From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 886E523FC49 for ; Sat, 29 Nov 2025 17:43:25 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1764438205; cv=none; b=AIVsstJ01rDHRxq5NiBCLxzVA3IlcBd/LGZPDI85QBBS1YxicE5y72LzG2ELzc1Yhy5UYKbw8/2OkKnn6d/WSjQLxLdIW7+CXmbfBXlYq/inqJHo7bYE3gb/6mvLWTWgzPCp4ym5CKjXibyK8oCtEyV4aQpRkPnaFwyO+ONO/aI= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1764438205; c=relaxed/simple; bh=JcnwlmTnsS1yB5aZtQ4ptZKTLUwEnxFTflgGb3Gvf+o=; h=Content-Type:MIME-Version:Subject:From:Message-Id:Date:References: In-Reply-To:To:Cc; b=USK1+v28ZwqbCsEL2ti93K7oVkP8VQ9aPjzBYzRP2NazjiSRpxIyEmz93XinsbaSs+qzM7dviG64bQiDliuEVGg8204LctlJLXJPLgFUI4i1dZPKW6Thhzc1BNA3BSH45xviLFEgVK01SYUBRbeGJQSfVbn6ECwPC3HSgYFPydM= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=GVFLogRu; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="GVFLogRu" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 04FC0C4CEF7; Sat, 29 Nov 2025 17:43:25 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1764438205; bh=JcnwlmTnsS1yB5aZtQ4ptZKTLUwEnxFTflgGb3Gvf+o=; h=Subject:From:Date:References:In-Reply-To:To:Cc:From; b=GVFLogRu/xa5guCaVLILAQzgZZb/OM4KaB7xNiHTpdlxvUt7PqTWPGor4RfXGJ3Sv /pJVORFxrJfMe95ZWfko9zr9eu7JsoT+wEWD2C+txRu9S3rTvSzy476TcgheorYE0W w/rK0zCOwvtpCyPKEj6fmXut1A0qjxoOlmUXMmILqeRpw7++oRqQnlli1UFm5lvo6j wlQJoOQm+cl4NN80qh/M1jbN3L/X0zxEouBsDQuSKI12Cibp11mZensZP0u6Onmza2 si9MYj1WbUc4v7SQVYTwNZrsVVpR7DYtN+1r53vpqPbPrJRk1oBwANeI4rUpLr6HLo AAkvcLn128p9w== Received: from [10.30.226.235] (localhost [IPv6:::1]) by aws-us-west-2-korg-oddjob-rhel9-1.codeaurora.org (Postfix) with ESMTP id 789D23806934; Sat, 29 Nov 2025 17:40:27 +0000 (UTC) Content-Type: text/plain; charset="utf-8" Precedence: bulk X-Mailing-List: bpf@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Subject: Re: [PATCH bpf-next v2 0/6] Limited queueing in NMI for rqspinlock From: patchwork-bot+netdevbpf@kernel.org Message-Id: <176443802605.1058790.42854168580684799.git-patchwork-notify@kernel.org> Date: Sat, 29 Nov 2025 17:40:26 +0000 References: <20251128232802.1031906-1-memxor@gmail.com> In-Reply-To: <20251128232802.1031906-1-memxor@gmail.com> To: Kumar Kartikeya Dwivedi Cc: bpf@vger.kernel.org, ast@kernel.org, andrii@kernel.org, daniel@iogearbox.net, martin.lau@kernel.org, eddyz87@gmail.com, ritesh@superluminal.eu, jelle@superluminal.eu, kkd@meta.com, kernel-team@meta.com Hello: This series was applied to bpf/bpf-next.git (master) by Alexei Starovoitov : On Fri, 28 Nov 2025 23:27:56 +0000 you wrote: > Ritesh reported that he was frequently seeing timeouts in cases which > should have been covered by the AA heuristics. This led to the discovery > of multiple gaps in the current code that could lead to timeouts when > AA heuristics could work to prevent them. More details and investigation > is available in the original threads. [0][1] > > This set restores the ability for NMI waiters to queue in the slow path, > and reduces the cases where they would attempt to trylock. However, such > queueing must not happen when interrupting waiters which the NMI itself > depends upon for forward progress; in those cases the trylock fallback > remains, but with a single attempt to avoid aimless attempts to acquire > the lock. > > [...] Here is the summary with links: - [bpf-next,v2,1/6] rqspinlock: Enclose lock/unlock within lock entry acquisitions https://git.kernel.org/bpf/bpf-next/c/beb7021a6003 - [bpf-next,v2,2/6] rqspinlock: Perform AA checks immediately https://git.kernel.org/bpf/bpf-next/c/5860f5ce479f - [bpf-next,v2,3/6] rqspinlock: Use trylock fallback when per-CPU rqnode is busy https://git.kernel.org/bpf/bpf-next/c/81d5a6a43859 - [bpf-next,v2,4/6] rqspinlock: Disable spinning for trylock fallback https://git.kernel.org/bpf/bpf-next/c/30dc2f7025fe - [bpf-next,v2,5/6] rqspinlock: Precede non-head waiter queueing with AA check https://git.kernel.org/bpf/bpf-next/c/087849cca31d - [bpf-next,v2,6/6] selftests/bpf: Add success stats to rqspinlock stress test https://git.kernel.org/bpf/bpf-next/c/3448375e71a4 You are awesome, thank you! -- Deet-doot-dot, I am a bot. https://korg.docs.kernel.org/patchwork/pwbot.html