diff options
| author | Guangguan Wang <guangguan.wang@linux.alibaba.com> | 2022-07-14 17:44:01 +0800 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2022-07-18 11:19:17 +0100 |
| commit | 0ef69e788411cba2af017db731a9fc62d255e9ac (patch) | |
| tree | 4eef442d258216d382747071b839592992519931 /net/smc/smc_core.c | |
| parent | 6d52e2de6415b7a035b3e8dc4ccffd0da25bbfb9 (diff) | |
net/smc: optimize for smc_sndbuf_sync_sg_for_device and smc_rmb_sync_sg_for_cpu
Some CPU, such as Xeon, can guarantee DMA cache coherency.
So it is no need to use dma sync APIs to flush cache on such CPUs.
In order to avoid calling dma sync APIs on the IO path, use the
dma_need_sync to check whether smc_buf_desc needs dma sync when
creating smc_buf_desc.
Signed-off-by: Guangguan Wang <guangguan.wang@linux.alibaba.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/smc/smc_core.c')
| -rw-r--r-- | net/smc/smc_core.c | 8 |
1 files changed, 8 insertions, 0 deletions
diff --git a/net/smc/smc_core.c b/net/smc/smc_core.c index 1faa0cb661e4..fa3a7a851c60 100644 --- a/net/smc/smc_core.c +++ b/net/smc/smc_core.c @@ -2016,6 +2016,9 @@ static int smcr_buf_map_link(struct smc_buf_desc *buf_desc, bool is_rmb, goto free_table; } + buf_desc->is_dma_need_sync |= + smc_ib_is_sg_need_sync(lnk, buf_desc) << lnk->link_idx; + /* create a new memory region for the RMB */ if (is_rmb) { rc = smc_ib_get_memory_region(lnk->roce_pd, @@ -2234,6 +2237,7 @@ static int __smc_buf_create(struct smc_sock *smc, bool is_smcd, bool is_rmb) /* check for reusable slot in the link group */ buf_desc = smc_buf_get_slot(bufsize_short, lock, buf_list); if (buf_desc) { + buf_desc->is_dma_need_sync = 0; SMC_STAT_RMB_SIZE(smc, is_smcd, is_rmb, bufsize); SMC_STAT_BUF_REUSE(smc, is_smcd, is_rmb); break; /* found reusable slot */ @@ -2292,6 +2296,8 @@ static int __smc_buf_create(struct smc_sock *smc, bool is_smcd, bool is_rmb) void smc_sndbuf_sync_sg_for_device(struct smc_connection *conn) { + if (!conn->sndbuf_desc->is_dma_need_sync) + return; if (!smc_conn_lgr_valid(conn) || conn->lgr->is_smcd || !smc_link_active(conn->lnk)) return; @@ -2302,6 +2308,8 @@ void smc_rmb_sync_sg_for_cpu(struct smc_connection *conn) { int i; + if (!conn->rmb_desc->is_dma_need_sync) + return; if (!smc_conn_lgr_valid(conn) || conn->lgr->is_smcd) return; for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) { |