From dd6414b50fa2b1cd247a8aa8f8bd42414b7453e1 Mon Sep 17 00:00:00 2001 From: Phil Carmody Date: Wed, 20 Oct 2010 15:57:33 -0700 Subject: timer: Permit statically-declared work with deferrable timers Currently, you have to just define a delayed_work uninitialised, and then initialise it before first use. That's a tad clumsy. At risk of playing mind-games with the compiler, fooling it into doing pointer arithmetic with compile-time-constants, this lets clients properly initialise delayed work with deferrable timers statically. This patch was inspired by the issues which lead Artem Bityutskiy to commit 8eab945c5616fc984 ("sunrpc: make the cache cleaner workqueue deferrable"). Signed-off-by: Phil Carmody Acked-by: Artem Bityutskiy Cc: Arjan van de Ven Signed-off-by: Andrew Morton Signed-off-by: Thomas Gleixner --- kernel/timer.c | 15 +-------------- 1 file changed, 1 insertion(+), 14 deletions(-) (limited to 'kernel') diff --git a/kernel/timer.c b/kernel/timer.c index 97bf05baade7..72853b256ff2 100644 --- a/kernel/timer.c +++ b/kernel/timer.c @@ -88,18 +88,6 @@ struct tvec_base boot_tvec_bases; EXPORT_SYMBOL(boot_tvec_bases); static DEFINE_PER_CPU(struct tvec_base *, tvec_bases) = &boot_tvec_bases; -/* - * Note that all tvec_bases are 2 byte aligned and lower bit of - * base in timer_list is guaranteed to be zero. Use the LSB to - * indicate whether the timer is deferrable. - * - * A deferrable timer will work normally when the system is busy, but - * will not cause a CPU to come out of idle just to service it; instead, - * the timer will be serviced when the CPU eventually wakes up with a - * subsequent non-deferrable timer. - */ -#define TBASE_DEFERRABLE_FLAG (0x1) - /* Functions below help us manage 'deferrable' flag */ static inline unsigned int tbase_get_deferrable(struct tvec_base *base) { @@ -113,8 +101,7 @@ static inline struct tvec_base *tbase_get_base(struct tvec_base *base) static inline void timer_set_deferrable(struct timer_list *timer) { - timer->base = ((struct tvec_base *)((unsigned long)(timer->base) | - TBASE_DEFERRABLE_FLAG)); + timer->base = TBASE_MAKE_DEFERRED(timer->base); } static inline void -- cgit v1.2.1