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authorAkinobu Mita <akinobu.mita@gmail.com>2006-12-08 02:39:46 -0800
committerLinus Torvalds <torvalds@woody.osdl.org>2006-12-08 08:29:02 -0800
commitc17bb4951752d3e0f49cd1ea9d2e868422f9e0d6 (patch)
treedcd23ef706ba09edae462528dc11a507b1d17af6 /block/genhd.c
parent[PATCH] fault-injection capability for alloc_pages() (diff)
downloadlinux-dev-c17bb4951752d3e0f49cd1ea9d2e868422f9e0d6.tar.xz
linux-dev-c17bb4951752d3e0f49cd1ea9d2e868422f9e0d6.zip
[PATCH] fault-injection capability for disk IO
This patch provides fault-injection capability for disk IO. Boot option: fail_make_request=<probability>,<interval>,<space>,<times> <interval> -- specifies the interval of failures. <probability> -- specifies how often it should fail in percent. <space> -- specifies the size of free space where disk IO can be issued safely in bytes. <times> -- specifies how many times failures may happen at most. Debugfs: /debug/fail_make_request/interval /debug/fail_make_request/probability /debug/fail_make_request/specifies /debug/fail_make_request/times Example: fail_make_request=10,100,0,-1 echo 1 > /sys/blocks/hda/hda1/make-it-fail generic_make_request() on /dev/hda1 fails once per 10 times. Cc: Jens Axboe <axboe@suse.de> Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Diffstat (limited to 'block/genhd.c')
-rw-r--r--block/genhd.c31
1 files changed, 31 insertions, 0 deletions
diff --git a/block/genhd.c b/block/genhd.c
index 653919d50cd4..457fdac4c17d 100644
--- a/block/genhd.c
+++ b/block/genhd.c
@@ -417,6 +417,34 @@ static struct disk_attribute disk_attr_stat = {
.show = disk_stats_read
};
+#ifdef CONFIG_FAIL_MAKE_REQUEST
+
+static ssize_t disk_fail_store(struct gendisk * disk,
+ const char *buf, size_t count)
+{
+ int i;
+
+ if (count > 0 && sscanf(buf, "%d", &i) > 0) {
+ if (i == 0)
+ disk->flags &= ~GENHD_FL_FAIL;
+ else
+ disk->flags |= GENHD_FL_FAIL;
+ }
+
+ return count;
+}
+static ssize_t disk_fail_read(struct gendisk * disk, char *page)
+{
+ return sprintf(page, "%d\n", disk->flags & GENHD_FL_FAIL ? 1 : 0);
+}
+static struct disk_attribute disk_attr_fail = {
+ .attr = {.name = "make-it-fail", .mode = S_IRUGO | S_IWUSR },
+ .store = disk_fail_store,
+ .show = disk_fail_read
+};
+
+#endif
+
static struct attribute * default_attrs[] = {
&disk_attr_uevent.attr,
&disk_attr_dev.attr,
@@ -424,6 +452,9 @@ static struct attribute * default_attrs[] = {
&disk_attr_removable.attr,
&disk_attr_size.attr,
&disk_attr_stat.attr,
+#ifdef CONFIG_FAIL_MAKE_REQUEST
+ &disk_attr_fail.attr,
+#endif
NULL,
};