#include <linux/gfs2_ondisk.h>
#include <linux/list.h>
#include <linux/lm_interface.h>
+#include <linux/wait.h>
+#include <linux/module.h>
+#include <linux/rwsem.h>
#include <asm/uaccess.h>
+#include <linux/seq_file.h>
+#include <linux/debugfs.h>
+#include <linux/module.h>
+#include <linux/kallsyms.h>
#include "gfs2.h"
#include "incore.h"
#include "super.h"
#include "util.h"
-struct greedy {
- struct gfs2_holder gr_gh;
- struct delayed_work gr_work;
-};
-
struct gfs2_gl_hash_bucket {
struct hlist_head hb_list;
};
+struct glock_iter {
+ int hash; /* hash bucket index */
+ struct gfs2_sbd *sdp; /* incore superblock */
+ struct gfs2_glock *gl; /* current glock struct */
+ struct hlist_head *hb_list; /* current hash bucket ptr */
+ struct seq_file *seq; /* sequence file for debugfs */
+ char string[512]; /* scratch space */
+};
+
typedef void (*glock_examiner) (struct gfs2_glock * gl);
static int gfs2_dump_lockstate(struct gfs2_sbd *sdp);
-static int dump_glock(struct gfs2_glock *gl);
-static int dump_inode(struct gfs2_inode *ip);
+static int dump_glock(struct glock_iter *gi, struct gfs2_glock *gl);
+static void gfs2_glock_xmote_th(struct gfs2_glock *gl, struct gfs2_holder *gh);
+static void gfs2_glock_drop_th(struct gfs2_glock *gl);
+static DECLARE_RWSEM(gfs2_umount_flush_sem);
+static struct dentry *gfs2_root;
#define GFS2_GL_HASH_SHIFT 15
#define GFS2_GL_HASH_SIZE (1 << GFS2_GL_HASH_SHIFT)
#define GFS2_GL_HASH_MASK (GFS2_GL_HASH_SIZE - 1)
static struct gfs2_gl_hash_bucket gl_hash_table[GFS2_GL_HASH_SIZE];
+static struct dentry *gfs2_root;
/*
* Despite what you might think, the numbers below are not arbitrary :-)
gfs2_assert(sdp, list_empty(&gl->gl_reclaim));
gfs2_assert(sdp, list_empty(&gl->gl_holders));
gfs2_assert(sdp, list_empty(&gl->gl_waiters1));
- gfs2_assert(sdp, list_empty(&gl->gl_waiters2));
gfs2_assert(sdp, list_empty(&gl->gl_waiters3));
glock_free(gl);
rv = 1;
return rv;
}
-/**
- * queue_empty - check to see if a glock's queue is empty
- * @gl: the glock
- * @head: the head of the queue to check
- *
- * This function protects the list in the event that a process already
- * has a holder on the list and is adding a second holder for itself.
- * The glmutex lock is what generally prevents processes from working
- * on the same glock at once, but the special case of adding a second
- * holder for yourself ("recursive" locking) doesn't involve locking
- * glmutex, making the spin lock necessary.
- *
- * Returns: 1 if the queue is empty
- */
-
-static inline int queue_empty(struct gfs2_glock *gl, struct list_head *head)
-{
- int empty;
- spin_lock(&gl->gl_spin);
- empty = list_empty(head);
- spin_unlock(&gl->gl_spin);
- return empty;
-}
-
/**
* search_bucket() - Find struct gfs2_glock by lock number
* @bucket: the bucket to search
atomic_set(&gl->gl_ref, 1);
gl->gl_state = LM_ST_UNLOCKED;
gl->gl_hash = hash;
- gl->gl_owner = NULL;
+ gl->gl_owner_pid = 0;
gl->gl_ip = 0;
gl->gl_ops = glops;
gl->gl_req_gh = NULL;
INIT_LIST_HEAD(&gh->gh_list);
gh->gh_gl = gl;
gh->gh_ip = (unsigned long)__builtin_return_address(0);
- gh->gh_owner = current;
+ gh->gh_owner_pid = current->pid;
gh->gh_state = state;
gh->gh_flags = flags;
gh->gh_error = 0;
gh->gh_iflags = 0;
- init_completion(&gh->gh_wait);
-
- if (gh->gh_state == LM_ST_EXCLUSIVE)
- gh->gh_flags |= GL_LOCAL_EXCL;
-
gfs2_glock_hold(gl);
}
{
gh->gh_state = state;
gh->gh_flags = flags;
- if (gh->gh_state == LM_ST_EXCLUSIVE)
- gh->gh_flags |= GL_LOCAL_EXCL;
-
- gh->gh_iflags &= 1 << HIF_ALLOCED;
+ gh->gh_iflags = 0;
gh->gh_ip = (unsigned long)__builtin_return_address(0);
}
gh->gh_ip = 0;
}
-/**
- * gfs2_holder_get - get a struct gfs2_holder structure
- * @gl: the glock
- * @state: the state we're requesting
- * @flags: the modifier flags
- * @gfp_flags:
- *
- * Figure out how big an impact this function has. Either:
- * 1) Replace it with a cache of structures hanging off the struct gfs2_sbd
- * 2) Leave it like it is
- *
- * Returns: the holder structure, NULL on ENOMEM
- */
-
-static struct gfs2_holder *gfs2_holder_get(struct gfs2_glock *gl,
- unsigned int state,
- int flags, gfp_t gfp_flags)
+static void gfs2_holder_wake(struct gfs2_holder *gh)
{
- struct gfs2_holder *gh;
-
- gh = kmalloc(sizeof(struct gfs2_holder), gfp_flags);
- if (!gh)
- return NULL;
-
- gfs2_holder_init(gl, state, flags, gh);
- set_bit(HIF_ALLOCED, &gh->gh_iflags);
- gh->gh_ip = (unsigned long)__builtin_return_address(0);
- return gh;
+ clear_bit(HIF_WAIT, &gh->gh_iflags);
+ smp_mb();
+ wake_up_bit(&gh->gh_iflags, HIF_WAIT);
}
-/**
- * gfs2_holder_put - get rid of a struct gfs2_holder structure
- * @gh: the holder structure
- *
- */
+static int holder_wait(void *word)
+{
+ schedule();
+ return 0;
+}
-static void gfs2_holder_put(struct gfs2_holder *gh)
