Introduce pthread_condattr_setclock()

This is one of the few POSIX APIs that was missing. It lets you choose a
monotonic clock for your condition variables. This might improve perf on
some platforms. It might also grant more flexibility with NTP configs. I
know Qt is one project that believes it needs this. To introduce this, I
needed to change some the *NSYNC APIs, to support passing a clock param.
There's also new benchmarks, demonstrating Cosmopolitan's supremacy over
many libc implementations when it comes to mutex performance. Cygwin has
an alarmingly bad pthread_mutex_t implementation. It is so bad that they
would have been significantly better off if they'd used naive spinlocks.
This commit is contained in:
Justine Tunney 2024-09-02 23:37:50 -07:00
parent 79516bf08e
commit 3c61a541bd
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55 changed files with 449 additions and 155 deletions

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@ -266,7 +266,7 @@ void nsync_mu_unlock_slow_(nsync_mu *mu, lock_type *l_type);
struct Dll *nsync_remove_from_mu_queue_(struct Dll *mu_queue, struct Dll *e);
void nsync_maybe_merge_conditions_(struct Dll *p, struct Dll *n);
nsync_time nsync_note_notified_deadline_(nsync_note n);
int nsync_sem_wait_with_cancel_(waiter *w, nsync_time abs_deadline,
int nsync_sem_wait_with_cancel_(waiter *w, int clock, nsync_time abs_deadline,
nsync_note cancel_note);
COSMOPOLITAN_C_END_