From: subhra mazumdar <subhra.mazumdar@oracle.com>
To: linux-kernel@vger.kernel.org
Cc: peterz@infradead.org, mingo@redhat.com,
steven.sistare@oracle.com, dhaval.giani@oracle.com,
rohit.k.jain@oracle.com, daniel.lezcano@linaro.org
Subject: [PATCH 2/5] sched: introduce per-cpu var next_cpu to track search limit
Date: Tue, 12 Jun 2018 10:49:59 -0700 [thread overview]
Message-ID: <20180612175002.31453-3-subhra.mazumdar@oracle.com> (raw)
In-Reply-To: <20180612175002.31453-1-subhra.mazumdar@oracle.com>
Introduce a per-cpu variable to track the limit upto which idle cpu search
was done in select_idle_cpu(). This will help to start the search next time
from there. This is necessary for rotating the search window over entire
LLC domain.
Signed-off-by: subhra mazumdar <subhra.mazumdar@oracle.com>
---
kernel/sched/core.c | 2 ++
kernel/sched/sched.h | 1 +
2 files changed, 3 insertions(+)
diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index 8d59b25..b3e4ec1 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -20,6 +20,7 @@
#include <trace/events/sched.h>
DEFINE_PER_CPU_SHARED_ALIGNED(struct rq, runqueues);
+DEFINE_PER_CPU_SHARED_ALIGNED(int, next_cpu);
#if defined(CONFIG_SCHED_DEBUG) && defined(HAVE_JUMP_LABEL)
/*
@@ -5996,6 +5997,7 @@ void __init sched_init(void)
for_each_possible_cpu(i) {
struct rq *rq;
+ per_cpu(next_cpu, i) = -1;
rq = cpu_rq(i);
raw_spin_lock_init(&rq->lock);
rq->nr_running = 0;
diff --git a/kernel/sched/sched.h b/kernel/sched/sched.h
index 67702b4..eb12b50 100644
--- a/kernel/sched/sched.h
+++ b/kernel/sched/sched.h
@@ -912,6 +912,7 @@ static inline void update_idle_core(struct rq *rq) { }
#endif
DECLARE_PER_CPU_SHARED_ALIGNED(struct rq, runqueues);
+DECLARE_PER_CPU_SHARED_ALIGNED(int, next_cpu);
#define cpu_rq(cpu) (&per_cpu(runqueues, (cpu)))
#define this_rq() this_cpu_ptr(&runqueues)
--
2.9.3
next prev parent reply other threads:[~2018-06-12 17:49 UTC|newest]
Thread overview: 10+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-06-12 17:49 [RFC/RFT V2 PATCH 0/5] Improve scheduler scalability for fast path subhra mazumdar
2018-06-12 17:49 ` [PATCH 1/5] sched: limit cpu search in select_idle_cpu subhra mazumdar
2018-06-12 20:33 ` kbuild test robot
2018-06-12 22:12 ` Subhra Mazumdar
2018-06-20 7:32 ` [lkp-robot] [sched] 8dd662615c: reaim.jobs_per_min -3.3% regression kernel test robot
2018-06-12 17:49 ` subhra mazumdar [this message]
2018-06-12 17:50 ` [PATCH 3/5] sched: rotate the cpu search window for better spread subhra mazumdar
2018-06-12 17:50 ` [PATCH 4/5] sched: add sched feature to disable idle core search subhra mazumdar
2018-06-12 17:50 ` [PATCH 5/5] sched: SIS_CORE " subhra mazumdar
2018-06-28 22:44 [RESEND RFC/RFT V2 PATCH 0/5] Improve scheduler scalability for fast path subhra mazumdar
2018-06-28 22:44 ` [PATCH 2/5] sched: introduce per-cpu var next_cpu to track search limit subhra mazumdar
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