summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorJohannes Sixt <j6t@kdbg.org>2010-04-08 07:15:39 (GMT)
committerJunio C Hamano <gitster@pobox.com>2010-04-09 06:06:39 (GMT)
commit937491944292fa3303b565b9bd8914c6b644ab13 (patch)
treead926dcdc9a88268dcea2f5207ae2959690c18af
parenta9a746364bd26d333c7229c6f7e851b507cd284a (diff)
downloadgit-937491944292fa3303b565b9bd8914c6b644ab13.zip
git-937491944292fa3303b565b9bd8914c6b644ab13.tar.gz
git-937491944292fa3303b565b9bd8914c6b644ab13.tar.bz2
Thread-safe xmalloc and xrealloc needs a recursive mutex
The mutex used to protect object access (read_mutex) may need to be acquired recursively. Introduce init_recursive_mutex() helper function in thread-utils.c that constructs a mutex with the PHREAD_MUTEX_RECURSIVE attribute. pthread_mutex_init() emulation on Win32 is already recursive as it is implemented on top of the CRITICAL_SECTION type, which is recursive. http://msdn.microsoft.com/en-us/library/ms682530%28VS.85%29.aspx Add do-nothing compatibility wrappers for pthread_mutexattr* functions. Initial-version-by: Fredrik Kuivinen <frekui@gmail.com> Signed-off-by: Johannes Sixt <j6t@kdbg.org> Signed-off-by: Junio C Hamano <gitster@pobox.com>
-rw-r--r--builtin-grep.c2
-rw-r--r--builtin-pack-objects.c4
-rw-r--r--compat/win32/pthread.h8
-rw-r--r--thread-utils.c16
-rw-r--r--thread-utils.h1
5 files changed, 27 insertions, 4 deletions
diff --git a/builtin-grep.c b/builtin-grep.c
index 371db0a..52137f4 100644
--- a/builtin-grep.c
+++ b/builtin-grep.c
@@ -16,8 +16,8 @@
#include "quote.h"
#ifndef NO_PTHREADS
-#include "thread-utils.h"
#include <pthread.h>
+#include "thread-utils.h"
#endif
static char const * const grep_usage[] = {
diff --git a/builtin-pack-objects.c b/builtin-pack-objects.c
index 0ecc198..26fc7cd 100644
--- a/builtin-pack-objects.c
+++ b/builtin-pack-objects.c
@@ -18,8 +18,8 @@
#include "refs.h"
#ifndef NO_PTHREADS
-#include "thread-utils.h"
#include <pthread.h>
+#include "thread-utils.h"
#endif
static const char pack_usage[] =
@@ -1586,7 +1586,7 @@ static pthread_cond_t progress_cond;
*/
static void init_threaded_search(void)
{
- pthread_mutex_init(&read_mutex, NULL);
+ init_recursive_mutex(&read_mutex);
pthread_mutex_init(&cache_mutex, NULL);
pthread_mutex_init(&progress_mutex, NULL);
pthread_cond_init(&progress_cond, NULL);
diff --git a/compat/win32/pthread.h b/compat/win32/pthread.h
index c72f100..a45f8d6 100644
--- a/compat/win32/pthread.h
+++ b/compat/win32/pthread.h
@@ -18,11 +18,17 @@
*/
#define pthread_mutex_t CRITICAL_SECTION
-#define pthread_mutex_init(a,b) InitializeCriticalSection((a))
+#define pthread_mutex_init(a,b) (InitializeCriticalSection((a)), 0)
#define pthread_mutex_destroy(a) DeleteCriticalSection((a))
#define pthread_mutex_lock EnterCriticalSection
#define pthread_mutex_unlock LeaveCriticalSection
+typedef int pthread_mutexattr_t;
+#define pthread_mutexattr_init(a) (*(a) = 0)
+#define pthread_mutexattr_destroy(a) do {} while (0)
+#define pthread_mutexattr_settype(a, t) 0
+#define PTHREAD_MUTEX_RECURSIVE 0
+
/*
* Implement simple condition variable for Windows threads, based on ACE
* implementation.
diff --git a/thread-utils.c b/thread-utils.c
index 4f9c829..589f838 100644
--- a/thread-utils.c
+++ b/thread-utils.c
@@ -1,4 +1,5 @@
#include "cache.h"
+#include <pthread.h>
#if defined(hpux) || defined(__hpux) || defined(_hpux)
# include <sys/pstat.h>
@@ -43,3 +44,18 @@ int online_cpus(void)
return 1;
}
+
+int init_recursive_mutex(pthread_mutex_t *m)
+{
+ pthread_mutexattr_t a;
+ int ret;
+
+ ret = pthread_mutexattr_init(&a);
+ if (!ret) {
+ ret = pthread_mutexattr_settype(&a, PTHREAD_MUTEX_RECURSIVE);
+ if (!ret)
+ ret = pthread_mutex_init(m, &a);
+ pthread_mutexattr_destroy(&a);
+ }
+ return ret;
+}
diff --git a/thread-utils.h b/thread-utils.h
index cce4b77..1727a03 100644
--- a/thread-utils.h
+++ b/thread-utils.h
@@ -2,5 +2,6 @@
#define THREAD_COMPAT_H
extern int online_cpus(void);
+extern int init_recursive_mutex(pthread_mutex_t*);
#endif /* THREAD_COMPAT_H */