diff --git a/sys/amd64/amd64/local_apic.c b/sys/amd64/amd64/local_apic.c index 47bb78dadf56..7f31e1cc82ae 100644 --- a/sys/amd64/amd64/local_apic.c +++ b/sys/amd64/amd64/local_apic.c @@ -77,10 +77,6 @@ CTASSERT(APIC_TIMER_INT < APIC_LOCAL_INTS); CTASSERT(APIC_LOCAL_INTS == 240); CTASSERT(IPI_STOP < APIC_SPURIOUS_INT); -#define LAPIC_TIMER_HZ_DIVIDER 2 -#define LAPIC_TIMER_STATHZ_DIVIDER 15 -#define LAPIC_TIMER_PROFHZ_DIVIDER 3 - /* Magic IRQ values for the timer and syscalls. */ #define IRQ_TIMER (NUM_IO_INTS + 1) #define IRQ_SYSCALL (NUM_IO_INTS + 2) @@ -389,13 +385,24 @@ lapic_setup_clock(void) lapic_timer_divisor, value); /* - * We will drive the timer at a small multiple of hz and drive - * both of the other timers with similarly small but relatively - * prime divisors. + * We want to run stathz in the neighborhood of 128hz. We would + * like profhz to run as often as possible, so we let it run on + * each clock tick. We try to honor the requested 'hz' value as + * much as possible. + * + * If 'hz' is above 1500, then we just let the lapic timer + * (and profhz) run at hz. If 'hz' is below 1500 but above + * 750, then we let the lapic timer run at 2 * 'hz'. If 'hz' + * is below 750 then we let the lapic timer run at 4 * 'hz'. */ - lapic_timer_hz = hz * LAPIC_TIMER_HZ_DIVIDER; - stathz = lapic_timer_hz / LAPIC_TIMER_STATHZ_DIVIDER; - profhz = lapic_timer_hz / LAPIC_TIMER_PROFHZ_DIVIDER; + if (hz >= 1500) + lapic_timer_hz = hz; + else if (hz >= 750) + lapic_timer_hz = hz * 2; + else + lapic_timer_hz = hz * 4; + stathz = lapic_timer_hz / (lapic_timer_hz / 128); + profhz = lapic_timer_hz; lapic_timer_period = value / lapic_timer_hz; /* diff --git a/sys/i386/i386/local_apic.c b/sys/i386/i386/local_apic.c index ffdcdf62cd34..664b1867bb2e 100644 --- a/sys/i386/i386/local_apic.c +++ b/sys/i386/i386/local_apic.c @@ -77,10 +77,6 @@ CTASSERT(APIC_TIMER_INT < APIC_LOCAL_INTS); CTASSERT(APIC_LOCAL_INTS == 240); CTASSERT(IPI_STOP < APIC_SPURIOUS_INT); -#define LAPIC_TIMER_HZ_DIVIDER 2 -#define LAPIC_TIMER_STATHZ_DIVIDER 15 -#define LAPIC_TIMER_PROFHZ_DIVIDER 3 - /* Magic IRQ values for the timer and syscalls. */ #define IRQ_TIMER (NUM_IO_INTS + 1) #define IRQ_SYSCALL (NUM_IO_INTS + 2) @@ -391,13 +387,24 @@ lapic_setup_clock(void) lapic_timer_divisor, value); /* - * We will drive the timer at a small multiple of hz and drive - * both of the other timers with similarly small but relatively - * prime divisors. + * We want to run stathz in the neighborhood of 128hz. We would + * like profhz to run as often as possible, so we let it run on + * each clock tick. We try to honor the requested 'hz' value as + * much as possible. + * + * If 'hz' is above 1500, then we just let the lapic timer + * (and profhz) run at hz. If 'hz' is below 1500 but above + * 750, then we let the lapic timer run at 2 * 'hz'. If 'hz' + * is below 750 then we let the lapic timer run at 4 * 'hz'. */ - lapic_timer_hz = hz * LAPIC_TIMER_HZ_DIVIDER; - stathz = lapic_timer_hz / LAPIC_TIMER_STATHZ_DIVIDER; - profhz = lapic_timer_hz / LAPIC_TIMER_PROFHZ_DIVIDER; + if (hz >= 1500) + lapic_timer_hz = hz; + else if (hz >= 750) + lapic_timer_hz = hz * 2; + else + lapic_timer_hz = hz * 4; + stathz = lapic_timer_hz / (lapic_timer_hz / 128); + profhz = lapic_timer_hz; lapic_timer_period = value / lapic_timer_hz; /*