+static void wait_on_holder(struct gfs2_holder *gh)
{
- gfs2_holder_uninit(gh);
- kfree(gh);
+ might_sleep();
+ wait_on_bit(&gh->gh_iflags, HIF_WAIT, holder_wait, TASK_UNINTERRUPTIBLE);
}
/**
list_del_init(&gh->gh_list);
/* gh->gh_error never examined. */
set_bit(GLF_LOCK, &gl->gl_flags);
- complete(&gh->gh_wait);
+ clear_bit(HIF_WAIT, &gh->gh_iflags);
+ smp_mb();
+ wake_up_bit(&gh->gh_iflags, HIF_WAIT);
return 1;
}
{
struct gfs2_glock *gl = gh->gh_gl;
struct gfs2_sbd *sdp = gl->gl_sbd;
- const struct gfs2_glock_operations *glops = gl->gl_ops;
if (!relaxed_state_ok(gl->gl_state, gh->gh_state, gh->gh_flags)) {
if (list_empty(&gl->gl_holders)) {
gfs2_reclaim_glock(sdp);
}
- glops->go_xmote_th(gl, gh->gh_state, gh->gh_flags);
+ gfs2_glock_xmote_th(gh->gh_gl, gh);
spin_lock(&gl->gl_spin);
}
return 1;
set_bit(GLF_LOCK, &gl->gl_flags);
} else {
struct gfs2_holder *next_gh;
- if (gh->gh_flags & GL_LOCAL_EXCL)
+ if (gh->gh_state == LM_ST_EXCLUSIVE)
return 1;
next_gh = list_entry(gl->gl_holders.next, struct gfs2_holder,
gh_list);
- if (next_gh->gh_flags & GL_LOCAL_EXCL)
+ if (next_gh->gh_state == LM_ST_EXCLUSIVE)
return 1;
}
gh->gh_error = 0;
set_bit(HIF_HOLDER, &gh->gh_iflags);
- complete(&gh->gh_wait);
+ gfs2_holder_wake(gh);
return 0;
}
* Returns: 1 if the queue is blocked
*/
-static int rq_demote(struct gfs2_holder *gh)
+static int rq_demote(struct gfs2_glock *gl)
{
- struct gfs2_glock *gl = gh->gh_gl;
- const struct gfs2_glock_operations *glops = gl->gl_ops;
-
if (!list_empty(&gl->gl_holders))
return 1;
- if (gl->gl_state == gh->gh_state || gl->gl_state == LM_ST_UNLOCKED) {
- list_del_init(&gh->gh_list);
- gh->gh_error = 0;
- spin_unlock(&gl->gl_spin);
- if (test_bit(HIF_DEALLOC, &gh->gh_iflags))
- gfs2_holder_put(gh);
- else
- complete(&gh->gh_wait);
- spin_lock(&gl->gl_spin);
- } else {
- gl->gl_req_gh = gh;
- set_bit(GLF_LOCK, &gl->gl_flags);
- spin_unlock(&gl->gl_spin);
-
- if (gh->gh_state == LM_ST_UNLOCKED ||
- gl->gl_state != LM_ST_EXCLUSIVE)
- glops->go_drop_th(gl);
- else
- glops->go_xmote_th(gl, gh->gh_state, gh->gh_flags);
-
- spin_lock(&gl->gl_spin);
+ if (gl->gl_state == gl->gl_demote_state ||
+ gl->gl_state == LM_ST_UNLOCKED) {
+ clear_bit(GLF_DEMOTE, &gl->gl_flags);
+ return 0;
}
-
- return 0;
-}
-
-/**
- * rq_greedy - process a queued request to drop greedy status
- * @gh: the glock holder
- *
- * Returns: 1 if the queue is blocked
- */
-
-static int rq_greedy(struct gfs2_holder *gh)
-{
- struct gfs2_glock *gl = gh->gh_gl;
-
- list_del_init(&gh->gh_list);
- /* gh->gh_error never examined. */
- clear_bit(GLF_GREEDY, &gl->gl_flags);
+ set_bit(GLF_LOCK, &gl->gl_flags);
spin_unlock(&gl->gl_spin);
-
- gfs2_holder_uninit(gh);
- kfree(container_of(gh, struct greedy, gr_gh));
-
+ if (gl->gl_demote_state == LM_ST_UNLOCKED ||
+ gl->gl_state != LM_ST_EXCLUSIVE)
+ gfs2_glock_drop_th(gl);
+ else
+ gfs2_glock_xmote_th(gl, NULL);
spin_lock(&gl->gl_spin);
return 0;
else
gfs2_assert_warn(gl->gl_sbd, 0);
- } else if (!list_empty(&gl->gl_waiters2) &&
- !test_bit(GLF_SKIP_WAITERS2, &gl->gl_flags)) {
- gh = list_entry(gl->gl_waiters2.next,
- struct gfs2_holder, gh_list);
-
- if (test_bit(HIF_DEMOTE, &gh->gh_iflags))
- blocked = rq_demote(gh);
- else if (test_bit(HIF_GREEDY, &gh->gh_iflags))
- blocked = rq_greedy(gh);
- else
- gfs2_assert_warn(gl->gl_sbd, 0);
-
+ } else if (test_bit(GLF_DEMOTE, &gl->gl_flags)) {
+ blocked = rq_demote(gl);
} else if (!list_empty(&gl->gl_waiters3)) {
gh = list_entry(gl->gl_waiters3.next,
struct gfs2_holder, gh_list);
gfs2_holder_init(gl, 0, 0, &gh);
set_bit(HIF_MUTEX, &gh.gh_iflags);
+ if (test_and_set_bit(HIF_WAIT, &gh.gh_iflags))
+ BUG();
spin_lock(&gl->gl_spin);
if (test_and_set_bit(GLF_LOCK, &gl->gl_flags)) {
list_add_tail(&gh.gh_list, &gl->gl_waiters1);
} else {
- gl->gl_owner = current;
+ gl->gl_owner_pid = current->pid;
gl->gl_ip = (unsigned long)__builtin_return_address(0);
- complete(&gh.gh_wait);
+ clear_bit(HIF_WAIT, &gh.gh_iflags);
+ smp_mb();
+ wake_up_bit(&gh.gh_iflags, HIF_WAIT);
}
spin_unlock(&gl->gl_spin);
- wait_for_completion(&gh.gh_wait);
+ wait_on_holder(&gh);
gfs2_holder_uninit(&gh);
}
if (test_and_set_bit(GLF_LOCK, &gl->gl_flags)) {
acquired = 0;
} else {
- gl->gl_owner = current;
+ gl->gl_owner_pid = current->pid;
gl->gl_ip = (unsigned long)__builtin_return_address(0);
}
spin_unlock(&gl->gl_spin);
{
spin_lock(&gl->gl_spin);
clear_bit(GLF_LOCK, &gl->gl_flags);
- gl->gl_owner = NULL;
+ gl->gl_owner_pid = 0;
gl->gl_ip = 0;
run_queue(gl);
BUG_ON(!spin_is_locked(&gl->gl_spin));
}
/**
- * handle_callback - add a demote request to a lock's queue
+ * handle_callback - process a demote request
* @gl: the glock
* @state: the state the caller wants us to change to
*
- * Note: This may fail sliently if we are out of memory.
