linux/fs/dlm/debug_fs.c
Alexander Aring e91313591b dlm: use rwlock for rsb hash table
The conversion to rhashtable introduced a hash table lock per lockspace,
in place of per bucket locks.  To make this more scalable, switch to
using a rwlock for hash table access.  The common case fast path uses
it as a read lock.

Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
2024-04-16 14:45:31 -05:00

827 lines
19 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/******************************************************************************
*******************************************************************************
**
** Copyright (C) 2005-2009 Red Hat, Inc. All rights reserved.
**
**
*******************************************************************************
******************************************************************************/
#include <linux/pagemap.h>
#include <linux/seq_file.h>
#include <linux/init.h>
#include <linux/ctype.h>
#include <linux/debugfs.h>
#include <linux/slab.h>
#include "dlm_internal.h"
#include "midcomms.h"
#include "lock.h"
#include "ast.h"
#define DLM_DEBUG_BUF_LEN 4096
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)
{
switch (mode) {
case DLM_LOCK_IV:
return "--";
case DLM_LOCK_NL:
return "NL";
case DLM_LOCK_CR:
return "CR";
case DLM_LOCK_CW:
return "CW";
case DLM_LOCK_PR:
return "PR";
case DLM_LOCK_PW:
return "PW";
case DLM_LOCK_EX:
return "EX";
default:
return "??";
}
}
static void print_format1_lock(struct seq_file *s, struct dlm_lkb *lkb,
struct dlm_rsb *res)
{
seq_printf(s, "%08x %s", lkb->lkb_id, print_lockmode(lkb->lkb_grmode));
if (lkb->lkb_status == DLM_LKSTS_CONVERT ||
lkb->lkb_status == DLM_LKSTS_WAITING)
seq_printf(s, " (%s)", print_lockmode(lkb->lkb_rqmode));
if (lkb->lkb_nodeid) {
if (lkb->lkb_nodeid != res->res_nodeid)
seq_printf(s, " Remote: %3d %08x", lkb->lkb_nodeid,
lkb->lkb_remid);
else
seq_printf(s, " Master: %08x", lkb->lkb_remid);
}
if (lkb->lkb_wait_type)
seq_printf(s, " wait_type: %d", lkb->lkb_wait_type);
seq_putc(s, '\n');
}
static void print_format1(struct dlm_rsb *res, struct seq_file *s)
{
struct dlm_lkb *lkb;
int i, lvblen = res->res_ls->ls_lvblen, recover_list, root_list;
lock_rsb(res);
seq_printf(s, "\nResource %p Name (len=%d) \"", res, res->res_length);
for (i = 0; i < res->res_length; i++) {
if (isprint(res->res_name[i]))
seq_printf(s, "%c", res->res_name[i]);
else
seq_printf(s, "%c", '.');
}
if (res->res_nodeid > 0)
seq_printf(s, "\"\nLocal Copy, Master is node %d\n",
res->res_nodeid);
else if (res->res_nodeid == 0)
seq_puts(s, "\"\nMaster Copy\n");
else if (res->res_nodeid == -1)
seq_printf(s, "\"\nLooking up master (lkid %x)\n",
res->res_first_lkid);
else
seq_printf(s, "\"\nInvalid master %d\n", res->res_nodeid);
if (seq_has_overflowed(s))
goto out;
/* Print the LVB: */
if (res->res_lvbptr) {
seq_puts(s, "LVB: ");
for (i = 0; i < lvblen; i++) {
if (i == lvblen / 2)
seq_puts(s, "\n ");
seq_printf(s, "%02x ",
(unsigned char) res->res_lvbptr[i]);
}
if (rsb_flag(res, RSB_VALNOTVALID))
seq_puts(s, " (INVALID)");
seq_putc(s, '\n');
if (seq_has_overflowed(s))
goto out;
}
root_list = !list_empty(&res->res_root_list);
recover_list = !list_empty(&res->res_recover_list);
if (root_list || recover_list) {
seq_printf(s, "Recovery: root %d recover %d flags %lx count %d\n",
root_list, recover_list,
res->res_flags, res->res_recover_locks_count);
}
/* Print the locks attached to this resource */
seq_puts(s, "Granted Queue\n");
