This is a series of fixes and architectural changes that should
improve robustness and result in better scalability of NFS/RDMA.
The fundamental observation is that the RPC work queues are BOUND,
thus rescheduling work in the Receive completion handler to one of
these work queues just forces it to run later on the same CPU. So
try to do more work right in the Receive completion handler to
reduce context switch overhead.
A secondary concern is that the average amount of wall-clock time
it takes to handle a single Receive completion caps the IOPS rate
(both per-xprt and per-NIC). In this patch series I've taken a few
steps to reduce that latency, and I'm looking into a few others.
This series can be fetched from:
git://git.linux-nfs.org/projects/cel/cel-2.6.git
in topic branch "nfs-for-5.3".
Changes since RFC:
* Rebased on v5.2-rc4
* Clarified some patch descriptions and comments
* Addressed Anna's compiler warning in frwr_unmap_[a]sync
* Cross-ported recent xs_connect changes to xprt_rdma_connect
* Fixed several trace-event bugs
---
Chuck Lever (19):
xprtrdma: Fix a BUG when tracing is enabled with NFSv4.1 on RDMA
xprtrdma: Fix use-after-free in rpcrdma_post_recvs
xprtrdma: Replace use of xdr_stream_pos in rpcrdma_marshal_req
xprtrdma: Fix occasional transport deadlock
xprtrdma: Remove the RPCRDMA_REQ_F_PENDING flag
xprtrdma: Remove fr_state
xprtrdma: Add mechanism to place MRs back on the free list
xprtrdma: Reduce context switching due to Local Invalidation
xprtrdma: Wake RPCs directly in rpcrdma_wc_send path
xprtrdma: Simplify rpcrdma_rep_create
xprtrdma: Streamline rpcrdma_post_recvs
xprtrdma: Refactor chunk encoding
xprtrdma: Remove rpcrdma_req::rl_buffer
xprtrdma: Modernize ops->connect
NFS4: Add a trace event to record invalid CB sequence IDs
NFS: Fix show_nfs_errors macros again
NFS: Display symbolic status code names in trace log
NFS: Update symbolic flags displayed by trace events
NFS: Record task, client ID, and XID in xdr_status trace points
fs/nfs/callback_proc.c | 28 ++-
fs/nfs/nfs2xdr.c | 2
fs/nfs/nfs3xdr.c | 2
fs/nfs/nfs4trace.h | 165 +++++++++++++-------
fs/nfs/nfs4xdr.c | 2
fs/nfs/nfstrace.h | 181 ++++++++++++++++------
include/linux/sunrpc/xprt.h | 3
include/trace/events/rpcrdma.h | 90 ++++++++---
net/sunrpc/sched.c | 1
net/sunrpc/xprt.c | 32 ++++
net/sunrpc/xprtrdma/frwr_ops.c | 327 ++++++++++++++++++++++++++-------------
net/sunrpc/xprtrdma/rpc_rdma.c | 148 ++++++++----------
net/sunrpc/xprtrdma/transport.c | 83 ++++++++--
net/sunrpc/xprtrdma/verbs.c | 115 ++++++--------
net/sunrpc/xprtrdma/xprt_rdma.h | 44 +----
net/sunrpc/xprtsock.c | 23 ---
16 files changed, 776 insertions(+), 470 deletions(-)
--
Chuck Lever
