linux/net/sunrpc/xprtrdma
Chuck Lever 0dabe948f2 svcrdma: Avoid DMA mapping small RPC Replies
On some platforms, DMA mapping part of a page is more costly than
copying bytes. Indeed, not involving the I/O MMU can help the
RPC/RDMA transport scale better for tiny I/Os across more RDMA
devices. This is because interaction with the I/O MMU is eliminated
for each of these small I/Os. Without the explicit unmapping, the
NIC no longer needs to do a costly internal TLB shoot down for
buffers that are just a handful of bytes.

Since pull-up is now a more a frequent operation, I've introduced a
trace point in the pull-up path. It can be used for debugging or
user-space tools that count pull-up frequency.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2020-03-16 12:04:33 -04:00
..
backchannel.c xprtrdma: Allocate and map transport header buffers at connect time 2020-01-15 10:54:32 -05:00
frwr_ops.c xprtrdma: Fix DMA scatter-gather list mapping imbalance 2020-02-13 15:35:33 -05:00
Makefile xprtrdma: Remove support for FMR memory registration 2019-01-02 12:05:17 -05:00
module.c NFS client updates for Linux 4.18 2018-06-12 10:09:03 -07:00
rpc_rdma.c SUNRPC: Add encoders for list item discriminators 2020-03-16 12:04:32 -04:00
svc_rdma_backchannel.c svcrdma: Fix double sync of transport header buffer 2020-03-16 12:04:33 -04:00
svc_rdma_recvfrom.c svcrdma: Fix double sync of transport header buffer 2020-03-16 12:04:33 -04:00
svc_rdma_rw.c svcrdma: Rename svcrdma_encode trace points in send routines 2020-03-16 12:04:32 -04:00
svc_rdma_sendto.c svcrdma: Avoid DMA mapping small RPC Replies 2020-03-16 12:04:33 -04:00
svc_rdma_transport.c svcrdma: Remove svcrdma_cm_event() trace point 2020-03-16 12:04:32 -04:00
svc_rdma.c svcrdma: Remove svc_rdma_wq 2019-08-19 10:59:28 -04:00
transport.c xprtrdma: Eliminate per-transport "max pages" 2020-01-15 10:54:32 -05:00
verbs.c xprtrdma: DMA map rr_rdma_buf as each rpcrdma_rep is created 2020-01-15 10:54:32 -05:00
xprt_rdma.h xprtrdma: Allocate and map transport header buffers at connect time 2020-01-15 10:54:32 -05:00