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 4F41F2F2D; Tue, 27 Feb 2024 13:44:12 +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=1709041452; cv=none; b=QxWzoMP7QhKp21WV8P+Fx4cDNJRaI5bQIHpc3zFDEfkWLeFclTUXS5gGGbh8/YqeTsfNyJi7fPvnktvnlCJo+k+7DnGsonGUobTkXoKgWfg/2v+oz9N/dm0C3zVhed9av9XWw6bCc8NNLyumlPJcCXx1mQ1Yf04v5sl9rKauCrI= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1709041452; c=relaxed/simple; bh=iQ8Wodz4oFKhAJFuy0ZujvH83AHamVrSr2e5E3q1G2Q=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=QkcuSdGHuI73orByOkBbec3a4X6qV2hAJw8uN0RcHt2AoheMukZAn6009y67LXCHrbJLoZOnDQui4WfT9vaF+pSA++YcH24FT7sAR7hzz5XTEiTX2mRqTyRI/Ioa/sJZPCmzmMAVf6IbK/3a1esEnU5xwI8yzD2kzf7c4Iby/ho= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=hyr0n8Aq; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="hyr0n8Aq" Received: by smtp.kernel.org (Postfix) with ESMTPSA id CFCC0C433F1; Tue, 27 Feb 2024 13:44:11 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1709041452; bh=iQ8Wodz4oFKhAJFuy0ZujvH83AHamVrSr2e5E3q1G2Q=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=hyr0n8AqE54jVly48elaIuokdLhYLiOj3u4mJ/H2QJxrxr80xuYbrfCU+oyoxisHG dtOvk0xXl8K+b1WvGUB77flj7U5V3c0Reya6aBYscq1vQPQzTh4At0EFYzL2dlqrX8 3Fpk3zYQAD/1mJQAUXNN924FOYd1ji0GBcdW8fIc= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Cyril Hrubis , "Peter Zijlstra (Intel)" , Petr Vorel , Mel Gorman Subject: [PATCH 4.19 10/52] sched/rt: sysctl_sched_rr_timeslice show default timeslice after reset Date: Tue, 27 Feb 2024 14:25:57 +0100 Message-ID: <20240227131548.871065821@linuxfoundation.org> X-Mailer: git-send-email 2.44.0 In-Reply-To: <20240227131548.514622258@linuxfoundation.org> References: <20240227131548.514622258@linuxfoundation.org> User-Agent: quilt/0.67 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 4.19-stable review patch. If anyone has any objections, please let me know. ------------------ From: Cyril Hrubis [ Upstream commit c1fc6484e1fb7cc2481d169bfef129a1b0676abe ] The sched_rr_timeslice can be reset to default by writing value that is <= 0. However after reading from this file we always got the last value written, which is not useful at all. $ echo -1 > /proc/sys/kernel/sched_rr_timeslice_ms $ cat /proc/sys/kernel/sched_rr_timeslice_ms -1 Fix this by setting the variable that holds the sysctl file value to the jiffies_to_msecs(RR_TIMESLICE) in case that <= 0 value was written. Signed-off-by: Cyril Hrubis Signed-off-by: Peter Zijlstra (Intel) Reviewed-by: Petr Vorel Acked-by: Mel Gorman Tested-by: Petr Vorel Link: https://lore.kernel.org/r/20230802151906.25258-3-chrubis@suse.cz Signed-off-by: Petr Vorel Signed-off-by: Greg Kroah-Hartman --- kernel/sched/rt.c | 3 +++ 1 file changed, 3 insertions(+) --- a/kernel/sched/rt.c +++ b/kernel/sched/rt.c @@ -2735,6 +2735,9 @@ int sched_rr_handler(struct ctl_table *t sched_rr_timeslice = sysctl_sched_rr_timeslice <= 0 ? RR_TIMESLICE : msecs_to_jiffies(sysctl_sched_rr_timeslice); + + if (sysctl_sched_rr_timeslice <= 0) + sysctl_sched_rr_timeslice = jiffies_to_msecs(RR_TIMESLICE); } mutex_unlock(&mutex);