drbd: debugfs: add basic hierarchy

Add new debugfs hierarchy /sys/kernel/debug/
  drbd/
    resources/
      $resource_name/connections/peer/$volume_number/
      $resource_name/volumes/$volume_number/
    minors/$minor_number -> ../resources/$resource_name/volumes/$volume_number/

Followup commits will populate this hierarchy with files containing
statistics, diagnostic information and some attribute data.

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
This commit is contained in:
Lars Ellenberg 2014-05-02 13:19:51 +02:00 committed by Philipp Reisner
parent 4ce4926683
commit 4d3d5aa83a
5 changed files with 278 additions and 5 deletions

View file

@ -3,5 +3,6 @@ drbd-y += drbd_worker.o drbd_receiver.o drbd_req.o drbd_actlog.o
drbd-y += drbd_main.o drbd_strings.o drbd_nl.o
drbd-y += drbd_interval.o drbd_state.o
drbd-y += drbd_nla.o
drbd-$(CONFIG_DEBUG_FS) += drbd_debugfs.o
obj-$(CONFIG_BLK_DEV_DRBD) += drbd.o

View file

@ -0,0 +1,191 @@
#define pr_fmt(fmt) "drbd debugfs: " fmt
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/debugfs.h>
#include <linux/stat.h>
#include <linux/list.h>
#include "drbd_int.h"
#include "drbd_req.h"
#include "drbd_debugfs.h"
static struct dentry *drbd_debugfs_root;
static struct dentry *drbd_debugfs_resources;
static struct dentry *drbd_debugfs_minors;
void drbd_debugfs_resource_add(struct drbd_resource *resource)
{
struct dentry *dentry;
if (!drbd_debugfs_resources)
return;
dentry = debugfs_create_dir(resource->name, drbd_debugfs_resources);
if (IS_ERR_OR_NULL(dentry))
goto fail;
resource->debugfs_res = dentry;
dentry = debugfs_create_dir("volumes", resource->debugfs_res);
if (IS_ERR_OR_NULL(dentry))
goto fail;
resource->debugfs_res_volumes = dentry;
dentry = debugfs_create_dir("connections", resource->debugfs_res);
if (IS_ERR_OR_NULL(dentry))
goto fail;
resource->debugfs_res_connections = dentry;
return;
fail:
drbd_debugfs_resource_cleanup(resource);
drbd_err(resource, "failed to create debugfs dentry\n");
}
static void drbd_debugfs_remove(struct dentry **dp)
{
debugfs_remove(*dp);
*dp = NULL;
}
void drbd_debugfs_resource_cleanup(struct drbd_resource *resource)
{
/* it is ok to call debugfs_remove(NULL) */
drbd_debugfs_remove(&resource->debugfs_res_in_flight_summary);
drbd_debugfs_remove(&resource->debugfs_res_connections);
drbd_debugfs_remove(&resource->debugfs_res_volumes);
drbd_debugfs_remove(&resource->debugfs_res);
}
void drbd_debugfs_connection_add(struct drbd_connection *connection)
{
struct dentry *conns_dir = connection->resource->debugfs_res_connections;
struct dentry *dentry;
if (!conns_dir)
return;
/* Once we enable mutliple peers,
* these connections will have descriptive names.
* For now, it is just the one connection to the (only) "peer". */
dentry = debugfs_create_dir("peer", conns_dir);
if (IS_ERR_OR_NULL(dentry))
goto fail;
connection->debugfs_conn = dentry;
return;
fail:
drbd_debugfs_connection_cleanup(connection);
drbd_err(connection, "failed to create debugfs dentry\n");
}
void drbd_debugfs_connection_cleanup(struct drbd_connection *connection)
{
drbd_debugfs_remove(&connection->debugfs_conn_callback_history);
drbd_debugfs_remove(&connection->debugfs_conn_oldest_requests);
drbd_debugfs_remove(&connection->debugfs_conn);
}
void drbd_debugfs_device_add(struct drbd_device *device)
{
struct dentry *vols_dir = device->resource->debugfs_res_volumes;
char minor_buf[8]; /* MINORMASK, MINORBITS == 20; */
char vnr_buf[8]; /* volume number vnr is even 16 bit only; */
char *slink_name = NULL;
struct dentry *dentry;
if (!vols_dir || !drbd_debugfs_minors)
return;
snprintf(vnr_buf, sizeof(vnr_buf), "%u", device->vnr);
dentry = debugfs_create_dir(vnr_buf, vols_dir);
if (IS_ERR_OR_NULL(dentry))
goto fail;
device->debugfs_vol = dentry;
snprintf(minor_buf, sizeof(minor_buf), "%u", device->minor);
slink_name = kasprintf(GFP_KERNEL, "../resources/%s/volumes/%u",
device->resource->name, device->vnr);
if (!slink_name)
goto fail;
dentry = debugfs_create_symlink(minor_buf, drbd_debugfs_minors, slink_name);
if (IS_ERR_OR_NULL(dentry))
goto fail;
device->debugfs_minor = dentry;
kfree(slink_name);
fail:
drbd_debugfs_device_cleanup(device);
drbd_err(device, "failed to create debugfs entries\n");
}
void drbd_debugfs_device_cleanup(struct drbd_device *device)
{
drbd_debugfs_remove(&device->debugfs_minor);
drbd_debugfs_remove(&device->debugfs_vol_oldest_requests);
drbd_debugfs_remove(&device->debugfs_vol_act_log_extents);
drbd_debugfs_remove(&device->debugfs_vol_resync_extents);
drbd_debugfs_remove(&device->debugfs_vol_data_gen_id);
drbd_debugfs_remove(&device->debugfs_vol);
}
void drbd_debugfs_peer_device_add(struct drbd_peer_device *peer_device)
{
struct dentry *conn_dir = peer_device->connection->debugfs_conn;
struct dentry *dentry;
char vnr_buf[8];
if (!conn_dir)
return;
snprintf(vnr_buf, sizeof(vnr_buf), "%u", peer_device->device->vnr);
dentry = debugfs_create_dir(vnr_buf, conn_dir);
if (IS_ERR_OR_NULL(dentry))
goto fail;
peer_device->debugfs_peer_dev = dentry;
return;
fail:
drbd_debugfs_peer_device_cleanup(peer_device);
drbd_err(peer_device, "failed to create debugfs entries\n");
}
void drbd_debugfs_peer_device_cleanup(struct drbd_peer_device *peer_device)
{
drbd_debugfs_remove(&peer_device->debugfs_peer_dev);
}
/* not __exit, may be indirectly called
* from the module-load-failure path as well. */
void drbd_debugfs_cleanup(void)
{
drbd_debugfs_remove(&drbd_debugfs_resources);
drbd_debugfs_remove(&drbd_debugfs_minors);
drbd_debugfs_remove(&drbd_debugfs_root);
}
int __init drbd_debugfs_init(void)
{
struct dentry *dentry;
dentry = debugfs_create_dir("drbd", NULL);
if (IS_ERR_OR_NULL(dentry))
goto fail;
drbd_debugfs_root = dentry;
dentry = debugfs_create_dir("resources", drbd_debugfs_root);
if (IS_ERR_OR_NULL(dentry))
goto fail;
drbd_debugfs_resources = dentry;
dentry = debugfs_create_dir("minors", drbd_debugfs_root);
if (IS_ERR_OR_NULL(dentry))
goto fail;
drbd_debugfs_minors = dentry;
return 0;
fail:
drbd_debugfs_cleanup();
if (dentry)
return PTR_ERR(dentry);
else
return -EINVAL;
}

