Commit 494f6a9e authored by Christoph Lameter's avatar Christoph Lameter Committed by Tejun Heo
Browse files

this_cpu: Use this_cpu_xx in nmi handling 



this_cpu_inc/dec reduces the number of instructions needed.

Signed-off-by: default avatarChristoph Lameter <cl@linux-foundation.org>
Signed-off-by: default avatarTejun Heo <tj@kernel.org>
parent b7a4c946

arch/sparc/kernel/nmi.c

+4 −4
Original line number Diff line number Diff line
@@ -47,7 +47,7 @@ static DEFINE_PER_CPU(short, wd_enabled); 
static int endflag __initdata;



static DEFINE_PER_CPU(unsigned int, last_irq_sum);

static DEFINE_PER_CPU(local_t, alert_counter);

static DEFINE_PER_CPU(long, alert_counter);

static DEFINE_PER_CPU(int, nmi_touch);



void touch_nmi_watchdog(void)
@@ -112,13 +112,13 @@ notrace __kprobes void perfctr_irq(int irq, struct pt_regs *regs) 
		touched = 1;

	}

	if (!touched && __get_cpu_var(last_irq_sum) == sum) {

		local_inc(&__get_cpu_var(alert_counter));

		if (local_read(&__get_cpu_var(alert_counter)) == 30 * nmi_hz)

		__this_cpu_inc(per_cpu_var(alert_counter));

		if (__this_cpu_read(per_cpu_var(alert_counter)) == 30 * nmi_hz)

			die_nmi("BUG: NMI Watchdog detected LOCKUP",

				regs, panic_on_timeout);

	} else {

		__get_cpu_var(last_irq_sum) = sum;

		local_set(&__get_cpu_var(alert_counter), 0);

		__this_cpu_write(per_cpu_var(alert_counter), 0);

	}

	if (__get_cpu_var(wd_enabled)) {

		write_pic(picl_value(nmi_hz));

arch/x86/kernel/apic/nmi.c

+4 −4
Original line number Diff line number Diff line
@@ -360,7 +360,7 @@ void stop_apic_nmi_watchdog(void *unused) 
 */



static DEFINE_PER_CPU(unsigned, last_irq_sum);

static DEFINE_PER_CPU(local_t, alert_counter);

static DEFINE_PER_CPU(long, alert_counter);

static DEFINE_PER_CPU(int, nmi_touch);



void touch_nmi_watchdog(void)
@@ -437,8 +437,8 @@ nmi_watchdog_tick(struct pt_regs *regs, unsigned reason) 
		 * Ayiee, looks like this CPU is stuck ...

		 * wait a few IRQs (5 seconds) before doing the oops ...

		 */

		local_inc(&__get_cpu_var(alert_counter));

		if (local_read(&__get_cpu_var(alert_counter)) == 5 * nmi_hz)

		__this_cpu_inc(per_cpu_var(alert_counter));

		if (__this_cpu_read(per_cpu_var(alert_counter)) == 5 * nmi_hz)

			/*

			 * die_nmi will return ONLY if NOTIFY_STOP happens..

			 */
@@ -446,7 +446,7 @@ nmi_watchdog_tick(struct pt_regs *regs, unsigned reason) 
				regs, panic_on_timeout);

	} else {

		__get_cpu_var(last_irq_sum) = sum;

		local_set(&__get_cpu_var(alert_counter), 0);

		__this_cpu_write(per_cpu_var(alert_counter), 0);

	}



	/* see if the nmi watchdog went off */