fs: dlm: add midcomms debugfs functionality

This patch adds functionality to debug midcomms per connection state
inside a comms directory which is similar like dlm configfs. Currently
there exists the possibility to read out two attributes which is the
send queue counter and the version of each midcomms node state.

Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>

diff --git a/fs/dlm/debug_fs.c b/fs/dlm/debug_fs.c
index d5bd990bcab8bed8ef8deafef06cbf08fc13b244..47e9d57e4cae36d21dd77b21585587b3bb8f8dfc 100644 (file)
--- a/fs/dlm/debug_fs.c
+++ b/fs/dlm/debug_fs.c
@@ -16,6 +16,7 @@
 #include <linux/slab.h>
 
 #include "dlm_internal.h"
+#include "midcomms.h"
 #include "lock.h"
 
 #define DLM_DEBUG_BUF_LEN 4096
@@ -23,6 +24,7 @@ static char debug_buf[DLM_DEBUG_BUF_LEN];
 static struct mutex debug_buf_lock;
 
 static struct dentry *dlm_root;
+static struct dentry *dlm_comms;
 
 static char *print_lockmode(int mode)
 {
@@ -738,6 +740,57 @@ void dlm_delete_debug_file(struct dlm_ls *ls)
        debugfs_remove(ls->ls_debug_toss_dentry);
 }
 
+static int dlm_state_show(struct seq_file *file, void *offset)
+{
+       seq_printf(file, "%s\n", dlm_midcomms_state(file->private));
+       return 0;
+}
+DEFINE_SHOW_ATTRIBUTE(dlm_state);
+
+static int dlm_flags_show(struct seq_file *file, void *offset)
+{
+       seq_printf(file, "%lu\n", dlm_midcomms_flags(file->private));
+       return 0;
+}
+DEFINE_SHOW_ATTRIBUTE(dlm_flags);
+
+static int dlm_send_queue_cnt_show(struct seq_file *file, void *offset)
+{
+       seq_printf(file, "%d\n", dlm_midcomms_send_queue_cnt(file->private));
+       return 0;
+}
+DEFINE_SHOW_ATTRIBUTE(dlm_send_queue_cnt);
+
+static int dlm_version_show(struct seq_file *file, void *offset)
+{
+       seq_printf(file, "0x%08x\n", dlm_midcomms_version(file->private));
+       return 0;
+}
+DEFINE_SHOW_ATTRIBUTE(dlm_version);
+
+void *dlm_create_debug_comms_file(int nodeid, void *data)
+{
+       struct dentry *d_node;
+       char name[256];
+
+       memset(name, 0, sizeof(name));
+       snprintf(name, 256, "%d", nodeid);
+
+       d_node = debugfs_create_dir(name, dlm_comms);
+       debugfs_create_file("state", 0444, d_node, data, &dlm_state_fops);
+       debugfs_create_file("flags", 0444, d_node, data, &dlm_flags_fops);
+       debugfs_create_file("send_queue_count", 0444, d_node, data,
+                           &dlm_send_queue_cnt_fops);
+       debugfs_create_file("version", 0444, d_node, data, &dlm_version_fops);
+
+       return d_node;
+}
+
+void dlm_delete_debug_comms_file(void *ctx)
+{
+       debugfs_remove(ctx);
+}
+
 void dlm_create_debug_file(struct dlm_ls *ls)
 {
        char name[DLM_LOCKSPACE_LEN + 8];
@@ -797,6 +850,7 @@ void __init dlm_register_debugfs(void)
 {
        mutex_init(&debug_buf_lock);
        dlm_root = debugfs_create_dir("dlm", NULL);
+       dlm_comms = debugfs_create_dir("comms", dlm_root);
 }
 
 void dlm_unregister_debugfs(void)

