Commit 17770579 authored by Valentin Schneider's avatar Valentin Schneider Committed by Peter Zijlstra
Browse files

sched: Add WF_TTWU, WF_EXEC wakeup flags 



To remove the sd_flag parameter of select_task_rq(), we need another way of
encoding wakeup types. There already is a WF_FORK flag, add the missing two.

With that said, we still need an easy way to turn WF_foo into
SD_bar (e.g. WF_TTWU into SD_BALANCE_WAKE). As suggested by Peter, let's
make our lives easier and make them match exactly, and throw in some
compile-time checks for good measure.

Signed-off-by: default avatarValentin Schneider <valentin.schneider@arm.com>
Signed-off-by: default avatarPeter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20201102184514.2733-2-valentin.schneider@arm.com
parent cdb31047

kernel/sched/sched.h

+14 −7
Original line number Diff line number Diff line
@@ -1744,13 +1744,20 @@ static inline int task_on_rq_migrating(struct task_struct *p) 
	return READ_ONCE(p->on_rq) == TASK_ON_RQ_MIGRATING;

}



/*

 * wake flags

 */

#define WF_SYNC			0x01		/* Waker goes to sleep after wakeup */

#define WF_FORK			0x02		/* Child wakeup after fork */

#define WF_MIGRATED		0x04		/* Internal use, task got migrated */

#define WF_ON_CPU		0x08		/* Wakee is on_cpu */

/* Wake flags. The first three directly map to some SD flag value */

#define WF_EXEC     0x02 /* Wakeup after exec; maps to SD_BALANCE_EXEC */

#define WF_FORK     0x04 /* Wakeup after fork; maps to SD_BALANCE_FORK */

#define WF_TTWU     0x08 /* Wakeup;            maps to SD_BALANCE_WAKE */



#define WF_SYNC     0x10 /* Waker goes to sleep after wakeup */

#define WF_MIGRATED 0x20 /* Internal use, task got migrated */

#define WF_ON_CPU   0x40 /* Wakee is on_cpu */



#ifdef CONFIG_SMP

static_assert(WF_EXEC == SD_BALANCE_EXEC);

static_assert(WF_FORK == SD_BALANCE_FORK);

static_assert(WF_TTWU == SD_BALANCE_WAKE);

#endif



/*

 * To aid in avoiding the subversion of "niceness" due to uneven distribution