I tested commit 43042b90ca ("svcrdma: Reduce Receive doorbell
rate") with mlx4 (IB) and software iWARP and didn't find any
issues. However, I recently got my hardware iWARP setup back on
line (FastLinQ) and it's crashing hard on this commit (confirmed
via bisect).
The failure mode is complex.
- After a connection is established, the first Receive completes
normally.
- But the second and third Receives have garbage in their Receive
buffers. The server responds with ERR_VERS as a result.
- When the client tears down the connection to retry, a couple
of posted Receives flush twice, and that corrupts the recv_ctxt
free list.
- __svc_rdma_free then faults or loops infinitely while destroying
the xprt's recv_ctxts.
Since 43042b90ca ("svcrdma: Reduce Receive doorbell rate") does
not fix a bug but is a scalability enhancement, it's safe and
appropriate to revert it while working on a replacement.
Fixes: 43042b90ca ("svcrdma: Reduce Receive doorbell rate")
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Pull more nfsd updates from Chuck Lever:
"Here are a few additional NFSD commits for the merge window:
Optimization:
- Cork the socket while there are queued replies
Fixes:
- DRC shutdown ordering
- svc_rdma_accept() lockdep splat"
* tag 'nfsd-5.12-1' of git://git.kernel.org/pub/scm/linux/kernel/git/cel/linux:
SUNRPC: Further clean up svc_tcp_sendmsg()
SUNRPC: Remove redundant socket flags from svc_tcp_sendmsg()
SUNRPC: Use TCP_CORK to optimise send performance on the server
svcrdma: Hold private mutex while invoking rdma_accept()
nfsd: register pernet ops last, unregister first
Pull nfsd updates from Chuck Lever:
- Update NFSv2 and NFSv3 XDR decoding functions
- Further improve support for re-exporting NFS mounts
- Convert NFSD stats to per-CPU counters
- Add batch Receive posting to the server's RPC/RDMA transport
* tag 'nfsd-5.12' of git://git.kernel.org/pub/scm/linux/kernel/git/cel/linux: (65 commits)
nfsd: skip some unnecessary stats in the v4 case
nfs: use change attribute for NFS re-exports
NFSv4_2: SSC helper should use its own config.
nfsd: cstate->session->se_client -> cstate->clp
nfsd: simplify nfsd4_check_open_reclaim
nfsd: remove unused set_client argument
nfsd: find_cpntf_state cleanup
nfsd: refactor set_client
nfsd: rename lookup_clientid->set_client
nfsd: simplify nfsd_renew
nfsd: simplify process_lock
nfsd4: simplify process_lookup1
SUNRPC: Correct a comment
svcrdma: DMA-sync the receive buffer in svc_rdma_recvfrom()
svcrdma: Reduce Receive doorbell rate
svcrdma: Deprecate stat variables that are no longer used
svcrdma: Restore read and write stats
svcrdma: Convert rdma_stat_sq_starve to a per-CPU counter
svcrdma: Convert rdma_stat_recv to a per-CPU counter
svcrdma: Refactor svc_rdma_init() and svc_rdma_clean_up()
...
Remove duplicated helper functions to parse opaque XDR objects
and place inside new file net/sunrpc/auth_gss/auth_gss_internal.h.
In the new file carry the license and copyright from the source file
net/sunrpc/auth_gss/auth_gss.c. Finally, update the comment inside
include/linux/sunrpc/xdr.h since lockd is not the only user of
struct xdr_netobj.
