Commit 46c30311 authored by Sven Schnelle's avatar Sven Schnelle Committed by Vasily Gorbik
Browse files

s390/vtime: Remove duplicate get_lowcore() calls 



Assign the output from get_lowcore() to a local variable,
so the code is easier to read.

Acked-by: default avatarHeiko Carstens <hca@linux.ibm.com>
Signed-off-by: default avatarSven Schnelle <svens@linux.ibm.com>
Signed-off-by: default avatarVasily Gorbik <gor@linux.ibm.com>
parent eb28ec2b

arch/s390/include/asm/vtime.h

+10 −6
Original line number Diff line number Diff line
@@ -4,16 +4,20 @@ 


static inline void update_timer_sys(void)

{

	get_lowcore()->system_timer += get_lowcore()->last_update_timer - get_lowcore()->exit_timer;

	get_lowcore()->user_timer += get_lowcore()->exit_timer - get_lowcore()->sys_enter_timer;

	get_lowcore()->last_update_timer = get_lowcore()->sys_enter_timer;

	struct lowcore *lc = get_lowcore();



	lc->system_timer += lc->last_update_timer - lc->exit_timer;

	lc->user_timer += lc->exit_timer - lc->sys_enter_timer;

	lc->last_update_timer = lc->sys_enter_timer;

}



static inline void update_timer_mcck(void)

{

	get_lowcore()->system_timer += get_lowcore()->last_update_timer - get_lowcore()->exit_timer;

	get_lowcore()->user_timer += get_lowcore()->exit_timer - get_lowcore()->mcck_enter_timer;

	get_lowcore()->last_update_timer = get_lowcore()->mcck_enter_timer;

	struct lowcore *lc = get_lowcore();



	lc->system_timer += lc->last_update_timer - lc->exit_timer;

	lc->user_timer += lc->exit_timer - lc->mcck_enter_timer;

	lc->last_update_timer = lc->mcck_enter_timer;

}



#endif /* _S390_VTIME_H */

arch/s390/kernel/vtime.c

+42 −36
Original line number Diff line number Diff line
@@ -35,14 +35,15 @@ static DEFINE_PER_CPU(u64, mt_scaling_jiffies); 


static inline void set_vtimer(u64 expires)

{

	struct lowcore *lc = get_lowcore();

	u64 timer;



	asm volatile(

		"	stpt	%0\n"	/* Store current cpu timer value */

		"	spt	%1"	/* Set new value imm. afterwards */

		: "=Q" (timer) : "Q" (expires));

	get_lowcore()->system_timer += get_lowcore()->last_update_timer - timer;

	get_lowcore()->last_update_timer = expires;

	lc->system_timer += lc->last_update_timer - timer;

	lc->last_update_timer = expires;

}



static inline int virt_timer_forward(u64 elapsed)
@@ -117,22 +118,23 @@ static void account_system_index_scaled(struct task_struct *p, u64 cputime, 
static int do_account_vtime(struct task_struct *tsk)

{

	u64 timer, clock, user, guest, system, hardirq, softirq;

	struct lowcore *lc = get_lowcore();



	timer = get_lowcore()->last_update_timer;

	clock = get_lowcore()->last_update_clock;

	timer = lc->last_update_timer;

	clock = lc->last_update_clock;

	asm volatile(

		"	stpt	%0\n"	/* Store current cpu timer value */

		"	stckf	%1"	/* Store current tod clock value */

		: "=Q" (get_lowcore()->last_update_timer),

		  "=Q" (get_lowcore()->last_update_clock)

		: "=Q" (lc->last_update_timer),

		  "=Q" (lc->last_update_clock)

		: : "cc");

	clock = get_lowcore()->last_update_clock - clock;

	timer -= get_lowcore()->last_update_timer;

	clock = lc->last_update_clock - clock;

	timer -= lc->last_update_timer;



	if (hardirq_count())

		get_lowcore()->hardirq_timer += timer;

		lc->hardirq_timer += timer;

	else

		get_lowcore()->system_timer += timer;

		lc->system_timer += timer;



	/* Update MT utilization calculation */

	if (smp_cpu_mtid &&
@@ -141,16 +143,16 @@ static int do_account_vtime(struct task_struct *tsk) 


	/* Calculate cputime delta */

	user = update_tsk_timer(&tsk->thread.user_timer,

				READ_ONCE(get_lowcore()->user_timer));

