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| author | kib <kib@FreeBSD.org> | 2015-05-19 14:21:00 +0000 |
|---|---|---|
| committer | kib <kib@FreeBSD.org> | 2015-05-19 14:21:00 +0000 |
| commit | 3ca3bb1c2cbcd54ceae0e6323acca390c2737b0f (patch) | |
| tree | 6aa5b9377300ca1a89860f1d5cf3a2abaf5a6a59 /sys/x86 | |
| parent | d2cafe1802f18314fd0996775fe5accb88210a4f (diff) | |
| download | FreeBSD-src-3ca3bb1c2cbcd54ceae0e6323acca390c2737b0f.zip FreeBSD-src-3ca3bb1c2cbcd54ceae0e6323acca390c2737b0f.tar.gz | |
When sleeping in Sx state using MWAIT instruction, accept fast wakeup
requests from writes to the monitored line.
Submitted by: avg
Diffstat (limited to 'sys/x86')
| -rw-r--r-- | sys/x86/x86/cpu_machdep.c | 23 |
1 files changed, 17 insertions, 6 deletions
diff --git a/sys/x86/x86/cpu_machdep.c b/sys/x86/x86/cpu_machdep.c index 7925713..f07b97e 100644 --- a/sys/x86/x86/cpu_machdep.c +++ b/sys/x86/x86/cpu_machdep.c @@ -101,6 +101,10 @@ __FBSDID("$FreeBSD$"); #include <vm/vm_pager.h> #include <vm/vm_param.h> +#define STATE_RUNNING 0x0 +#define STATE_MWAIT 0x1 +#define STATE_SLEEPING 0x2 + /* * Machine dependent boot() routine * @@ -134,13 +138,24 @@ acpi_cpu_idle_mwait(uint32_t mwait_hint) { int *state; - state = (int *)PCPU_PTR(monitorbuf); /* * XXXKIB. Software coordination mode should be supported, * but all Intel CPUs provide hardware coordination. */ + + state = (int *)PCPU_PTR(monitorbuf); + KASSERT(*state == STATE_SLEEPING, + ("cpu_mwait_cx: wrong monitorbuf state")); + *state = STATE_MWAIT; cpu_monitor(state, 0, 0); - cpu_mwait(MWAIT_INTRBREAK, mwait_hint); + if (*state == STATE_MWAIT) + cpu_mwait(MWAIT_INTRBREAK, mwait_hint); + + /* + * We should exit on any event that interrupts mwait, because + * that event might be a wanted interrupt. + */ + *state = STATE_RUNNING; } /* Get current clock frequency for the given cpu id. */ @@ -231,10 +246,6 @@ static int idle_mwait = 1; /* Use MONITOR/MWAIT for short idle. */ SYSCTL_INT(_machdep, OID_AUTO, idle_mwait, CTLFLAG_RWTUN, &idle_mwait, 0, "Use MONITOR/MWAIT for short idle"); -#define STATE_RUNNING 0x0 -#define STATE_MWAIT 0x1 -#define STATE_SLEEPING 0x2 - #ifndef PC98 static void cpu_idle_acpi(sbintime_t sbt) |
