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authorLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-23 18:09:32 (GMT)
committerLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-23 18:09:32 (GMT)
commit144bde78e9ff22d53682ef46b3d9845b83e70f54 (patch)
tree329aca984ad6d06eb6d2dffae3933f00ccb8df5a /sha1_file.c
parenta6ef3518f9ac8a1c46a36c8d27173b1f73d839c4 (diff)
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Use O_NOATIME when opening the sha1 files.
We really don't care about atime, and it sucks to dirty the inode cache just for it. This is more than a one-liner only because we need to be able to clear the O_NOATIME flag in case some of the objects are owned by others (in which case open will return EPERM), and because not everybody has the O_NOATIME flag.
Diffstat (limited to 'sha1_file.c')
-rw-r--r--sha1_file.c29
1 files changed, 26 insertions, 3 deletions
diff --git a/sha1_file.c b/sha1_file.c
index 6f7228e..66308ed 100644
--- a/sha1_file.c
+++ b/sha1_file.c
@@ -11,6 +11,16 @@
const char *sha1_file_directory = NULL;
+#ifndef O_NOATIME
+#if defined(__linux__) && (defined(__i386__) || defined(__PPC__))
+#define O_NOATIME 01000000
+#else
+#define O_NOATIME 0
+#endif
+#endif
+
+static unsigned int sha1_file_open_flag = O_NOATIME;
+
static unsigned hexval(char c)
{
if (c >= '0' && c <= '9')
@@ -96,13 +106,26 @@ int check_sha1_signature(unsigned char *sha1, void *map, unsigned long size, con
void *map_sha1_file(const unsigned char *sha1, unsigned long *size)
{
char *filename = sha1_file_name(sha1);
- int fd = open(filename, O_RDONLY);
struct stat st;
void *map;
+ int fd;
+ fd = open(filename, O_RDONLY | sha1_file_open_flag);
if (fd < 0) {
- perror(filename);
- return NULL;
+ /* See if it works without O_NOATIME */
+ switch (sha1_file_open_flag) {
+ default:
+ fd = open(filename, O_RDONLY);
+ if (fd >= 0)
+ break;
+ /* Fallthrough */
+ case 0:
+ perror(filename);
+ return NULL;
+ }
+
+ /* If it failed once, it will probably fail again. Stop using O_NOATIME */
+ sha1_file_open_flag = 0;
}
if (fstat(fd, &st) < 0) {
close(fd);