list_for_each_entry(lkb, &res->res_grantqueue, lkb_statequeue) {
print_format1_lock(s, lkb, res);
if (seq_has_overflowed(s))
goto out;
}
seq_puts(s, "Conversion Queue\n");
list_for_each_entry(lkb, &res->res_convertqueue, lkb_statequeue) {
print_format1_lock(s, lkb, res);
if (seq_has_overflowed(s))
goto out;
}
seq_puts(s, "Waiting Queue\n");
list_for_each_entry(lkb, &res->res_waitqueue, lkb_statequeue) {
print_format1_lock(s, lkb, res);
if (seq_has_overflowed(s))
goto out;
}
if (list_empty(&res->res_lookup))
goto out;
seq_puts(s, "Lookup Queue\n");
list_for_each_entry(lkb, &res->res_lookup, lkb_rsb_lookup) {
seq_printf(s, "%08x %s",
lkb->lkb_id, print_lockmode(lkb->lkb_rqmode));
if (lkb->lkb_wait_type)
seq_printf(s, " wait_type: %d", lkb->lkb_wait_type);
seq_putc(s, '\n');
if (seq_has_overflowed(s))
goto out;
}
out:
unlock_rsb(res);
}
static void print_format2_lock(struct seq_file *s, struct dlm_lkb *lkb,
struct dlm_rsb *r)
{
u64 xid = 0;
u64 us;
if (test_bit(DLM_DFL_USER_BIT, &lkb->lkb_dflags)) {
if (lkb->lkb_ua)
xid = lkb->lkb_ua->xid;
}
/* microseconds since lkb was added to current queue */
us = ktime_to_us(ktime_sub(ktime_get(), lkb->lkb_timestamp));
/* id nodeid remid pid xid exflags flags sts grmode rqmode time_us
r_nodeid r_len r_name */
seq_printf(s, "%x %d %x %u %llu %x %x %d %d %d %llu %u %d \"%s\"\n",
lkb->lkb_id,
lkb->lkb_nodeid,
lkb->lkb_remid,
lkb->lkb_ownpid,
(unsigned long long)xid,
lkb->lkb_exflags,
dlm_iflags_val(lkb),
lkb->lkb_status,
lkb->lkb_grmode,
lkb->lkb_rqmode,
(unsigned long long)us,
r->res_nodeid,
r->res_length,
r->res_name);
}
static void print_format2(struct dlm_rsb *r, struct seq_file *s)
{
struct dlm_lkb *lkb;
lock_rsb(r);
list_for_each_entry(lkb, &r->res_grantqueue, lkb_statequeue) {
print_format2_lock(s, lkb, r);
if (seq_has_overflowed(s))
goto out;
}
list_for_each_entry(lkb, &r->res_convertqueue, lkb_statequeue) {
print_format2_lock(s, lkb, r);
if (seq_has_overflowed(s))
goto out;
}
list_for_each_entry(lkb, &r->res_waitqueue, lkb_statequeue) {
print_format2_lock(s, lkb, r);
if (seq_has_overflowed(s))
goto out;
}
out:
unlock_rsb(r);
}
static void print_format3_lock(struct seq_file *s, struct dlm_lkb *lkb,
int rsb_lookup)
{
u64 xid = 0;
if (test_bit(DLM_DFL_USER_BIT, &lkb->lkb_dflags)) {
if (lkb->lkb_ua)
xid = lkb->lkb_ua->xid;
}
seq_printf(s, "lkb %x %d %x %u %llu %x %x %d %d %d %d %d %d %u %llu %llu\n",
lkb->lkb_id,
lkb->lkb_nodeid,
lkb->lkb_remid,
lkb->lkb_ownpid,
(unsigned long long)xid,
lkb->lkb_exflags,
dlm_iflags_val(lkb),
lkb->lkb_status,
lkb->lkb_grmode,
lkb->lkb_rqmode,
lkb->lkb_last_bast_cb_mode,
rsb_lookup,
lkb->lkb_wait_type,
lkb->lkb_lvbseq,
(unsigned long long)ktime_to_ns(lkb->lkb_timestamp),
(unsigned long long)ktime_to_ns(lkb->lkb_last_bast_time));
}
static void print_format3(struct dlm_rsb *r, struct seq_file *s)
{
struct dlm_lkb *lkb;
int i, lvblen = r->res_ls->ls_lvblen;
int print_name = 1;
lock_rsb(r);
seq_printf(s, "rsb %p %d %x %lx %d %d %u %d ",
r,
r->res_nodeid,
r->res_first_lkid,
r->res_flags,
!list_empty(&r->res_root_list),
!list_empty(&r->res_recover_list),
r->res_recover_locks_count,
r->res_length);
if (seq_has_overflowed(s))
goto out;
for (i = 0; i < r->res_length; i++) {
if (!isascii(r->res_name[i]) || !isprint(r->res_name[i]))
print_name = 0;
}
seq_puts(s, print_name ? "str " : "hex");
for (i = 0; i < r->res_length; i++) {
if (print_name)
seq_printf(s, "%c", r->res_name[i]);
else
seq_printf(s, " %02x", (unsigned char)r->res_name[i]);
}
seq_putc(s, '\n');
if (seq_has_overflowed(s))