View file

@ -0,0 +1,39 @@
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/debugfs.h>
#include "drbd_int.h"
#ifdef CONFIG_DEBUG_FS
int __init drbd_debugfs_init(void);
void drbd_debugfs_cleanup(void);
void drbd_debugfs_resource_add(struct drbd_resource *resource);
void drbd_debugfs_resource_cleanup(struct drbd_resource *resource);
void drbd_debugfs_connection_add(struct drbd_connection *connection);
void drbd_debugfs_connection_cleanup(struct drbd_connection *connection);
void drbd_debugfs_device_add(struct drbd_device *device);
void drbd_debugfs_device_cleanup(struct drbd_device *device);
void drbd_debugfs_peer_device_add(struct drbd_peer_device *peer_device);
void drbd_debugfs_peer_device_cleanup(struct drbd_peer_device *peer_device);
#else
static inline int __init drbd_debugfs_init(void) { return -ENODEV; }
static inline void drbd_debugfs_cleanup(void) { }
static inline void drbd_debugfs_resource_add(struct drbd_resource *resource) { }
static inline void drbd_debugfs_resource_cleanup(struct drbd_resource *resource) { }
static inline void drbd_debugfs_connection_add(struct drbd_connection *connection) { }
static inline void drbd_debugfs_connection_cleanup(struct drbd_connection *connection) { }
static inline void drbd_debugfs_device_add(struct drbd_device *device) { }
static inline void drbd_debugfs_device_cleanup(struct drbd_device *device) { }
static inline void drbd_debugfs_peer_device_add(struct drbd_peer_device *peer_device) { }
static inline void drbd_debugfs_peer_device_cleanup(struct drbd_peer_device *peer_device) { }
#endif

