diff options
Diffstat (limited to 'sys/x86/isa')
-rw-r--r-- | sys/x86/isa/clock.c | 59 |
1 files changed, 29 insertions, 30 deletions
diff --git a/sys/x86/isa/clock.c b/sys/x86/isa/clock.c index b92fcd7..d82dad7 100644 --- a/sys/x86/isa/clock.c +++ b/sys/x86/isa/clock.c @@ -246,40 +246,50 @@ getit(void) } #ifndef DELAYDEBUG -static __inline void -delay_tsc(int n, uint64_t freq) +static u_int +get_tsc(__unused struct timecounter *tc) { - uint64_t start, end, now; - sched_pin(); - start = rdtsc(); - end = start + (freq * n) / 1000000; - do { - cpu_spinwait(); - now = rdtsc(); - } while (now < end || (now > start && end < start)); - sched_unpin(); + return (rdtsc()); } -static __inline void -delay_timecounter(struct timecounter *tc, int n) +static __inline int +delay_tc(int n) { - uint64_t end, now; + struct timecounter *tc; + timecounter_get_t *func; + uint64_t end, freq, now; u_int last, mask, u; - mask = tc->tc_counter_mask; - last = tc->tc_get_timecount(tc) & mask; - end = tc->tc_frequency * n / 1000000; + tc = timecounter; + freq = atomic_load_acq_64(&tsc_freq); + if (freq != 0) { + func = get_tsc; + mask = ~0u; + } else { + if (tc->tc_quality <= 0) + return (0); + func = tc->tc_get_timecount; + mask = tc->tc_counter_mask; + freq = tc->tc_frequency; + } now = 0; + end = freq * n / 1000000; + if (func == get_tsc) + sched_pin(); + last = func(tc) & mask; do { cpu_spinwait(); - u = tc->tc_get_timecount(tc) & mask; + u = func(tc) & mask; if (u < last) now += mask - last + u + 1; else now += u - last; last = u; } while (now < end); + if (func == get_tsc) + sched_unpin(); + return (1); } #endif @@ -306,19 +316,8 @@ DELAY(int n) if (state == 1) printf("DELAY(%d)...", n); #else - struct timecounter *tc; - uint64_t freq; - - freq = atomic_load_acq_64(&tsc_freq); - if (freq != 0) { - delay_tsc(n, freq); + if (delay_tc(n)) return; - } - tc = timecounter; - if (tc->tc_quality > 0) { - delay_timecounter(tc, n); - return; - } #endif /* * Read the counter first, so that the rest of the setup overhead is |