goto out;
if (!r->res_lvbptr)
goto do_locks;
seq_printf(s, "lvb %u %d", r->res_lvbseq, lvblen);
for (i = 0; i < lvblen; i++)
seq_printf(s, " %02x", (unsigned char)r->res_lvbptr[i]);
seq_putc(s, '\n');
if (seq_has_overflowed(s))
goto out;
do_locks:
list_for_each_entry(lkb, &r->res_grantqueue, lkb_statequeue) {
print_format3_lock(s, lkb, 0);
if (seq_has_overflowed(s))
goto out;
}
list_for_each_entry(lkb, &r->res_convertqueue, lkb_statequeue) {
print_format3_lock(s, lkb, 0);
if (seq_has_overflowed(s))
goto out;
}
list_for_each_entry(lkb, &r->res_waitqueue, lkb_statequeue) {
print_format3_lock(s, lkb, 0);
if (seq_has_overflowed(s))
goto out;
}
list_for_each_entry(lkb, &r->res_lookup, lkb_rsb_lookup) {
print_format3_lock(s, lkb, 1);
if (seq_has_overflowed(s))
goto out;
}
out:
unlock_rsb(r);
}
static void print_format4(struct dlm_rsb *r, struct seq_file *s)
{
int our_nodeid = dlm_our_nodeid();
int print_name = 1;
int i;
lock_rsb(r);
seq_printf(s, "rsb %p %d %d %d %d %lu %lx %d ",
r,
r->res_nodeid,
r->res_master_nodeid,
r->res_dir_nodeid,
our_nodeid,
r->res_toss_time,
r->res_flags,
r->res_length);
for (i = 0; i < r->res_length; i++) {
if (!isascii(r->res_name[i]) || !isprint(r->res_name[i]))
print_name = 0;
}
seq_puts(s, print_name ? "str " : "hex");
for (i = 0; i < r->res_length; i++) {
if (print_name)
seq_printf(s, "%c", r->res_name[i]);
else
seq_printf(s, " %02x", (unsigned char)r->res_name[i]);
}
seq_putc(s, '\n');
unlock_rsb(r);
}
static const struct seq_operations format1_seq_ops;
static const struct seq_operations format2_seq_ops;
static const struct seq_operations format3_seq_ops;
static const struct seq_operations format4_seq_ops;
/*
* If the buffer is full, seq_printf can be called again, but it
* does nothing. So, the these printing routines periodically check
* seq_has_overflowed to avoid wasting too much time trying to print to
* a full buffer.
*/
static int table_seq_show(struct seq_file *seq, void *iter_ptr)
{
struct dlm_rsb *rsb = list_entry(iter_ptr, struct dlm_rsb, res_rsbs_list);
if (seq->op == &format1_seq_ops)
print_format1(rsb, seq);
else if (seq->op == &format2_seq_ops)
print_format2(rsb, seq);
else if (seq->op == &format3_seq_ops)
print_format3(rsb, seq);
else if (seq->op == &format4_seq_ops)
print_format4(rsb, seq);
return 0;
}
static void *table_seq_start(struct seq_file *seq, loff_t *pos)
{
struct dlm_ls *ls = seq->private;
struct list_head *list;
if (!*pos) {
if (seq->op == &format2_seq_ops)
seq_puts(seq, "id nodeid remid pid xid exflags flags sts grmode rqmode time_ms r_nodeid r_len r_name\n");
else if (seq->op == &format3_seq_ops)
seq_puts(seq, "rsb ptr nodeid first_lkid flags !root_list_empty !recover_list_empty recover_locks_count len\n");
else if (seq->op == &format4_seq_ops)
seq_puts(seq, "rsb ptr nodeid master_nodeid dir_nodeid our_nodeid toss_time flags len str|hex name\n");
}
if (seq->op == &format4_seq_ops)
list = &ls->ls_toss;
else
list = &ls->ls_keep;
read_lock_bh(&ls->ls_rsbtbl_lock);
return seq_list_start(list, *pos);
}
static void *table_seq_next(struct seq_file *seq, void *iter_ptr, loff_t *pos)
{
struct dlm_ls *ls = seq->private;
struct list_head *list;
if (seq->op == &format4_seq_ops)
list = &ls->ls_toss;
else
list = &ls->ls_keep;
return seq_list_next(iter_ptr, list, pos);
}
static void table_seq_stop(struct seq_file *seq, void *iter_ptr)
{
struct dlm_ls *ls = seq->private;
read_unlock_bh(&ls->ls_rsbtbl_lock);
}
static const struct seq_operations format1_seq_ops = {
