Author: kib Date: Mon Sep 9 11:29:58 2019 New Revision: 352059 URL: https://svnweb.freebsd.org/changeset/base/352059
Log: Make timehands count selectable at boottime. Tested by: O'Connor, Daniel <[email protected]> Sponsored by: The FreeBSD Foundation MFC after: 1 week Differential revision: https://reviews.freebsd.org/D21563 Modified: head/sys/kern/kern_tc.c Modified: head/sys/kern/kern_tc.c ============================================================================== --- head/sys/kern/kern_tc.c Mon Sep 9 11:22:38 2019 (r352058) +++ head/sys/kern/kern_tc.c Mon Sep 9 11:29:58 2019 (r352059) @@ -83,19 +83,16 @@ struct timehands { struct timehands *th_next; }; -static struct timehands th0; -static struct timehands th1 = { - .th_next = &th0 -}; -static struct timehands th0 = { +static struct timehands ths[16] = { + [0] = { .th_counter = &dummy_timecounter, .th_scale = (uint64_t)-1 / 1000000, .th_offset = { .sec = 1 }, .th_generation = 1, - .th_next = &th1 + }, }; -static struct timehands *volatile timehands = &th0; +static struct timehands *volatile timehands = &ths[0]; struct timecounter *timecounter = &dummy_timecounter; static struct timecounter *timecounters = &dummy_timecounter; @@ -115,6 +112,10 @@ static int timestepwarnings; SYSCTL_INT(_kern_timecounter, OID_AUTO, stepwarnings, CTLFLAG_RW, ×tepwarnings, 0, "Log time steps"); +static int timehands_count = 2; +SYSCTL_INT(_kern_timecounter, OID_AUTO, timehands_count, CTLFLAG_RDTUN, + &timehands_count, 0, "Count of timehands in rotation"); + struct bintime bt_timethreshold; struct bintime bt_tickthreshold; sbintime_t sbt_timethreshold; @@ -1960,8 +1961,9 @@ done: static void inittimecounter(void *dummy) { + struct timehands *thp; u_int p; - int tick_rate; + int i, tick_rate; /* * Set the initial timeout to @@ -1987,6 +1989,16 @@ inittimecounter(void *dummy) #ifdef FFCLOCK ffclock_init(); #endif + + /* Set up the requested number of timehands. */ + if (timehands_count < 1) + timehands_count = 1; + if (timehands_count > nitems(ths)) + timehands_count = nitems(ths); + for (i = 1, thp = &ths[0]; i < timehands_count; thp = &ths[i++]) + thp->th_next = &ths[i]; + thp->th_next = &ths[0]; + /* warm up new timecounter (again) and get rolling. */ (void)timecounter->tc_get_timecount(timecounter); (void)timecounter->tc_get_timecount(timecounter); _______________________________________________ [email protected] mailing list https://lists.freebsd.org/mailman/listinfo/svn-src-head To unsubscribe, send any mail to "[email protected]"
