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Move time math out of disabled interrupts sections.

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We don't need the result before next sleep time, so no reason to
additionally increase interrupt latency.

While there, remove extra PM ticks to microseconds conversion, making
C2/C3 sleep times look 4 times smaller than really.  The conversion
is already done by AcpiGetTimerDuration().  Now I see reported sleep
times up to 0.5s, just as expected for planned 2 wakeups per second.

MFC after:	1 month
This commit is contained in:
Alexander Motin 2021-03-10 13:39:15 -05:00
parent c328f64d81
commit 2cee045b4d
1 changed files with 16 additions and 14 deletions
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30
sys/dev/acpica/acpi_cpu.c
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@ -114,8 +114,6 @@ struct acpi_cpu_device {
(bus_space_write_ ## width(rman_get_bustag((reg)), \
rman_get_bushandle((reg)), 0, (val)))
#define PM_USEC(x) ((x) >> 2) /* ~4 clocks per usec (3.57955 Mhz) */
#define ACPI_NOTIFY_CX_STATES 0x81 /* _CST changed. */
#define CPU_QUIRK_NO_C3 (1<<0) /* C3-type states are not usable. */
@ -1107,7 +1105,7 @@ acpi_cpu_idle(sbintime_t sbt)
{
struct acpi_cpu_softc *sc;
struct acpi_cx *cx_next;
uint64_t cputicks;
uint64_t start_ticks, end_ticks;
uint32_t start_time, end_time;
ACPI_STATUS status;
int bm_active, cx_next_idx, i, us;
@ -1176,7 +1174,7 @@ acpi_cpu_idle(sbintime_t sbt)
* we are called inside critical section, delaying context switch.
*/
if (cx_next->type == ACPI_STATE_C1) {
cputicks = cpu_ticks();
start_ticks = cpu_ticks();
if (cx_next->p_lvlx != NULL) {
/* C1 I/O then Halt */
CPU_GET_REG(cx_next->p_lvlx, 1);
@ -1185,12 +1183,13 @@ acpi_cpu_idle(sbintime_t sbt)
acpi_cpu_idle_mwait(cx_next->mwait_hint);
else
acpi_cpu_c1();
end_time = ((cpu_ticks() - cputicks) << 20) / cpu_tickrate();
if (curthread->td_critnest == 0)
end_time = min(end_time, 500000 / hz);
end_ticks = cpu_ticks();
/* acpi_cpu_c1() returns with interrupts enabled. */
if (cx_next->do_mwait)
ACPI_ENABLE_IRQS();
end_time = ((end_ticks - start_ticks) << 20) / cpu_tickrate();
if (!cx_next->do_mwait && curthread->td_critnest == 0)
end_time = min(end_time, 500000 / hz);
sc->cpu_prev_sleep = (sc->cpu_prev_sleep * 3 + end_time) / 4;
return;
}
@ -1215,10 +1214,10 @@ acpi_cpu_idle(sbintime_t sbt)
*/
if (cx_next->type == ACPI_STATE_C3) {
AcpiGetTimer(&start_time);
cputicks = 0;
start_ticks = 0;
} else {
start_time = 0;
cputicks = cpu_ticks();
start_ticks = cpu_ticks();
}
if (cx_next->do_mwait) {
acpi_cpu_idle_mwait(cx_next->mwait_hint);
@ -1233,11 +1232,10 @@ acpi_cpu_idle(sbintime_t sbt)
AcpiGetTimer(&end_time);
}
if (cx_next->type == ACPI_STATE_C3) {
if (cx_next->type == ACPI_STATE_C3)
AcpiGetTimer(&end_time);
AcpiGetTimerDuration(start_time, end_time, &end_time);
} else
end_time = ((cpu_ticks() - cputicks) << 20) / cpu_tickrate();
else
end_ticks = cpu_ticks();
/* Enable bus master arbitration and disable bus master wakeup. */
if (cx_next->type == ACPI_STATE_C3 &&
@ -1247,7 +1245,11 @@ acpi_cpu_idle(sbintime_t sbt)
}
ACPI_ENABLE_IRQS();
sc->cpu_prev_sleep = (sc->cpu_prev_sleep * 3 + PM_USEC(end_time)) / 4;
if (cx_next->type == ACPI_STATE_C3)
AcpiGetTimerDuration(start_time, end_time, &end_time);
else
end_time = ((end_ticks - start_ticks) << 20) / cpu_tickrate();
sc->cpu_prev_sleep = (sc->cpu_prev_sleep * 3 + end_time) / 4;
}
#endif