From nobody Fri Feb 13 00:13:59 2026 Received: from out-189.mta1.migadu.com (out-189.mta1.migadu.com [95.215.58.189]) (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 3DF3119AD7A for ; Wed, 5 Jun 2024 13:36:29 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=95.215.58.189 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1717594591; cv=none; b=K2sTj0w0k5CSh646wggchODVkZ+uoih6wglGh473dP3uM373kdhNTcKtwJu64rpi6IRwHb6uJVmrnUpPtxO+3ohSlwZWCy/wtsEumLufeaO7f3liFfxpGIvYEkT63s/LnAhcnmZT5drXIZeb17WqhPBWPii5sXmD8ef1o6CTlro= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1717594591; c=relaxed/simple; bh=Q+yKb3UoyyFzRRfAW+NzEGFhCqBmF4Gfe38PmpDlfNw=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=mSE12aZUQ84MUe5C31jU0nBSzq4hMC9vo/QVef5fy+BOO89wrY6h2MLAPdQ2ioLpwqtoD9B7oKEuw5XBhJUePrkknUhbXQdw1Fv9qsAYIrYaO2Ku2TrVnjOwfCR+Fwu2cUJfxOtARsxH9wo9tCUFl2zEldurMgD/nZcAcn5/UwY= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev; spf=pass smtp.mailfrom=linux.dev; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b=UfXa0Mgm; arc=none smtp.client-ip=95.215.58.189 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.dev Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b="UfXa0Mgm" X-Envelope-To: mingo@redhat.com DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1717594586; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=8yb3nN64g5IVJqtCKRjk27NnlVJOOQo5LzCqk+WIDbk=; b=UfXa0MgmXPfC5cQp4mFTQ5w4AnRjbsA95G4WA0FZbE5DR+O6chpusfCAqAbL+FuZb47rOc zpLXONsIfCQG0Klze82g5vLHVwrSOew/FU/9O5wgq2N8rZop34kYzbd36xHwEyAN7NpoBx H0w0IY0ARwcIbyTWWaIo4gSGEOgO0x0= X-Envelope-To: peterz@infradead.org X-Envelope-To: juri.lelli@redhat.com X-Envelope-To: vincent.guittot@linaro.org X-Envelope-To: dietmar.eggemann@arm.com X-Envelope-To: rostedt@goodmis.org X-Envelope-To: bsegall@google.com X-Envelope-To: mgorman@suse.de X-Envelope-To: bristot@redhat.com X-Envelope-To: vschneid@redhat.com X-Envelope-To: linux-kernel@vger.kernel.org X-Envelope-To: yajun.deng@linux.dev X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. From: Yajun Deng To: mingo@redhat.com, peterz@infradead.org, juri.lelli@redhat.com, vincent.guittot@linaro.org, dietmar.eggemann@arm.com, rostedt@goodmis.org, bsegall@google.com, mgorman@suse.de, bristot@redhat.com, vschneid@redhat.com Cc: linux-kernel@vger.kernel.org, Yajun Deng Subject: [PATCH v2 1/2] sched/rt: Use 'back' only if CONFIG_RT_GROUP_SCHED is enabled Date: Wed, 5 Jun 2024 21:35:56 +0800 Message-Id: <20240605133557.2984-2-yajun.deng@linux.dev> In-Reply-To: <20240605133557.2984-1-yajun.deng@linux.dev> References: <20240605133557.2984-1-yajun.deng@linux.dev> 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-Migadu-Flow: FLOW_OUT Content-Type: text/plain; charset="utf-8" The 'back' member in struct sched_rt_entity only related to CONFIG_RT_GROUP_SCHED, so there is no need to init it in dequeue_rt_stack. Init the 'back' member in init_tg_rt_entry and use it only if CONFIG_RT_GROUP_SCHED is enabled. Signed-off-by: Yajun Deng --- kernel/sched/rt.c | 22 ++++++++++++++++------ 1 file changed, 16 insertions(+), 6 deletions(-) diff --git a/kernel/sched/rt.c b/kernel/sched/rt.c index 63e49c8ffc4d..842a2cfd6dcc 100644 --- a/kernel/sched/rt.c +++ b/kernel/sched/rt.c @@ -230,10 +230,12 @@ void init_tg_rt_entry(struct task_group *tg, struct r= t_rq *rt_rq, if (!rt_se) return; =20 - if (!parent) + if (!parent) { rt_se->rt_rq =3D &rq->rt; - else + } else { rt_se->rt_rq =3D parent->my_q; + parent->back =3D rt_se; + } =20 rt_se->my_q =3D rt_rq; rt_se->parent =3D parent; @@ -604,6 +606,11 @@ static inline struct rt_bandwidth *sched_rt_bandwidth(= struct rt_rq *rt_rq) return &rt_rq->tg->rt_bandwidth; } =20 +static struct sched_rt_entity *rt_se_back(struct sched_rt_entity *se) +{ + return se->back; +} + #else /* !CONFIG_RT_GROUP_SCHED */ =20 static inline u64 sched_rt_runtime(struct rt_rq *rt_rq) @@ -666,6 +673,11 @@ static inline struct rt_bandwidth *sched_rt_bandwidth(= struct rt_rq *rt_rq) return &def_rt_bandwidth; } =20 +static inline struct sched_rt_entity *rt_se_back(struct sched_rt_entity *s= e) +{ + return NULL; +} + #endif /* CONFIG_RT_GROUP_SCHED */ =20 bool sched_rt_bandwidth_account(struct rt_rq *rt_rq) @@ -1428,14 +1440,12 @@ static void dequeue_rt_stack(struct sched_rt_entity= *rt_se, unsigned int flags) struct sched_rt_entity *back =3D NULL; unsigned int rt_nr_running; =20 - for_each_sched_rt_entity(rt_se) { - rt_se->back =3D back; + for_each_sched_rt_entity(rt_se) back =3D rt_se; - } =20 rt_nr_running =3D rt_rq_of_se(back)->rt_nr_running; =20 - for (rt_se =3D back; rt_se; rt_se =3D rt_se->back) { + for (rt_se =3D back; rt_se; rt_se =3D rt_se_back(rt_se)) { if (on_rt_rq(rt_se)) __dequeue_rt_entity(rt_se, flags); } --=20 2.25.1