This patch enables the async write capability in md. It requires the md
bitmap patches and the 117-WriteMostly-update patch.
Signed-Off-By: Paul Clements <paul.clements@xxxxxxxxxxxx>
drivers/md/bitmap.c | 26 ++++++++++++++++++++++----
drivers/md/md.c | 13 +++++++++++++
include/linux/raid/bitmap.h | 17 +++++++++++------
include/linux/raid/md_k.h | 3 +++
4 files changed, 49 insertions(+), 10 deletions(-)
diff -purN --exclude core --exclude-from /export/public/clemep/tmp/dontdiff linux-2.6.11-rc3-mm2-patch-all-write-mostly-max-dev-bug-bitmap-bug-fix/drivers/md/bitmap.c linux-2.6.11-rc3-mm2-patch-all-write-mostly-async-write-bitmap-bug-fix/drivers/md/bitmap.c
--- linux-2.6.11-rc3-mm2-patch-all-write-mostly-max-dev-bug-bitmap-bug-fix/drivers/md/bitmap.c Thu Mar 10 10:05:35 2005
+++ linux-2.6.11-rc3-mm2-patch-all-write-mostly-async-write-bitmap-bug-fix/drivers/md/bitmap.c Thu Mar 10 10:13:15 2005
@@ -379,6 +379,7 @@ void bitmap_print_sb(struct bitmap *bitm
printk(KERN_DEBUG " daemon sleep: %ds\n", le32_to_cpu(sb->daemon_sleep));
printk(KERN_DEBUG " sync size: %llu KB\n", (unsigned long long)
le64_to_cpu(sb->sync_size) / 2);
+ printk(KERN_DEBUG " async writes: %d\n", le32_to_cpu(sb->async_writes));
kunmap(bitmap->sb_page);
}
@@ -387,7 +388,7 @@ static int bitmap_read_sb(struct bitmap
{
char *reason = NULL;
bitmap_super_t *sb;
- unsigned long chunksize, daemon_sleep;
+ unsigned long chunksize, daemon_sleep, async_writes;
unsigned long bytes_read;
unsigned long long events;
int err = -EINVAL;
@@ -411,6 +412,7 @@ static int bitmap_read_sb(struct bitmap
chunksize = le32_to_cpu(sb->chunksize);
daemon_sleep = le32_to_cpu(sb->daemon_sleep);
+ async_writes = le32_to_cpu(sb->async_writes);
/* verify that the bitmap-specific fields are valid */
if (sb->magic != cpu_to_le32(BITMAP_MAGIC))
@@ -422,7 +424,9 @@ static int bitmap_read_sb(struct bitmap
else if ((1 << ffz(~chunksize)) != chunksize)
reason = "bitmap chunksize not a power of 2";
else if (daemon_sleep < 1 || daemon_sleep > 15)
- reason = "daemon sleep period out of range";
+ reason = "daemon sleep period out of range (1-15s)";
+ else if (async_writes > COUNTER_MAX)
+ reason = "async write limit of range (0 - 16383)";
if (reason) {
printk(KERN_INFO "%s: invalid bitmap file superblock: %s\n",
bmname(bitmap), reason);
@@ -455,6 +459,7 @@ success:
/* assign fields using values from superblock */
bitmap->chunksize = chunksize;
bitmap->daemon_sleep = daemon_sleep;
+ bitmap->async_max_writes = async_writes;
bitmap->flags |= sb->state;
bitmap->events_cleared = le64_to_cpu(sb->events_cleared);
err = 0;
@@ -1196,9 +1201,16 @@ static bitmap_counter_t *bitmap_get_coun
}
}
-int bitmap_startwrite(struct bitmap *bitmap, sector_t offset, unsigned long sectors)
+int bitmap_startwrite(struct bitmap *bitmap, sector_t offset, unsigned long sectors, int async)
{
if (!bitmap) return 0;
+
+ if (async) {
+ atomic_inc(&bitmap->async_writes);
+ PRINTK(KERN_DEBUG "inc async write count %d/%d\n",
+ atomic_read(&bitmap->async_writes), bitmap->async_max_writes);
+ }
+
while (sectors) {
int blocks;
bitmap_counter_t *bmc;
@@ -1233,9 +1245,15 @@ int bitmap_startwrite(struct bitmap *bit
}
void bitmap_endwrite(struct bitmap *bitmap, sector_t offset, unsigned long sectors,
- int success)
+ int success, int async)
{
if (!bitmap) return;
+ if (async) {
+ atomic_dec(&bitmap->async_writes);
+ PRINTK(KERN_DEBUG "dec async write count %d/%d\n",
+ atomic_read(&bitmap->async_writes), bitmap->async_max_writes);
+ }
+
while (sectors) {
int blocks;
unsigned long flags;
diff -purN --exclude core --exclude-from /export/public/clemep/tmp/dontdiff linux-2.6.11-rc3-mm2-patch-all-write-mostly-max-dev-bug-bitmap-bug-fix/drivers/md/md.c linux-2.6.11-rc3-mm2-patch-all-write-mostly-async-write-bitmap-bug-fix/drivers/md/md.c
--- linux-2.6.11-rc3-mm2-patch-all-write-mostly-max-dev-bug-bitmap-bug-fix/drivers/md/md.c Mon Feb 21 14:22:21 2005
+++ linux-2.6.11-rc3-mm2-patch-all-write-mostly-async-write-bitmap-bug-fix/drivers/md/md.c Fri Mar 4 13:37:57 2005
@@ -2166,6 +2166,8 @@ static int get_disk_info(mddev_t * mddev
