diff options
| author | Alexandra Winter <wintera@linux.ibm.com> | 2025-09-18 13:04:48 +0200 |
|---|---|---|
| committer | Paolo Abeni <pabeni@redhat.com> | 2025-09-23 11:13:21 +0200 |
| commit | a4997e17d13767e67170f09bfa0b867862cad9d9 (patch) | |
| tree | 41906e5e5d5da2477c78554c4e130ddf63e6a837 | |
| parent | 884eee8e43f3072db4111178c98b9aa5c57bcf92 (diff) | |
net/smc: Decouple sf and attached send_buf in smc_loopback
Before this patch there was the following assumption in
smc_loopback.c>smc_lo_move_data():
sf (signalling flag) == 0 : data is already in an attached target dmb
sf == 1 : data is not yet in the target dmb
This is true for the 2 callers in smc client
smcd_cdc_msg_send() : sf=1
smcd_tx_rdma_writes() : sf=0
but should not be a general assumption.
Add a bool to struct smc_buf_desc to indicate whether an SMC-D sndbuf_desc
is an attached buffer. Don't call move_data() for attached send_buffers,
because it is not necessary.
Move the data in smc_lo_move_data() if len != 0 and signal when requested.
Signed-off-by: Alexandra Winter <wintera@linux.ibm.com>
Reviewed-by: Mahanta Jambigi <mjambigi@linux.ibm.com>
Reviewed-by: Dust Li <dust.li@linux.alibaba.com>
Link: https://patch.msgid.link/20250918110500.1731261-3-wintera@linux.ibm.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
| -rw-r--r-- | net/smc/smc_core.h | 5 | ||||
| -rw-r--r-- | net/smc/smc_ism.c | 1 | ||||
| -rw-r--r-- | net/smc/smc_loopback.c | 9 | ||||
| -rw-r--r-- | net/smc/smc_tx.c | 3 |
4 files changed, 12 insertions, 6 deletions
diff --git a/net/smc/smc_core.h b/net/smc/smc_core.h index 48a1b1dcb576..a5a78cbff341 100644 --- a/net/smc/smc_core.h +++ b/net/smc/smc_core.h @@ -13,6 +13,7 @@ #define _SMC_CORE_H #include <linux/atomic.h> +#include <linux/types.h> #include <linux/smc.h> #include <linux/pci.h> #include <rdma/ib_verbs.h> @@ -221,6 +222,10 @@ struct smc_buf_desc { /* virtually contiguous */ }; struct { /* SMC-D */ + /* SMC-D tx buffer */ + bool is_attached; + /* no need for explicit writes */ + /* SMC-D rx buffer: */ unsigned short sba_idx; /* SBA index number */ u64 token; diff --git a/net/smc/smc_ism.c b/net/smc/smc_ism.c index fca01b95b65a..503a9f93b392 100644 --- a/net/smc/smc_ism.c +++ b/net/smc/smc_ism.c @@ -274,6 +274,7 @@ int smc_ism_attach_dmb(struct smcd_dev *dev, u64 token, dmb_desc->cpu_addr = dmb.cpu_addr; dmb_desc->dma_addr = dmb.dma_addr; dmb_desc->len = dmb.dmb_len; + dmb_desc->is_attached = true; } return rc; } diff --git a/net/smc/smc_loopback.c b/net/smc/smc_loopback.c index 0eb00bbefd17..1853c26fbbbb 100644 --- a/net/smc/smc_loopback.c +++ b/net/smc/smc_loopback.c @@ -224,12 +224,6 @@ static int smc_lo_move_data(struct smcd_dev *smcd, u64 dmb_tok, struct smc_lo_dev *ldev = smcd->priv; struct smc_connection *conn; - if (!sf) - /* since sndbuf is merged with peer DMB, there is - * no need to copy data from sndbuf to peer DMB. - */ - return 0; - read_lock_bh(&ldev->dmb_ht_lock); hash_for_each_possible(ldev->dmb_ht, tmp_node, list, dmb_tok) { if (tmp_node->token == dmb_tok) { @@ -244,6 +238,9 @@ static int smc_lo_move_data(struct smcd_dev *smcd, u64 dmb_tok, memcpy((char *)rmb_node->cpu_addr + offset, data, size); read_unlock_bh(&ldev->dmb_ht_lock); + if (!sf) + return 0; + conn = smcd->conn[rmb_node->sba_idx]; if (!conn || conn->killed) return -EPIPE; diff --git a/net/smc/smc_tx.c b/net/smc/smc_tx.c index 214ac3cbcf9a..3144b4b1fe29 100644 --- a/net/smc/smc_tx.c +++ b/net/smc/smc_tx.c @@ -426,6 +426,9 @@ static int smcd_tx_rdma_writes(struct smc_connection *conn, size_t len, int srcchunk, dstchunk; int rc; + if (conn->sndbuf_desc->is_attached) + return 0; + for (dstchunk = 0; dstchunk < 2; dstchunk++) { for (srcchunk = 0; srcchunk < 2; srcchunk++) { void *data = conn->sndbuf_desc->cpu_addr + src_off; |