NFS: add hooks to account for NFSERR_JUKEBOX errors

Make an inode or an nfs_server struct available in the logic that handles
JUKEBOX/DELAY type errors so the NFS client can account for them.

This patch is split out from the main nfs iostat patch to highlight minor
architectural changes required to support this statistic.

Test plan:
None.

Signed-off-by: Chuck Lever <cel@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

1 files changed, 15 insertions, 4 deletions

diff --git a/fs/nfs/iostat.h b/fs/nfs/iostat.h
index dc080e5..7a74951 100644
--- a/fs/nfs/iostat.h
+++ b/fs/nfs/iostat.h
@@ -103,6 +103,7 @@ enum nfs_stat_eventcounters {
 	NFSIOS_SILLYRENAME,
 	NFSIOS_SHORTREAD,
 	NFSIOS_SHORTWRITE,
+	NFSIOS_DELAY,
 	__NFSIOS_COUNTSMAX,
 };
 
@@ -116,28 +117,38 @@ struct nfs_iostats {
 	unsigned long		events[__NFSIOS_COUNTSMAX];
 } ____cacheline_aligned;
 
-static inline void nfs_inc_stats(struct inode *inode, enum nfs_stat_eventcounters stat)
+static inline void nfs_inc_server_stats(struct nfs_server *server, enum nfs_stat_eventcounters stat)
 {
 	struct nfs_iostats *iostats;
 	int cpu;
 
 	cpu = get_cpu();
-	iostats = per_cpu_ptr(NFS_SERVER(inode)->io_stats, cpu);
+	iostats = per_cpu_ptr(server->io_stats, cpu);
 	iostats->events[stat] ++;
 	put_cpu_no_resched();
 }
 
-static inline void nfs_add_stats(struct inode *inode, enum nfs_stat_bytecounters stat, unsigned long addend)
+static inline void nfs_inc_stats(struct inode *inode, enum nfs_stat_eventcounters stat)
+{
+	nfs_inc_server_stats(NFS_SERVER(inode), stat);
+}
+
+static inline void nfs_add_server_stats(struct nfs_server *server, enum nfs_stat_bytecounters stat, unsigned long addend)
 {
 	struct nfs_iostats *iostats;
 	int cpu;
 
 	cpu = get_cpu();
-	iostats = per_cpu_ptr(NFS_SERVER(inode)->io_stats, cpu);
+	iostats = per_cpu_ptr(server->io_stats, cpu);
 	iostats->bytes[stat] += addend;
 	put_cpu_no_resched();
 }
 
+static inline void nfs_add_stats(struct inode *inode, enum nfs_stat_bytecounters stat, unsigned long addend)
+{
+	nfs_add_server_stats(NFS_SERVER(inode), stat, addend);
+}
+
 static inline struct nfs_iostats *nfs_alloc_iostats(void)
 {
 	return alloc_percpu(struct nfs_iostats);