info.state |= (1<<MD_DISK_ACTIVE);
info.state |= (1<<MD_DISK_SYNC);
}
+ if (test_bit(WriteMostly, &rdev->flags))
+ info.state |= (1<<MD_DISK_WRITEONLY);
} else {
info.major = info.minor = 0;
info.raid_disk = -1;
@@ -2411,6 +2413,10 @@ static int hot_add_disk(mddev_t * mddev,
goto abort_unbind_export;
}
+ if (mddev->bitmap && mddev->bitmap->async_max_writes)
+ /* array is async, hotadd = write only */
+ set_bit(WriteMostly, &rdev->flags);
+
rdev->raid_disk = -1;
md_update_sb(mddev);
@@ -3290,6 +3296,8 @@ static int md_seq_show(struct seq_file *
char b[BDEVNAME_SIZE];
seq_printf(seq, " %s[%d]",
bdevname(rdev->bdev,b), rdev->desc_nr);
+ if (test_bit(WriteMostly, &rdev->flags))
+ seq_printf(seq, "(W)");
if (rdev->faulty) {
seq_printf(seq, "(F)");
continue;
@@ -3339,6 +3347,11 @@ static int md_seq_show(struct seq_file *
seq_printf(seq, "\n");
spin_unlock_irqrestore(&bitmap->lock, flags);
kfree(buf);
+ if (bitmap->async_max_writes)
+ seq_printf(seq,
+ " async: %d/%ld outstanding writes\n",
+ atomic_read(&bitmap->async_writes),
+ bitmap->async_max_writes);
}
seq_printf(seq, "\n");
diff -purN --exclude core --exclude-from /export/public/clemep/tmp/dontdiff linux-2.6.11-rc3-mm2-patch-all-write-mostly-max-dev-bug-bitmap-bug-fix/include/linux/raid/bitmap.h linux-2.6.11-rc3-mm2-patch-all-write-mostly-async-write-bitmap-bug-fix/include/linux/raid/bitmap.h
--- linux-2.6.11-rc3-mm2-patch-all-write-mostly-max-dev-bug-bitmap-bug-fix/include/linux/raid/bitmap.h Fri Feb 18 14:45:25 2005
+++ linux-2.6.11-rc3-mm2-patch-all-write-mostly-async-write-bitmap-bug-fix/include/linux/raid/bitmap.h Thu Mar 10 11:39:37 2005
@@ -6,8 +6,8 @@
#ifndef BITMAP_H
#define BITMAP_H 1
-#define BITMAP_MAJOR 3
-#define BITMAP_MINOR 38
+#define BITMAP_MAJOR 4
+#define BITMAP_MINOR 0
/*
* in-memory bitmap:
@@ -147,8 +147,9 @@ typedef struct bitmap_super_s {
__u32 state; /* 48 bitmap state information */
__u32 chunksize; /* 52 the bitmap chunk size in bytes */
__u32 daemon_sleep; /* 56 seconds between disk flushes */
+ __u32 async_writes; /* 60 number of outstanding async writes */
- __u8 pad[256 - 60]; /* set to zero */
+ __u8 pad[256 - 64]; /* set to zero */
} bitmap_super_t;
/* notes:
@@ -225,6 +226,9 @@ struct bitmap {
unsigned long flags;
+ unsigned long async_max_writes; /* asynchronous write mode */
+ atomic_t async_writes;
+
/*
* the bitmap daemon - periodically wakes up and sweeps the bitmap
* file, cleaning up bits and flushing out pages to disk as necessary
@@ -266,9 +270,10 @@ int bitmap_update_sb(struct bitmap *bitm
int bitmap_setallbits(struct bitmap *bitmap);
/* these are exported */
-int bitmap_startwrite(struct bitmap *bitmap, sector_t offset, unsigned long sectors);
-void bitmap_endwrite(struct bitmap *bitmap, sector_t offset, unsigned long sectors,
- int success);
+int bitmap_startwrite(struct bitmap *bitmap, sector_t offset,
+ unsigned long sectors, int async);
+void bitmap_endwrite(struct bitmap *bitmap, sector_t offset,
+ unsigned long sectors, int success, int async);
int bitmap_start_sync(struct bitmap *bitmap, sector_t offset, int *blocks);
void bitmap_end_sync(struct bitmap *bitmap, sector_t offset, int *blocks, int aborted);
void bitmap_close_sync(struct bitmap *bitmap);
diff -purN --exclude core --exclude-from /export/public/clemep/tmp/dontdiff linux-2.6.11-rc3-mm2-patch-all-write-mostly-max-dev-bug-bitmap-bug-fix/include/linux/raid/md_k.h linux-2.6.11-rc3-mm2-patch-all-write-mostly-async-write-bitmap-bug-fix/include/linux/raid/md_k.h
--- linux-2.6.11-rc3-mm2-patch-all-write-mostly-max-dev-bug-bitmap-bug-fix/include/linux/raid/md_k.h Fri Feb 18 14:45:47 2005
+++ linux-2.6.11-rc3-mm2-patch-all-write-mostly-async-write-bitmap-bug-fix/include/linux/raid/md_k.h Wed Feb 23 15:47:30 2005
@@ -274,6 +274,9 @@ struct mddev_s
atomic_t writes_pending;
request_queue_t *queue; /* for plugging ... */
+ atomic_t async_writes; /* outstanding async IO */
+ unsigned int async_max_writes; /* 0 = sync */
+
struct bitmap *bitmap; /* the bitmap for the device */
struct file *bitmap_file; /* the bitmap file */
