diff options
| author |   Chuck Lever <chuck.lever@oracle.com> | 2014-11-08 20:15:09 -0500 |
|---|---|---|
| committer |   Anna Schumaker <Anna.Schumaker@Netapp.com> | 2014-11-25 16:22:15 -0500 |
| commit | edef1297f33a4546559d905457b435a5ea160bab (patch) | |
| tree | c14a3b6d62e72cb8b46a3a8cc09679b343831b49 /include/linux/sunrpc | |
| parent | Linux 3.18-rc6 (diff) | |
| download | linux-dev-edef1297f33a4546559d905457b435a5ea160bab.tar.xz linux-dev-edef1297f33a4546559d905457b435a5ea160bab.zip | |
SUNRPC: serialize iostats updates
Occasionally mountstats reports a negative retransmission rate.
Ensure that two RPCs completing concurrently don't confuse the sums
in the transport's op_metrics array.
Since pNFS filelayout can invoke rpc_count_iostats() on another
transport from xprt_release(), we can't rely on simply holding the
transport_lock in xprt_release(). There's nothing for it but hard
serialization. One spin lock per RPC operation should make this as
painless as it can be.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Diffstat (limited to 'include/linux/sunrpc')
| -rw-r--r-- | include/linux/sunrpc/metrics.h | 3 |
1 files changed, 3 insertions, 0 deletions
diff --git a/include/linux/sunrpc/metrics.h b/include/linux/sunrpc/metrics.h index 1565bbe86d51..eecb5a71e6c0 100644 --- a/include/linux/sunrpc/metrics.h +++ b/include/linux/sunrpc/metrics.h @@ -27,10 +27,13 @@ #include <linux/seq_file.h> #include <linux/ktime.h> +#include <linux/spinlock.h> #define RPC_IOSTATS_VERS "1.0" struct rpc_iostats { + spinlock_t om_lock; + /* * These counters give an idea about how many request * transmissions are required, on average, to complete that |