summaryrefslogtreecommitdiff
path: root/fs/cachefiles/proc.c
diff options
context:
space:
mode:
authorLinus Torvalds <torvalds@linux-foundation.org>2009-04-03 10:07:43 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2009-04-03 10:07:43 -0700
commit3cc50ac0dbda5100684e570247782330155d35e0 (patch)
treef4b8f22d1725ebe65d2fe658d292dabacd7ed564 /fs/cachefiles/proc.c
parentd9b9be024a6628a01d8730d1fd0b5f25658a2794 (diff)
parentb797cac7487dee6bfddeb161631c1bbc54fa3cdb (diff)
Merge git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-2.6-fscache
* git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-2.6-fscache: (41 commits) NFS: Add mount options to enable local caching on NFS NFS: Display local caching state NFS: Store pages from an NFS inode into a local cache NFS: Read pages from FS-Cache into an NFS inode NFS: nfs_readpage_async() needs to be accessible as a fallback for local caching NFS: Add read context retention for FS-Cache to call back with NFS: FS-Cache page management NFS: Add some new I/O counters for FS-Cache doing things for NFS NFS: Invalidate FsCache page flags when cache removed NFS: Use local disk inode cache NFS: Define and create inode-level cache objects NFS: Define and create superblock-level objects NFS: Define and create server-level objects NFS: Register NFS for caching and retrieve the top-level index NFS: Permit local filesystem caching to be enabled for NFS NFS: Add FS-Cache option bit and debug bit NFS: Add comment banners to some NFS functions FS-Cache: Make kAFS use FS-Cache CacheFiles: A cache that backs onto a mounted filesystem CacheFiles: Export things for CacheFiles ...
Diffstat (limited to 'fs/cachefiles/proc.c')
-rw-r--r--fs/cachefiles/proc.c134
1 files changed, 134 insertions, 0 deletions
diff --git a/fs/cachefiles/proc.c b/fs/cachefiles/proc.c
new file mode 100644
index 000000000000..eccd33941199
--- /dev/null
+++ b/fs/cachefiles/proc.c
@@ -0,0 +1,134 @@
+/* CacheFiles statistics
+ *
+ * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved.
+ * Written by David Howells (dhowells@redhat.com)
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public Licence
+ * as published by the Free Software Foundation; either version
+ * 2 of the Licence, or (at your option) any later version.
+ */
+
+#include <linux/module.h>
+#include <linux/proc_fs.h>
+#include <linux/seq_file.h>
+#include "internal.h"
+
+atomic_t cachefiles_lookup_histogram[HZ];
+atomic_t cachefiles_mkdir_histogram[HZ];
+atomic_t cachefiles_create_histogram[HZ];
+
+/*
+ * display the latency histogram
+ */
+static int cachefiles_histogram_show(struct seq_file *m, void *v)
+{
+ unsigned long index;
+ unsigned x, y, z, t;
+
+ switch ((unsigned long) v) {
+ case 1:
+ seq_puts(m, "JIFS SECS LOOKUPS MKDIRS CREATES\n");
+ return 0;
+ case 2:
+ seq_puts(m, "===== ===== ========= ========= =========\n");
+ return 0;
+ default:
+ index = (unsigned long) v - 3;
+ x = atomic_read(&cachefiles_lookup_histogram[index]);
+ y = atomic_read(&cachefiles_mkdir_histogram[index]);
+ z = atomic_read(&cachefiles_create_histogram[index]);
+ if (x == 0 && y == 0 && z == 0)
+ return 0;
+
+ t = (index * 1000) / HZ;
+
+ seq_printf(m, "%4lu 0.%03u %9u %9u %9u\n", index, t, x, y, z);
+ return 0;
+ }
+}
+
+/*
+ * set up the iterator to start reading from the first line
+ */
+static void *cachefiles_histogram_start(struct seq_file *m, loff_t *_pos)
+{
+ if ((unsigned long long)*_pos >= HZ + 2)
+ return NULL;
+ if (*_pos == 0)
+ *_pos = 1;
+ return (void *)(unsigned long) *_pos;
+}
+
+/*
+ * move to the next line
+ */
+static void *cachefiles_histogram_next(struct seq_file *m, void *v, loff_t *pos)
+{
+ (*pos)++;
+ return (unsigned long long)*pos > HZ + 2 ?
+ NULL : (void *)(unsigned long) *pos;
+}
+
+/*
+ * clean up after reading
+ */
+static void cachefiles_histogram_stop(struct seq_file *m, void *v)
+{
+}
+
+static const struct seq_operations cachefiles_histogram_ops = {
+ .start = cachefiles_histogram_start,
+ .stop = cachefiles_histogram_stop,
+ .next = cachefiles_histogram_next,
+ .show = cachefiles_histogram_show,
+};
+
+/*
+ * open "/proc/fs/cachefiles/XXX" which provide statistics summaries
+ */
+static int cachefiles_histogram_open(struct inode *inode, struct file *file)
+{
+ return seq_open(file, &cachefiles_histogram_ops);
+}
+
+static const struct file_operations cachefiles_histogram_fops = {
+ .owner = THIS_MODULE,
+ .open = cachefiles_histogram_open,
+ .read = seq_read,
+ .llseek = seq_lseek,
+ .release = seq_release,
+};
+
+/*
+ * initialise the /proc/fs/cachefiles/ directory
+ */
+int __init cachefiles_proc_init(void)
+{
+ _enter("");
+
+ if (!proc_mkdir("fs/cachefiles", NULL))
+ goto error_dir;
+
+ if (!proc_create("fs/cachefiles/histogram", S_IFREG | 0444, NULL,
+ &cachefiles_histogram_fops))
+ goto error_histogram;
+
+ _leave(" = 0");
+ return 0;
+
+error_histogram:
+ remove_proc_entry("fs/cachefiles", NULL);
+error_dir:
+ _leave(" = -ENOMEM");
+ return -ENOMEM;
+}
+
+/*
+ * clean up the /proc/fs/cachefiles/ directory
+ */
+void cachefiles_proc_cleanup(void)
+{
+ remove_proc_entry("fs/cachefiles/histogram", NULL);
+ remove_proc_entry("fs/cachefiles", NULL);
+}