Differential D14827 Diff 40690 sys/kern/kern_clocksource.c

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sys/kern/kern_clocksource.c

Show First 20 Lines • Show All 116 Lines • ▼ Show 20 Lines	struct pcpu_state {
sbintime_t now; /* Last tick time. */		sbintime_t now; /* Last tick time. */
sbintime_t nextevent; /* Next scheduled event on this CPU. */		sbintime_t nextevent; /* Next scheduled event on this CPU. */
sbintime_t nexttick; /* Next timer tick time. */		sbintime_t nexttick; /* Next timer tick time. */
sbintime_t nexthard; /* Next hardclock() event. */		sbintime_t nexthard; /* Next hardclock() event. */
sbintime_t nextstat; /* Next statclock() event. */		sbintime_t nextstat; /* Next statclock() event. */
sbintime_t nextprof; /* Next profclock() event. */		sbintime_t nextprof; /* Next profclock() event. */
sbintime_t nextcall; /* Next callout event. */		sbintime_t nextcall; /* Next callout event. */
sbintime_t nextcallopt; /* Next optional callout event. */		sbintime_t nextcallopt; /* Next optional callout event. */
int ipi; /* This CPU needs IPI. */		bool ipi; /* This CPU needs IPI. */
int idle; /* This CPU is in idle mode. */		bool idle; /* This CPU is in idle mode. */
		bool running; /* handleevents() is running. */
};		};

static DPCPU_DEFINE(struct pcpu_state, timerstate);		static DPCPU_DEFINE(struct pcpu_state, timerstate);
DPCPU_DEFINE(sbintime_t, hardclocktime);		DPCPU_DEFINE(sbintime_t, hardclocktime);

/*		/*
* Timer broadcast IPI handler.		* Timer broadcast IPI handler.
*/		*/
Show All 19 Lines
*/		*/
static int		static int
handleevents(sbintime_t now, int fake)		handleevents(sbintime_t now, int fake)
{		{
sbintime_t t, *hct;		sbintime_t t, *hct;
struct trapframe *frame;		struct trapframe *frame;
struct pcpu_state *state;		struct pcpu_state *state;
int usermode;		int usermode;
int done, runs;		int done, hardruns, profruns, statruns;
		bool calloutready;
		hselaskyUnsubmitted Not Done Inline Actions Where are you setting calloutready to false? hselasky: Where are you setting calloutready to false?

CTR3(KTR_SPARE2, "handle at %d: now %d.%08x",		CTR3(KTR_SPARE2, "handle at %d: now %d.%08x",
curcpu, (int)(now >> 32), (u_int)(now & 0xffffffff));		curcpu, (int)(now >> 32), (u_int)(now & 0xffffffff));
done = 0;		done = 0;
if (fake) {		if (fake) {
frame = NULL;		frame = NULL;
usermode = 0;		usermode = 0;
} else {		} else {
frame = curthread->td_intr_frame;		frame = curthread->td_intr_frame;
usermode = TRAPF_USERMODE(frame);		usermode = TRAPF_USERMODE(frame);
}		}

state = DPCPU_PTR(timerstate);		state = DPCPU_PTR(timerstate);

runs = 0;		/* Acquire lock and determine what work needs to be done. */
		ET_HW_LOCK(state);
		again:
		hardruns = profruns = statruns = 0;
while (now >= state->nexthard) {		while (now >= state->nexthard) {
state->nexthard += tick_sbt;		state->nexthard += tick_sbt;
runs++;		hardruns++;
}		}
if (runs) {		if (hardruns) {
hct = DPCPU_PTR(hardclocktime);		hct = DPCPU_PTR(hardclocktime);
*hct = state->nexthard - tick_sbt;		*hct = state->nexthard - tick_sbt;
if (fake < 2) {
hardclock_cnt(runs, usermode);
done = 1;
}		}
}
runs = 0;
while (now >= state->nextstat) {		while (now >= state->nextstat) {
state->nextstat += statperiod;		state->nextstat += statperiod;
runs++;		statruns++;
}		}
if (runs && fake < 2) {
statclock_cnt(runs, usermode);
done = 1;
}
if (profiling) {		if (profiling) {
runs = 0;
while (now >= state->nextprof) {		while (now >= state->nextprof) {
state->nextprof += profperiod;		state->nextprof += profperiod;
runs++;		profruns++;
}		}
if (runs && !fake) {
profclock_cnt(runs, usermode, TRAPF_PC(frame));
done = 1;
}
} else		} else
state->nextprof = state->nextstat;		state->nextprof = state->nextstat;
if (now >= state->nextcallopt \|\| now >= state->nextcall) {		if (now >= state->nextcallopt \|\| now >= state->nextcall) {
state->nextcall = state->nextcallopt = SBT_MAX;		state->nextcall = state->nextcallopt = SBT_MAX;
callout_process(now);		calloutready = true;
}		}
		state->running = true;

