:21:05 +0100 (CET) Date: Wed, 5 Mar 2025 16:20:55 +0100 From: Oleg Nesterov To: David Hildenbrand , Andrii Nakryiko , Jiri Olsa Cc: linux-kernel@vger.kernel.org, linux-mm@kvack.org, linux-arm-kernel@lists.infradead.org, linux-trace-kernel@vger.kernel.org, linux-perf-users@vger.kernel.org, Andrew Morton , Matthew Wilcox , Russell King , Masami Hiramatsu , Peter Zijlstra , Ingo Molnar , Arnaldo Carvalho de Melo , Namhyung Kim , Mark Rutland , Alexander Shishkin , Ian Rogers , Adrian Hunter , "Liang, Kan" , Tong Tiangen Subject: Re: [PATCH -next v1 0/3] kernel/events/uprobes: uprobe_write_opcode() rewrite Message-ID: <20250305152055.GB28112@redhat.com> References: <20250304154846.1937958-1-david@redhat.com> Precedence: bulk X-Mailing-List: linux-perf-users@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: <20250304154846.1937958-1-david@redhat.com> User-Agent: Mutt/1.5.24 (2015-08-30) X-Scanned-By: MIMEDefang 3.4.1 on 10.30.177.93 On 03/04, David Hildenbrand wrote: > > Currently, uprobe_write_opcode() implements COW-breaking manually, which is > really far from ideal. To say at least ;) David, thanks for doing this. I'll try to read 3/3 tomorrow, but I don't think I can really help. Let me repeat, this code was written many years ago, I forgot everything, and today my understanding of mm/ is very poor. But I'll try anyway. > Are there any uprobe tests / benchmarks that are worth running? All I know about uprobe tests is that bpf people run a lot of tests which use uprobes. Andrii, Jiri, what you advise? Oleg.