optimize file locking: avoid cache-polluting writes to global storage

4d9cc0b3 · Rich Felker · 9dd7d7e3 · 4d9cc0b3 · 4d9cc0b3
隐藏空白更改
内联并排

Showing with 5 addition and 3 deletion

src/stdio/flockfile.c src/stdio/flockfile.c +4 -2

src/stdio/ftrylockfile.c src/stdio/ftrylockfile.c +1 -1

未找到文件。
--- a/src/stdio/flockfile.c
+++ b/src/stdio/flockfile.c
@@ -3,7 +3,9 @@

 void flockfile(FILE *f)
 {
-	pthread_self();
-	libc.lockfile = __lockfile;
+	if (!libc.lockfile) {
+		pthread_self();
+		libc.lockfile = __lockfile;
+	}
 	__lockfile(f);
 }
--- a/src/stdio/ftrylockfile.c
+++ b/src/stdio/ftrylockfile.c
@@ -3,7 +3,7 @@

 int ftrylockfile(FILE *f)
 {
-	libc.lockfile = __lockfile;
+	if (!libc.lockfile) libc.lockfile = __lockfile;
 	if (f->owner && f->owner == pthread_self()->tid) {
 		if (f->lockcount == INT_MAX)
 			return -1;