t = getnextcpuevent(0);		/* Drop the lock and do the work. */
		kibUnsubmitted Not Done Inline Actions Is it possible that the function was called without work to do ? If this case has non-trivial number of occurrences, you might consider to calculate done under the lock and not dropping the lock if done == 0. kib: Is it possible that the function was called without work to do ? If this case has non-trivial…
		jtlAuthorUnsubmitted Not Done Inline Actions I'll add a counter and check. jtl: I'll add a counter and check.
		ET_HW_UNLOCK(state);
		if (hardruns && fake < 2) {
		hardclock_cnt(hardruns, usermode);
		done = 1;
		}
		if (statruns && fake < 2) {
		statclock_cnt(statruns, usermode);
		done = 1;
		}
		if (profruns && !fake) {
		profclock_cnt(profruns, usermode, TRAPF_PC(frame));
		done = 1;
		}
		if (calloutready)
		callout_process(now);

		/* Obtain the lock and reschedule the timer. */
ET_HW_LOCK(state);		ET_HW_LOCK(state);
		t = getnextcpuevent(0);
		if (!periodic) {
		now = sbinuptime();
		if (now >= t \|\| now >= state->nextcallopt)
		goto again;
		}
if (!busy) {		if (!busy) {
state->idle = 0;		state->idle = 0;
state->nextevent = t;		state->nextevent = t;
loadtimer(now, (fake == 2) &&		loadtimer(now, (fake == 2) &&
(timer->et_flags & ET_FLAGS_PERCPU));		(timer->et_flags & ET_FLAGS_PERCPU));
}		}
		state->running = false;
ET_HW_UNLOCK(state);		ET_HW_UNLOCK(state);
return (done);		return (done);
}		}

/*		/*
* Schedule binuptime of the next event on current CPU.		* Schedule binuptime of the next event on current CPU.
*/		*/
static sbintime_t		static sbintime_t
▲ Show 20 Lines • Show All 360 Lines • ▼ Show 20 Lines	cpu_initclocks_bsp(void)
int base, div, cpu;		int base, div, cpu;

mtx_init(&et_hw_mtx, "et_hw_mtx", NULL, MTX_SPIN);		mtx_init(&et_hw_mtx, "et_hw_mtx", NULL, MTX_SPIN);
CPU_FOREACH(cpu) {		CPU_FOREACH(cpu) {
state = DPCPU_ID_PTR(cpu, timerstate);		state = DPCPU_ID_PTR(cpu, timerstate);
mtx_init(&state->et_hw_mtx, "et_hw_mtx", NULL, MTX_SPIN);		mtx_init(&state->et_hw_mtx, "et_hw_mtx", NULL, MTX_SPIN);
state->nextcall = SBT_MAX;		state->nextcall = SBT_MAX;
state->nextcallopt = SBT_MAX;		state->nextcallopt = SBT_MAX;
		state->ipi = state->idle = state->running = false;
}		}
periodic = want_periodic;		periodic = want_periodic;
/* Grab requested timer or the best of present. */		/* Grab requested timer or the best of present. */
if (timername[0])		if (timername[0])
timer = et_find(timername, 0, 0);		timer = et_find(timername, 0, 0);
if (timer == NULL && periodic) {		if (timer == NULL && periodic) {
timer = et_find(NULL,		timer = et_find(NULL,
ET_FLAGS_PERIODIC, ET_FLAGS_PERIODIC);		ET_FLAGS_PERIODIC, ET_FLAGS_PERIODIC);
▲ Show 20 Lines • Show All 229 Lines • ▼ Show 20 Lines	cpu_new_callout(int cpu, sbintime_t bt, sbintime_t bt_opt)
* and scheduling.		* and scheduling.
*/		*/
state->nextcallopt = bt_opt;		state->nextcallopt = bt_opt;
if (bt >= state->nextcall)		if (bt >= state->nextcall)
goto done;		goto done;
state->nextcall = bt;		state->nextcall = bt;
/* If there is some other event set earlier -- do nothing. */		/* If there is some other event set earlier -- do nothing. */
if (bt >= state->nextevent)		if (bt >= state->nextevent)
		goto done;
		/*
		* If handleevents() is running, it will pick up the earlier
		* callout and schedule the correct execution at the correct
		* time.
		*/
		if (state->running)
goto done;		goto done;
state->nextevent = bt;		state->nextevent = bt;
/* If timer is periodic -- there is nothing to reprogram. */		/* If timer is periodic -- there is nothing to reprogram. */
if (periodic)		if (periodic)
goto done;		goto done;
/* If timer is global or of the current CPU -- reprogram it. */		/* If timer is global or of the current CPU -- reprogram it. */
if ((timer->et_flags & ET_FLAGS_PERCPU) == 0 \|\| cpu == curcpu) {		if ((timer->et_flags & ET_FLAGS_PERCPU) == 0 \|\| cpu == curcpu) {
loadtimer(sbinuptime(), 0);		loadtimer(sbinuptime(), 0);
▲ Show 20 Lines • Show All 117 Lines • Show Last 20 Lines