NFS: introduce mechanism for tracking NFS client metrics
Add a per-superblock performance counter facility to the NFS client. This
facility mimics the counters available for block devices and for
networking. Expose these new counters via the new /proc/self/mountstats
interface.
Thanks to Andrew Morton and Trond Myklebust for their review and comments.
Test plan:
fsx and iozone on UP and SMP systems, with and without pre-emption. Watch
for memory overwrite bugs, and performance loss (significantly more CPU
required per op).
Signed-off-by: Chuck Lever <cel@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
diff --git a/fs/nfs/inode.c b/fs/nfs/inode.c
index 827d692..86b756f 100644
--- a/fs/nfs/inode.c
+++ b/fs/nfs/inode.c
@@ -42,6 +42,7 @@
#include "nfs4_fs.h"
#include "callback.h"
#include "delegation.h"
+#include "iostat.h"
#define NFSDBG_FACILITY NFSDBG_VFS
#define NFS_PARANOIA 1
@@ -65,6 +66,7 @@
static void nfs_umount_begin(struct super_block *);
static int nfs_statfs(struct super_block *, struct kstatfs *);
static int nfs_show_options(struct seq_file *, struct vfsmount *);
+static int nfs_show_stats(struct seq_file *, struct vfsmount *);
static void nfs_zap_acl_cache(struct inode *);
static struct rpc_program nfs_program;
@@ -78,6 +80,7 @@
.clear_inode = nfs_clear_inode,
.umount_begin = nfs_umount_begin,
.show_options = nfs_show_options,
+ .show_stats = nfs_show_stats,
};
/*
@@ -290,6 +293,12 @@
}
sb->s_root->d_op = server->rpc_ops->dentry_ops;
+ server->io_stats = nfs_alloc_iostats();
+ if (!server->io_stats) {
+ no_root_error = -ENOMEM;
+ goto out_no_root;
+ }
+
/* Get some general file system info */
if (server->namelen == 0 &&
server->rpc_ops->pathconf(server, &server->fh, &pathinfo) >= 0)
@@ -582,7 +591,7 @@
}
-static int nfs_show_options(struct seq_file *m, struct vfsmount *mnt)
+static void nfs_show_mount_options(struct seq_file *m, struct nfs_server *nfss, int showdefaults)
{
static struct proc_nfs_info {
int flag;
@@ -598,20 +607,19 @@
{ 0, NULL, NULL }
};
struct proc_nfs_info *nfs_infop;
- struct nfs_server *nfss = NFS_SB(mnt->mnt_sb);
char buf[12];
char *proto;
seq_printf(m, ",vers=%d", nfss->rpc_ops->version);
seq_printf(m, ",rsize=%d", nfss->rsize);
seq_printf(m, ",wsize=%d", nfss->wsize);
- if (nfss->acregmin != 3*HZ)
+ if (nfss->acregmin != 3*HZ || showdefaults)
seq_printf(m, ",acregmin=%d", nfss->acregmin/HZ);
- if (nfss->acregmax != 60*HZ)
+ if (nfss->acregmax != 60*HZ || showdefaults)
seq_printf(m, ",acregmax=%d", nfss->acregmax/HZ);
- if (nfss->acdirmin != 30*HZ)
+ if (nfss->acdirmin != 30*HZ || showdefaults)
seq_printf(m, ",acdirmin=%d", nfss->acdirmin/HZ);
- if (nfss->acdirmax != 60*HZ)
+ if (nfss->acdirmax != 60*HZ || showdefaults)
seq_printf(m, ",acdirmax=%d", nfss->acdirmax/HZ);
for (nfs_infop = nfs_info; nfs_infop->flag; nfs_infop++) {
