Deactivation of the expiry cache is done by setting all clock caches to 0. That requires to have a check for zero in all places which update the expiry cache: if (cache == 0 || new < cache) cache = new; Use U64_MAX as the deactivated value, which allows to remove the zero checks when updating the cache and reduces it to the obvious check: if (new < cache) cache = new; This also removes the weird workaround in do_prlimit() which was required to convert a RLIMIT_CPU value of 0 (immediate expiry) to 1 because handing in 0 to the posix CPU timer code would have effectively disarmed it.
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| @@ -86,7 +86,9 @@ struct posix_cputimers { · 85 unmodified lines | ||
| 86 | 86 | |
| 87 | 87 | static inline void posix_cputimers_init(struct posix_cputimers *pct) |
| 88 | 88 | { |
| 89 | − memset(pct->bases, 0, sizeof(pct->bases)); | |
| 89 | + pct->bases[0].nextevt = U64_MAX; | |
| 90 | + pct->bases[1].nextevt = U64_MAX; | |
| 91 | + pct->bases[2].nextevt = U64_MAX; | |
| 90 | 92 | INIT_LIST_HEAD(&pct->bases[0].cpu_timers); |
| 91 | 93 | INIT_LIST_HEAD(&pct->bases[1].cpu_timers); |
| 92 | 94 | INIT_LIST_HEAD(&pct->bases[2].cpu_timers); |
| @@ -102,7 +104,8 @@ static inline void posix_cputimers_rt_watchdog(struct posix_cputimers *pct, · 9 unmodified lines | ||
| 102 | 104 | |
| 103 | 105 | /* Init task static initializer */ |
| 104 | 106 | #define INIT_CPU_TIMERBASE(b) { \ |
| 105 | − .cpu_timers = LIST_HEAD_INIT(b.cpu_timers), \ | |
| 107 | + .nextevt = U64_MAX, \ | |
| 108 | + .cpu_timers = LIST_HEAD_INIT(b.cpu_timers), \ | |
| 106 | 109 | } |
| 107 | 110 | |
| 108 | 111 | #define INIT_CPU_TIMERBASES(b) { \ |