kernel/net/sunrpc/stats.c, branch linux-5.1.y

sunrpc: whitespace fixes

2018-07-31T16:53:40Z

Remove trailing whitespace and blank line at EOF Signed-off-by: Stephen Hemminger Signed-off-by: Anna Schumaker

sunrpc: Change rpc_print_iostats to rpc_clnt_show_stats and handle rpc_clnt clones

2018-07-31T16:53:35Z

The existing rpc_print_iostats has a few shortcomings. First, the naming is not consistent with other functions in the kernel that display stats. Second, it is really displaying stats for an rpc_clnt structure as it displays both xprt stats and per-op stats. Third, it does not handle rpc_clnt clones, which is important for the one in-kernel tree caller of this function, the NFS client's nfs_show_stats function. Fix all of the above by renaming the rpc_print_iostats to rpc_clnt_show_stats and looping through any rpc_clnt clones via cl_parent. Once this interface is fixed, this addresses a problem with NFSv4. Before this patch, the /proc/self/mountstats always showed incorrect counts for NFSv4 lease and session related opcodes such as SEQUENCE, RENEW, SETCLIENTID, CREATE_SESSION, etc. These counts were always 0 even though many ops would go over the wire. The reason for this is there are multiple rpc_clnt structures allocated for any given NFSv4 mount, and inside nfs_show_stats() we callled into rpc_print_iostats() which only handled one of them, nfs_server->client. Fix these counts by calling sunrpc's new rpc_clnt_show_stats() function, which handles cloned rpc_clnt structs and prints the stats together. Note that one side-effect of the above is that multiple mounts from the same NFS server will show identical counts in the above ops due to the fact the one rpc_clnt (representing the NFSv4 client state) is shared across mounts. Signed-off-by: Dave Wysochanski Signed-off-by: Anna Schumaker

sunrpc: Add _add_rpc_iostats() to add rpc_iostats metrics

2018-07-30T17:19:41Z

Add a helper function to add the metrics in two rpc_iostats structures. Signed-off-by: Dave Wysochanski Signed-off-by: Anna Schumaker

sunrpc: add _print_rpc_iostats() to output metrics for one RPC op

2018-07-30T17:19:41Z

Refactor the output of the metrics for one RPC op into an internal function. No functional change. Signed-off-by: Dave Wysochanski Signed-off-by: Anna Schumaker

sunrpc: Add static trace point to report RPC latency stats

2018-04-10T20:06:22Z

Introduce a low-overhead mechanism to report information about latencies of individual RPCs. The goal is to enable user space to filter the trace record for latency outliers, or build histograms, etc. Signed-off-by: Chuck Lever Signed-off-by: Anna Schumaker

sunrpc: move pc_count out of struct svc_procinfo

2017-05-15T15:42:30Z

pc_count is the only writeable memeber of struct svc_procinfo, which is a good candidate to be const-ified as it contains function pointers. This patch moves it into out out struct svc_procinfo, and into a separate writable array that is pointed to by struct svc_version. Signed-off-by: Christoph Hellwig

sunrpc: mark all struct rpc_procinfo instances as const

2017-05-15T15:42:20Z

struct rpc_procinfo contains function pointers, and marking it as constant avoids it being able to be used as an attach vector for code injections. Signed-off-by: Christoph Hellwig Acked-by: Trond Myklebust

sunrpc: move p_count out of struct rpc_procinfo

2017-05-15T15:42:18Z

p_count is the only writeable memeber of struct rpc_procinfo, which is a good candidate to be const-ified as it contains function pointers. This patch moves it into out out struct rpc_procinfo, and into a separate writable array that is pointed to by struct rpc_version and indexed by p_statidx. Signed-off-by: Christoph Hellwig

SUNRPC: Proper metric accounting when RPC is not transmitted

2016-11-29T21:45:44Z

I noticed recently that during an xfstests on a krb5i mount, the retransmit count for certain operations had gone negative, and the backlog value became unreasonably large. I recall that Andy has pointed this out to me in the past. When call_refresh fails to find a valid credential for an RPC, the RPC exits immediately without sending anything on the wire. This leaves rq_ntrans, rq_xtime, and rq_rtt set to zero. The solution for om_queue is to not add the to RPC's running backlog queue total whenever rq_xtime is zero. For om_ntrans, it's a bit more difficult. A zero rq_ntrans causes om_ops to become larger than om_ntrans. The design of the RPC metrics API assumes that ntrans will always be equal to or larger than the ops count. The result is that when an RPC fails to find credentials, the RPC operation's reported retransmit count, which is computed in user space as the difference between ops and ntrans, goes negative. Ideally the kernel API should report a separate retransmit and "exited before initial transmission" metric, so that user space can sort out the difference properly. To avoid kernel API changes and changes to the way rq_ntrans is used when performing transport locking, account for untransmitted RPCs so that om_ntrans keeps up with om_ops: always add one or more to om_ntrans. Signed-off-by: Chuck Lever Signed-off-by: Anna Schumaker

sunrpc: add rpc_count_iostats_idx

2015-02-03T19:06:38Z

Add a call to tally stats for a task under a different statsidx than what's contained in the task structure. This is needed to properly account for pnfs reads/writes when the DS nfs version != the MDS version. Signed-off-by: Weston Andros Adamson Signed-off-by: Tom Haynes