From: Dietmar Eggemann Date: Mon, 22 Aug 2016 14:00:41 +0000 (+0100) Subject: sched/fair: Fix fixed point arithmetic width for shares and effective load X-Git-Tag: v4.14-rc1~2409^2~21 X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=ab522e33f91799661aad47bebb691f241a9f6bb8;p=platform%2Fkernel%2Flinux-rpi.git sched/fair: Fix fixed point arithmetic width for shares and effective load Since commit: 2159197d6677 ("sched/core: Enable increased load resolution on 64-bit kernels") we now have two different fixed point units for load: - 'shares' in calc_cfs_shares() has 20 bit fixed point unit on 64-bit kernels. Therefore use scale_load() on MIN_SHARES. - 'wl' in effective_load() has 10 bit fixed point unit. Therefore use scale_load_down() on tg->shares which has 20 bit fixed point unit on 64-bit kernels. Signed-off-by: Dietmar Eggemann Signed-off-by: Peter Zijlstra (Intel) Cc: Linus Torvalds Cc: Mike Galbraith Cc: Peter Zijlstra Cc: Thomas Gleixner Link: http://lkml.kernel.org/r/1471874441-24701-1-git-send-email-dietmar.eggemann@arm.com Signed-off-by: Ingo Molnar --- diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c index 8fb4d19..786ef94 100644 --- a/kernel/sched/fair.c +++ b/kernel/sched/fair.c @@ -5017,9 +5017,9 @@ static long effective_load(struct task_group *tg, int cpu, long wl, long wg) * wl = S * s'_i; see (2) */ if (W > 0 && w < W) - wl = (w * (long)tg->shares) / W; + wl = (w * (long)scale_load_down(tg->shares)) / W; else - wl = tg->shares; + wl = scale_load_down(tg->shares); /* * Per the above, wl is the new se->load.weight value; since