From 417fc2caef268ed23169316f6c5e3a33775bfae5 Mon Sep 17 00:00:00 2001 From: Dan Magenheimer Date: Wed, 21 Sep 2011 12:28:04 -0400 Subject: [PATCH] mm: cleancache: report statistics via debugfs instead of sysfs. [v9: akpm@linux-foundation.org: sysfs->debugfs; no longer need Doc/ABI file] Signed-off-by: Dan Magenheimer Signed-off-by: Konrad Wilk Cc: Jan Beulich Acked-by: Seth Jennings Cc: Jeremy Fitzhardinge Cc: Hugh Dickins Cc: Johannes Weiner Cc: Nitin Gupta Cc: Matthew Wilcox Cc: Chris Mason Cc: Rik Riel Cc: Andrew Morton --- .../ABI/testing/sysfs-kernel-mm-cleancache | 11 ---- Documentation/vm/cleancache.txt | 4 +- mm/cleancache.c | 68 +++++++--------------- 3 files changed, 24 insertions(+), 59 deletions(-) delete mode 100644 Documentation/ABI/testing/sysfs-kernel-mm-cleancache diff --git a/Documentation/ABI/testing/sysfs-kernel-mm-cleancache b/Documentation/ABI/testing/sysfs-kernel-mm-cleancache deleted file mode 100644 index 662ae64..0000000 --- a/Documentation/ABI/testing/sysfs-kernel-mm-cleancache +++ /dev/null @@ -1,11 +0,0 @@ -What: /sys/kernel/mm/cleancache/ -Date: April 2011 -Contact: Dan Magenheimer -Description: - /sys/kernel/mm/cleancache/ contains a number of files which - record a count of various cleancache operations - (sum across all filesystems): - succ_gets - failed_gets - puts - flushes diff --git a/Documentation/vm/cleancache.txt b/Documentation/vm/cleancache.txt index e0a5356..f726717 100644 --- a/Documentation/vm/cleancache.txt +++ b/Documentation/vm/cleancache.txt @@ -84,8 +84,8 @@ lock the page to ensure serial behavior. CLEANCACHE PERFORMANCE METRICS -Cleancache monitoring is done by sysfs files in the -/sys/kernel/mm/cleancache directory. The effectiveness of cleancache +If properly configured, monitoring of cleancache is done via debugfs in +the /sys/kernel/debug/mm/cleancache directory. The effectiveness of cleancache can be measured (across all filesystems) with: succ_gets - number of gets that were successful diff --git a/mm/cleancache.c b/mm/cleancache.c index b9c198b..deb9f2c 100644 --- a/mm/cleancache.c +++ b/mm/cleancache.c @@ -15,6 +15,7 @@ #include #include #include +#include #include /* @@ -33,11 +34,15 @@ EXPORT_SYMBOL(cleancache_enabled); */ static struct cleancache_ops cleancache_ops; -/* useful stats available in /sys/kernel/mm/cleancache */ -static unsigned long cleancache_succ_gets; -static unsigned long cleancache_failed_gets; -static unsigned long cleancache_puts; -static unsigned long cleancache_flushes; +/* + * Counters available via /sys/kernel/debug/frontswap (if debugfs is + * properly configured. These are for information only so are not protected + * against increment races. + */ +static u64 cleancache_succ_gets; +static u64 cleancache_failed_gets; +static u64 cleancache_puts; +static u64 cleancache_invalidates; /* * register operations for cleancache, returning previous thus allowing @@ -163,7 +168,7 @@ void __cleancache_invalidate_page(struct address_space *mapping, if (cleancache_get_key(mapping->host, &key) >= 0) { (*cleancache_ops.invalidate_page)(pool_id, key, page->index); - cleancache_flushes++; + cleancache_invalidates++; } } } @@ -199,48 +204,19 @@ void __cleancache_invalidate_fs(struct super_block *sb) } EXPORT_SYMBOL(__cleancache_invalidate_fs); -#ifdef CONFIG_SYSFS - -/* see Documentation/ABI/xxx/sysfs-kernel-mm-cleancache */ - -#define CLEANCACHE_SYSFS_RO(_name) \ - static ssize_t cleancache_##_name##_show(struct kobject *kobj, \ - struct kobj_attribute *attr, char *buf) \ - { \ - return sprintf(buf, "%lu\n", cleancache_##_name); \ - } \ - static struct kobj_attribute cleancache_##_name##_attr = { \ - .attr = { .name = __stringify(_name), .mode = 0444 }, \ - .show = cleancache_##_name##_show, \ - } - -CLEANCACHE_SYSFS_RO(succ_gets); -CLEANCACHE_SYSFS_RO(failed_gets); -CLEANCACHE_SYSFS_RO(puts); -CLEANCACHE_SYSFS_RO(flushes); - -static struct attribute *cleancache_attrs[] = { - &cleancache_succ_gets_attr.attr, - &cleancache_failed_gets_attr.attr, - &cleancache_puts_attr.attr, - &cleancache_flushes_attr.attr, - NULL, -}; - -static struct attribute_group cleancache_attr_group = { - .attrs = cleancache_attrs, - .name = "cleancache", -}; - -#endif /* CONFIG_SYSFS */ - static int __init init_cleancache(void) { -#ifdef CONFIG_SYSFS - int err; - - err = sysfs_create_group(mm_kobj, &cleancache_attr_group); -#endif /* CONFIG_SYSFS */ +#ifdef CONFIG_DEBUG_FS + struct dentry *root = debugfs_create_dir("cleancache", NULL); + if (root == NULL) + return -ENXIO; + debugfs_create_u64("succ_gets", S_IRUGO, root, &cleancache_succ_gets); + debugfs_create_u64("failed_gets", S_IRUGO, + root, &cleancache_failed_gets); + debugfs_create_u64("puts", S_IRUGO, root, &cleancache_puts); + debugfs_create_u64("invalidates", S_IRUGO, + root, &cleancache_invalidates); +#endif return 0; } module_init(init_cleancache) -- 2.7.4