f2fs: support passing down write hints given by users to block layer
Add the 'whint_mode' mount option that controls which write
hints are passed down to block layer. There are "off" and
"user-based" mode. The default mode is "off".
1) whint_mode=off. F2FS only passes down WRITE_LIFE_NOT_SET.
2) whint_mode=user-based. F2FS tries to pass down hints given
by users.
User F2FS Block
---- ---- -----
META WRITE_LIFE_NOT_SET
HOT_NODE "
WARM_NODE "
COLD_NODE "
ioctl(COLD) COLD_DATA WRITE_LIFE_EXTREME
extension list " "
-- buffered io
WRITE_LIFE_EXTREME COLD_DATA WRITE_LIFE_EXTREME
WRITE_LIFE_SHORT HOT_DATA WRITE_LIFE_SHORT
WRITE_LIFE_NOT_SET WARM_DATA WRITE_LIFE_NOT_SET
WRITE_LIFE_NONE " "
WRITE_LIFE_MEDIUM " "
WRITE_LIFE_LONG " "
-- direct io
WRITE_LIFE_EXTREME COLD_DATA WRITE_LIFE_EXTREME
WRITE_LIFE_SHORT HOT_DATA WRITE_LIFE_SHORT
WRITE_LIFE_NOT_SET WARM_DATA WRITE_LIFE_NOT_SET
WRITE_LIFE_NONE " WRITE_LIFE_NONE
WRITE_LIFE_MEDIUM " WRITE_LIFE_MEDIUM
WRITE_LIFE_LONG " WRITE_LIFE_LONG
Many thanks to Chao Yu and Jaegeuk Kim for comments to
implement this patch.
Signed-off-by: Hyunchul Lee <cheol.lee@lge.com>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
[Jaegeuk Kim: avoid build warning]
[Chao Yu: fix to restore whint_mode in ->remount_fs]
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
diff --git a/fs/f2fs/segment.c b/fs/f2fs/segment.c
index 915984a..fbb5539 100644
--- a/fs/f2fs/segment.c
+++ b/fs/f2fs/segment.c
@@ -2456,6 +2456,62 @@
}
}
+/* This returns write hints for each segment type. This hints will be
+ * passed down to block layer. There are mapping tables which depend on
+ * the mount option 'whint_mode'.
+ *
+ * 1) whint_mode=off. F2FS only passes down WRITE_LIFE_NOT_SET.
+ *
+ * 2) whint_mode=user-based. F2FS tries to pass down hints given by users.
+ *
+ * User F2FS Block
+ * ---- ---- -----
+ * META WRITE_LIFE_NOT_SET
+ * HOT_NODE "
+ * WARM_NODE "
+ * COLD_NODE "
+ * ioctl(COLD) COLD_DATA WRITE_LIFE_EXTREME
+ * extension list " "
+ *
+ * -- buffered io
+ * WRITE_LIFE_EXTREME COLD_DATA WRITE_LIFE_EXTREME
+ * WRITE_LIFE_SHORT HOT_DATA WRITE_LIFE_SHORT
+ * WRITE_LIFE_NOT_SET WARM_DATA WRITE_LIFE_NOT_SET
+ * WRITE_LIFE_NONE " "
+ * WRITE_LIFE_MEDIUM " "
+ * WRITE_LIFE_LONG " "
+ *
+ * -- direct io
+ * WRITE_LIFE_EXTREME COLD_DATA WRITE_LIFE_EXTREME
+ * WRITE_LIFE_SHORT HOT_DATA WRITE_LIFE_SHORT
+ * WRITE_LIFE_NOT_SET WARM_DATA WRITE_LIFE_NOT_SET
+ * WRITE_LIFE_NONE " WRITE_LIFE_NONE
+ * WRITE_LIFE_MEDIUM " WRITE_LIFE_MEDIUM
+ * WRITE_LIFE_LONG " WRITE_LIFE_LONG
+ *
+ */
+
+enum rw_hint io_type_to_rw_hint(struct f2fs_sb_info *sbi,
+ enum page_type type, enum temp_type temp)
+{
+ if (sbi->whint_mode == WHINT_MODE_USER) {
+ if (type == DATA) {
+ switch (temp) {
+ case COLD:
+ return WRITE_LIFE_EXTREME;
+ case HOT:
+ return WRITE_LIFE_SHORT;
+ default:
+ return WRITE_LIFE_NOT_SET;
+ }
+ } else {
+ return WRITE_LIFE_NOT_SET;
+ }
+ } else {
+ return WRITE_LIFE_NOT_SET;
+ }
+}
+
static int __get_segment_type_2(struct f2fs_io_info *fio)
{
if (fio->type == DATA)
@@ -2644,6 +2700,7 @@
struct f2fs_io_info fio = {
.sbi = sbi,
.type = META,
+ .temp = HOT,
.op = REQ_OP_WRITE,
.op_flags = REQ_SYNC | REQ_META | REQ_PRIO,
.old_blkaddr = page->index,
@@ -2692,6 +2749,8 @@
int err;
fio->new_blkaddr = fio->old_blkaddr;
+ /* i/o temperature is needed for passing down write hints */
+ __get_segment_type(fio);
stat_inc_inplace_blocks(fio->sbi);
err = f2fs_submit_page_bio(fio);