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cifs: smbd: Only queue work for error recovery on memory registration

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It's not necessary to queue invalidated memory registration to work queue, as
all we need to do is to unmap the SG and make it usable again. This can save
CPU cycles in normal data paths as memory registration errors are rare and
normally only happens during reconnection.

Signed-off-by: Long Li <longli@microsoft.com>
Cc: stable@vger.kernel.org
Signed-off-by: Steve French <stfrench@microsoft.com>
This commit is contained in:
Long Li 2019-10-16 13:51:55 -07:00 committed by Steve French
parent 87bc2376ff
commit c21ce58eab
1 changed files with 15 additions and 11 deletions
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26
fs/cifs/smbdirect.c
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@ -2271,12 +2271,7 @@ static void smbd_mr_recovery_work(struct work_struct *work)
int rc;
list_for_each_entry(smbdirect_mr, &info->mr_list, list) {
if (smbdirect_mr->state == MR_INVALIDATED)
ib_dma_unmap_sg(
info->id->device, smbdirect_mr->sgl,
smbdirect_mr->sgl_count,
smbdirect_mr->dir);
else if (smbdirect_mr->state == MR_ERROR) {
if (smbdirect_mr->state == MR_ERROR) {
/* recover this MR entry */
rc = ib_dereg_mr(smbdirect_mr->mr);
@ -2604,11 +2599,20 @@ int smbd_deregister_mr(struct smbd_mr *smbdirect_mr)
*/
smbdirect_mr->state = MR_INVALIDATED;
/*
* Schedule the work to do MR recovery for future I/Os
* MR recovery is slow and we don't want it to block the current I/O
*/
queue_work(info->workqueue, &info->mr_recovery_work);
if (smbdirect_mr->state == MR_INVALIDATED) {
ib_dma_unmap_sg(
info->id->device, smbdirect_mr->sgl,
smbdirect_mr->sgl_count,
smbdirect_mr->dir);
smbdirect_mr->state = MR_READY;
if (atomic_inc_return(&info->mr_ready_count) == 1)
wake_up_interruptible(&info->wait_mr);
} else
/*
* Schedule the work to do MR recovery for future I/Os MR
* recovery is slow and don't want it to block current I/O
*/
queue_work(info->workqueue, &info->mr_recovery_work);
done:
if (atomic_dec_and_test(&info->mr_used_count))