From 078d1b2c2263690f2f6b7217b567eeeb525910d0 Mon Sep 17 00:00:00 2001
From: Igor Sysoev <igor@sysoev.ru>
Date: Wed, 30 Jun 2004 15:30:41 +0000
Subject: nginx-0.0.7-2004-06-30-19:30:41 import

---
 src/core/ngx_spinlock.c | 29 +++++++++++++++++++++++++++++
 1 file changed, 29 insertions(+)
 create mode 100644 src/core/ngx_spinlock.c

(limited to 'src/core/ngx_spinlock.c')

diff --git a/src/core/ngx_spinlock.c b/src/core/ngx_spinlock.c
new file mode 100644
index 000000000..c3c65d303
--- /dev/null
+++ b/src/core/ngx_spinlock.c
@@ -0,0 +1,29 @@
+
+#include <ngx_config.h>
+#include <ngx_core.h>
+
+
+void ngx_spinlock(ngx_atomic_t *lock, ngx_uint_t spin)
+{
+    ngx_uint_t  tries;
+
+    tries = 0;
+
+    for ( ;; ) {
+
+        if (*lock) {
+            if (ngx_ncpu > 1 && tries++ < spin) {
+                continue;
+            }
+
+            ngx_sched_yield();
+
+            tries = 0;
+
+        } else {
+            if (ngx_atomic_cmp_set(lock, 0, 1)) {
+                return;
+            }
+        }
+    }
+}
-- 
cgit