diff --git a/fs/dlm/dlm_internal.h b/fs/dlm/dlm_internal.h
index 40917c878370baeb293230ee2774dba871939ea9..91d1ca3a121a42fbc5ced1767613ece1299f51d0 100644 (file)
--- a/fs/dlm/dlm_internal.h
+++ b/fs/dlm/dlm_internal.h
@@ -754,11 +754,15 @@ void dlm_register_debugfs(void);
 void dlm_unregister_debugfs(void);
 void dlm_create_debug_file(struct dlm_ls *ls);
 void dlm_delete_debug_file(struct dlm_ls *ls);
+void *dlm_create_debug_comms_file(int nodeid, void *data);
+void dlm_delete_debug_comms_file(void *ctx);
 #else
 static inline void dlm_register_debugfs(void) { }
 static inline void dlm_unregister_debugfs(void) { }
 static inline void dlm_create_debug_file(struct dlm_ls *ls) { }
 static inline void dlm_delete_debug_file(struct dlm_ls *ls) { }
+static inline void *dlm_create_debug_comms_file(int nodeid, void *data) { return NULL; }
+static inline void dlm_delete_debug_comms_file(void *ctx) { }
 #endif
 
 #endif                         /* __DLM_INTERNAL_DOT_H__ */

diff --git a/fs/dlm/midcomms.c b/fs/dlm/midcomms.c
index eef3938a363e333c629321c5c66f2c24029d7a76..35664950f6b7b7cb7198de8da7a430545412cf3b 100644 (file)
--- a/fs/dlm/midcomms.c
+++ b/fs/dlm/midcomms.c
@@ -189,6 +189,9 @@ struct midcomms_node {
         */
        int users;
 
+       /* not protected by srcu, node_hash lifetime */
+       void *debugfs;
+
        struct hlist_node hlist;
        struct rcu_head rcu;
 };
@@ -244,6 +247,26 @@ static inline const char *dlm_state_str(int state)
        }
 }
 
+const char *dlm_midcomms_state(struct midcomms_node *node)
+{
+       return dlm_state_str(node->state);
+}
+
+unsigned long dlm_midcomms_flags(struct midcomms_node *node)
+{
+       return node->flags;
+}
+
+int dlm_midcomms_send_queue_cnt(struct midcomms_node *node)
+{
+       return atomic_read(&node->send_queue_cnt);
+}
+
+uint32_t dlm_midcomms_version(struct midcomms_node *node)
+{
+       return node->version;
+}
+
 static struct midcomms_node *__find_node(int nodeid, int r)
 {
        struct midcomms_node *node;
@@ -332,6 +355,8 @@ static struct midcomms_node *nodeid2node(int nodeid, gfp_t alloc)
 
        hlist_add_head_rcu(&node->hlist, &node_hash[r]);
        spin_unlock(&nodes_lock);
+
+       node->debugfs = dlm_create_debug_comms_file(nodeid, node);
        return node;
 }
 
@@ -1285,6 +1310,8 @@ void dlm_midcomms_shutdown(void)
                hlist_for_each_entry_rcu(node, &node_hash[i], hlist) {
                        midcomms_shutdown(node);
 
+                       dlm_delete_debug_comms_file(node->debugfs);
+
                        spin_lock(&nodes_lock);
                        hlist_del_rcu(&node->hlist);
                        spin_unlock(&nodes_lock);

diff --git a/fs/dlm/midcomms.h b/fs/dlm/midcomms.h
index 1178b836315bc876d3088fbd5cc3d73186c38c00..579abc6929be28fbf36ede8bb51bf9fb7145bd5a 100644 (file)
--- a/fs/dlm/midcomms.h
+++ b/fs/dlm/midcomms.h
@@ -12,6 +12,8 @@
 #ifndef __MIDCOMMS_DOT_H__
 #define __MIDCOMMS_DOT_H__
 
+struct midcomms_node;
+
 int dlm_process_incoming_buffer(int nodeid, unsigned char *buf, int buflen);
 struct dlm_mhandle *dlm_midcomms_get_mhandle(int nodeid, int len,
                                             gfp_t allocation, char **ppc);
@@ -22,6 +24,10 @@ void dlm_midcomms_shutdown(void);
 void dlm_midcomms_add_member(int nodeid);
 void dlm_midcomms_remove_member(int nodeid);
 void dlm_midcomms_unack_msg_resend(int nodeid);
+const char *dlm_midcomms_state(struct midcomms_node *node);
+unsigned long dlm_midcomms_flags(struct midcomms_node *node);
+int dlm_midcomms_send_queue_cnt(struct midcomms_node *node);
+uint32_t dlm_midcomms_version(struct midcomms_node *node);
 
 #endif                         /* __MIDCOMMS_DOT_H__ */