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author | Mark Fasheh <mfasheh@suse.com> | 2008-07-30 05:29:18 +0400 |
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committer | Mark Fasheh <mfasheh@suse.com> | 2008-10-14 00:57:58 +0400 |
commit | 9a8ff578fb430a8816dfbc73c77e5e09c6d9c343 (patch) | |
tree | be97f570b59a4af8fbf0c4c054619193155aaaa6 /fs/ocfs2/localalloc.c | |
parent | 9c7af40b210e87f8fddd97b0badc0a352862234a (diff) | |
download | linux-9a8ff578fb430a8816dfbc73c77e5e09c6d9c343.tar.xz |
ocfs2: track local alloc state via debugfs
A per-mount debugfs file, "local_alloc" is created which when read will
expose live state of the nodes local alloc file. Performance impact is
minimal, only a bit of memory overhead per mount point. Still, the code is
hidden behind CONFIG_OCFS2_FS_STATS. This feature will help us debug
local alloc performance problems on a live system.
Signed-off-by: Mark Fasheh <mfasheh@suse.com>
Diffstat (limited to 'fs/ocfs2/localalloc.c')
-rw-r--r-- | fs/ocfs2/localalloc.c | 87 |
1 files changed, 87 insertions, 0 deletions
diff --git a/fs/ocfs2/localalloc.c b/fs/ocfs2/localalloc.c index f71658adddb5..b889f10d8090 100644 --- a/fs/ocfs2/localalloc.c +++ b/fs/ocfs2/localalloc.c @@ -28,6 +28,7 @@ #include <linux/slab.h> #include <linux/highmem.h> #include <linux/bitops.h> +#include <linux/debugfs.h> #define MLOG_MASK_PREFIX ML_DISK_ALLOC #include <cluster/masklog.h> @@ -73,6 +74,85 @@ static int ocfs2_local_alloc_new_window(struct ocfs2_super *osb, static int ocfs2_local_alloc_slide_window(struct ocfs2_super *osb, struct inode *local_alloc_inode); +#ifdef CONFIG_OCFS2_FS_STATS + +DEFINE_MUTEX(la_debug_mutex); + +static int ocfs2_la_debug_open(struct inode *inode, struct file *file) +{ + file->private_data = inode->i_private; + return 0; +} + +#define LA_DEBUG_BUF_SZ PAGE_CACHE_SIZE +#define LA_DEBUG_VER 1 +static ssize_t ocfs2_la_debug_read(struct file *file, char __user *userbuf, + size_t count, loff_t *ppos) +{ + struct ocfs2_super *osb = file->private_data; + int written, ret; + char *buf = osb->local_alloc_debug_buf; + + mutex_lock(&la_debug_mutex); + memset(buf, 0, LA_DEBUG_BUF_SZ); + + written = snprintf(buf, LA_DEBUG_BUF_SZ, + "0x%x\t0x%llx\t%u\t%u\t0x%x\n", + LA_DEBUG_VER, + (unsigned long long)osb->la_last_gd, + osb->local_alloc_default_bits, + osb->local_alloc_bits, osb->local_alloc_state); + + ret = simple_read_from_buffer(userbuf, count, ppos, buf, written); + + mutex_unlock(&la_debug_mutex); + return ret; +} + +static const struct file_operations ocfs2_la_debug_fops = { + .open = ocfs2_la_debug_open, + .read = ocfs2_la_debug_read, +}; + +static void ocfs2_init_la_debug(struct ocfs2_super *osb) +{ + osb->local_alloc_debug_buf = kmalloc(LA_DEBUG_BUF_SZ, GFP_NOFS); + if (!osb->local_alloc_debug_buf) + return; + + osb->local_alloc_debug = debugfs_create_file("local_alloc_stats", + S_IFREG|S_IRUSR, + osb->osb_debug_root, + osb, + &ocfs2_la_debug_fops); + if (!osb->local_alloc_debug) { + kfree(osb->local_alloc_debug_buf); + osb->local_alloc_debug_buf = NULL; + } +} + +static void ocfs2_shutdown_la_debug(struct ocfs2_super *osb) +{ + if (osb->local_alloc_debug) + debugfs_remove(osb->local_alloc_debug); + + if (osb->local_alloc_debug_buf) + kfree(osb->local_alloc_debug_buf); + + osb->local_alloc_debug_buf = NULL; + osb->local_alloc_debug = NULL; +} +#else /* CONFIG_OCFS2_FS_STATS */ +static void ocfs2_init_la_debug(struct ocfs2_super *osb) +{ + return; +} +static void ocfs2_shutdown_la_debug(struct ocfs2_super *osb) +{ + return; +} +#endif + static inline int ocfs2_la_state_enabled(struct ocfs2_super *osb) { return (osb->local_alloc_state == OCFS2_LA_THROTTLED || @@ -146,6 +226,8 @@ int ocfs2_load_local_alloc(struct ocfs2_super *osb) mlog_entry_void(); + ocfs2_init_la_debug(osb); + if (osb->local_alloc_bits == 0) goto bail; @@ -218,6 +300,9 @@ bail: if (inode) iput(inode); + if (status < 0) + ocfs2_shutdown_la_debug(osb); + mlog(0, "Local alloc window bits = %d\n", osb->local_alloc_bits); mlog_exit(status); @@ -247,6 +332,8 @@ void ocfs2_shutdown_local_alloc(struct ocfs2_super *osb) cancel_delayed_work(&osb->la_enable_wq); flush_workqueue(ocfs2_wq); + ocfs2_shutdown_la_debug(osb); + if (osb->local_alloc_state == OCFS2_LA_UNUSED) goto out; |