Commit 2b49ddce authored by Arnd Bergmann's avatar Arnd Bergmann
Browse files

ia64: convert to legacy_timer_tick 



ia64 is the only architecture that calls xtime_update() in a loop,
once for each jiffie that has passed since the last event.

Before commit 3171a030 ("[PATCH] simplify update_times (avoid
jiffies/jiffies_64 aliasing problem)") in 2006, it could not actually do
this any differently, but now it seems simpler to just pass the number
of jiffies that passed in the meantime.

While this loses the ability process interrupts in the middle of
the timer tick by calling local_irq_enable(), doing so is fairly
peculiar anyway and it seems better to just do what everyone
else does here.

Reviewed-by: default avatarLinus Walleij <linus.walleij@linaro.org>
Signed-off-by: default avatarArnd Bergmann <arnd@arndb.de>
parent b3550164

arch/ia64/Kconfig

+1 −0
Original line number Diff line number Diff line
@@ -46,6 +46,7 @@ config IA64 
	select ARCH_THREAD_STACK_ALLOCATOR

	select ARCH_CLOCKSOURCE_DATA

	select GENERIC_TIME_VSYSCALL

	select LEGACY_TIMER_TICK

	select SWIOTLB

	select SYSCTL_ARCH_UNALIGN_NO_WARN

	select HAVE_MOD_ARCH_SPECIFIC

arch/ia64/kernel/time.c

+13 −23
Original line number Diff line number Diff line
@@ -161,39 +161,29 @@ void vtime_account_idle(struct task_struct *tsk) 
static irqreturn_t

timer_interrupt (int irq, void *dev_id)

{

	unsigned long new_itm;

	unsigned long cur_itm, new_itm, ticks;



	if (cpu_is_offline(smp_processor_id())) {

		return IRQ_HANDLED;

	}



	new_itm = local_cpu_data->itm_next;

	cur_itm = ia64_get_itc();



	if (!time_after(ia64_get_itc(), new_itm))

	if (!time_after(cur_itm, new_itm)) {

		printk(KERN_ERR "Oops: timer tick before it's due (itc=%lx,itm=%lx)\n",

		       ia64_get_itc(), new_itm);



	profile_tick(CPU_PROFILING);



	while (1) {

		update_process_times(user_mode(get_irq_regs()));



		new_itm += local_cpu_data->itm_delta;



		if (smp_processor_id() == time_keeper_id)

			xtime_update(1);



		local_cpu_data->itm_next = new_itm;

		       cur_itm, new_itm);

		ticks = 1;

	} else {

		ticks = DIV_ROUND_UP(cur_itm - new_itm,

				     local_cpu_data->itm_delta);

		new_itm += ticks * local_cpu_data->itm_delta;

	}



		if (time_after(new_itm, ia64_get_itc()))

			break;

	if (smp_processor_id() != time_keeper_id)

		ticks = 0;



		/*

		 * Allow IPIs to interrupt the timer loop.

		 */

		local_irq_enable();

		local_irq_disable();

	}

	legacy_timer_tick(ticks);



	do {

		/*

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