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| author | NeilBrown | 2010-06-01 11:37:29 +0200 |
|---|---|---|
| committer | NeilBrown | 2010-07-26 04:53:08 +0200 |
| commit | 2ac8740151b082f045e58010eb92560c3a23a0e9 (patch) | |
| tree | 39bff686e28f033339c6d1cf47042b6dc1586c2f /drivers/md/md.h | |
| parent | md/raid5: export is_congested test (diff) | |
| download | kernel-qcow2-linux-2ac8740151b082f045e58010eb92560c3a23a0e9.tar.gz kernel-qcow2-linux-2ac8740151b082f045e58010eb92560c3a23a0e9.tar.xz kernel-qcow2-linux-2ac8740151b082f045e58010eb92560c3a23a0e9.zip | |
md/raid5: add simple plugging infrastructure.
md/raid5 uses the plugging infrastructure provided by the block layer
and 'struct request_queue'. However when we plug raid5 under dm there
is no request queue so we cannot use that.
So create a similar infrastructure that is much lighter weight and use
it for raid5.
Signed-off-by: NeilBrown <neilb@suse.de>
Diffstat (limited to 'drivers/md/md.h')
| -rw-r--r-- | drivers/md/md.h | 20 |
1 files changed, 20 insertions, 0 deletions
diff --git a/drivers/md/md.h b/drivers/md/md.h index c88b04745e85..5be0d6921b9d 100644 --- a/drivers/md/md.h +++ b/drivers/md/md.h @@ -29,6 +29,26 @@ typedef struct mddev_s mddev_t; typedef struct mdk_rdev_s mdk_rdev_t; +/* generic plugging support - like that provided with request_queue, + * but does not require a request_queue + */ +struct plug_handle { + void (*unplug_fn)(struct plug_handle *); + struct timer_list unplug_timer; + struct work_struct unplug_work; + unsigned long unplug_flag; +}; +#define PLUGGED_FLAG 1 +void plugger_init(struct plug_handle *plug, + void (*unplug_fn)(struct plug_handle *)); +void plugger_set_plug(struct plug_handle *plug); +int plugger_remove_plug(struct plug_handle *plug); +static inline void plugger_flush(struct plug_handle *plug) +{ + del_timer_sync(&plug->unplug_timer); + cancel_work_sync(&plug->unplug_work); +} + /* * MD's 'extended' device */ |