+ * There are only two requests that we are going to see in actual
+ * practise: LM_ST_SHARED and LM_ST_UNLOCKED
*/
static void handle_callback(struct gfs2_glock *gl, unsigned int state)
{
- struct gfs2_holder *gh, *new_gh = NULL;
-
-restart:
spin_lock(&gl->gl_spin);
-
- list_for_each_entry(gh, &gl->gl_waiters2, gh_list) {
- if (test_bit(HIF_DEMOTE, &gh->gh_iflags) &&
- gl->gl_req_gh != gh) {
- if (gh->gh_state != state)
- gh->gh_state = LM_ST_UNLOCKED;
- goto out;
- }
+ if (test_and_set_bit(GLF_DEMOTE, &gl->gl_flags) == 0) {
+ gl->gl_demote_state = state;
+ gl->gl_demote_time = jiffies;
+ } else if (gl->gl_demote_state != LM_ST_UNLOCKED) {
+ gl->gl_demote_state = state;
}
-
- if (new_gh) {
- list_add_tail(&new_gh->gh_list, &gl->gl_waiters2);
- new_gh = NULL;
- } else {
- spin_unlock(&gl->gl_spin);
-
- new_gh = gfs2_holder_get(gl, state, LM_FLAG_TRY, GFP_NOFS);
- if (!new_gh)
- return;
- set_bit(HIF_DEMOTE, &new_gh->gh_iflags);
- set_bit(HIF_DEALLOC, &new_gh->gh_iflags);
-
- goto restart;
- }
-
-out:
spin_unlock(&gl->gl_spin);
-
- if (new_gh)
- gfs2_holder_put(new_gh);
}
/**
int op_done = 1;
gfs2_assert_warn(sdp, test_bit(GLF_LOCK, &gl->gl_flags));
- gfs2_assert_warn(sdp, queue_empty(gl, &gl->gl_holders));
+ gfs2_assert_warn(sdp, list_empty(&gl->gl_holders));
gfs2_assert_warn(sdp, !(ret & LM_OUT_ASYNC));
state_change(gl, ret & LM_OUT_ST_MASK);
/* Deal with each possible exit condition */
- if (!gh)
+ if (!gh) {
gl->gl_stamp = jiffies;
- else if (unlikely(test_bit(SDF_SHUTDOWN, &sdp->sd_flags))) {
+ if (ret & LM_OUT_CANCELED)
+ op_done = 0;
+ else
+ clear_bit(GLF_DEMOTE, &gl->gl_flags);
+ } else {
spin_lock(&gl->gl_spin);
list_del_init(&gh->gh_list);
gh->gh_error = -EIO;
- spin_unlock(&gl->gl_spin);
- } else if (test_bit(HIF_DEMOTE, &gh->gh_iflags)) {
- spin_lock(&gl->gl_spin);
- list_del_init(&gh->gh_list);
- if (gl->gl_state == gh->gh_state ||
- gl->gl_state == LM_ST_UNLOCKED) {
+ if (unlikely(test_bit(SDF_SHUTDOWN, &sdp->sd_flags)))
+ goto out;
+ gh->gh_error = GLR_CANCELED;
+ if (ret & LM_OUT_CANCELED)
+ goto out;
+ if (relaxed_state_ok(gl->gl_state, gh->gh_state, gh->gh_flags)) {
+ list_add_tail(&gh->gh_list, &gl->gl_holders);
gh->gh_error = 0;
- } else {
- if (gfs2_assert_warn(sdp, gh->gh_flags &
- (LM_FLAG_TRY | LM_FLAG_TRY_1CB)) == -1)
- fs_warn(sdp, "ret = 0x%.8X\n", ret);
- gh->gh_error = GLR_TRYFAILED;
+ set_bit(HIF_HOLDER, &gh->gh_iflags);
+ set_bit(HIF_FIRST, &gh->gh_iflags);
+ op_done = 0;
+ goto out;
}
- spin_unlock(&gl->gl_spin);
-
- if (ret & LM_OUT_CANCELED)
- handle_callback(gl, LM_ST_UNLOCKED);
-
- } else if (ret & LM_OUT_CANCELED) {
- spin_lock(&gl->gl_spin);
- list_del_init(&gh->gh_list);
- gh->gh_error = GLR_CANCELED;
- spin_unlock(&gl->gl_spin);
-
- } else if (relaxed_state_ok(gl->gl_state, gh->gh_state, gh->gh_flags)) {
- spin_lock(&gl->gl_spin);
- list_move_tail(&gh->gh_list, &gl->gl_holders);
- gh->gh_error = 0;
- set_bit(HIF_HOLDER, &gh->gh_iflags);
- spin_unlock(&gl->gl_spin);
-
- set_bit(HIF_FIRST, &gh->gh_iflags);
-
- op_done = 0;
-
- } else if (gh->gh_flags & (LM_FLAG_TRY | LM_FLAG_TRY_1CB)) {
- spin_lock(&gl->gl_spin);
- list_del_init(&gh->gh_list);
gh->gh_error = GLR_TRYFAILED;
- spin_unlock(&gl->gl_spin);
-
- } else {
+ if (gh->gh_flags & (LM_FLAG_TRY | LM_FLAG_TRY_1CB))