.start = table_seq_start,
.next = table_seq_next,
.stop = table_seq_stop,
.show = table_seq_show,
};
static const struct seq_operations format2_seq_ops = {
.start = table_seq_start,
.next = table_seq_next,
.stop = table_seq_stop,
.show = table_seq_show,
};
static const struct seq_operations format3_seq_ops = {
.start = table_seq_start,
.next = table_seq_next,
.stop = table_seq_stop,
.show = table_seq_show,
};
static const struct seq_operations format4_seq_ops = {
.start = table_seq_start,
.next = table_seq_next,
.stop = table_seq_stop,
.show = table_seq_show,
};
static const struct file_operations format1_fops;
static const struct file_operations format2_fops;
static const struct file_operations format3_fops;
static const struct file_operations format4_fops;
static int table_open1(struct inode *inode, struct file *file)
{
struct seq_file *seq;
int ret;
ret = seq_open(file, &format1_seq_ops);
if (ret)
return ret;
seq = file->private_data;
seq->private = inode->i_private; /* the dlm_ls */
return 0;
}
static int table_open2(struct inode *inode, struct file *file)
{
struct seq_file *seq;
int ret;
ret = seq_open(file, &format2_seq_ops);
if (ret)
return ret;
seq = file->private_data;
seq->private = inode->i_private; /* the dlm_ls */
return 0;
}
static ssize_t table_write2(struct file *file, const char __user *user_buf,
size_t count, loff_t *ppos)
{
struct seq_file *seq = file->private_data;
int n, len, lkb_nodeid, lkb_status, error;
char name[DLM_RESNAME_MAXLEN + 1] = {};
struct dlm_ls *ls = seq->private;
unsigned int lkb_flags;
char buf[256] = {};
uint32_t lkb_id;
if (copy_from_user(buf, user_buf,
min_t(size_t, sizeof(buf) - 1, count)))
return -EFAULT;
n = sscanf(buf, "%x %" __stringify(DLM_RESNAME_MAXLEN) "s %x %d %d",
&lkb_id, name, &lkb_flags, &lkb_nodeid, &lkb_status);
if (n != 5)
return -EINVAL;
len = strnlen(name, DLM_RESNAME_MAXLEN);
error = dlm_debug_add_lkb(ls, lkb_id, name, len, lkb_flags,
lkb_nodeid, lkb_status);
if (error)
return error;
return count;
}
static int table_open3(struct inode *inode, struct file *file)
{
struct seq_file *seq;
int ret;
ret = seq_open(file, &format3_seq_ops);
if (ret)
return ret;
seq = file->private_data;
seq->private = inode->i_private; /* the dlm_ls */
return 0;
}
static int table_open4(struct inode *inode, struct file *file)
{
struct seq_file *seq;
int ret;
ret = seq_open(file, &format4_seq_ops);
if (ret)
return ret;
seq = file->private_data;
seq->private = inode->i_private; /* the dlm_ls */
return 0;
}
static const struct file_operations format1_fops = {
.owner = THIS_MODULE,
.open = table_open1,
.read = seq_read,
.llseek = seq_lseek,
.release = seq_release
};
static const struct file_operations format2_fops = {
.owner = THIS_MODULE,
.open = table_open2,
.read = seq_read,
.write = table_write2,
.llseek = seq_lseek,
.release = seq_release
};
static const struct file_operations format3_fops = {
.owner = THIS_MODULE,
.open = table_open3,
.read = seq_read,
.llseek = seq_lseek,
.release = seq_release
};
static const struct file_operations format4_fops = {
.owner = THIS_MODULE,
.open = table_open4,
.read = seq_read,
.llseek = seq_lseek,
.release = seq_release
};
/*
* dump lkb's on the ls_waiters list
*/
static ssize_t waiters_read(struct file *file, char __user *userbuf,
size_t count, loff_t *ppos)
{
struct dlm_ls *ls = file->private_data;
struct dlm_lkb *lkb;
size_t len = DLM_DEBUG_BUF_LEN, pos = 0, ret, rv;
mutex_lock(&debug_buf_lock);
ret = dlm_lock_recovery_try(ls);
if (!ret) {
