From 36ed32f46e2aa35084fa0e6edecc3f0a6178489f Mon Sep 17 00:00:00 2001 From: Jeff Layton Date: Fri, 17 Jul 2026 07:08:55 -0400 Subject: nfsd: implement server-stats-get netlink handler Implement nfsd_nl_server_stats_get_dumpit() which exposes the NFS server statistics currently available via /proc/net/rpc/nfsd through the nfsd generic netlink family. The handler uses a dump operation to stream statistics across one or more netlink messages. The reply is divided into sections that are emitted in order: - scalar stats (reply cache, filehandle, IO, network, RPC), emitted once in the first message, then - per-version procedure counts (proc2/3/4-ops) and the NFSv4 per-operation counts (proc4ops-ops), using the per-netns vs_count arrays. cb->args[0] tracks the current section and cb->args[1] the entry index within it, so a section that does not fit in the current message is closed and resumed in the next one. This matters because the first dump message is allocated at NLMSG_GOODSIZE (a single page on most architectures) regardless of the client's receive buffer; packing every counter into one message would overflow it and fail the dump with -EMSGSIZE. Userspace merges the attributes from every message. This allows nfsstat to retrieve server statistics via netlink with a procfs fallback for older kernels. Assisted-by: LLM Signed-off-by: Jeff Layton Link: https://patch.msgid.link/20260717-exportd-netlink-v7-3-b7ce17b83b60@kernel.org Signed-off-by: Chuck Lever --- include/uapi/linux/nfsd_netlink.h | 35 +++++++++++++++++++++++++++++++++++ 1 file changed, 35 insertions(+) (limited to 'include/uapi/linux') diff --git a/include/uapi/linux/nfsd_netlink.h b/include/uapi/linux/nfsd_netlink.h index f5b75d5caba9..3d076d173b1d 100644 --- a/include/uapi/linux/nfsd_netlink.h +++ b/include/uapi/linux/nfsd_netlink.h @@ -225,6 +225,40 @@ enum { NFSD_A_UNLOCK_EXPORT_MAX = (__NFSD_A_UNLOCK_EXPORT_MAX - 1) }; +enum { + NFSD_A_SERVER_PROC_ENTRY_OP = 1, + NFSD_A_SERVER_PROC_ENTRY_COUNT, + NFSD_A_SERVER_PROC_ENTRY_PAD, + + __NFSD_A_SERVER_PROC_ENTRY_MAX, + NFSD_A_SERVER_PROC_ENTRY_MAX = (__NFSD_A_SERVER_PROC_ENTRY_MAX - 1) +}; + +enum { + NFSD_A_SERVER_STATS_RC_HITS = 1, + NFSD_A_SERVER_STATS_RC_MISSES, + NFSD_A_SERVER_STATS_RC_NOCACHE, + NFSD_A_SERVER_STATS_PAD, + NFSD_A_SERVER_STATS_FH_STALE, + NFSD_A_SERVER_STATS_IO_READ, + NFSD_A_SERVER_STATS_IO_WRITE, + NFSD_A_SERVER_STATS_NETCNT, + NFSD_A_SERVER_STATS_NETUDPCNT, + NFSD_A_SERVER_STATS_NETTCPCNT, + NFSD_A_SERVER_STATS_NETTCPCONN, + NFSD_A_SERVER_STATS_RPCCNT, + NFSD_A_SERVER_STATS_RPCBADFMT, + NFSD_A_SERVER_STATS_RPCBADAUTH, + NFSD_A_SERVER_STATS_RPCBADCLNT, + NFSD_A_SERVER_STATS_PROC2_OPS, + NFSD_A_SERVER_STATS_PROC3_OPS, + NFSD_A_SERVER_STATS_PROC4_OPS, + NFSD_A_SERVER_STATS_PROC4OPS_OPS, + + __NFSD_A_SERVER_STATS_MAX, + NFSD_A_SERVER_STATS_MAX = (__NFSD_A_SERVER_STATS_MAX - 1) +}; + enum { NFSD_CMD_RPC_STATUS_GET = 1, NFSD_CMD_THREADS_SET, @@ -244,6 +278,7 @@ enum { NFSD_CMD_UNLOCK_IP, NFSD_CMD_UNLOCK_FILESYSTEM, NFSD_CMD_UNLOCK_EXPORT, + NFSD_CMD_SERVER_STATS_GET, __NFSD_CMD_MAX, NFSD_CMD_MAX = (__NFSD_CMD_MAX - 1) -- cgit v1.2.3