drbd: factor out drbd_rs_number_requests
Preparation patch to be able to use the auto-throttling resync controller
for online-verify requests as well.
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
diff --git a/drivers/block/drbd/drbd_worker.c b/drivers/block/drbd/drbd_worker.c
index 971e9b3..6d111c8 100644
--- a/drivers/block/drbd/drbd_worker.c
+++ b/drivers/block/drbd/drbd_worker.c
@@ -492,6 +492,32 @@
return req_sect;
}
+int drbd_rs_number_requests(struct drbd_conf *mdev)
+{
+ int number;
+ if (mdev->rs_plan_s.size) { /* mdev->sync_conf.c_plan_ahead */
+ number = drbd_rs_controller(mdev) >> (BM_BLOCK_SHIFT - 9);
+ mdev->c_sync_rate = number * HZ * (BM_BLOCK_SIZE / 1024) / SLEEP_TIME;
+ } else {
+ mdev->c_sync_rate = mdev->sync_conf.rate;
+ number = SLEEP_TIME * mdev->c_sync_rate / ((BM_BLOCK_SIZE / 1024) * HZ);
+ }
+
+ /* Throttle resync on lower level disk activity, which may also be
+ * caused by application IO on Primary/SyncTarget.
+ * Keep this after the call to drbd_rs_controller, as that assumes
+ * to be called as precisely as possible every SLEEP_TIME,
+ * and would be confused otherwise. */
+ if (number && drbd_rs_should_slow_down(mdev)) {
+ mdev->c_sync_rate = 1;
+ number = 0;
+ }
+
+ /* ignore the amount of pending requests, the resync controller should
+ * throttle down to incoming reply rate soon enough anyways. */
+ return number;
+}
+
int w_make_resync_request(struct drbd_conf *mdev,
struct drbd_work *w, int cancel)
{
@@ -499,7 +525,7 @@
sector_t sector;
const sector_t capacity = drbd_get_capacity(mdev->this_bdev);
int max_segment_size;
- int number, rollback_i, size, pe, mx;
+ int number, rollback_i, size;
int align, queued, sndbuf;
int i = 0;
@@ -537,39 +563,10 @@
mdev->agreed_pro_version < 94 ? queue_max_segment_size(mdev->rq_queue) :
mdev->agreed_pro_version < 95 ? DRBD_MAX_SIZE_H80_PACKET : DRBD_MAX_SEGMENT_SIZE;
- if (mdev->rs_plan_s.size) { /* mdev->sync_conf.c_plan_ahead */
- number = drbd_rs_controller(mdev) >> (BM_BLOCK_SHIFT - 9);
- mdev->c_sync_rate = number * HZ * (BM_BLOCK_SIZE / 1024) / SLEEP_TIME;
- } else {
- mdev->c_sync_rate = mdev->sync_conf.rate;
- number = SLEEP_TIME * mdev->c_sync_rate / ((BM_BLOCK_SIZE / 1024) * HZ);
- }
-
- /* Throttle resync on lower level disk activity, which may also be
- * caused by application IO on Primary/SyncTarget.
- * Keep this after the call to drbd_rs_controller, as that assumes
- * to be called as precisely as possible every SLEEP_TIME,
- * and would be confused otherwise. */
- if (drbd_rs_should_slow_down(mdev))
+ number = drbd_rs_number_requests(mdev);
+ if (number == 0)
goto requeue;
- mutex_lock(&mdev->data.mutex);
- if (mdev->data.socket)
- mx = mdev->data.socket->sk->sk_rcvbuf / sizeof(struct p_block_req);
- else
- mx = 1;
- mutex_unlock(&mdev->data.mutex);
-
- /* For resync rates >160MB/sec, allow more pending RS requests */
- if (number > mx)
- mx = number;
-
- /* Limit the number of pending RS requests to no more than the peer's receive buffer */
- pe = atomic_read(&mdev->rs_pending_cnt);
- if ((pe + number) > mx) {
- number = mx - pe;
- }
-
for (i = 0; i < number; i++) {
/* Stop generating RS requests, when half of the send buffer is filled */
mutex_lock(&mdev->data.mutex);