Messages in this thread | | | From | Paul Turner <> | Date | Mon, 10 Jan 2011 15:49:21 -0800 | Subject | Re: [patch 1/2] sched: move periodic share updates to entity_tick() |
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Back from the Holidays and catching up on email -- Peter, looks like this fix still needs merging?
On Thu, Dec 16, 2010 at 6:26 AM, Mike Galbraith <efault@gmx.de> wrote: > On Thu, 2010-12-16 at 12:03 +0100, Peter Zijlstra wrote: >> I made that: > > Box is ill, I'll test these as soon as it's all better. > >> --- >> Subject: sched: Move periodic share updates to entity_tick() >> From: Paul Turner <pjt@google.com> >> Date: Wed, 15 Dec 2010 19:10:17 -0800 >> >> Long running entities that do not block (dequeue) require periodic updates to >> maintain accurate share values. (Note: group entities with several threads are >> quite likely to be non-blocking in many circumstances). >> >> By virtue of being long-running however, we will see entity ticks (otherwise >> the required update occurs in dequeue/put and we are done). Thus we can move >> the detection (and associated work) for these updates into the periodic path. >> >> This restores the 'atomicity' of update_curr() with respect to accounting. >> >> Signed-off-by: Paul Turner <pjt@google.com> >> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> >> LKML-Reference: <20101216031038.067028969@google.com> >> --- >> kernel/sched_fair.c | 21 +++++++++++++++++---- >> 1 file changed, 17 insertions(+), 4 deletions(-) >> >> Index: linux-2.6/kernel/sched_fair.c >> =================================================================== >> --- linux-2.6.orig/kernel/sched_fair.c >> +++ linux-2.6/kernel/sched_fair.c >> @@ -564,10 +564,6 @@ __update_curr(struct cfs_rq *cfs_rq, str >> >> #if defined CONFIG_SMP && defined CONFIG_FAIR_GROUP_SCHED >> cfs_rq->load_unacc_exec_time += delta_exec; >> - if (cfs_rq->load_unacc_exec_time > sysctl_sched_shares_window) { >> - update_cfs_load(cfs_rq, 0); >> - update_cfs_shares(cfs_rq, 0); >> - } >> #endif >> } >> >> @@ -809,6 +805,14 @@ static void update_cfs_shares(struct cfs >> >> reweight_entity(cfs_rq_of(se), se, shares); >> } >> + >> +static void update_entity_shares_tick(struct cfs_rq *cfs_rq) >> +{ >> + if (cfs_rq->load_unacc_exec_time > sysctl_sched_shares_window) { >> + update_cfs_load(cfs_rq, 0); >> + update_cfs_shares(cfs_rq, 0); >> + } >> +} >> #else /* CONFIG_FAIR_GROUP_SCHED */ >> static void update_cfs_load(struct cfs_rq *cfs_rq, int global_update) >> { >> @@ -817,6 +821,10 @@ static void update_cfs_load(struct cfs_r >> static inline void update_cfs_shares(struct cfs_rq *cfs_rq, long weight_delta) >> { >> } >> + >> +static inline void update_entity_shares_tick(struct cfs_rq *cfs_rq) >> +{ >> +} >> #endif /* CONFIG_FAIR_GROUP_SCHED */ >> >> static void enqueue_sleeper(struct cfs_rq *cfs_rq, struct sched_entity *se) >> @@ -1133,6 +1141,11 @@ entity_tick(struct cfs_rq *cfs_rq, struc >> */ >> update_curr(cfs_rq); >> >> + /* >> + * Update share accounting for long-running entities. >> + */ >> + update_entity_shares_tick(cfs_rq); >> + >> #ifdef CONFIG_SCHED_HRTICK >> /* >> * queued ticks are scheduled to match the slice, so don't bother >> > > > -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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