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 4008417B50A for ; Wed, 13 Aug 2025 21:32:57 +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=1755120780; cv=none; b=kd+pNoQwmv2VMKC5ZRQo+ME9QhXH6HTXNORhzzUT2eMmQ2e9IbKKuM1fgKlMpam0SOBWhQNQFXY6QH58M8sYYJtdk51L75BxxCBY4cEXx76ak/8vr6lZM6KIK/UcCAhfkW37MrhvXrZn0+j/TqGi5fZm2taD5269spMWbFFE/7s= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1755120780; c=relaxed/simple; bh=u8Pyt5wWXrSvDLFQ73CXqthEMQ5R6UrJQVV6hA8lnGw=; h=From:To:Cc:Subject:In-Reply-To:References:Date:Message-ID: MIME-Version:Content-Type; b=kq1eHorBX03fypNjndKVkCbCK9A+pj/+3B44AmyFf/Uke9DE5Zeq8XlR6ZS7xi3iOPEHd7+fNuLb0/Wsh1bv5ko/+31pK5fM4j5EtWyyLhz4+YtrW7DI5frJdMLRHfXXS3IDElgZTfpByDrse24/1pyMlwEDO4B16oC95yZprMk= 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=kixCU72p; dkim=permerror (0-bit key) header.d=linutronix.de header.i=@linutronix.de header.b=miPQTsxy; 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="kixCU72p"; dkim=permerror (0-bit key) header.d=linutronix.de header.i=@linutronix.de header.b="miPQTsxy" From: Thomas Gleixner DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1755120776; 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=F92pkFXjQnC4OZ1VICcLVkKgVuSoopvPjrfi+MtqLwk=; b=kixCU72poGCChbEXMWmlNqsBAYy4OM+H6ppQvCyT99GpG/RK2e9zpo0Qe5bD1kTwYPsj+p HwgPwGcc5EHl1yqx6kLe4tahL7l5yGIpSHqaqjbaMkUPM9ZXBTvXGh0/uaQr8/relfgsfw 1j3BJvtIk2MoOz9f3S28aUDoxEumhsWxUboSmbSyh8NuJfTpRJboZ+XjPvvTIemiazq9wZ PfgIo5fVskt9mVKa3zwHL+4TCo7KNsFtvNQ/0nW5AKLyAXuRHYEDF843tqjHmqbZCM1bmh ZSRgBO9oX7yZNdLjSbimGI2SStCJaKe6YBnM2Y8P3YRD8TPBGHZEfrfZ2/oYsA== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1755120776; 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=F92pkFXjQnC4OZ1VICcLVkKgVuSoopvPjrfi+MtqLwk=; b=miPQTsxyE++O+DeKjpIBpTZgllKO3OLAhhTA9/CUyvkuv9B29R6y+xE8kc24zuxicBDocS 2kWjkJKstFkRe9Dg== 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: <12342355-b3fb-4e78-ad5b-dcfff1366ccf@kernel.dk> References: <20250813155941.014821755@linutronix.de> <12342355-b3fb-4e78-ad5b-dcfff1366ccf@kernel.dk> Date: Wed, 13 Aug 2025 23:32:54 +0200 Message-ID: <87bjoi7vqx.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 11:45, Jens Axboe wrote: > On 8/13/25 10:29 AM, Thomas Gleixner wrote: >> >> suffered badly from the stale eventmask bits and the cleaned up version >> brought a whopping 25+% performance gain. > > Thanks for doing this work, it's been on my list to take a look at rseq > as it's quite the pig currently and enabled by default (with what I > assume is from a newer libc). Yes, recent glibc uses it. Could you give it a test ride to see whether this makes a difference in your environment? Thanks tglx