From: Joel Rosdahl <joel@rosdahl.net>
Date: Wed, 26 Feb 2020 21:48:31 +0000 (+0100)
Subject: Cap time to sleep to 10 ms when failing to acquire a lock
X-Git-Tag: v3.7.8~5
X-Git-Url: http://git.ipfire.org/gitweb/gitweb.cgi?a=commitdiff_plain;h=41ffc7ec009237da51040c6059b1bcd7903af30d;p=thirdparty%2Fccache.git

Cap time to sleep to 10 ms when failing to acquire a lock
---

diff --git a/src/lockfile.c b/src/lockfile.c
index 9d1a49db2..0bdb87739 100644
--- a/src/lockfile.c
+++ b/src/lockfile.c
@@ -1,4 +1,4 @@
-// Copyright (C) 2010-2018 Joel Rosdahl
+// Copyright (C) 2010-2020 Joel Rosdahl
 //
 // This program is free software; you can redistribute it and/or modify it
 // under the terms of the GNU General Public License as published by the Free
@@ -34,6 +34,7 @@ lockfile_acquire(const char *path, unsigned staleness_limit)
 	const char *hostname = get_hostname();
 	bool acquired = false;
 	unsigned to_sleep = 1000; // Microseconds.
+	unsigned max_to_sleep = 10000; // Microseconds.
 	unsigned slept = 0; // Microseconds.
 
 	while (true) {
@@ -164,7 +165,7 @@ lockfile_acquire(const char *path, unsigned staleness_limit)
 		       lockfile, to_sleep);
 		usleep(to_sleep);
 		slept += to_sleep;
-		to_sleep *= 2;
+		to_sleep = MIN(max_to_sleep, 2 * to_sleep);
 	}
 
 out: