ceph: use rbtree for mds requests

The rbtree is a more appropriate data structure than a radix_tree.  It
avoids extra memory usage and simplifies the code.

It also fixes a bug where the debugfs 'mdsc' file wasn't including the
most recent mds request.

Signed-off-by: Sage Weil <sage@newdream.net>
This commit is contained in:
Sage Weil 2010-02-15 12:08:46 -08:00
parent 91e45ce389
commit 44ca18f268
3 changed files with 97 additions and 69 deletions

View file

@ -142,21 +142,16 @@ static int monc_show(struct seq_file *s, void *p)
static int mdsc_show(struct seq_file *s, void *p)
{
struct ceph_client *client = s->private;
struct ceph_mds_request *req;
u64 nexttid = 0;
int got;
struct ceph_mds_client *mdsc = &client->mdsc;
struct ceph_mds_request *req;
struct rb_node *rp;
int pathlen;
u64 pathbase;
char *path;
mutex_lock(&mdsc->mutex);
while (nexttid < mdsc->last_tid) {
got = radix_tree_gang_lookup(&mdsc->request_tree,
(void **)&req, nexttid, 1);
if (got == 0)
break;
nexttid = req->r_tid + 1;
for (rp = rb_first(&mdsc->request_tree); rp; rp = rb_next(rp)) {
req = rb_entry(rp, struct ceph_mds_request, r_node);
if (req->r_request)
seq_printf(s, "%lld\tmds%d\t", req->r_tid, req->r_mds);

View file

@ -255,6 +255,7 @@ static const char *session_state_name(int s)
case CEPH_MDS_SESSION_OPEN: return "open";
case CEPH_MDS_SESSION_HUNG: return "hung";
case CEPH_MDS_SESSION_CLOSING: return "closing";
case CEPH_MDS_SESSION_RESTARTING: return "restarting";
case CEPH_MDS_SESSION_RECONNECTING: return "reconnecting";
default: return "???";
}
@ -448,10 +449,42 @@ static struct ceph_mds_request *__lookup_request(struct ceph_mds_client *mdsc,
u64 tid)
{
struct ceph_mds_request *req;
req = radix_tree_lookup(&mdsc->request_tree, tid);
if (req)
ceph_mdsc_get_request(req);
return req;
struct rb_node *n = mdsc->request_tree.rb_node;
while (n) {
req = rb_entry(n, struct ceph_mds_request, r_node);
if (tid < req->r_tid)
n = n->rb_left;
else if (tid > req->r_tid)
n = n->rb_right;
else {
ceph_mdsc_get_request(req);
return req;
}
}
return NULL;
}
static void __insert_request(struct ceph_mds_client *mdsc,
struct ceph_mds_request *new)
{
struct rb_node **p = &mdsc->request_tree.rb_node;
struct rb_node *parent = NULL;
struct ceph_mds_request *req = NULL;
while (*p) {
parent = *p;
req = rb_entry(parent, struct ceph_mds_request, r_node);
if (new->r_tid < req->r_tid)
p = &(*p)->rb_left;
else if (new->r_tid > req->r_tid)
p = &(*p)->rb_right;
else
BUG();
}
rb_link_node(&new->r_node, parent, p);
rb_insert_color(&new->r_node, &mdsc->request_tree);
}
/*
@ -469,7 +502,7 @@ static void __register_request(struct ceph_mds_client *mdsc,
ceph_reserve_caps(&req->r_caps_reservation, req->r_num_caps);
dout("__register_request %p tid %lld\n", req, req->r_tid);
ceph_mdsc_get_request(req);
radix_tree_insert(&mdsc->request_tree, req->r_tid, (void *)req);
__insert_request(mdsc, req);
if (dir) {
struct ceph_inode_info *ci = ceph_inode(dir);
@ -485,7 +518,7 @@ static void __unregister_request(struct ceph_mds_client *mdsc,
struct ceph_mds_request *req)
{
dout("__unregister_request %p tid %lld\n", req, req->r_tid);
radix_tree_delete(&mdsc->request_tree, req->r_tid);
rb_erase(&req->r_node, &mdsc->request_tree);
ceph_mdsc_put_request(req);
if (req->r_unsafe_dir) {
@ -1115,17 +1148,25 @@ ceph_mdsc_create_request(struct ceph_mds_client *mdsc, int op, int mode)
}
/*
* return oldest (lowest) tid in request tree, 0 if none.
* return oldest (lowest) request, tid in request tree, 0 if none.
*
* called under mdsc->mutex.
*/
static struct ceph_mds_request *__get_oldest_req(struct ceph_mds_client *mdsc)
{
if (RB_EMPTY_ROOT(&mdsc->request_tree))
return NULL;
return rb_entry(rb_first(&mdsc->request_tree),
struct ceph_mds_request, r_node);
}
static u64 __get_oldest_tid(struct ceph_mds_client *mdsc)
{
struct ceph_mds_request *first;
if (radix_tree_gang_lookup(&mdsc->request_tree,
(void **)&first, 0, 1) <= 0)
return 0;
return first->r_tid;
struct ceph_mds_request *req = __get_oldest_req(mdsc);
if (req)
return req->r_tid;
return 0;
}
/*
@ -1540,26 +1581,19 @@ static void __wake_requests(struct ceph_mds_client *mdsc,
*/
static void kick_requests(struct ceph_mds_client *mdsc, int mds, int all)
{
struct ceph_mds_request *reqs[10];
u64 nexttid = 0;
int i, got;
struct ceph_mds_request *req;
struct rb_node *p;
dout("kick_requests mds%d\n", mds);
while (nexttid <= mdsc->last_tid) {
got = radix_tree_gang_lookup(&mdsc->request_tree,
(void **)&reqs, nexttid, 10);
if (got == 0)
break;
nexttid = reqs[got-1]->r_tid + 1;
for (i = 0; i < got; i++) {
if (reqs[i]->r_got_unsafe)
continue;
if (reqs[i]->r_session &&
reqs[i]->r_session->s_mds == mds) {
dout(" kicking tid %llu\n", reqs[i]->r_tid);
put_request_session(reqs[i]);
__do_request(mdsc, reqs[i]);
}
for (p = rb_first(&mdsc->request_tree); p; p = rb_next(p)) {
req = rb_entry(p, struct ceph_mds_request, r_node);
if (req->r_got_unsafe)
continue;
if (req->r_session &&
req->r_session->s_mds == mds) {
dout(" kicking tid %llu\n", req->r_tid);
