From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from galois.linutronix.de (Galois.linutronix.de [193.142.43.55]) (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 4C68827280C; Fri, 12 Dec 2025 01:12:17 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=193.142.43.55 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1765501939; cv=none; b=r1c366XWAzY4QzU/oRMdQ0WFtAd4J1NlVbA+epdbYBRP8U4VoEqq8EsQsGvw0EydurN5s4i7Pd2JocIcOcMFIQbiIG9aS1tzURMXuwIJN85wvvavxrbzKOtndFSVynjqzqy0qsbiUmIZTM9Od3lIaPghCxHUjIKK/Nr20uZriDE= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1765501939; c=relaxed/simple; bh=5hWXJxhX5wME82FGFIrBRzJRgBsQr+OdqP9sUt7Njis=; h=From:To:Subject:In-Reply-To:References:Date:Message-ID: MIME-Version:Content-Type; b=lhZloGHPspCQOYHaH0TbBE5q2DtQhvIvzJJnJ1XY0kn4zExBQYSSvhtlSHz0lDzDVjCln9RHQnvcubpeacNG9bQLj2Ud1vD1IDTD6o2UAzjKJXzSabsI18I5ofQCtAmFDbkxb5GZVo/8VYrj4Arojd3vwSvaIvxLNzEwD8INCs4= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linutronix.de; spf=pass smtp.mailfrom=linutronix.de; dkim=pass (2048-bit key) header.d=linutronix.de header.i=@linutronix.de header.b=VI3pH1Vc; dkim=permerror (0-bit key) header.d=linutronix.de header.i=@linutronix.de header.b=wX3HdKaa; arc=none smtp.client-ip=193.142.43.55 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linutronix.de Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linutronix.de Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=linutronix.de header.i=@linutronix.de header.b="VI3pH1Vc"; dkim=permerror (0-bit key) header.d=linutronix.de header.i=@linutronix.de header.b="wX3HdKaa" From: Thomas Gleixner DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1765501936; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=5hWXJxhX5wME82FGFIrBRzJRgBsQr+OdqP9sUt7Njis=; b=VI3pH1VcrifbeS9kA3FPBSHylFeLOXjGAye2KPD1jpu3JUjgxWpVrJ7FpQfVodUHXTPATC PQlw6QNdJC8x3jc3F7/cvot67LJEbPwOVjjCuGOKF06aYRXBEKuXVBjTQO3rNVN8b2hBhQ Yl3yor8zKz7LVv5/SB23naFPfsbs5EwQ7Sn0p2S7wqJ1UN1eZTVTiZ2WWwZW//z9vYv3rD OhKN3zFynVYPnDa1v3JPtxSB+ZVXKoeQCfCyW7TiojfhNwEq77I79urwK+TPPzwrc5K/mN UpjuzcfUNuBZI3bD4d7Ah5IJ51GjTwUwJC5bk3pkqA4qB+e4NbGbrSFULQvOTw== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1765501936; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=5hWXJxhX5wME82FGFIrBRzJRgBsQr+OdqP9sUt7Njis=; b=wX3HdKaaXflaOMKhWkolNsCkdzaVm6/IgPyOJ8qgM/d5MMYeT9V0ed4WOBgPjrqHHa52MA 7L1NceDmnev/reDQ== To: Kevin Brodsky , Jinjie Ruan , catalin.marinas@arm.com, will@kernel.org, oleg@redhat.com, peterz@infradead.org, luto@kernel.org, shuah@kernel.org, kees@kernel.org, wad@chromium.org, deller@gmx.de, macro@orcam.me.uk, charlie@rivosinc.com, ldv@strace.io, mark.rutland@arm.com, song@kernel.org, ryan.roberts@arm.com, ada.coupriediaz@arm.com, anshuman.khandual@arm.com, broonie@kernel.org, pengcan@kylinos.cn, dvyukov@google.com, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, linux-kselftest@vger.kernel.org Subject: Re: [PATCH v9 15/16] entry: Inline syscall_exit_work() In-Reply-To: References: <20251204082123.2792067-1-ruanjinjie@huawei.com> <20251204082123.2792067-16-ruanjinjie@huawei.com> <87345hfqyh.ffs@tglx> Date: Fri, 12 Dec 2025 10:12:13 +0900 Message-ID: <87wm2sec5u.ffs@tglx> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain On Thu, Dec 11 2025 at 10:52, Kevin Brodsky wrote: > On 11/12/2025 07:55, Thomas Gleixner wrote: >> I have a suspicion that it is TIF_NOTIFY_RESUME. If that's the case >> you're seing the RSEQ overhead, which should be completely gone with the >> rewrite that got just merged into Linus tree. > > I don't think this is related. This patch inlines syscall_exit_work(), > which is called if some flag in SYSCALL_WORK_EXIT is set. This includes > syscall-specific stuff like tracing and singlestep. TIF_NOTIFY_RESUME is > part of EXIT_TO_USER_MODE_WORK, handled in exit_to_user_mode_prepare(), > and isn't specific to syscall handling. Indeed. Confused myself.