From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtpout.efficios.com (smtpout.efficios.com [158.69.130.18]) (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 B3616204583 for ; Mon, 18 Aug 2025 21:38:04 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=158.69.130.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1755553086; cv=none; b=ODMO2t3jox45wGAH2+AIYaugPVNLIbXfcOaxCXp3GNJdDv6meFGZAxOfnsMYCb4j3iRPnH3Wh5VIg8FDttz5jjaMh/b9mC9zzsx7e27vMqDVjNReHjFFBdF0PDKRqsh20IPOLKShYnAmj0QxehNLZpEeJtTR9i2o+qwVBQR9r+E= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1755553086; c=relaxed/simple; bh=itBg6a1+lwB6xWkmI9LKzXQ3w1s8hkfw/strQXLc620=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=WiABVBPBWU15xZlieno8XjJOGljE2UFGvZH7LBuvCoVJ0QUt5fjBQujKlY0TcYesl0t7iYCcLO4iQVdJEKIeuHH1pZO7ndR5W1G+1fBWBkLd17oV+Of8qFuSM/V7rgVZ2bZzoNSUGUy+mFUCobXkQuXk+JXMs3GC6NWOUrXcsPE= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=efficios.com; spf=pass smtp.mailfrom=efficios.com; dkim=pass (2048-bit key) header.d=efficios.com header.i=@efficios.com header.b=semXjYdN; arc=none smtp.client-ip=158.69.130.18 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=efficios.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=efficios.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=efficios.com header.i=@efficios.com header.b="semXjYdN" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=efficios.com; s=smtpout1; t=1755552582; bh=itBg6a1+lwB6xWkmI9LKzXQ3w1s8hkfw/strQXLc620=; h=Date:Subject:To:Cc:References:From:In-Reply-To:From; b=semXjYdN1tl7rgBJVU7oyfKLIdhCMs1plWPYgJgv71HO7pbbBYS71lKHMmdjPISYP 3FjMiJkOk3YVARbfQ5dALu1BJ3QcSHvRx6WULB2vqfvsYsQrgCSI5ZktBhN2Rj5xze p2pb4kW2LJxBx0bb1D7CTwzz+vvrKXogex3nh9X0Ui0EEIHRJCAlE+ESoLrYQyNnQW +nn4mODeN+QbHs0wffFEppOhKd++kNJUkw2tJNfHFYtY02I2xDJ+ptbSjsBSbEc5mx bI4I2aDz33qe2ukbDN4PSHxJn4pTm5xKoEGJQ9wjZod/BuhbMyNc6ZngulhZ0TD3lj Tk4ATmsyHvQPg== Received: from [172.16.0.63] (192-222-132-26.qc.cable.ebox.net [192.222.132.26]) by smtpout.efficios.com (Postfix) with ESMTPSA id 4c5QpZ0JBTz1R0; Mon, 18 Aug 2025 17:29:42 -0400 (EDT) Message-ID: Date: Mon, 18 Aug 2025 17:29:41 -0400 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Betterbird (Linux) Subject: Re: [patch 00/11] rseq: Optimize exit to user space To: Thomas Gleixner , Jens Axboe , LKML Cc: Mathieu Desnoyers , Peter Zijlstra , "Paul E. McKenney" , Boqun Feng , Wei Liu References: <20250813155941.014821755@linutronix.de> <12342355-b3fb-4e78-ad5b-dcfff1366ccf@kernel.dk> <87bjoi7vqx.ffs@tglx> <6b428c1f-4118-4ede-8674-eceee96036c1@kernel.dk> <877bz67u3j.ffs@tglx> <87y0rh63t0.ffs@tglx> <87a53wxtx5.ffs@tglx> From: Michael Jeanson Content-Language: fr Autocrypt: addr=mjeanson@efficios.com; keydata= xsFNBE0j2GkBEACcli1fPgaQ/9lCQA8xCtMmGARVfTzhyIstl41wnBdEijU6RN3EzzPc8j1i fsdK6DBEWLEoQBkFZLPmq+HJ1sNsUsJRe9OzYuetcSvDRPu8XEsLkO8akmC3fo5/Pk6iLnRb +Ge0nsNii5CSULPnHUgCxyBGcKm8hWqB4m/t79MOXHDAHNQt6ecP0ss86/vLMXpzLg9yyXBu sY1HrHMbUNssE0kqMgEmoq3v6JRwK9Qv1WDmNzl3UgMd2WZKUv0sQjyOCh/13R8Clk8Ljjnc n/RrHp6XIWreXZRTU0cL9ZfFjTntci82Je5pKWiLSaNAIHKFo8AMwvum52SqSxA76YkcNyGk 9S8O3A6tQAhZkl4rn2eF3qd1I33G+8gyvFuL8omP566rJ0PnF2hDP5FqKcbpUjs6eMWLqPYD 6AirkGurX1FmA7gg6MAiOuLptcGPYslavQK6gmcYtnjVYfueEpBzj/6jl0b3gpVYmGd/e52f mU6krF0By/Ch0Nmk3YDPuhEig4jWXmvov0BTcVFKdS7Axxh8pdZYcgz87gBgsqr90Rg7ioLB ldgI/698cXNlBWGWRvxshbEXidQF3dgksTafWylLYQVCPCHXYcVXkpoHfsEBKYKTIezT7CCA EvSDlN4X+ncIzRg5CeS3bzs4HrusiOdOjaSkVdifwQxzhvn4RQARAQABzSdNaWNoYWVsIEpl YW5zb24gPG1qZWFuc29uQGVmZmljaW9zLmNvbT7CwZQEEwEKAD4CGwMFCwkIBwMFFQoJCAsF FgIDAQACHgECF4AWIQSYZiQyQrZCJ3niC2KGVh9FIYD8/gUCZ//KEgUJHeiBpwAKCRCGVh9F IYD8/mhQD/wOShaTLm2UjDz1VwDM5l0gxfnwqG/xc69G+eDsXQoL+Ad2kc4cTKGXnkFxW/hN QMZ9dG3LeD1oqfIYSQaUC3OUZPSE07r6kH4UMkFFY6XUhBBONHD/lqGaY7FsvrPSVKo3T3GA Bc7bD/OsSgvWNyKktfxFbzm4SzO7N0ALBMC4qEaaJW68bfM/ID4Sx1gNFUFa88qghjgizfzO +4aHkxQ4MlfZ1nN0UxISlWxKt2YqfPcUdjl+8nDk0je1/6nKA9qXLBB5fbONXBGe1Bm7yiqz AlGIVJpfEKl6r74YdYzNSKuHIOAaHY5BJ5MX/0EyBAp7t6jGvt1WCqO+R3JBZnQ+/F2JFaXc aI1ay4F1ermRxcSWrxJw/XNIKNfFzgWDKceBAz+U0RUjvtDjqlZ60znh3+oAplvzkfddptQe /WDzWsCIxRnaD0aFcIiKxPc7QqkK1W60/UCjoSXDkbN4A/xa0LmiMMFJErpyRagaetQ6F13y 9oVgO7/W9ooiCTI67wymX8hBMyVZ5NttXzuNmx0TWmI29ZoBMUIaitJ8GBZI9Jxs+SpReear B0935ie2oYr3p+Dm+rGLqIbKTIrLr6o6Bc8bV/RYcMa23qXe4n67nKZJv3jU/GL3o9zobguc EoUUWe9NbBDrbi63Dz/gcGWuUSxLgpiP9i8vlGywGz/Jx87BTQRNI9hpARAAqAkuPLkp3WkX Q/aUKgHM9bVA3Qzx1lx7Cmvhpa9Rn435ciJdf0xEmv1xVwYGjsoMgStX9sb1PzBZePsJGbQ1 rW57hTkgvwqGduDPjbgVVjZ4nHYpfPzggTdm+DOpkAUvUVTRNTe4k6B8Pd/BJYu4TrBM2dLh