+ goto out;
+ gh->gh_error = -EINVAL;
if (gfs2_assert_withdraw(sdp, 0) == -1)
fs_err(sdp, "ret = 0x%.8X\n", ret);
+out:
+ spin_unlock(&gl->gl_spin);
}
if (glops->go_xmote_bh)
gfs2_glock_put(gl);
- if (gh) {
- if (test_bit(HIF_DEALLOC, &gh->gh_iflags))
- gfs2_holder_put(gh);
- else
- complete(&gh->gh_wait);
- }
+ if (gh)
+ gfs2_holder_wake(gh);
}
/**
*
*/
-void gfs2_glock_xmote_th(struct gfs2_glock *gl, unsigned int state, int flags)
+void gfs2_glock_xmote_th(struct gfs2_glock *gl, struct gfs2_holder *gh)
{
struct gfs2_sbd *sdp = gl->gl_sbd;
+ int flags = gh ? gh->gh_flags : 0;
+ unsigned state = gh ? gh->gh_state : gl->gl_demote_state;
const struct gfs2_glock_operations *glops = gl->gl_ops;
int lck_flags = flags & (LM_FLAG_TRY | LM_FLAG_TRY_1CB |
LM_FLAG_NOEXP | LM_FLAG_ANY |
LM_FLAG_PRIORITY);
unsigned int lck_ret;
+ if (glops->go_xmote_th)
+ glops->go_xmote_th(gl);
+
gfs2_assert_warn(sdp, test_bit(GLF_LOCK, &gl->gl_flags));
- gfs2_assert_warn(sdp, queue_empty(gl, &gl->gl_holders));
+ gfs2_assert_warn(sdp, list_empty(&gl->gl_holders));
gfs2_assert_warn(sdp, state != LM_ST_UNLOCKED);
gfs2_assert_warn(sdp, state != gl->gl_state);
- if (gl->gl_state == LM_ST_EXCLUSIVE && glops->go_sync)
- glops->go_sync(gl);
-
gfs2_glock_hold(gl);
gl->gl_req_bh = xmote_bh;
const struct gfs2_glock_operations *glops = gl->gl_ops;
struct gfs2_holder *gh = gl->gl_req_gh;
- clear_bit(GLF_PREFETCH, &gl->gl_flags);
-
gfs2_assert_warn(sdp, test_bit(GLF_LOCK, &gl->gl_flags));
- gfs2_assert_warn(sdp, queue_empty(gl, &gl->gl_holders));
+ gfs2_assert_warn(sdp, list_empty(&gl->gl_holders));
gfs2_assert_warn(sdp, !ret);
state_change(gl, LM_ST_UNLOCKED);
+ clear_bit(GLF_DEMOTE, &gl->gl_flags);
if (glops->go_inval)
glops->go_inval(gl, DIO_METADATA);
spin_unlock(&gl->gl_spin);
}
- if (glops->go_drop_bh)
- glops->go_drop_bh(gl);
-
spin_lock(&gl->gl_spin);
gl->gl_req_gh = NULL;
gl->gl_req_bh = NULL;
gfs2_glock_put(gl);
- if (gh) {
- if (test_bit(HIF_DEALLOC, &gh->gh_iflags))
- gfs2_holder_put(gh);
- else
- complete(&gh->gh_wait);
- }
+ if (gh)
+ gfs2_holder_wake(gh);
}
/**
*
*/
-void gfs2_glock_drop_th(struct gfs2_glock *gl)
+static void gfs2_glock_drop_th(struct gfs2_glock *gl)
{
struct gfs2_sbd *sdp = gl->gl_sbd;
const struct gfs2_glock_operations *glops = gl->gl_ops;
unsigned int ret;
+ if (glops->go_drop_th)
+ glops->go_drop_th(gl);
+
gfs2_assert_warn(sdp, test_bit(GLF_LOCK, &gl->gl_flags));
- gfs2_assert_warn(sdp, queue_empty(gl, &gl->gl_holders));
+ gfs2_assert_warn(sdp, list_empty(&gl->gl_holders));
gfs2_assert_warn(sdp, gl->gl_state != LM_ST_UNLOCKED);
- if (gl->gl_state == LM_ST_EXCLUSIVE && glops->go_sync)
- glops->go_sync(gl);
-
gfs2_glock_hold(gl);
gl->gl_req_bh = drop_bh;
if (gh->gh_flags & LM_FLAG_PRIORITY)
do_cancels(gh);
- wait_for_completion(&gh->gh_wait);
-
+ wait_on_holder(gh);
if (gh->gh_error)
return gh->gh_error;
}
static inline struct gfs2_holder *
-find_holder_by_owner(struct list_head *head, struct task_struct *owner)
+find_holder_by_owner(struct list_head *head, pid_t pid)
{
struct gfs2_holder *gh;
list_for_each_entry(gh, head, gh_list) {
- if (gh->gh_owner == owner)
+ if (gh->gh_owner_pid == pid)
return gh;
}
return NULL;
}
+static void print_dbg(struct glock_iter *gi, const char *fmt, ...)
+{
+ va_list args;
+
+ va_start(args, fmt);
+ if (gi) {
+ vsprintf(gi->string, fmt, args);
+ seq_printf(gi->seq, gi->string);
+ }
+ else
+ vprintk(fmt, args);
+ va_end(args);
+}
+
/**
* add_to_queue - Add a holder to the wait queue (but look for recursion)
* @gh: the holder structure to add
struct gfs2_glock *gl = gh->gh_gl;
struct gfs2_holder *existing;
- BUG_ON(!gh->gh_owner);
+ BUG_ON(!gh->gh_owner_pid);
+ if (test_and_set_bit(HIF_WAIT, &gh->gh_iflags))
+ BUG();
- existing = find_holder_by_owner(&gl->gl_holders, gh->gh_owner);
+ existing = find_holder_by_owner(&gl->gl_holders, gh->gh_owner_pid);
if (existing) {
print_symbol(KERN_WARNING "original: %s\n", existing->gh_ip);
- printk(KERN_INFO "pid : %d\n", existing->gh_owner->pid);
+ printk(KERN_INFO "pid : %d\n", existing->gh_owner_pid);
printk(KERN_INFO "lock type : %d lock state : %d\n",
existing->gh_gl->gl_name.ln_type, existing->gh_gl->gl_state);
print_symbol(KERN_WARNING "new: %s\n", gh->gh_ip);
- printk(KERN_INFO "pid : %d\n", gh->gh_owner->pid);
+ printk(KERN_INFO "pid : %d\n", gh->gh_owner_pid);
printk(KERN_INFO "lock type : %d lock state : %d\n",
gl->gl_name.ln_type, gl->gl_state);
BUG();
}
- existing = find_holder_by_owner(&gl->gl_waiters3, gh->gh_owner);
+ existing = find_holder_by_owner(&gl->gl_waiters3, gh->gh_owner_pid);
if (existing) {
print_symbol(KERN_WARNING "original: %s\n", existing->gh_ip);
print_symbol(KERN_WARNING "new: %s\n", gh->gh_ip);
}
}
- clear_bit(GLF_PREFETCH, &gl->gl_flags);
-
return error;
}
if (glops->go_unlock)
glops->go_unlock(gh);
- gl->gl_stamp = jiffies;
-
spin_lock(&gl->gl_spin);
+ gl->gl_stamp = jiffies;
}
clear_bit(GLF_LOCK, &gl->gl_flags);
spin_unlock(&gl->gl_spin);
}
-/**
- * gfs2_glock_prefetch - Try to prefetch a glock
- * @gl: the glock
- * @state: the state to prefetch in
- * @flags: flags passed to go_xmote_th()
- *
- */
-
-static void gfs2_glock_prefetch(struct gfs2_glock *gl, unsigned int state,
- int flags)
-{
- const struct gfs2_glock_operations *glops = gl->gl_ops;
-
- spin_lock(&gl->gl_spin);
-
- if (test_bit(GLF_LOCK, &gl->gl_flags) || !list_empty(&gl->gl_holders) ||
- !list_empty(&gl->gl_waiters1) || !list_empty(&gl->gl_waiters2) ||
- !list_empty(&gl->gl_waiters3) ||
- relaxed_state_ok(gl->gl_state, state, flags)) {
- spin_unlock(&gl->gl_spin);
- return;
- }
-
- set_bit(GLF_PREFETCH, &gl->gl_flags);
- set_bit(GLF_LOCK, &gl->gl_flags);
- spin_unlock(&gl->gl_spin);
-
- glops->go_xmote_th(gl, state, flags);
-}
-
-static void greedy_work(struct work_struct *work)
-{
- struct greedy *gr = container_of(work, struct greedy, gr_work.work);
- struct gfs2_holder *gh = &gr->gr_gh;
- struct gfs2_glock *gl = gh->gh_gl;
- const struct gfs2_glock_operations *glops = gl->gl_ops;
-
- clear_bit(GLF_SKIP_WAITERS2, &gl->gl_flags);
-
- if (glops->go_greedy)
- glops->go_greedy(gl);
-
- spin_lock(&gl->gl_spin);
-
- if (list_empty(&gl->gl_waiters2)) {
- clear_bit(GLF_GREEDY, &gl->gl_flags);
- spin_unlock(&gl->gl_spin);
- gfs2_holder_uninit(gh);
- kfree(gr);
- } else {
- gfs2_glock_hold(gl);
- list_add_tail(&gh->gh_list, &gl->gl_waiters2);
- run_queue(gl);
- spin_unlock(&gl->gl_spin);
- gfs2_glock_put(gl);
- }
-}
-
-/**
- * gfs2_glock_be_greedy -
- * @gl:
- * @time:
- *
- * Returns: 0 if go_greedy will be called, 1 otherwise
- */
-
-int gfs2_glock_be_greedy(struct gfs2_glock *gl, unsigned int time)
-{
- struct greedy *gr;
- struct gfs2_holder *gh;
-
- if (!time || gl->gl_sbd->sd_args.ar_localcaching ||
- test_and_set_bit(GLF_GREEDY, &gl->gl_flags))
- return 1;
-
- gr = kmalloc(sizeof(struct greedy), GFP_KERNEL);
- if (!gr) {
- clear_bit(GLF_GREEDY, &gl->gl_flags);
- return 1;
- }
- gh = &gr->gr_gh;
-
- gfs2_holder_init(gl, 0, 0, gh);
- set_bit(HIF_GREEDY, &gh->gh_iflags);
- INIT_DELAYED_WORK(&gr->gr_work, greedy_work);
-
- set_bit(GLF_SKIP_WAITERS2, &gl->gl_flags);
- schedule_delayed_work(&gr->gr_work, time);
-
- return 0;
-}
-
/**
* gfs2_glock_dq_uninit - dequeue a holder from a glock and initialize it
* @gh: the holder structure
return 1;
if (a->ln_number < b->ln_number)
return -1;
- if (gh_a->gh_state == LM_ST_SHARED && gh_b->gh_state == LM_ST_EXCLUSIVE)
- return 1;
- if (!(gh_a->gh_flags & GL_LOCAL_EXCL) && (gh_b->gh_flags & GL_LOCAL_EXCL))
- return 1;
+ BUG_ON(gh_a->gh_gl->gl_ops->go_type == gh_b->gh_gl->gl_ops->go_type);
return 0;
}
gfs2_glock_dq_uninit(&ghs[x]);
}
-/**
- * gfs2_glock_prefetch_num - prefetch a glock based on lock number
