From: Long Li longli@microsoft.com
commit c21ce58eab1eda4c66507897207e20c82e62a5ac upstream.
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 Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- fs/cifs/smbdirect.c | 26 +++++++++++++++----------- 1 file changed, 15 insertions(+), 11 deletions(-)
--- a/fs/cifs/smbdirect.c +++ b/fs/cifs/smbdirect.c @@ -2269,12 +2269,7 @@ static void smbd_mr_recovery_work(struct 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); @@ -2602,11 +2597,20 @@ int smbd_deregister_mr(struct smbd_mr *s */ 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))