From nobody Tue Feb 10 04:23:53 2026 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 E7388320A1A for ; Fri, 24 Oct 2025 13:26:01 +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=1761312362; cv=none; b=qdw0TFGyqAYsRxaNCOvRbVPZvTxuMEDxs5U9WNwOo6QYGxKmIme7lmV/RNw9MiquM/id4l/m2Tlp08A+UJRnC25GRfmUMKDV8T7AfJhRo6DOmAMS2Z8QRsHj/a8cBQzr/cbjmAhNTvMzJ2zXj9hoREQnOfgRxksnerA+ZwMUe/w= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1761312362; c=relaxed/simple; bh=lNiRZwtesmiFcKiHJWflQehWlUXukBZMLmjaD5n1mCc=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=FIqqgxA0nQBpCj59UA/RyrlNdxD8MYZf+3Ygixh1AHsbgjjqVKTOGLGZUCtvXBxsBkxHaLZTCM/8r4cOBYzhpU9bV6wUvvd1lCjyCT8DQcZM8riLeW6pxnUxxMfCalqnl6gg0JcKK7h2/phdW13ZPdbXF8ctrTFmbN9sh8l7Vwc= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=Q82RxeHx; 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="Q82RxeHx" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 87D59C4CEF1; Fri, 24 Oct 2025 13:26:00 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1761312361; bh=lNiRZwtesmiFcKiHJWflQehWlUXukBZMLmjaD5n1mCc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Q82RxeHxgjGxZWN16Dqhqw/nHK0LGV9qYpFai9Snpj6Z82SWY8dNfkYrhAr0qYOHe EGJ/5BfIJeKWfP3o5QXsLmkN2QAZuh2jHplSheGpTZu8uYy/S3dO+DwMiUvsELQzbn 1zwnYi+oNPbiN31KfMi2KwoBLgk/enZ2YgBbFL7xzw+ybt8QCSFh8ZOmpuT+kp8K6g 2iC1Kcc4HgiBeT8jjb+vTf+UebadGw9+EWnxkl5vmPYHHol+LOPhuIvmBMBpiKgDKe Yo34K00ptfSK3SSyGL3oGQgjLhDvWtV3RgwdCH0ZDSh3FJo3YCLRL4scxbCrNa2aT5 jLvNh8PSFzyPw== From: Frederic Weisbecker To: Thomas Gleixner Cc: LKML , Frederic Weisbecker , Anna-Maria Behnsen Subject: [PATCH 6/6] timers/migration: Remove dead code handling idle CPU checking for remote timers Date: Fri, 24 Oct 2025 15:25:36 +0200 Message-ID: <20251024132536.39841-7-frederic@kernel.org> X-Mailer: git-send-email 2.51.0 In-Reply-To: <20251024132536.39841-1-frederic@kernel.org> References: <20251024132536.39841-1-frederic@kernel.org> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" Idle migrators don't walk the whole tree in order to find out if there are timers to migrate because they recorded the next deadline to be verified within a single check in tmigr_requires_handle_remote(). Remove the related dead code and data. Signed-off-by: Frederic Weisbecker --- kernel/time/timer_migration.c | 16 ---------------- 1 file changed, 16 deletions(-) diff --git a/kernel/time/timer_migration.c b/kernel/time/timer_migration.c index 73d9b0648116..19ddfa96b9df 100644 --- a/kernel/time/timer_migration.c +++ b/kernel/time/timer_migration.c @@ -504,11 +504,6 @@ static bool tmigr_check_lonely(struct tmigr_group *gro= up) * @now: timer base monotonic * @check: is set if there is the need to handle remote timers; * required in tmigr_requires_handle_remote() only - * @tmc_active: this flag indicates, whether the CPU which triggers - * the hierarchy walk is !idle in the timer migration - * hierarchy. When the CPU is idle and the whole hierarchy is - * idle, only the first event of the top level has to be - * considered. */ struct tmigr_walk { u64 nextexp; @@ -519,7 +514,6 @@ struct tmigr_walk { unsigned long basej; u64 now; bool check; - bool tmc_active; }; =20 typedef bool (*up_f)(struct tmigr_group *, struct tmigr_group *, struct tm= igr_walk *); @@ -1119,15 +1113,6 @@ static bool tmigr_requires_handle_remote_up(struct t= migr_group *group, */ if (!tmigr_check_migrator(group, childmask)) return true; - - /* - * When there is a parent group and the CPU which triggered the - * hierarchy walk is not active, proceed the walk to reach the top level - * group before reading the next_expiry value. - */ - if (group->parent && !data->tmc_active) - return false; - /* * The lock is required on 32bit architectures to read the variable * consistently with a concurrent writer. On 64bit the lock is not @@ -1172,7 +1157,6 @@ bool tmigr_requires_handle_remote(void) data.now =3D get_jiffies_update(&jif); data.childmask =3D tmc->groupmask; data.firstexp =3D KTIME_MAX; - data.tmc_active =3D !tmc->idle; data.check =3D false; =20 /* --=20 2.51.0