cNakLzg3Q4rI/2AsOCOjPuRVhClILzaEttksG9KzMyFUxwVr1NAkynZLnjSQyGqKAw71DnRT vzmf3lyG1dY/DSwJyEiV8LOd1Gno6c8F6CTuow3c/J7Ttc5+9MDBiQxySwOH2Xp3ROKUtIbj Quw3cjtkTRrRknZm2EbVrB1C+KF9tAeAVNDkqfQrrdwL9Uvn9EjuHhCVsqIN+WvoJFYoIyhl HUy9uQhWQNn5G/9SNQK3BFAmJhgt64CPBIsOu3mpvMQtZHtJ8Hpfub5Uueew/MJlkYGWr1IG DjrAgDWBYSXTvqcvLpt4Yrp3RqRAsOoKKjomcFv5S0ryTQLO/aaZVTKzha41FxIhd+zUg6/r vc6RWKL+ySS1fOeFk+SaY1GeFLMoT9MgUEXHIkISC1xdA5Zri13MBxkcJkd5sZ/0C5Wlgr+f LuuzzcZX9aDiiV4uAdmy5WHVo6Y/l6MtYq+Fbzp0LSU2KemigHIGZT/gL+zDvduDIZjQZeG4 gNxM1wwsycfIYftHMfg8OVEAEQEAAcLBfAQYAQoAJgIbDBYhBJhmJDJCtkIneeILYoZWH0Uh gPz+BQJn/8o/BQkd6IGnAAoJEIZWH0UhgPz+Y3YQAJJaKODzmQMlxJ7kNTOjBo4wemDo6e5d kJ7xhYinLru+G8qJS0m7EsO51o3WtvrsPFV+RyKQrVW/Sl3m9dK/KxCWewW1itu4OKeHd+k5 UUK7xZg7lbmPFeoIaP0JtS96My0SnWRdRVSh+tQlqC4LlNIw3CiRxrCkfPlsoOBzZkTcx8Ta oYez+F0KKSH4SIk/+tgUvCAkb3JCw3kz5LxmV2NpgsvI6R5uuQ7nLtgEA6Q9g+ahICs0g+w+ HqSU1W+o6xrYZuCej1CFn3bqNuuAQGgVlD4wyS9SbXyCD5AZZwqX0V11C60AhInxCqnpn1hP qusWfhXf0BJeRNzKo7TMd3aB1YnsieNQQRopM4S8D2Embe9DtBX0WeUR/fDGjHiPItkFSel9 Gl6aXqDWDdaf1tKr4eQc845/EljpQF1LxHTp4kpGcyT5IqsA+Xom0lRowFimTwrLkHbAU+6P 3rAy/6dOzcikgkVYGln6nSgZsqeLlOyLUEE0+WpSbR4UxaMjvcM8PIx5rX6FuQxJslQ52emr 2XM0IYMuU6/5TMyTaQdS4p2nu2qu99snefOikIUzAxAp+Y5es/Tazwb83VdEGoN6JxzauDeQ upVaTHEZj/GMlMPGw05QXmB8rQz0aWTGpVBZFpmBWHYsk3QVEAOjQbjMfESW/IHw9EMZs/NH IZHa In-Reply-To: <87a53wxtx5.ffs@tglx> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit On 2025-08-18 16:21, Thomas Gleixner wrote: > That looks about right. Can you reset the branch to > > commit 85b61b265635 ("rseq: Expose stats") > > which is just adding primitive stats on top of the current mainline > code, and provide numbers for that too? > > That gives you 'notify: , cpuid:, fixup:' numbers, which are not 1:1 > mappable to the final ones, but that should give some interesting > insight. For amd64 kernel and userspace. Before: notify: 12467 fixup: 12467 cpuid: 12467 After: notify: 123669528 fixup: 123669528 cpuid: 123669528 For amd64 kernel, i386 userspace. Before: notify: 12857 fixup: 12857 cpuid: 12857 After: notify: 120621210 fixup: 120621210 cpuid: 120621210 > Might be useful to put such instructions into README.md, no? Will do. Regards, Michael