- * @sdp: the filesystem
- * @number: the lock number
- * @glops: the glock operations for the type of glock
- * @state: the state to acquire the glock in
- * @flags: modifier flags for the aquisition
- *
- * Returns: errno
- */
-
-void gfs2_glock_prefetch_num(struct gfs2_sbd *sdp, u64 number,
- const struct gfs2_glock_operations *glops,
- unsigned int state, int flags)
-{
- struct gfs2_glock *gl;
- int error;
-
- if (atomic_read(&sdp->sd_reclaim_count) <
- gfs2_tune_get(sdp, gt_reclaim_limit)) {
- error = gfs2_glock_get(sdp, number, glops, CREATE, &gl);
- if (!error) {
- gfs2_glock_prefetch(gl, state, flags);
- gfs2_glock_put(gl);
- }
- }
-}
-
/**
* gfs2_lvb_hold - attach a LVB from a glock
* @gl: The glock in question
if (!gl)
return;
- if (gl->gl_ops->go_callback)
- gl->gl_ops->go_callback(gl, state);
handle_callback(gl, state);
spin_lock(&gl->gl_spin);
struct lm_async_cb *async = data;
struct gfs2_glock *gl;
+ down_read(&gfs2_umount_flush_sem);
gl = gfs2_glock_find(sdp, &async->lc_name);
if (gfs2_assert_warn(sdp, gl))
return;
if (!gfs2_assert_warn(sdp, gl->gl_req_bh))
gl->gl_req_bh(gl, async->lc_ret);
gfs2_glock_put(gl);
+ up_read(&gfs2_umount_flush_sem);
return;
}
static int demote_ok(struct gfs2_glock *gl)
{
- struct gfs2_sbd *sdp = gl->gl_sbd;
const struct gfs2_glock_operations *glops = gl->gl_ops;
int demote = 1;
if (test_bit(GLF_STICKY, &gl->gl_flags))
demote = 0;
- else if (test_bit(GLF_PREFETCH, &gl->gl_flags))
- demote = time_after_eq(jiffies, gl->gl_stamp +
- gfs2_tune_get(sdp, gt_prefetch_secs) * HZ);
else if (glops->go_demote_ok)
demote = glops->go_demote_ok(gl);
atomic_inc(&sdp->sd_reclaimed);
if (gfs2_glmutex_trylock(gl)) {
- if (queue_empty(gl, &gl->gl_holders) &&
+ if (list_empty(&gl->gl_holders) &&
gl->gl_state != LM_ST_UNLOCKED && demote_ok(gl))
handle_callback(gl, LM_ST_UNLOCKED);
gfs2_glmutex_unlock(gl);
return;
if (gfs2_glmutex_trylock(gl)) {
- if (queue_empty(gl, &gl->gl_holders) &&
+ if (list_empty(&gl->gl_holders) &&
gl->gl_state != LM_ST_UNLOCKED && demote_ok(gl))
goto out_schedule;
gfs2_glmutex_unlock(gl);
}
if (gfs2_glmutex_trylock(gl)) {
- if (queue_empty(gl, &gl->gl_holders) &&
+ if (list_empty(&gl->gl_holders) &&
gl->gl_state != LM_ST_UNLOCKED)
handle_callback(gl, LM_ST_UNLOCKED);
gfs2_glmutex_unlock(gl);
t = jiffies;
}
+ down_write(&gfs2_umount_flush_sem);
invalidate_inodes(sdp->sd_vfs);
+ up_write(&gfs2_umount_flush_sem);
msleep(10);
}
}
* Diagnostic routines to help debug distributed deadlock
*/
+static void gfs2_print_symbol(struct glock_iter *gi, const char *fmt,
+ unsigned long address)
+{
+ char buffer[KSYM_SYMBOL_LEN];
+
+ sprint_symbol(buffer, address);
+ print_dbg(gi, fmt, buffer);
+}
+
/**
* dump_holder - print information about a glock holder
* @str: a string naming the type of holder
* Returns: 0 on success, -ENOBUFS when we run out of space
*/
-static int dump_holder(char *str, struct gfs2_holder *gh)
+static int dump_holder(struct glock_iter *gi, char *str,
+ struct gfs2_holder *gh)
{
unsigned int x;
- int error = -ENOBUFS;
-
- printk(KERN_INFO " %s\n", str);
- printk(KERN_INFO " owner = %ld\n",
- (gh->gh_owner) ? (long)gh->gh_owner->pid : -1);
- printk(KERN_INFO " gh_state = %u\n", gh->gh_state);
- printk(KERN_INFO " gh_flags =");
+ struct task_struct *gh_owner;
+
+ print_dbg(gi, " %s\n", str);
+ if (gh->gh_owner_pid) {
+ print_dbg(gi, " owner = %ld ", (long)gh->gh_owner_pid);
+ gh_owner = find_task_by_pid(gh->gh_owner_pid);
+ if (gh_owner)
+ print_dbg(gi, "(%s)\n", gh_owner->comm);
+ else
+ print_dbg(gi, "(ended)\n");
+ } else
+ print_dbg(gi, " owner = -1\n");
+ print_dbg(gi, " gh_state = %u\n", gh->gh_state);
+ print_dbg(gi, " gh_flags =");
for (x = 0; x < 32; x++)
if (gh->gh_flags & (1 << x))
- printk(" %u", x);
- printk(" \n");
- printk(KERN_INFO " error = %d\n", gh->gh_error);
- printk(KERN_INFO " gh_iflags =");
+ print_dbg(gi, " %u", x);
+ print_dbg(gi, " \n");
+ print_dbg(gi, " error = %d\n", gh->gh_error);
+ print_dbg(gi, " gh_iflags =");
for (x = 0; x < 32; x++)
if (test_bit(x, &gh->gh_iflags))
- printk(" %u", x);
- printk(" \n");
- print_symbol(KERN_INFO " initialized at: %s\n", gh->gh_ip);
+ print_dbg(gi, " %u", x);
+ print_dbg(gi, " \n");
+ gfs2_print_symbol(gi, " initialized at: %s\n", gh->gh_ip);
- error = 0;
-
- return error;
+ return 0;
}
/**
* Returns: 0 on success, -ENOBUFS when we run out of space
*/
-static int dump_inode(struct gfs2_inode *ip)
