From nobody Sat Feb 14 07:05:25 2026 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) (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 842D65A110 for ; Wed, 15 May 2024 13:37:11 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=170.10.129.124 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1715780233; cv=none; b=uzwxYn1EVgb0atd46/x/hv+PejEELljFsQOcXl9Y4GxPpURB/kKvgN5ju+36yj4NT/aePijWlKo3Yr222qUEf9s4ViecTuRMKJaq094zIPY0PikfzzL2h6u1wgEMolryp0/2cPg4hNZy/gsAhGo2gfu+7DGNW8lfpmomevgBkjI= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1715780233; c=relaxed/simple; bh=RsqRRc6Wt+CMqhSQLy6K6PVMEVgsI4eCqXnrxOJ6uCU=; h=From:To:Cc:Subject:Date:Message-Id:MIME-Version:Content-type; b=Y98WoQbtwxv9rcfNiJHii3CI+lvVa2mfp7sE7JYO00iWc8idP7jTX4kqtyVC85boFzynMDxhlSUvgGp+yY61zgblYuA1+DEZVovVVG6YTIm3E0lMQT3+paP/TIe/+PPeH2BI8sCXDPOP375dZ5tlgL3bOt8HZ/rdU6mB5ossrAE= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=redhat.com; spf=pass smtp.mailfrom=redhat.com; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b=UjsGcw/6; arc=none smtp.client-ip=170.10.129.124 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=redhat.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=redhat.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="UjsGcw/6" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1715780230; 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: content-transfer-encoding:content-transfer-encoding; bh=UgKDKXX7vsPnb3EIpMpZvDmyXxGDZTOySnWlU80+dwU=; b=UjsGcw/67rgiVfLjJ7B7OJUdXCLnSbgy6DqQLtwuAqSJrFcEGtHVcOdItn5DBg0Cumggaz 1AaGsiY62ONb3tyKUH5lqUZqgpITDAi97BJCvPCmaf7hTbaJtNof4EFLS34fMspwLQD6Fo ScsF82YCy9LIGUynNWjvLtz1XeJ6gc8= Received: from mimecast-mx02.redhat.com (mx-ext.redhat.com [66.187.233.73]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-163-YkdP7gDoM2GwaVBRzoLv8A-1; Wed, 15 May 2024 09:37:07 -0400 X-MC-Unique: YkdP7gDoM2GwaVBRzoLv8A-1 Received: from smtp.corp.redhat.com (int-mx04.intmail.prod.int.rdu2.redhat.com [10.11.54.4]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 8A86A29AA399; Wed, 15 May 2024 13:37:06 +0000 (UTC) Received: from pauld.bos.com (dhcp-17-223.bos.redhat.com [10.18.17.223]) by smtp.corp.redhat.com (Postfix) with ESMTP id 1A0712026D68; Wed, 15 May 2024 13:37:06 +0000 (UTC) From: Phil Auld To: linux-kernel@vger.kernel.org Cc: Peter Zijlstra , Ingo Molnar , Vincent Guittot , Ben Segall , Juri Lelli , Valentin Schneider Subject: [PATCH] sched: remove HZ_BW feature hedge Date: Wed, 15 May 2024 09:37:05 -0400 Message-Id: <20240515133705.3632915-1-pauld@redhat.com> 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 X-Scanned-By: MIMEDefang 3.4.1 on 10.11.54.4 Content-Type: text/plain; charset="utf-8" As a hedge against unexpected user issues commit 88c56cfeaec4 ("sched/fair: Block nohz tick_stop when cfs bandwidth in use") included a scheduler feature to disable the new functionality. It's been a few releases (v6.6) and no screams, so remove it. Signed-off-by: Phil Auld Cc: Peter Zijlstra (Intel) Cc: Ingo Molnar Cc: Vincent Guittot Cc: Juri Lelli Cc: Ben Segall Cc: Valentin Schneider Reviewed-by: Valentin Schneider --- kernel/sched/core.c | 2 +- kernel/sched/fair.c | 2 +- kernel/sched/features.h | 2 -- 3 files changed, 2 insertions(+), 4 deletions(-) diff --git a/kernel/sched/core.c b/kernel/sched/core.c index 7019a40457a6..d7afcee8e2ae 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -1269,7 +1269,7 @@ bool sched_can_stop_tick(struct rq *rq) * dequeued by migrating while the constrained task continues to run. * E.g. going from 2->1 without going through pick_next_task(). */ - if (sched_feat(HZ_BW) && __need_bw_check(rq, rq->curr)) { + if (__need_bw_check(rq, rq->curr)) { if (cfs_task_bw_constrained(rq->curr)) return false; } diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c index c62805dbd608..06e026f10cb4 100644 --- a/kernel/sched/fair.c +++ b/kernel/sched/fair.c @@ -6549,7 +6549,7 @@ static void sched_fair_update_stop_tick(struct rq *rq= , struct task_struct *p) { int cpu =3D cpu_of(rq); =20 - if (!sched_feat(HZ_BW) || !cfs_bandwidth_used()) + if (!cfs_bandwidth_used()) return; =20 if (!tick_nohz_full_cpu(cpu)) diff --git a/kernel/sched/features.h b/kernel/sched/features.h index 143f55df890b..929021fd6bc4 100644 --- a/kernel/sched/features.h +++ b/kernel/sched/features.h @@ -85,5 +85,3 @@ SCHED_FEAT(WA_BIAS, true) SCHED_FEAT(UTIL_EST, true) =20 SCHED_FEAT(LATENCY_WARN, false) - -SCHED_FEAT(HZ_BW, true) --=20 2.39.3