if (nfss->flags & nfs_infop->flag)
@@ -633,8 +641,89 @@
seq_printf(m, ",proto=%s", proto);
seq_printf(m, ",timeo=%lu", 10U * nfss->retrans_timeo / HZ);
seq_printf(m, ",retrans=%u", nfss->retrans_count);
+}
+
+static int nfs_show_options(struct seq_file *m, struct vfsmount *mnt)
+{
+ struct nfs_server *nfss = NFS_SB(mnt->mnt_sb);
+
+ nfs_show_mount_options(m, nfss, 0);
+
seq_puts(m, ",addr=");
seq_escape(m, nfss->hostname, " \t\n\\");
+
+ return 0;
+}
+
+static int nfs_show_stats(struct seq_file *m, struct vfsmount *mnt)
+{
+ int i, cpu;
+ struct nfs_server *nfss = NFS_SB(mnt->mnt_sb);
+ struct rpc_auth *auth = nfss->client->cl_auth;
+ struct nfs_iostats totals = { };
+
+ seq_printf(m, "statvers=%s", NFS_IOSTAT_VERS);
+
+ /*
+ * Display all mount option settings
+ */
+ seq_printf(m, "\n\topts:\t");
+ seq_puts(m, mnt->mnt_sb->s_flags & MS_RDONLY ? "ro" : "rw");
+ seq_puts(m, mnt->mnt_sb->s_flags & MS_SYNCHRONOUS ? ",sync" : "");
+ seq_puts(m, mnt->mnt_sb->s_flags & MS_NOATIME ? ",noatime" : "");
+ seq_puts(m, mnt->mnt_sb->s_flags & MS_NODIRATIME ? ",nodiratime" : "");
+ nfs_show_mount_options(m, nfss, 1);
+
+ seq_printf(m, "\n\tcaps:\t");
+ seq_printf(m, "caps=0x%x", nfss->caps);
+ seq_printf(m, ",wtmult=%d", nfss->wtmult);
+ seq_printf(m, ",dtsize=%d", nfss->dtsize);
+ seq_printf(m, ",bsize=%d", nfss->bsize);
+ seq_printf(m, ",namelen=%d", nfss->namelen);
+
+#ifdef CONFIG_NFS_V4
+ if (nfss->rpc_ops->version == 4) {
+ seq_printf(m, "\n\tnfsv4:\t");
+ seq_printf(m, "bm0=0x%x", nfss->attr_bitmask[0]);
+ seq_printf(m, ",bm1=0x%x", nfss->attr_bitmask[1]);
+ seq_printf(m, ",acl=0x%x", nfss->acl_bitmask);
+ }
+#endif
+
+ /*
+ * Display security flavor in effect for this mount
+ */
+ seq_printf(m, "\n\tsec:\tflavor=%d", auth->au_ops->au_flavor);
+ if (auth->au_flavor)
+ seq_printf(m, ",pseudoflavor=%d", auth->au_flavor);
+
+ /*
+ * Display superblock I/O counters
+ */
+ for (cpu = 0; cpu < NR_CPUS; cpu++) {
+ struct nfs_iostats *stats;
+
+ if (!cpu_possible(cpu))
+ continue;
+
+ preempt_disable();
+ stats = per_cpu_ptr(nfss->io_stats, cpu);
+
+ for (i = 0; i < __NFSIOS_COUNTSMAX; i++)
+ totals.events[i] += stats->events[i];
+ for (i = 0; i < __NFSIOS_BYTESMAX; i++)
+ totals.bytes[i] += stats->bytes[i];
+
+ preempt_enable();
+ }
+
+ seq_printf(m, "\n\tevents:\t");
+ for (i = 0; i < __NFSIOS_COUNTSMAX; i++)
+ seq_printf(m, "%lu ", totals.events[i]);
+ seq_printf(m, "\n\tbytes:\t");
+ for (i = 0; i < __NFSIOS_BYTESMAX; i++)
+ seq_printf(m, "%Lu ", totals.bytes[i]);
+
return 0;
}
@@ -1742,6 +1831,7 @@
.clear_inode = nfs4_clear_inode,
.umount_begin = nfs_umount_begin,
.show_options = nfs_show_options,
+ .show_stats = nfs_show_stats,
};
/*
@@ -2015,6 +2105,7 @@
out_free:
kfree(server->mnt_path);
kfree(server->hostname);
+ nfs_free_iostats(server->io_stats);
kfree(server);
return s;
}