Signed-off-by: Dave Wysochanski <dwysocha@redhat.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
This is similar to commit e340c2d6ef ("xprtrdma: Reduce the
doorbell rate (Receive)") which added Receive batching to the
client.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Clean up. We are not permitted to remove old proc files. Instead,
convert these variables to stubs that are only ever allowed to
display a value of zero.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Now that we have an efficient mechanism to update these two stats,
let's start maintaining them again.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Receives are frequent events. Avoid the overhead of a memory bus
lock cycle for counting a value that is hardly every used.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Clean up: The unit of XDR alignment is defined by RFC 4506,
not as part of the RPC message header. Thus it belongs in
include/linux/sunrpc/xdr.h.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
The next few patches will employ these strings to help make server-
side trace logs more human-readable. A similar technique is already
in use in kernel RPC client code.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Pull NFS client updates from Trond Myklebust:
"Highlights include:
Features:
- NFSv3: Add emulation of lookupp() to improve open_by_filehandle()
support
- A series of patches to improve readdir performance, particularly
with large directories
- Basic support for using NFS/RDMA with the pNFS files and flexfiles
drivers
- Micro-optimisations for RDMA
- RDMA tracing improvements
Bugfixes:
- Fix a long standing bug with xs_read_xdr_buf() when receiving
partial pages (Dan Aloni)
- Various fixes for getxattr and listxattr, when used over non-TCP
transports
- Fixes for containerised NFS from Sargun Dhillon
- switch nfsiod to be an UNBOUND workqueue (Neil Brown)
- READDIR should not ask for security label information if there is
no LSM policy (Olga Kornievskaia)
- Avoid using interval-based rebinding with TCP in lockd (Calum
Mackay)
- A series of RPC and NFS layer fixes to support the NFSv4.2
READ_PLUS code
- A couple of fixes for pnfs/flexfiles read failover
Cleanups:
- Various cleanups for the SUNRPC xdr code in conjunction with the
READ_PLUS fixes"
* tag 'nfs-for-5.11-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs: (90 commits)
NFS/pNFS: Fix a typo in ff_layout_resend_pnfs_read()
pNFS/flexfiles: Avoid spurious layout returns in ff_layout_choose_ds_for_read
NFSv4/pnfs: Add tracing for the deviceid cache
fs/lockd: convert comma to semicolon
NFSv4.2: fix error return on memory allocation failure
NFSv4.2/pnfs: Don't use READ_PLUS with pNFS yet
NFSv4.2: Deal with potential READ_PLUS data extent buffer overflow
NFSv4.2: Don't error when exiting early on a READ_PLUS buffer overflow
NFSv4.2: Handle hole lengths that exceed the READ_PLUS read buffer
NFSv4.2: decode_read_plus_hole() needs to check the extent offset
NFSv4.2: decode_read_plus_data() must skip padding after data segment
NFSv4.2: Ensure we always reset the result->count in decode_read_plus()
SUNRPC: When expanding the buffer, we may need grow the sparse pages
SUNRPC: Cleanup - constify a number of xdr_buf helpers
SUNRPC: Clean up open coded setting of the xdr_stream 'nwords' field
SUNRPC: _copy_to/from_pages() now check for zero length
SUNRPC: Cleanup xdr_shrink_bufhead()
SUNRPC: Fix xdr_expand_hole()
SUNRPC: Fixes for xdr_align_data()
SUNRPC: _shift_data_left/right_pages should check the shift length
...
There are a number of xdr helpers for struct xdr_buf that do not change
the structure itself. Mark those as taking const pointers for
documentation purposes.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
We do want to try to grow the buffer if possible, but if that attempt
fails, we still want to move the data and truncate the XDR message.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
The main use case right now for xdr_align_data() is to shift the page
data to the left, and in practice shrink the total XDR data buffer.
This patch ensures that we fix up the accounting for the buffer length
as we shift that data around.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
According to RFC5666, the correct netid for an IPv6 addressed RDMA
transport is "rdma6", which we've supported as a mount option since
Linux-4.7. The problem is when we try to load the module "xprtrdma6",
that will fail, since there is no modulealias of that name.
Fixes: 181342c5eb ("xprtrdma: Add rdma6 option to support NFS/RDMA IPv6")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Convert the READ_BUF macro in nfs4xdr.c from open code to instead
use the new xdr_stream-style decoders already in use by the encode
side (and by the in-kernel NFS client implementation). Once this
conversion is done, each individual NFSv4 argument decoder can be
independently cleaned up to replace these macros with C code.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
A "permanent" struct xdr_stream is allocated in struct svc_rqst so
that it is usable by all server-side decoders. A per-rqst scratch
buffer is also allocated to handle decoding XDR data items that
cross page boundaries.
To demonstrate how it will be used, add the first call site for the
new svcxdr_init_decode() API.
As an additional part of the overall conversion, add symbolic
constants for successful and failed XDR operations. Returning "0" is
overloaded. Sometimes it means something failed, but sometimes it
means success. To make it more clear when XDR decoding functions
succeed or fail, introduce symbolic constants.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
As a pre-requisite for handling multiple Read chunks in each Read
list, convert svc_rdma_recv_read_chunk() to use the new parsed Read
chunk list.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Chuck Lever
Linus Torvalds
Trond Myklebust
Dave Wysochanski