Merge pull request #884 from carlosmn/global-windows Make the memory-window conrol structures global
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diff --git a/src/global.c b/src/global.c
index 368c6c6..691f0d4 100644
--- a/src/global.c
+++ b/src/global.c
@@ -9,6 +9,9 @@
#include "git2/threads.h"
#include "thread-utils.h"
+
+git_mutex git__mwindow_mutex;
+
/**
* Handle the global state with TLS
*
@@ -47,12 +50,14 @@ void git_threads_init(void)
_tls_index = TlsAlloc();
_tls_init = 1;
+ git_mutex_init(&git__mwindow_mutex);
}
void git_threads_shutdown(void)
{
TlsFree(_tls_index);
_tls_init = 0;
+ git_mutex_free(&git__mwindow_mutex);
}
git_global_st *git__global_state(void)
diff --git a/src/global.h b/src/global.h
index 6e7373f..0ad41ee 100644
--- a/src/global.h
+++ b/src/global.h
@@ -12,12 +12,12 @@
typedef struct {
git_error *last_error;
git_error error_t;
-
- git_mwindow_ctl mem_ctl;
} git_global_st;
git_global_st *git__global_state(void);
+extern git_mutex git__mwindow_mutex;
+
#define GIT_GLOBAL (git__global_state())
#endif
diff --git a/src/mwindow.c b/src/mwindow.c
index 1a5446b..4da5bad 100644
--- a/src/mwindow.c
+++ b/src/mwindow.c
@@ -32,14 +32,20 @@ static struct {
DEFAULT_MAPPED_LIMIT,
};
+/* Whenever you want to read or modify this, grab git__mwindow_mutex */
+static git_mwindow_ctl mem_ctl;
+
/*
* Free all the windows in a sequence, typically because we're done
* with the file
*/
void git_mwindow_free_all(git_mwindow_file *mwf)
{
- git_mwindow_ctl *ctl = &GIT_GLOBAL->mem_ctl;
+ git_mwindow_ctl *ctl = &mem_ctl;
unsigned int i;
+
+ git_mutex_lock(&git__mwindow_mutex);
+
/*
* Remove these windows from the global list
*/
@@ -67,6 +73,8 @@ void git_mwindow_free_all(git_mwindow_file *mwf)
mwf->windows = w->next;
git__free(w);
}
+
+ git_mutex_unlock(&git__mwindow_mutex);
}
/*
@@ -82,7 +90,7 @@ int git_mwindow_contains(git_mwindow *win, git_off_t offset)
/*
* Find the least-recently-used window in a file
*/
-void git_mwindow_scan_lru(
+static void git_mwindow_scan_lru(
git_mwindow_file *mwf,
git_mwindow **lru_w,
git_mwindow **lru_l)
@@ -107,11 +115,12 @@ void git_mwindow_scan_lru(
/*
* Close the least recently used window. You should check to see if
- * the file descriptors need closing from time to time.
+ * the file descriptors need closing from time to time. Called under
+ * lock from new_window.