+static int dump_inode(struct glock_iter *gi, struct gfs2_inode *ip)
{
unsigned int x;
- int error = -ENOBUFS;
- printk(KERN_INFO " Inode:\n");
- printk(KERN_INFO " num = %llu %llu\n",
- (unsigned long long)ip->i_num.no_formal_ino,
- (unsigned long long)ip->i_num.no_addr);
- printk(KERN_INFO " type = %u\n", IF2DT(ip->i_inode.i_mode));
- printk(KERN_INFO " i_flags =");
+ print_dbg(gi, " Inode:\n");
+ print_dbg(gi, " num = %llu/%llu\n",
+ ip->i_num.no_formal_ino, ip->i_num.no_addr);
+ print_dbg(gi, " type = %u\n", IF2DT(ip->i_inode.i_mode));
+ print_dbg(gi, " i_flags =");
for (x = 0; x < 32; x++)
if (test_bit(x, &ip->i_flags))
- printk(" %u", x);
- printk(" \n");
-
- error = 0;
-
- return error;
+ print_dbg(gi, " %u", x);
+ print_dbg(gi, " \n");
+ return 0;
}
/**
* Returns: 0 on success, -ENOBUFS when we run out of space
*/
-static int dump_glock(struct gfs2_glock *gl)
+static int dump_glock(struct glock_iter *gi, struct gfs2_glock *gl)
{
struct gfs2_holder *gh;
unsigned int x;
int error = -ENOBUFS;
+ struct task_struct *gl_owner;
spin_lock(&gl->gl_spin);
- printk(KERN_INFO "Glock 0x%p (%u, %llu)\n", gl, gl->gl_name.ln_type,
- (unsigned long long)gl->gl_name.ln_number);
- printk(KERN_INFO " gl_flags =");
+ print_dbg(gi, "Glock 0x%p (%u, %llu)\n", gl, gl->gl_name.ln_type,
+ (unsigned long long)gl->gl_name.ln_number);
+ print_dbg(gi, " gl_flags =");
for (x = 0; x < 32; x++) {
if (test_bit(x, &gl->gl_flags))
- printk(" %u", x);
- }
- printk(" \n");
- printk(KERN_INFO " gl_ref = %d\n", atomic_read(&gl->gl_ref));
- printk(KERN_INFO " gl_state = %u\n", gl->gl_state);
- printk(KERN_INFO " gl_owner = %s\n", gl->gl_owner->comm);
- print_symbol(KERN_INFO " gl_ip = %s\n", gl->gl_ip);
- printk(KERN_INFO " req_gh = %s\n", (gl->gl_req_gh) ? "yes" : "no");
- printk(KERN_INFO " req_bh = %s\n", (gl->gl_req_bh) ? "yes" : "no");
- printk(KERN_INFO " lvb_count = %d\n", atomic_read(&gl->gl_lvb_count));
- printk(KERN_INFO " object = %s\n", (gl->gl_object) ? "yes" : "no");
- printk(KERN_INFO " le = %s\n",
+ print_dbg(gi, " %u", x);
+ }
+ if (!test_bit(GLF_LOCK, &gl->gl_flags))
+ print_dbg(gi, " (unlocked)");
+ print_dbg(gi, " \n");
+ print_dbg(gi, " gl_ref = %d\n", atomic_read(&gl->gl_ref));
+ print_dbg(gi, " gl_state = %u\n", gl->gl_state);
+ if (gl->gl_owner_pid) {
+ gl_owner = find_task_by_pid(gl->gl_owner_pid);
+ if (gl_owner)
+ print_dbg(gi, " gl_owner = pid %d (%s)\n",
+ gl->gl_owner_pid, gl_owner->comm);
+ else
+ print_dbg(gi, " gl_owner = %d (ended)\n",
+ gl->gl_owner_pid);
+ } else
+ print_dbg(gi, " gl_owner = -1\n");
+ print_dbg(gi, " gl_ip = %lu\n", gl->gl_ip);
+ print_dbg(gi, " req_gh = %s\n", (gl->gl_req_gh) ? "yes" : "no");
+ print_dbg(gi, " req_bh = %s\n", (gl->gl_req_bh) ? "yes" : "no");
+ print_dbg(gi, " lvb_count = %d\n", atomic_read(&gl->gl_lvb_count));
+ print_dbg(gi, " object = %s\n", (gl->gl_object) ? "yes" : "no");
+ print_dbg(gi, " le = %s\n",
(list_empty(&gl->gl_le.le_list)) ? "no" : "yes");
- printk(KERN_INFO " reclaim = %s\n",
- (list_empty(&gl->gl_reclaim)) ? "no" : "yes");
+ print_dbg(gi, " reclaim = %s\n",
+ (list_empty(&gl->gl_reclaim)) ? "no" : "yes");
if (gl->gl_aspace)
- printk(KERN_INFO " aspace = 0x%p nrpages = %lu\n", gl->gl_aspace,
- gl->gl_aspace->i_mapping->nrpages);
+ print_dbg(gi, " aspace = 0x%p nrpages = %lu\n", gl->gl_aspace,
+ gl->gl_aspace->i_mapping->nrpages);
else
- printk(KERN_INFO " aspace = no\n");
- printk(KERN_INFO " ail = %d\n", atomic_read(&gl->gl_ail_count));
+ print_dbg(gi, " aspace = no\n");
+ print_dbg(gi, " ail = %d\n", atomic_read(&gl->gl_ail_count));
if (gl->gl_req_gh) {
- error = dump_holder("Request", gl->gl_req_gh);
+ error = dump_holder(gi, "Request", gl->gl_req_gh);
if (error)
goto out;
}
list_for_each_entry(gh, &gl->gl_holders, gh_list) {
- error = dump_holder("Holder", gh);
+ error = dump_holder(gi, "Holder", gh);
if (error)
goto out;
}
list_for_each_entry(gh, &gl->gl_waiters1, gh_list) {
- error = dump_holder("Waiter1", gh);
- if (error)
- goto out;
- }
- list_for_each_entry(gh, &gl->gl_waiters2, gh_list) {
- error = dump_holder("Waiter2", gh);
+ error = dump_holder(gi, "Waiter1", gh);
if (error)
goto out;
}
list_for_each_entry(gh, &gl->gl_waiters3, gh_list) {
- error = dump_holder("Waiter3", gh);
+ error = dump_holder(gi, "Waiter3", gh);
if (error)
goto out;
}
+ if (test_bit(GLF_DEMOTE, &gl->gl_flags)) {
+ print_dbg(gi, " Demotion req to state %u (%llu uS ago)\n",
