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| author | Rich Felker <dalias@aerifal.cx> | 2011-03-24 23:16:52 -0400 |
|---|---|---|
| committer | Rich Felker <dalias@aerifal.cx> | 2011-03-24 23:16:52 -0400 |
| commit | a37452430f93700aeb122d693959ad79d8e43ada (patch) | |
| tree | 6ed8879bddb17c2b0db8c8bbd4778e11912f0767 /src/stdio/__lockfile.c | |
| parent | d8dc2faf1033e134e3a8f39bdf15c065f4d234be (diff) | |
| download | musl-a37452430f93700aeb122d693959ad79d8e43ada.tar.gz musl-a37452430f93700aeb122d693959ad79d8e43ada.tar.xz musl-a37452430f93700aeb122d693959ad79d8e43ada.zip | |
simplify and optimize FILE lock handling
Diffstat (limited to 'src/stdio/__lockfile.c')
| -rw-r--r-- | src/stdio/__lockfile.c | 13 |
1 files changed, 7 insertions, 6 deletions
diff --git a/src/stdio/__lockfile.c b/src/stdio/__lockfile.c index e4320f05..93c94867 100644 --- a/src/stdio/__lockfile.c +++ b/src/stdio/__lockfile.c @@ -3,17 +3,18 @@ void __lockfile(FILE *f) { - int spins; - if (f->owner < 0) return; - if (f->owner && f->owner == __pthread_self()->tid) { + int spins=100000; + int tid; + + if (f->lock < 0) return; + tid = __pthread_self()->tid; + if (f->lock == tid) { while (f->lockcount == INT_MAX); f->lockcount++; return; } - spins = 100000; - while (a_swap(&f->lock, 1)) + while (f->lock || a_cas(&f->lock, 0, tid)) if (spins) spins--, a_spin(); else syscall(SYS_sched_yield); - f->owner = __pthread_self()->tid; f->lockcount = 1; } |