ocfs2/hb: Expose the list of heartbeating nodes via debugfs
This patch creates a debugfs file, o2hb/livesnodes, which exposes the
aggregate list of heartbeating node across all heartbeat regions.
Signed-off-by: Sunil Mushran <sunil.mushran@oracle.com>
Signed-off-by: Mark Fasheh <mfasheh@suse.com>
diff --git a/fs/ocfs2/cluster/heartbeat.c b/fs/ocfs2/cluster/heartbeat.c
index 04697ba..4f85ece 100644
--- a/fs/ocfs2/cluster/heartbeat.c
+++ b/fs/ocfs2/cluster/heartbeat.c
@@ -33,6 +33,7 @@
#include <linux/random.h>
#include <linux/crc32.h>
#include <linux/time.h>
+#include <linux/debugfs.h>
#include "heartbeat.h"
#include "tcp.h"
@@ -60,6 +61,11 @@
static LIST_HEAD(o2hb_node_events);
static DECLARE_WAIT_QUEUE_HEAD(o2hb_steady_queue);
+#define O2HB_DEBUG_DIR "o2hb"
+#define O2HB_DEBUG_LIVENODES "livenodes"
+static struct dentry *o2hb_debug_dir;
+static struct dentry *o2hb_debug_livenodes;
+
static LIST_HEAD(o2hb_all_regions);
static struct o2hb_callback {
@@ -905,7 +911,77 @@
return 0;
}
-void o2hb_init(void)
+#ifdef CONFIG_DEBUG_FS
+static int o2hb_debug_open(struct inode *inode, struct file *file)
+{
+ unsigned long map[BITS_TO_LONGS(O2NM_MAX_NODES)];
+ char *buf = NULL;
+ int i = -1;
+ int out = 0;
+
+ buf = kmalloc(PAGE_SIZE, GFP_KERNEL);
+ if (!buf)
+ goto bail;
+
+ o2hb_fill_node_map(map, sizeof(map));
+
+ while ((i = find_next_bit(map, O2NM_MAX_NODES, i + 1)) < O2NM_MAX_NODES)
+ out += snprintf(buf + out, PAGE_SIZE - out, "%d ", i);
+ out += snprintf(buf + out, PAGE_SIZE - out, "\n");
+
+ i_size_write(inode, out);
+
+ file->private_data = buf;
+
+ return 0;
+bail:
+ return -ENOMEM;
+}
+
+static int o2hb_debug_release(struct inode *inode, struct file *file)
+{
+ kfree(file->private_data);
+ return 0;
+}
+
+static ssize_t o2hb_debug_read(struct file *file, char __user *buf,
+ size_t nbytes, loff_t *ppos)
+{
+ return simple_read_from_buffer(buf, nbytes, ppos, file->private_data,
+ i_size_read(file->f_mapping->host));
+}
+#else
+static int o2hb_debug_open(struct inode *inode, struct file *file)
+{
+ return 0;
+}
+static int o2hb_debug_release(struct inode *inode, struct file *file)
+{
+ return 0;
+}
+static ssize_t o2hb_debug_read(struct file *file, char __user *buf,
+ size_t nbytes, loff_t *ppos)
+{
+ return 0;
+}
+#endif /* CONFIG_DEBUG_FS */
+
+static struct file_operations o2hb_debug_fops = {
+ .open = o2hb_debug_open,
+ .release = o2hb_debug_release,
+ .read = o2hb_debug_read,
+ .llseek = generic_file_llseek,
+};
+
+void o2hb_exit(void)
+{
+ if (o2hb_debug_livenodes)
+ debugfs_remove(o2hb_debug_livenodes);
+ if (o2hb_debug_dir)
+ debugfs_remove(o2hb_debug_dir);
+}
+
+int o2hb_init(void)
{
int i;
@@ -918,6 +994,24 @@
INIT_LIST_HEAD(&o2hb_node_events);
memset(o2hb_live_node_bitmap, 0, sizeof(o2hb_live_node_bitmap));
+
+ o2hb_debug_dir = debugfs_create_dir(O2HB_DEBUG_DIR, NULL);
+ if (!o2hb_debug_dir) {
+ mlog_errno(-ENOMEM);
+ return -ENOMEM;
+ }
+
+ o2hb_debug_livenodes = debugfs_create_file(O2HB_DEBUG_LIVENODES,
+ S_IFREG|S_IRUSR,
+ o2hb_debug_dir, NULL,
+ &o2hb_debug_fops);
+ if (!o2hb_debug_livenodes) {
+ mlog_errno(-ENOMEM);
+ debugfs_remove(o2hb_debug_dir);
+ return -ENOMEM;
+ }
+
+ return 0;
}
/* if we're already in a callback then we're already serialized by the sem */