From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=100.103.45.18 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1794359489; b=v3YvvymWh4icoTloyahZkRhnELw4O+GpcrABfR3qmKWj18vJT1ibATR0e4ChRMWQAz1i sfoSAwW/G6pBG0A9jTCBgKj4y9tTaorS8N6EvndkMMntcXG9F9N80JcZ6wdVOEWjXf7V0 0ibuLtUr8DNsyqcbYwKY5JUS086h9TUq8RdfdH6J0Q/MLBWf8+9uWYJErV7/+v1emz4Lv 2huv6WSHsSuECnaXEmN2eliffAEPn4MRJaHr2/VzMyptj9kicgnyMyFgJkQWOP2dtUuOH UWe4vvYKwVXocH6r9EhF0S/wTh6kI9co2zcxgO2uhg42d7fzvfBtQO1q3WTpXow1gDg== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1794359489; h=Received:DKIM-Signature:Date:Message-ID:From:To:Cc:Subject: In-Reply-To:References:MIME-Version:Content-Type: Content-Transfer-Encoding; bh=sacFON38Zqc0y3/J2tRgjPnVF2lQtxza0CfI8l1J14w=; b=QaaTq0t0TC/ZNDn0Au0hbzePBfjJYwlccx7PraD0mwG5UD7ngm7UMrAzj3EKxXWCCbf7 XFkLwmbvYpi1gWi6LSH0NhnEOI055zhqHb+yjlmD3K3It7ghIV1ainSB9S52H3E7M0u3J JnOv9ygKJfMALxtWYYGIML2QQHcbsxjKL8JnN5R576d1D0p9C8JZsqP+pyxIIQ2mu06dS dtK72Qw669M24SkLSfq2azx0obdZ5IdfnqNui3TOFQWDf7kUll0PYGXBs5HUhuDtJCXOX PXxJk22E7QfZpRhP+4Mo+xRdZsQASxbX5QRimfNA0ae16Xo3FRFe5n7NrdGlsQzbGzw== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=khPm8Q3l; arc=none smtp.remote-ip=100.103.45.18 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 35B04606A31C for ; Wed, 11 Nov 2026 01:11:29 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=khPm8Q3l Received: by smtp.kernel.org (Postfix) with ESMTPSA id DD0D41F0089F; Wed, 11 Nov 2026 01:11:28 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1794359489; bh=sacFON38Zqc0y3/J2tRgjPnVF2lQtxza0CfI8l1J14w=; h=Date:From:To:Cc:Subject:In-Reply-To:References; b=khPm8Q3l6F4l9V4rcj12Iu8e0Gak+NZZJR83Rr5qogwDtvtCmtOPxisQE0yU4d4zs uJx1sep3ZEUYayqkaZJEhVem0wZD4rJm4W/k0i+BMhH3gP3ixS9+khNvHdrkne2Tnk 6xsBAH8CRhF+Ka+f5mWRb79956wzAU1EN0phtKkX7xKH4SIcgD+1YyEXSImSKr5daL j/d90Ot9YMP2Up+WZF1rJIERAlcudbis8eATnIikfHVBXZSufMLOJhfsd35Q3rUnHx 0F1jfCUKi1oNoionkI6zwyKU0hUTu3t7XQHRkdZ1G07CnQYJ7lvDVdy9lVSYWPb98D tE0jS9RBu66Bw== Date: Tue, 10 Nov 2026 15:11:28 -1000 Message-ID: <3ac37e055b66a46f72edd235f1e93f5f@kernel.org> From: Tejun Heo To: Peter Zijlstra Cc: mingo@kernel.org, juri.lelli@redhat.com, vincent.guittot@linaro.org, dietmar.eggemann@arm.com, rostedt@goodmis.org, bsegall@google.com, mgorman@suse.de, vschneid@redhat.com, kprateek.nayak@amd.com, linux-kernel@vger.kernel.org, ziqianlu@bytedance.com Subject: Re: [PATCH v2 04/12] sched/core: Make __update_rq_clock() skip updates on UPDATED In-Reply-To: <20261107120207.126979364@infradead.org> References: <20261107115913.261163891@infradead.org> <20261107120207.126979364@infradead.org> X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Hello, Peter. On Sat, Nov 07, 2026 at 12:59:17PM +0100, Peter Zijlstra wrote: > static void __update_rq_clock(struct rq *rq) > { > + bool update; > + > lockdep_assert_rq_held(rq); > > + update = !(rq->clock_update_flags & RQCF_NOP_MASK); > rq->clock_update_flags |= RQCF_UPDATED; > > - if (!(rq->clock_update_flags & RQCF_ACT_SKIP)) { > + if (update) { RQCF_UPDATED is cleared only by rq_pin_lock() and double_rq_clock_clear_update(), so a path which takes the rq lock with raw_spin_rq_lock() inherits it from the previous holder and its update_rq_clock() is now silently skipped. Previously, you said to clear on unlock. Why not do that? That'd be less confusing overall. Thanks. -- tejun