net/smc: wait for departure of an IB message

Introduce smc_wr_tx_send_wait() to send an IB message and wait for the
tx completion event of the message. This makes sure that the message is
no longer in-flight when the function returns.

Signed-off-by: Karsten Graul <kgraul@linux.ibm.com>
Reviewed-by: Ursula Braun <ubraun@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Karsten Graul 2020-05-04 14:18:41 +02:00 committed by David S. Miller
parent b286a0651e
commit 09c61d24f9
3 changed files with 42 additions and 0 deletions

View File

@ -85,6 +85,7 @@ struct smc_link {
struct smc_rdma_sges *wr_tx_rdma_sges;/*RDMA WRITE gather meta data*/
struct smc_rdma_wr *wr_tx_rdmas; /* WR RDMA WRITE */
struct smc_wr_tx_pend *wr_tx_pends; /* WR send waiting for CQE */
struct completion *wr_tx_compl; /* WR send CQE completion */
/* above four vectors have wr_tx_cnt elements and use the same index */
dma_addr_t wr_tx_dma_addr; /* DMA address of wr_tx_bufs */
atomic_long_t wr_tx_id; /* seq # of last sent WR */

View File

@ -44,6 +44,7 @@ struct smc_wr_tx_pend { /* control data for a pending send request */
struct smc_link *link;
u32 idx;
struct smc_wr_tx_pend_priv priv;
u8 compl_requested;
};
/******************************** send queue *********************************/
@ -103,6 +104,8 @@ static inline void smc_wr_tx_process_cqe(struct ib_wc *wc)
if (pnd_snd_idx == link->wr_tx_cnt)
return;
link->wr_tx_pends[pnd_snd_idx].wc_status = wc->status;
if (link->wr_tx_pends[pnd_snd_idx].compl_requested)
complete(&link->wr_tx_compl[pnd_snd_idx]);
memcpy(&pnd_snd, &link->wr_tx_pends[pnd_snd_idx], sizeof(pnd_snd));
/* clear the full struct smc_wr_tx_pend including .priv */
memset(&link->wr_tx_pends[pnd_snd_idx], 0,
@ -275,6 +278,33 @@ int smc_wr_tx_send(struct smc_link *link, struct smc_wr_tx_pend_priv *priv)
return rc;
}
/* Send prepared WR slot via ib_post_send and wait for send completion
* notification.
* @priv: pointer to smc_wr_tx_pend_priv identifying prepared message buffer
*/
int smc_wr_tx_send_wait(struct smc_link *link, struct smc_wr_tx_pend_priv *priv,
unsigned long timeout)
{
struct smc_wr_tx_pend *pend;
int rc;
pend = container_of(priv, struct smc_wr_tx_pend, priv);
pend->compl_requested = 1;
init_completion(&link->wr_tx_compl[pend->idx]);
rc = smc_wr_tx_send(link, priv);
if (rc)
return rc;
/* wait for completion by smc_wr_tx_process_cqe() */
rc = wait_for_completion_interruptible_timeout(
&link->wr_tx_compl[pend->idx], timeout);
if (rc <= 0)
rc = -ENODATA;
if (rc > 0)
rc = 0;
return rc;
}
/* Register a memory region and wait for result. */
int smc_wr_reg_send(struct smc_link *link, struct ib_mr *mr)
{
@ -555,6 +585,8 @@ void smc_wr_free_link(struct smc_link *lnk)
void smc_wr_free_link_mem(struct smc_link *lnk)
{
kfree(lnk->wr_tx_compl);
lnk->wr_tx_compl = NULL;
kfree(lnk->wr_tx_pends);
lnk->wr_tx_pends = NULL;
kfree(lnk->wr_tx_mask);
@ -625,8 +657,15 @@ int smc_wr_alloc_link_mem(struct smc_link *link)
GFP_KERNEL);
if (!link->wr_tx_pends)
goto no_mem_wr_tx_mask;
link->wr_tx_compl = kcalloc(SMC_WR_BUF_CNT,
sizeof(link->wr_tx_compl[0]),
GFP_KERNEL);
if (!link->wr_tx_compl)
goto no_mem_wr_tx_pends;
return 0;
no_mem_wr_tx_pends:
kfree(link->wr_tx_pends);
no_mem_wr_tx_mask:
kfree(link->wr_tx_mask);
no_mem_wr_rx_sges:

View File

@ -101,6 +101,8 @@ int smc_wr_tx_put_slot(struct smc_link *link,
struct smc_wr_tx_pend_priv *wr_pend_priv);
int smc_wr_tx_send(struct smc_link *link,
struct smc_wr_tx_pend_priv *wr_pend_priv);
int smc_wr_tx_send_wait(struct smc_link *link, struct smc_wr_tx_pend_priv *priv,
unsigned long timeout);
void smc_wr_tx_cq_handler(struct ib_cq *ib_cq, void *cq_context);
void smc_wr_tx_dismiss_slots(struct smc_link *lnk, u8 wr_rx_hdr_type,
smc_wr_tx_filter filter,