rv = -EAGAIN;
goto out;
}
spin_lock_bh(&ls->ls_waiters_lock);
memset(debug_buf, 0, sizeof(debug_buf));
list_for_each_entry(lkb, &ls->ls_waiters, lkb_wait_reply) {
ret = snprintf(debug_buf + pos, len - pos, "%x %d %d %s\n",
lkb->lkb_id, lkb->lkb_wait_type,
lkb->lkb_nodeid, lkb->lkb_resource->res_name);
if (ret >= len - pos)
break;
pos += ret;
}
spin_unlock_bh(&ls->ls_waiters_lock);
dlm_unlock_recovery(ls);
rv = simple_read_from_buffer(userbuf, count, ppos, debug_buf, pos);
out:
mutex_unlock(&debug_buf_lock);
return rv;
}
static ssize_t waiters_write(struct file *file, const char __user *user_buf,
size_t count, loff_t *ppos)
{
struct dlm_ls *ls = file->private_data;
int mstype, to_nodeid;
char buf[128] = {};
uint32_t lkb_id;
int n, error;
if (copy_from_user(buf, user_buf,
min_t(size_t, sizeof(buf) - 1, count)))
return -EFAULT;
n = sscanf(buf, "%x %d %d", &lkb_id, &mstype, &to_nodeid);
if (n != 3)
return -EINVAL;
error = dlm_lock_recovery_try(ls);
if (!error)
return -EAGAIN;
error = dlm_debug_add_lkb_to_waiters(ls, lkb_id, mstype, to_nodeid);
dlm_unlock_recovery(ls);
if (error)
return error;
return count;
}
static const struct file_operations waiters_fops = {
.owner = THIS_MODULE,
.open = simple_open,
.read = waiters_read,
.write = waiters_write,
.llseek = default_llseek,
};
void dlm_delete_debug_file(struct dlm_ls *ls)
{
debugfs_remove(ls->ls_debug_rsb_dentry);
debugfs_remove(ls->ls_debug_waiters_dentry);
debugfs_remove(ls->ls_debug_locks_dentry);
debugfs_remove(ls->ls_debug_all_dentry);
debugfs_remove(ls->ls_debug_toss_dentry);
debugfs_remove(ls->ls_debug_queued_asts_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);
static ssize_t dlm_rawmsg_write(struct file *fp, const char __user *user_buf,
size_t count, loff_t *ppos)
{
void *buf;
int ret;
if (count > PAGE_SIZE || count < sizeof(struct dlm_header))
return -EINVAL;
buf = kmalloc(PAGE_SIZE, GFP_NOFS);
if (!buf)
return -ENOMEM;
if (copy_from_user(buf, user_buf, count)) {
ret = -EFAULT;
goto out;
}
ret = dlm_midcomms_rawmsg_send(fp->private_data, buf, count);
if (ret)
goto out;
kfree(buf);
return count;
out:
kfree(buf);
return ret;
}
static const struct file_operations dlm_rawmsg_fops = {
.open = simple_open,
.write = dlm_rawmsg_write,
.llseek = no_llseek,
};
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);
debugfs_create_file("rawmsg", 0200, d_node, data, &dlm_rawmsg_fops);
return d_node;
}
void dlm_delete_debug_comms_file(void *ctx)
{
debugfs_remove(ctx);
}
void dlm_create_debug_file(struct dlm_ls *ls)
{
/* Reserve enough space for the longest file name */
char name[DLM_LOCKSPACE_LEN + sizeof("_queued_asts")];
/* format 1 */
ls->ls_debug_rsb_dentry = debugfs_create_file(ls->ls_name,
S_IFREG | S_IRUGO,
dlm_root,
ls,
&format1_fops);
/* format 2 */
snprintf(name, sizeof(name), "%s_locks", ls->ls_name);
ls->ls_debug_locks_dentry = debugfs_create_file(name,
0644,
dlm_root,
ls,
&format2_fops);
/* format 3 */
snprintf(name, sizeof(name), "%s_all", ls->ls_name);
ls->ls_debug_all_dentry = debugfs_create_file(name,
S_IFREG | S_IRUGO,
dlm_root,
ls,
&format3_fops);
/* format 4 */
snprintf(name, sizeof(name), "%s_toss", ls->ls_name);
ls->ls_debug_toss_dentry = debugfs_create_file(name,
S_IFREG | S_IRUGO,
dlm_root,
ls,
&format4_fops);
snprintf(name, sizeof(name), "%s_waiters", ls->ls_name);
ls->ls_debug_waiters_dentry = debugfs_create_file(name,
0644,
dlm_root,
ls,
&waiters_fops);
}
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)
{
debugfs_remove(dlm_root);
}