From c6ee36c423c3ed1fb86bb3eabba9fc256a300d16 Mon Sep 17 00:00:00 2001 From: Mike Galbraith Date: Thu, 11 Mar 2010 17:16:43 +0100 Subject: [PATCH] sched: Remove SYNC_WAKEUPS feature Sync wakeups are critical functionality with a long history. Remove it, we don't need the branch or icache footprint. Signed-off-by: Mike Galbraith Signed-off-by: Peter Zijlstra LKML-Reference: <1268301817.6785.47.camel@marge.simson.net> Signed-off-by: Ingo Molnar --- kernel/sched.c | 3 --- kernel/sched_features.h | 8 -------- 2 files changed, 11 deletions(-) diff --git a/kernel/sched.c b/kernel/sched.c index 16559de..cc6dc8c 100644 --- a/kernel/sched.c +++ b/kernel/sched.c @@ -2369,9 +2369,6 @@ static int try_to_wake_up(struct task_struct *p, unsigned int state, unsigned long flags; struct rq *rq; - if (!sched_feat(SYNC_WAKEUPS)) - wake_flags &= ~WF_SYNC; - this_cpu = get_cpu(); smp_wmb(); diff --git a/kernel/sched_features.h b/kernel/sched_features.h index 1cb7c47..f54b6f9 100644 --- a/kernel/sched_features.h +++ b/kernel/sched_features.h @@ -23,14 +23,6 @@ SCHED_FEAT(WAKEUP_PREEMPT, 1) SCHED_FEAT(ASYM_GRAN, 1) /* - * Use the SYNC wakeup hint, pipes and the likes use this to indicate - * the remote end is likely to consume the data we just wrote, and - * therefore has cache benefit from being placed on the same cpu, see - * also AFFINE_WAKEUPS. - */ -SCHED_FEAT(SYNC_WAKEUPS, 1) - -/* * Based on load and program behaviour, see if it makes sense to place * a newly woken task on the same cpu as the task that woke it -- * improve cache locality. Typically used with SYNC wakeups as -- 2.7.4