put_request_session(req);
__do_request(mdsc, req);
}
}
}
@ -1748,7 +1782,7 @@ static void handle_reply(struct ceph_mds_session *session, struct ceph_msg *msg)
list_del_init(&req->r_unsafe_item);
/* last unsafe request during umount? */
if (mdsc->stopping && !__get_oldest_tid(mdsc))
if (mdsc->stopping && !__get_oldest_req(mdsc))
complete(&mdsc->safe_umount_waiters);
mutex_unlock(&mdsc->mutex);
goto out;
@ -2573,7 +2607,7 @@ int ceph_mdsc_init(struct ceph_mds_client *mdsc, struct ceph_client *client)
INIT_LIST_HEAD(&mdsc->snap_empty);
spin_lock_init(&mdsc->snap_empty_lock);
mdsc->last_tid = 0;
INIT_RADIX_TREE(&mdsc->request_tree, GFP_NOFS);
mdsc->request_tree = RB_ROOT;
INIT_DELAYED_WORK(&mdsc->delayed_work, delayed_work);
mdsc->last_renew_caps = jiffies;
INIT_LIST_HEAD(&mdsc->cap_delay_list);
@ -2600,20 +2634,19 @@ static void wait_requests(struct ceph_mds_client *mdsc)
struct ceph_client *client = mdsc->client;
mutex_lock(&mdsc->mutex);
if (__get_oldest_tid(mdsc)) {
if (__get_oldest_req(mdsc)) {
mutex_unlock(&mdsc->mutex);
dout("wait_requests waiting for requests\n");
wait_for_completion_timeout(&mdsc->safe_umount_waiters,
client->mount_args->mount_timeout * HZ);
mutex_lock(&mdsc->mutex);
/* tear down remaining requests */
while (radix_tree_gang_lookup(&mdsc->request_tree,
(void **)&req, 0, 1)) {
mutex_lock(&mdsc->mutex);
while ((req = __get_oldest_req(mdsc))) {
dout("wait_requests timed out on tid %llu\n",
req->r_tid);
radix_tree_delete(&mdsc->request_tree, req->r_tid);
ceph_mdsc_put_request(req);
__unregister_request(mdsc, req);
}
}
mutex_unlock(&mdsc->mutex);
@ -2639,31 +2672,29 @@ void ceph_mdsc_pre_umount(struct ceph_mds_client *mdsc)
*/
static void wait_unsafe_requests(struct ceph_mds_client *mdsc, u64 want_tid)
{
struct ceph_mds_request *req;
u64 next_tid = 0;
int got;
struct ceph_mds_request *req = NULL;
struct rb_node *n;
mutex_lock(&mdsc->mutex);
dout("wait_unsafe_requests want %lld\n", want_tid);
while (1) {
got = radix_tree_gang_lookup(&mdsc->request_tree, (void **)&req,
next_tid, 1);
if (!got)
req = __get_oldest_req(mdsc);
while (req && req->r_tid <= want_tid) {
if ((req->r_op & CEPH_MDS_OP_WRITE)) {
/* write op */
ceph_mdsc_get_request(req);
mutex_unlock(&mdsc->mutex);
dout("wait_unsafe_requests wait on %llu (want %llu)\n",
req->r_tid, want_tid);
wait_for_completion(&req->r_safe_completion);
mutex_lock(&mdsc->mutex);
n = rb_next(&req->r_node);
ceph_mdsc_put_request(req);
} else {
n = rb_next(&req->r_node);
}
if (!n)
break;
if (req->r_tid > want_tid)
break;
next_tid = req->r_tid + 1;
if ((req->r_op & CEPH_MDS_OP_WRITE) == 0)
continue; /* not a write op */
ceph_mdsc_get_request(req);
mutex_unlock(&mdsc->mutex);
dout("wait_unsafe_requests wait on %llu (want %llu)\n",
req->r_tid, want_tid);
wait_for_completion(&req->r_safe_completion);
mutex_lock(&mdsc->mutex);
ceph_mdsc_put_request(req);
req = rb_entry(n, struct ceph_mds_request, r_node);
}
mutex_unlock(&mdsc->mutex);
dout("wait_unsafe_requests done\n");

View file

@ -6,6 +6,7 @@
#include <linux/list.h>
#include <linux/mutex.h>
#include <linux/radix-tree.h>
#include <linux/rbtree.h>
#include <linux/spinlock.h>
#include "types.h"
@ -150,6 +151,7 @@ typedef void (*ceph_mds_request_callback_t) (struct ceph_mds_client *mdsc,
*/
struct ceph_mds_request {
u64 r_tid; /* transaction id */
struct rb_node r_node;
int r_op; /* mds op code */
int r_mds;
@ -249,7 +251,7 @@ struct ceph_mds_client {
spinlock_t snap_empty_lock; /* protect snap_empty */
u64 last_tid; /* most recent mds request */
struct radix_tree_root request_tree; /* pending mds requests */
struct rb_root request_tree; /* pending mds requests */
struct delayed_work delayed_work; /* delayed work */
unsigned long last_renew_caps; /* last time we renewed our caps */
struct list_head cap_delay_list; /* caps with delayed release */