				READ_ONCE(lc->user_timer));

	guest = update_tsk_timer(&tsk->thread.guest_timer,

				 READ_ONCE(get_lowcore()->guest_timer));

				 READ_ONCE(lc->guest_timer));

	system = update_tsk_timer(&tsk->thread.system_timer,

				  READ_ONCE(get_lowcore()->system_timer));

				  READ_ONCE(lc->system_timer));

	hardirq = update_tsk_timer(&tsk->thread.hardirq_timer,

				   READ_ONCE(get_lowcore()->hardirq_timer));

				   READ_ONCE(lc->hardirq_timer));

	softirq = update_tsk_timer(&tsk->thread.softirq_timer,

				   READ_ONCE(get_lowcore()->softirq_timer));

	get_lowcore()->steal_timer +=

				   READ_ONCE(lc->softirq_timer));

	lc->steal_timer +=

		clock - user - guest - system - hardirq - softirq;



	/* Push account value */
@@ -176,17 +178,19 @@ static int do_account_vtime(struct task_struct *tsk) 


void vtime_task_switch(struct task_struct *prev)

{

	struct lowcore *lc = get_lowcore();



	do_account_vtime(prev);

	prev->thread.user_timer = get_lowcore()->user_timer;

	prev->thread.guest_timer = get_lowcore()->guest_timer;

	prev->thread.system_timer = get_lowcore()->system_timer;

	prev->thread.hardirq_timer = get_lowcore()->hardirq_timer;

	prev->thread.softirq_timer = get_lowcore()->softirq_timer;

	get_lowcore()->user_timer = current->thread.user_timer;

	get_lowcore()->guest_timer = current->thread.guest_timer;

	get_lowcore()->system_timer = current->thread.system_timer;

	get_lowcore()->hardirq_timer = current->thread.hardirq_timer;

	get_lowcore()->softirq_timer = current->thread.softirq_timer;

	prev->thread.user_timer = lc->user_timer;

	prev->thread.guest_timer = lc->guest_timer;

	prev->thread.system_timer = lc->system_timer;

	prev->thread.hardirq_timer = lc->hardirq_timer;

	prev->thread.softirq_timer = lc->softirq_timer;

	lc->user_timer = current->thread.user_timer;

	lc->guest_timer = current->thread.guest_timer;

	lc->system_timer = current->thread.system_timer;

	lc->hardirq_timer = current->thread.hardirq_timer;

	lc->softirq_timer = current->thread.softirq_timer;

}



/*
@@ -196,28 +200,29 @@ void vtime_task_switch(struct task_struct *prev) 
 */

void vtime_flush(struct task_struct *tsk)

{

	struct lowcore *lc = get_lowcore();

	u64 steal, avg_steal;



	if (do_account_vtime(tsk))

		virt_timer_expire();



	steal = get_lowcore()->steal_timer;

	avg_steal = get_lowcore()->avg_steal_timer;

	steal = lc->steal_timer;

	avg_steal = lc->avg_steal_timer;

	if ((s64) steal > 0) {

		get_lowcore()->steal_timer = 0;

		lc->steal_timer = 0;

		account_steal_time(cputime_to_nsecs(steal));

		avg_steal += steal;

	}

	get_lowcore()->avg_steal_timer = avg_steal / 2;

	lc->avg_steal_timer = avg_steal / 2;

}



static u64 vtime_delta(void)

{

	u64 timer = get_lowcore()->last_update_timer;



	get_lowcore()->last_update_timer = get_cpu_timer();

	struct lowcore *lc = get_lowcore();

	u64 timer = lc->last_update_timer;



	return timer - get_lowcore()->last_update_timer;

	lc->last_update_timer = get_cpu_timer();

	return timer - lc->last_update_timer;

}



/*
@@ -226,12 +231,13 @@ static u64 vtime_delta(void) 
 */

void vtime_account_kernel(struct task_struct *tsk)

{

	struct lowcore *lc = get_lowcore();

	u64 delta = vtime_delta();



	if (tsk->flags & PF_VCPU)

		get_lowcore()->guest_timer += delta;

		lc->guest_timer += delta;

	else

		get_lowcore()->system_timer += delta;

		lc->system_timer += delta;



	virt_timer_forward(delta);

}