*/
static int git_mwindow_close_lru(git_mwindow_file *mwf)
{
- git_mwindow_ctl *ctl = &GIT_GLOBAL->mem_ctl;
+ git_mwindow_ctl *ctl = &mem_ctl;
unsigned int i;
git_mwindow *lru_w = NULL, *lru_l = NULL, **list = &mwf->windows;
@@ -146,13 +155,14 @@ static int git_mwindow_close_lru(git_mwindow_file *mwf)
return 0;
}
+/* This gets called under lock from git_mwindow_open */
static git_mwindow *new_window(
git_mwindow_file *mwf,
git_file fd,
git_off_t size,
git_off_t offset)
{
- git_mwindow_ctl *ctl = &GIT_GLOBAL->mem_ctl;
+ git_mwindow_ctl *ctl = &mem_ctl;
size_t walign = _mw_options.window_size / 2;
git_off_t len;
git_mwindow *w;
@@ -208,9 +218,10 @@ unsigned char *git_mwindow_open(
size_t extra,
unsigned int *left)
{
- git_mwindow_ctl *ctl = &GIT_GLOBAL->mem_ctl;
+ git_mwindow_ctl *ctl = &mem_ctl;
git_mwindow *w = *cursor;
+ git_mutex_lock(&git__mwindow_mutex);
if (!w || !(git_mwindow_contains(w, offset) && git_mwindow_contains(w, offset + extra))) {
if (w) {
w->inuse_cnt--;
@@ -228,8 +239,10 @@ unsigned char *git_mwindow_open(
*/
if (!w) {
w = new_window(mwf, mwf->fd, mwf->size, offset);
- if (w == NULL)
+ if (w == NULL) {
+ git_mutex_unlock(&git__mwindow_mutex);
return NULL;
+ }
w->next = mwf->windows;
mwf->windows = w;
}
@@ -247,32 +260,43 @@ unsigned char *git_mwindow_open(
if (left)
*left = (unsigned int)(w->window_map.len - offset);
+ git_mutex_unlock(&git__mwindow_mutex);
return (unsigned char *) w->window_map.data + offset;
}
int git_mwindow_file_register(git_mwindow_file *mwf)
{
- git_mwindow_ctl *ctl = &GIT_GLOBAL->mem_ctl;
+ git_mwindow_ctl *ctl = &mem_ctl;
+ int ret;
+ git_mutex_lock(&git__mwindow_mutex);
if (ctl->windowfiles.length == 0 &&
- git_vector_init(&ctl->windowfiles, 8, NULL) < 0)
+ git_vector_init(&ctl->windowfiles, 8, NULL) < 0) {
+ git_mutex_unlock(&git__mwindow_mutex);
return -1;
+ }
+
+ ret = git_vector_insert(&ctl->windowfiles, mwf);
+ git_mutex_unlock(&git__mwindow_mutex);
- return git_vector_insert(&ctl->windowfiles, mwf);
+ return ret;
}
int git_mwindow_file_deregister(git_mwindow_file *mwf)
{
- git_mwindow_ctl *ctl = &GIT_GLOBAL->mem_ctl;
+ git_mwindow_ctl *ctl = &mem_ctl;
git_mwindow_file *cur;
unsigned int i;
+ git_mutex_lock(&git__mwindow_mutex);
git_vector_foreach(&ctl->windowfiles, i, cur) {
if (cur == mwf) {
git_vector_remove(&ctl->windowfiles, i);
+ git_mutex_unlock(&git__mwindow_mutex);
return 0;
}
}
+ git_mutex_unlock(&git__mwindow_mutex);
giterr_set(GITERR_ODB, "Failed to find the memory window file to deregister");
return -1;
@@ -282,7 +306,9 @@ void git_mwindow_close(git_mwindow **window)
{
git_mwindow *w = *window;
if (w) {
+ git_mutex_lock(&git__mwindow_mutex);
w->inuse_cnt--;
+ git_mutex_unlock(&git__mwindow_mutex);
*window = NULL;
}
}
diff --git a/src/mwindow.h b/src/mwindow.h
index d4fd195..c5aeaf7 100644
--- a/src/mwindow.h
+++ b/src/mwindow.h
@@ -38,7 +38,6 @@ typedef struct git_mwindow_ctl {
int git_mwindow_contains(git_mwindow *win, git_off_t offset);
void git_mwindow_free_all(git_mwindow_file *mwf);
unsigned char *git_mwindow_open(git_mwindow_file *mwf, git_mwindow **cursor, git_off_t offset, size_t extra, unsigned int *left);
-void git_mwindow_scan_lru(git_mwindow_file *mwf, git_mwindow **lru_w, git_mwindow **lru_l);
int git_mwindow_file_register(git_mwindow_file *mwf);
int git_mwindow_file_deregister(git_mwindow_file *mwf);
void git_mwindow_close(git_mwindow **w_cursor);