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| author | Mark Johnston <markj@FreeBSD.org> | 2021-10-29 14:29:22 -0400 |
|---|---|---|
| committer | Sebastian Huber <sebastian.huber@embedded-brains.de> | 2021-11-15 08:56:54 +0100 |
| commit | c3a68059d8a9a149c5c82550f37316cc41e390ec (patch) | |
| tree | 1f5b4cd34141c9141edcad4c6a8c94ad7bd37b76 | |
| parent | kern_tc.c: Scaling/large delta recalculation (diff) | |
| download | rtems-c3a68059d8a9a149c5c82550f37316cc41e390ec.tar.bz2 | |
timecounter: Load the currently selected tc once in tc_windup()
Reported by: Sebastian Huber <sebastian.huber@embedded-brains.de>
Reviewed by: kib
MFC after: 1 week
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D32729
| -rw-r--r-- | cpukit/score/src/kern_tc.c | 23 |
1 files changed, 16 insertions, 7 deletions
diff --git a/cpukit/score/src/kern_tc.c b/cpukit/score/src/kern_tc.c index a2e79b0b25..be3b4c2404 100644 --- a/cpukit/score/src/kern_tc.c +++ b/cpukit/score/src/kern_tc.c @@ -127,6 +127,13 @@ atomic_store_rel_int(Atomic_Uint *i, u_int val) _Atomic_Store_uint(i, val, ATOMIC_ORDER_RELEASE); } + +static inline void * +atomic_load_ptr(void *ptr) +{ + + return ((void *)_Atomic_Load_uintptr(ptr, ATOMIC_ORDER_RELAXED)); +} #endif /* __rtems__ */ /* @@ -1576,6 +1583,7 @@ _Timecounter_Windup(struct bintime *new_boottimebin, #endif /* __rtems__ */ { struct bintime bt; + struct timecounter *tc; struct timehands *th, *tho; uint32_t delta, ncount, ogen; int i; @@ -1610,9 +1618,10 @@ _Timecounter_Windup(struct bintime *new_boottimebin, * changing timecounters, a counter value from the new timecounter. * Update the offset fields accordingly. */ + tc = atomic_load_ptr(&timecounter); delta = tc_delta(th); - if (th->th_counter != timecounter) - ncount = timecounter->tc_get_timecount(timecounter); + if (th->th_counter != tc) + ncount = tc->tc_get_timecount(tc); else ncount = 0; #ifdef FFCLOCK @@ -1678,20 +1687,20 @@ _Timecounter_Windup(struct bintime *new_boottimebin, bintime2timespec(&bt, &th->th_nanotime); /* Now is a good time to change timecounters. */ - if (th->th_counter != timecounter) { + if (th->th_counter != tc) { #ifndef __rtems__ #ifndef __arm__ - if ((timecounter->tc_flags & TC_FLAGS_C2STOP) != 0) + if ((tc->tc_flags & TC_FLAGS_C2STOP) != 0) cpu_disable_c2_sleep++; if ((th->th_counter->tc_flags & TC_FLAGS_C2STOP) != 0) cpu_disable_c2_sleep--; #endif #endif /* __rtems__ */ - th->th_counter = timecounter; + th->th_counter = tc; th->th_offset_count = ncount; #ifndef __rtems__ - tc_min_ticktock_freq = max(1, timecounter->tc_frequency / - (((uint64_t)timecounter->tc_counter_mask + 1) / 3)); + tc_min_ticktock_freq = max(1, tc->tc_frequency / + (((uint64_t)tc->tc_counter_mask + 1) / 3)); #endif /* __rtems__ */ recalculate_scaling_factor_and_large_delta(th); #ifdef FFCLOCK |