Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 1aabd67d authored by Torben Hohn's avatar Torben Hohn Committed by Thomas Gleixner
Browse files

ia64: Switch do_timer() to xtime_update() 



local_cpu_data->itm_next = new_itm; does not need to be protected by
xtime_lock. xtime_update() takes the lock itself.

Signed-off-by: default avatarTorben Hohn <torbenh@gmx.de>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: johnstul@us.ibm.com
Cc: hch@infradead.org
Cc: yong.zhang0@gmail.com
LKML-Reference: <20110127145956.23248.49107.stgit@localhost>
Signed-off-by: default avatarThomas Gleixner <tglx@linutronix.de>
parent daad8b58

arch/ia64/kernel/time.c

+5 −14
Original line number Original line Diff line number Diff line
@@ -190,18 +190,9 @@ timer_interrupt (int irq, void *dev_id) 




		new_itm += local_cpu_data->itm_delta;

		new_itm += local_cpu_data->itm_delta;





		if (smp_processor_id() == time_keeper_id) {

		if (smp_processor_id() == time_keeper_id)

			/*

			xtime_update(1);

			 * Here we are in the timer irq handler. We have irqs locally



			 * disabled, but we don't know if the timer_bh is running on

			 * another CPU. We need to avoid to SMP race by acquiring the

			 * xtime_lock.

			 */

			write_seqlock(&xtime_lock);

			do_timer(1);

			local_cpu_data->itm_next = new_itm;

			write_sequnlock(&xtime_lock);

		} else

		local_cpu_data->itm_next = new_itm;

		local_cpu_data->itm_next = new_itm;





		if (time_after(new_itm, ia64_get_itc()))

		if (time_after(new_itm, ia64_get_itc()))
@@ -222,7 +213,7 @@ timer_interrupt (int irq, void *dev_id) 
		 * comfort, we increase the safety margin by

		 * comfort, we increase the safety margin by

		 * intentionally dropping the next tick(s).  We do NOT

		 * intentionally dropping the next tick(s).  We do NOT

		 * update itm.next because that would force us to call

		 * update itm.next because that would force us to call

		 * do_timer() which in turn would let our clock run

		 * xtime_update() which in turn would let our clock run

		 * too fast (with the potentially devastating effect

		 * too fast (with the potentially devastating effect

		 * of losing monotony of time).

		 * of losing monotony of time).

		 */

		 */

arch/ia64/xen/time.c

+5 −8
Original line number Original line Diff line number Diff line
@@ -139,14 +139,11 @@ consider_steal_time(unsigned long new_itm) 
		run_posix_cpu_timers(p);

		run_posix_cpu_timers(p);

		delta_itm += local_cpu_data->itm_delta * (stolen + blocked);

		delta_itm += local_cpu_data->itm_delta * (stolen + blocked);





		if (cpu == time_keeper_id) {

		if (cpu == time_keeper_id)

			write_seqlock(&xtime_lock);

			xtime_update(stolen + blocked);

			do_timer(stolen + blocked);



			local_cpu_data->itm_next = delta_itm + new_itm;

			write_sequnlock(&xtime_lock);

		} else {

		local_cpu_data->itm_next = delta_itm + new_itm;

		local_cpu_data->itm_next = delta_itm + new_itm;

		}



		per_cpu(xen_stolen_time, cpu) += NS_PER_TICK * stolen;

		per_cpu(xen_stolen_time, cpu) += NS_PER_TICK * stolen;

		per_cpu(xen_blocked_time, cpu) += NS_PER_TICK * blocked;

		per_cpu(xen_blocked_time, cpu) += NS_PER_TICK * blocked;

	}

	}