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 1D0D72EA743 for ; Wed, 13 Aug 2025 22:08:36 +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=1755122918; cv=none; b=V102L2dyNCBuFNrRuBqplvdpA32uVHSj+44H+RSkGvCxJ0WT9haa/15i3EaMnjwLy4aU6mGlYuFsdq17njY+m5d53fKBtfC2ZGX/WfSsiXOiFiDFJ5THp65jRSQ09mFDZ3eDp99WFE57p/ZKH39wVcPnPUOImioErLcbyt17rV8= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1755122918; c=relaxed/simple; bh=OaYM3obHKZ/CPH+P9kky35KoETEEifJP9rYw9CIY8e8=; h=From:To:Cc:Subject:In-Reply-To:References:Date:Message-ID: MIME-Version:Content-Type; b=Uwxc9vijIfPNmbNQnBvBwV6WywGuh4B3MZ4MvdOQxJuWaeKKPtXtlrWVxHSohPVNKsrKjFtpKcijRVkWKLIy4+P+/g1WuYKo8b0smNY8UOemVegoiw91wmAhkQ63f0h4b71GUQamLsK432WqfXBwoecIPkJug5+GoUg+4u5xXqI= 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=qyRgJpH0; dkim=permerror (0-bit key) header.d=linutronix.de header.i=@linutronix.de header.b=BAt7ut8g; 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="qyRgJpH0"; dkim=permerror (0-bit key) header.d=linutronix.de header.i=@linutronix.de header.b="BAt7ut8g" From: Thomas Gleixner DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1755122913; 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=6bnrhmTejItkeo982JeGsxifcGLJ0XQov0JrW3C+OCc=; b=qyRgJpH0XAbnIIa2QkcQoBYYiJWy74pCpGldBnRkfvQ8BrVDfvN6nHAE+3pscME0B24ySa szSNWgBy1jFF/EGYXtTaPEgLkq/61RJ8y8Km3GKECTnSWgUMsYDjAwExc3nEWfsgVdHmLT 0Nt9JBBpvKBL6ODr6WzOfyIFsCoQQabGUg7g8msZYrD0tLztT9oYsMsUSXTHqO0wx+6w9+ ns0rUDePUPu681kYD53gG541vu3tl5e0eygr0WNlZZysgFapGqxEa0+ppBYZpmpmhwEldz SpycTCGXrKoxmxxfcIeAN55HQ+EXHiYOdZ14LfPvWOGuqAifj4aCWhyxqI2vMQ== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1755122913; 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=6bnrhmTejItkeo982JeGsxifcGLJ0XQov0JrW3C+OCc=; b=BAt7ut8gymE5SGEPuFbkDwgW+VUTsawug9Z+lk8qnng1LxWreD/FjHdPMCpAvJHCnnbI+1 itfGyrzCLO9LGaCA== To: Jens Axboe , LKML Cc: Michael Jeanson , Mathieu Desnoyers , Peter Zijlstra , "Paul E. McKenney" , Boqun Feng , Wei Liu Subject: Re: [patch 00/11] rseq: Optimize exit to user space In-Reply-To: <6b428c1f-4118-4ede-8674-eceee96036c1@kernel.dk> References: <20250813155941.014821755@linutronix.de> <12342355-b3fb-4e78-ad5b-dcfff1366ccf@kernel.dk> <87bjoi7vqx.ffs@tglx> <6b428c1f-4118-4ede-8674-eceee96036c1@kernel.dk> Date: Thu, 14 Aug 2025 00:08:32 +0200 Message-ID: <877bz67u3j.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 Wed, Aug 13 2025 at 15:36, Jens Axboe wrote: > On 8/13/25 3:32 PM, Thomas Gleixner wrote: >> Could you give it a test ride to see whether this makes a difference in >> your environment? > > Yep, I'll give a spin. Appreciated. > If I recall correct, I'd see rseq at 2-3% of overall CPU time last I I'm not surprised. > tested. I'll try and do some pre/post numbers for some of the stuff I > usually run. Cool. Thanks tglx