+ gl->gl_demote_state,
+ (u64)(jiffies - gl->gl_demote_time)*(1000000/HZ));
+ }
if (gl->gl_ops == &gfs2_inode_glops && gl->gl_object) {
if (!test_bit(GLF_LOCK, &gl->gl_flags) &&
- list_empty(&gl->gl_holders)) {
- error = dump_inode(gl->gl_object);
+ list_empty(&gl->gl_holders)) {
+ error = dump_inode(gi, gl->gl_object);
if (error)
goto out;
} else {
error = -ENOBUFS;
- printk(KERN_INFO " Inode: busy\n");
+ print_dbg(gi, " Inode: busy\n");
}
}
if (gl->gl_sbd != sdp)
continue;
- error = dump_glock(gl);
+ error = dump_glock(NULL, gl);
if (error)
break;
}
return 0;
}
+static int gfs2_glock_iter_next(struct glock_iter *gi)
+{
+ read_lock(gl_lock_addr(gi->hash));
+ while (1) {
+ if (!gi->hb_list) { /* If we don't have a hash bucket yet */
+ gi->hb_list = &gl_hash_table[gi->hash].hb_list;
+ if (hlist_empty(gi->hb_list)) {
+ read_unlock(gl_lock_addr(gi->hash));
+ gi->hash++;
+ read_lock(gl_lock_addr(gi->hash));
+ gi->hb_list = NULL;
+ if (gi->hash >= GFS2_GL_HASH_SIZE) {
+ read_unlock(gl_lock_addr(gi->hash));
+ return 1;
+ }
+ else
+ continue;
+ }
+ if (!hlist_empty(gi->hb_list)) {
+ gi->gl = list_entry(gi->hb_list->first,
+ struct gfs2_glock,
+ gl_list);
+ }
+ } else {
+ if (gi->gl->gl_list.next == NULL) {
+ read_unlock(gl_lock_addr(gi->hash));
+ gi->hash++;
+ read_lock(gl_lock_addr(gi->hash));
+ gi->hb_list = NULL;
+ continue;
+ }
+ gi->gl = list_entry(gi->gl->gl_list.next,
+ struct gfs2_glock, gl_list);
+ }
+ if (gi->gl)
+ break;
+ }
+ read_unlock(gl_lock_addr(gi->hash));
+ return 0;
+}
+
+static void gfs2_glock_iter_free(struct glock_iter *gi)
+{
+ kfree(gi);
+}
+
+static struct glock_iter *gfs2_glock_iter_init(struct gfs2_sbd *sdp)
+{
+ struct glock_iter *gi;
+
+ gi = kmalloc(sizeof (*gi), GFP_KERNEL);
+ if (!gi)
+ return NULL;
+
+ gi->sdp = sdp;
+ gi->hash = 0;
+ gi->gl = NULL;
+ gi->hb_list = NULL;
+ gi->seq = NULL;
+ memset(gi->string, 0, sizeof(gi->string));
+
+ if (gfs2_glock_iter_next(gi)) {
+ gfs2_glock_iter_free(gi);
+ return NULL;
+ }
+
+ return gi;
+}
+
+static void *gfs2_glock_seq_start(struct seq_file *file, loff_t *pos)
+{
+ struct glock_iter *gi;
+ loff_t n = *pos;
+
+ gi = gfs2_glock_iter_init(file->private);
+ if (!gi)
+ return NULL;
+
+ while (n--) {
+ if (gfs2_glock_iter_next(gi)) {
+ gfs2_glock_iter_free(gi);
+ return NULL;
+ }
+ }
+
+ return gi;
+}
+
+static void *gfs2_glock_seq_next(struct seq_file *file, void *iter_ptr,
+ loff_t *pos)
+{
+ struct glock_iter *gi = iter_ptr;
+
+ (*pos)++;
+
+ if (gfs2_glock_iter_next(gi)) {
+ gfs2_glock_iter_free(gi);
+ return NULL;
+ }
+
+ return gi;
+}
+
+static void gfs2_glock_seq_stop(struct seq_file *file, void *iter_ptr)
+{
+ /* nothing for now */
+}
+
+static int gfs2_glock_seq_show(struct seq_file *file, void *iter_ptr)
+{
+ struct glock_iter *gi = iter_ptr;
+
+ gi->seq = file;
+ dump_glock(gi, gi->gl);
+
+ return 0;
+}
+
+static struct seq_operations gfs2_glock_seq_ops = {
+ .start = gfs2_glock_seq_start,
+ .next = gfs2_glock_seq_next,
+ .stop = gfs2_glock_seq_stop,
+ .show = gfs2_glock_seq_show,
+};
+
+static int gfs2_debugfs_open(struct inode *inode, struct file *file)
+{
+ struct seq_file *seq;
+ int ret;
+
+ ret = seq_open(file, &gfs2_glock_seq_ops);
+ if (ret)
+ return ret;
+
+ seq = file->private_data;
+ seq->private = inode->i_private;
+
+ return 0;
+}
+
+static const struct file_operations gfs2_debug_fops = {
+ .owner = THIS_MODULE,
+ .open = gfs2_debugfs_open,
+ .read = seq_read,
+ .llseek = seq_lseek,
+ .release = seq_release
+};
+
+int gfs2_create_debugfs_file(struct gfs2_sbd *sdp)
+{
+ sdp->debugfs_dir = debugfs_create_dir(sdp->sd_table_name, gfs2_root);
+ if (!sdp->debugfs_dir)
+ return -ENOMEM;
+ sdp->debugfs_dentry_glocks = debugfs_create_file("glocks",
+ S_IFREG | S_IRUGO,
+ sdp->debugfs_dir, sdp,
+ &gfs2_debug_fops);
+ if (!sdp->debugfs_dentry_glocks)
+ return -ENOMEM;
+
+ return 0;
+}
+
+void gfs2_delete_debugfs_file(struct gfs2_sbd *sdp)
+{
+ if (sdp && sdp->debugfs_dir) {
+ if (sdp->debugfs_dentry_glocks) {
+ debugfs_remove(sdp->debugfs_dentry_glocks);
+ sdp->debugfs_dentry_glocks = NULL;
+ }
+ debugfs_remove(sdp->debugfs_dir);
+ sdp->debugfs_dir = NULL;
+ }
+}
+
+int gfs2_register_debugfs(void)
+{
+ gfs2_root = debugfs_create_dir("gfs2", NULL);
+ return gfs2_root ? 0 : -ENOMEM;
+}
+
+void gfs2_unregister_debugfs(void)
+{
+ debugfs_remove(gfs2_root);
+ gfs2_root = NULL;
+}
projects / cascardo / linux.git / blobdiff