View file

@ -670,6 +670,12 @@ enum {
struct drbd_resource {
char *name;
#ifdef CONFIG_DEBUG_FS
struct dentry *debugfs_res;
struct dentry *debugfs_res_volumes;
struct dentry *debugfs_res_connections;
struct dentry *debugfs_res_in_flight_summary;
#endif
struct kref kref;
struct idr devices; /* volume number to device mapping */
struct list_head connections;
@ -691,6 +697,11 @@ struct drbd_resource {
struct drbd_connection {
struct list_head connections;
struct drbd_resource *resource;
#ifdef CONFIG_DEBUG_FS
struct dentry *debugfs_conn;
struct dentry *debugfs_conn_callback_history;
struct dentry *debugfs_conn_oldest_requests;
#endif
struct kref kref;
struct idr peer_devices; /* volume number to peer device mapping */
enum drbd_conns cstate; /* Only C_STANDALONE to C_WF_REPORT_PARAMS */
@ -772,13 +783,29 @@ struct drbd_peer_device {
struct list_head peer_devices;
struct drbd_device *device;
struct drbd_connection *connection;
#ifdef CONFIG_DEBUG_FS
struct dentry *debugfs_peer_dev;
#endif
};
struct drbd_device {
struct drbd_resource *resource;
struct list_head peer_devices;
struct list_head pending_bitmap_io;
int vnr; /* volume number within the connection */
unsigned long flush_jif;
#ifdef CONFIG_DEBUG_FS
struct dentry *debugfs_minor;
struct dentry *debugfs_vol;
struct dentry *debugfs_vol_oldest_requests;
struct dentry *debugfs_vol_act_log_extents;
struct dentry *debugfs_vol_resync_extents;
struct dentry *debugfs_vol_data_gen_id;
#endif
unsigned int vnr; /* volume number within the connection */
unsigned int minor; /* device minor number */
struct kref kref;
/* things that are stored as / read from meta data on disk */
@ -895,7 +922,6 @@ struct drbd_device {
atomic_t packet_seq;
unsigned int peer_seq;
spinlock_t peer_seq_lock;
unsigned int minor;
unsigned long comm_bm_set; /* communicated number of set bits. */
struct bm_io_work bm_io_work;
u64 ed_uuid; /* UUID of the exposed data */

View file

@ -57,8 +57,8 @@
#include "drbd_int.h"
#include "drbd_protocol.h"
#include "drbd_req.h" /* only for _req_mod in tl_release and tl_clear */
#include "drbd_vli.h"
#include "drbd_debugfs.h"
static DEFINE_MUTEX(drbd_main_mutex);
static int drbd_open(struct block_device *bdev, fmode_t mode);
@ -2308,8 +2308,10 @@ void drbd_free_resource(struct drbd_resource *resource)
for_each_connection_safe(connection, tmp, resource) {
list_del(&connection->connections);
drbd_debugfs_connection_cleanup(connection);
kref_put(&connection->kref, drbd_destroy_connection);
}
drbd_debugfs_resource_cleanup(resource);
kref_put(&resource->kref, drbd_destroy_resource);
}
@ -2334,6 +2336,7 @@ static void drbd_cleanup(void)
destroy_workqueue(retry.wq);
drbd_genl_unregister();
drbd_debugfs_cleanup();
idr_for_each_entry(&drbd_devices, device, i)
drbd_delete_device(device);
@ -2583,6 +2586,7 @@ struct drbd_resource *drbd_create_resource(const char *name)
mutex_init(&resource->conf_update);
mutex_init(&resource->adm_mutex);
spin_lock_init(&resource->req_lock);
drbd_debugfs_resource_add(resource);
return resource;
fail_free_name:
@ -2593,7 +2597,7 @@ struct drbd_resource *drbd_create_resource(const char *name)
return NULL;
}
/* caller must be under genl_lock() */
/* caller must be under adm_mutex */
struct drbd_connection *conn_create(const char *name, struct res_opts *res_opts)
{
struct drbd_resource *resource;
@ -2651,6 +2655,7 @@ struct drbd_connection *conn_create(const char *name, struct res_opts *res_opts)
kref_get(&resource->kref);
list_add_tail_rcu(&connection->connections, &resource->connections);
drbd_debugfs_connection_add(connection);
return connection;
fail_resource:
@ -2829,7 +2834,10 @@ enum drbd_ret_code drbd_create_device(struct drbd_config_context *adm_ctx, unsig
for_each_peer_device(peer_device, device)
drbd_connected(peer_device);
}
/* move to create_peer_device() */
for_each_peer_device(peer_device, device)
drbd_debugfs_peer_device_add(peer_device);
drbd_debugfs_device_add(device);
return NO_ERROR;
out_idr_remove_vol:
@ -2868,8 +2876,13 @@ void drbd_delete_device(struct drbd_device *device)
{
struct drbd_resource *resource = device->resource;
struct drbd_connection *connection;
struct drbd_peer_device *peer_device;
int refs = 3;
/* move to free_peer_device() */
for_each_peer_device(peer_device, device)
drbd_debugfs_peer_device_cleanup(peer_device);
drbd_debugfs_device_cleanup(device);
for_each_connection(connection, resource) {
idr_remove(&connection->peer_devices, device->vnr);
refs++;
@ -2938,6 +2951,9 @@ static int __init drbd_init(void)
spin_lock_init(&retry.lock);
INIT_LIST_HEAD(&retry.writes);
if (drbd_debugfs_init())
pr_notice("failed to initialize debugfs -- will not be available\n");
pr_info("initialized. "
"Version: " REL_VERSION " (api:%d/proto:%d-%d)\n",
API_VERSION, PRO_VERSION_MIN, PRO_VERSION_MAX);