Commit b38a181c authored by Christophe Leroy's avatar Christophe Leroy Committed by Michael Ellerman
Browse files

powerpc/time: isolate scaled cputime accounting in dedicated functions. 



scaled cputime is only meaningfull when the processor has
SPURR and/or PURR, which means only on PPC64.

In preparation of the following patch that will remove
CONFIG_ARCH_HAS_SCALED_CPUTIME on PPC32, this patch moves
all scaled cputing accounting logic into dedicated functions.

This patch doesn't change any functionality. It's only code
reorganisation.

Signed-off-by: default avatarChristophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: default avatarMichael Ellerman <mpe@ellerman.id.au>
parent fb978ca2

arch/powerpc/kernel/time.c

+43 −26
Original line number Diff line number Diff line
@@ -282,26 +282,16 @@ static inline u64 calculate_stolen_time(u64 stop_tb) 
 * Account time for a transition between system, hard irq

 * or soft irq state.

 */

static unsigned long vtime_delta(struct task_struct *tsk,

				 unsigned long *stime_scaled,

				 unsigned long *steal_time)

static unsigned long vtime_delta_scaled(struct cpu_accounting_data *acct,

					unsigned long now, unsigned long stime)

{

	unsigned long now, nowscaled, deltascaled;

	unsigned long stime;

	unsigned long stime_scaled;

	unsigned long nowscaled, deltascaled;

	unsigned long utime, utime_scaled;

	struct cpu_accounting_data *acct = get_accounting(tsk);



	WARN_ON_ONCE(!irqs_disabled());



	now = mftb();

	nowscaled = read_spurr(now);

	stime = now - acct->starttime;

	acct->starttime = now;

	deltascaled = nowscaled - acct->startspurr;

	acct->startspurr = nowscaled;



	*steal_time = calculate_stolen_time(now);



	utime = acct->utime - acct->utime_sspurr;

	acct->utime_sspurr = acct->utime;
@@ -315,18 +305,38 @@ static unsigned long vtime_delta(struct task_struct *tsk, 
	 * the user ticks get saved up in paca->user_time_scaled to be

	 * used by account_process_tick.

	 */

	*stime_scaled = stime;

	stime_scaled = stime;

	utime_scaled = utime;

	if (deltascaled != stime + utime) {

		if (utime) {

			*stime_scaled = deltascaled * stime / (stime + utime);

			utime_scaled = deltascaled - *stime_scaled;

			stime_scaled = deltascaled * stime / (stime + utime);

			utime_scaled = deltascaled - stime_scaled;

		} else {

			*stime_scaled = deltascaled;

			stime_scaled = deltascaled;

		}

	}

	acct->utime_scaled += utime_scaled;



	return stime_scaled;

}



static unsigned long vtime_delta(struct task_struct *tsk,

				 unsigned long *stime_scaled,

				 unsigned long *steal_time)

{

	unsigned long now, stime;

	struct cpu_accounting_data *acct = get_accounting(tsk);



	WARN_ON_ONCE(!irqs_disabled());



	now = mftb();

	stime = now - acct->starttime;

	acct->starttime = now;



	*stime_scaled = vtime_delta_scaled(acct, now, stime);



	*steal_time = calculate_stolen_time(now);



	return stime;

}
@@ -365,6 +375,19 @@ void vtime_account_idle(struct task_struct *tsk) 
	acct->idle_time += stime + steal_time;

}



static void vtime_flush_scaled(struct task_struct *tsk,

			       struct cpu_accounting_data *acct)

{

	if (acct->utime_scaled)

		tsk->utimescaled += cputime_to_nsecs(acct->utime_scaled);

	if (acct->stime_scaled)

		tsk->stimescaled += cputime_to_nsecs(acct->stime_scaled);



	acct->utime_scaled = 0;

	acct->utime_sspurr = 0;

	acct->stime_scaled = 0;

}



/*

 * Account the whole cputime accumulated in the paca

 * Must be called with interrupts disabled.
@@ -379,9 +402,6 @@ void vtime_flush(struct task_struct *tsk) 
	if (acct->utime)

		account_user_time(tsk, cputime_to_nsecs(acct->utime));



	if (acct->utime_scaled)

		tsk->utimescaled += cputime_to_nsecs(acct->utime_scaled);



	if (acct->gtime)

		account_guest_time(tsk, cputime_to_nsecs(acct->gtime));
@@ -394,8 +414,6 @@ void vtime_flush(struct task_struct *tsk) 
	if (acct->stime)

		account_system_index_time(tsk, cputime_to_nsecs(acct->stime),

					  CPUTIME_SYSTEM);

	if (acct->stime_scaled)

		tsk->stimescaled += cputime_to_nsecs(acct->stime_scaled);



	if (acct->hardirq_time)

		account_system_index_time(tsk, cputime_to_nsecs(acct->hardirq_time),
@@ -404,14 +422,13 @@ void vtime_flush(struct task_struct *tsk) 
		account_system_index_time(tsk, cputime_to_nsecs(acct->softirq_time),

					  CPUTIME_SOFTIRQ);



	vtime_flush_scaled(tsk, acct);



	acct->utime = 0;

	acct->utime_scaled = 0;

	acct->utime_sspurr = 0;

	acct->gtime = 0;

	acct->steal_time = 0;

	acct->idle_time = 0;

	acct->stime = 0;

	acct->stime_scaled = 0;

	acct->hardirq_time = 0;

	acct->softirq_time = 0;

}

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