From d7102e95b7b9c00277562c29aad421d2d521c5f6 Mon Sep 17 00:00:00 2001 From: "akpm@osdl.org" Date: Thu, 12 Jan 2006 01:05:32 -0800 Subject: [PATCH] sched: filter affine wakeups ) From: Nick Piggin Track the last waker CPU, and only consider wakeup-balancing if there's a match between current waker CPU and the previous waker CPU. This ensures that there is some correlation between two subsequent wakeup events before we move the task. Should help random-wakeup workloads on large SMP systems, by reducing the migration attempts by a factor of nr_cpus. Signed-off-by: Ingo Molnar Signed-off-by: Nick Piggin Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/sched.h | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) (limited to 'include/linux/sched.h') diff --git a/include/linux/sched.h b/include/linux/sched.h index 5d6b9228bba..b5ef92a043a 100644 --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -696,8 +696,11 @@ struct task_struct { int lock_depth; /* BKL lock depth */ -#if defined(CONFIG_SMP) && defined(__ARCH_WANT_UNLOCKED_CTXSW) +#if defined(CONFIG_SMP) + int last_waker_cpu; /* CPU that last woke this task up */ +#if defined(__ARCH_WANT_UNLOCKED_CTXSW) int oncpu; +#endif #endif int prio, static_prio; struct list_head run_list; -- cgit v1.2.3