drivers/staging/lustre/lnet/libcfs/debug.c - arm/linux - Git at Google

 /*
  * GPL HEADER START
  *
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License version 2 only,
  * as published by the Free Software Foundation.
  *
  * This program is distributed in the hope that it will be useful, but
  * WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  * General Public License version 2 for more details (a copy is included
  * in the LICENSE file that accompanied this code).
  *
  * You should have received a copy of the GNU General Public License
  * version 2 along with this program; If not, see
  * http://www.gnu.org/licenses/gpl-2.0.html
  *
  * GPL HEADER END
  */
 /*
  * Copyright (c) 2008, 2010, Oracle and/or its affiliates. All rights reserved.
  * Use is subject to license terms.
  *
  * Copyright (c) 2011, 2012, Intel Corporation.
  */
 /*
  * This file is part of Lustre, http://www.lustre.org/
  * Lustre is a trademark of Sun Microsystems, Inc.
  *
  * libcfs/libcfs/debug.c
  *
  * Author: Phil Schwan <phil@clusterfs.com>
  *
  */

 # define DEBUG_SUBSYSTEM S_LNET

 #include <linux/libcfs/libcfs.h>
 #include "tracefile.h"

 static char debug_file_name[1024];

 unsigned int libcfs_subsystem_debug = ~0;
 EXPORT_SYMBOL(libcfs_subsystem_debug);
 module_param(libcfs_subsystem_debug, int, 0644);
 MODULE_PARM_DESC(libcfs_subsystem_debug, "Lustre kernel debug subsystem mask");

 unsigned int libcfs_debug = (D_CANTMASK |
 			     D_NETERROR | D_HA | D_CONFIG | D_IOCTL);
 EXPORT_SYMBOL(libcfs_debug);
 module_param(libcfs_debug, int, 0644);
 MODULE_PARM_DESC(libcfs_debug, "Lustre kernel debug mask");

 static int libcfs_param_debug_mb_set(const char *val,
 				     const struct kernel_param *kp)
 {
 	int rc;
 	unsigned int num;

 	rc = kstrtouint(val, 0, &num);
 	if (rc < 0)
 		return rc;

 	if (!*((unsigned int *)kp->arg)) {
 		*((unsigned int *)kp->arg) = num;
 		return 0;
 	}

 	rc = cfs_trace_set_debug_mb(num);

 	if (!rc)
 		*((unsigned int *)kp->arg) = cfs_trace_get_debug_mb();

 	return rc;
 }

 /* While debug_mb setting look like unsigned int, in fact
  * it needs quite a bunch of extra processing, so we define special
  * debugmb parameter type with corresponding methods to handle this case
  */
 static const struct kernel_param_ops param_ops_debugmb = {
 	.set = libcfs_param_debug_mb_set,
 	.get = param_get_uint,
 };

 #define param_check_debugmb(name, p) \
 		__param_check(name, p, unsigned int)

 static unsigned int libcfs_debug_mb;
 module_param(libcfs_debug_mb, debugmb, 0644);
 MODULE_PARM_DESC(libcfs_debug_mb, "Total debug buffer size.");

 unsigned int libcfs_printk = D_CANTMASK;
 module_param(libcfs_printk, uint, 0644);
 MODULE_PARM_DESC(libcfs_printk, "Lustre kernel debug console mask");

 unsigned int libcfs_console_ratelimit = 1;
 module_param(libcfs_console_ratelimit, uint, 0644);
 MODULE_PARM_DESC(libcfs_console_ratelimit, "Lustre kernel debug console ratelimit (0 to disable)");

 static int param_set_delay_minmax(const char *val,
 				  const struct kernel_param *kp,
 				  long min, long max)
 {
 	long d;
 	int sec;
 	int rc;

 	rc = kstrtoint(val, 0, &sec);
 	if (rc)
 		return -EINVAL;

 	d = cfs_time_seconds(sec) / 100;
 	if (d < min || d > max)
 		return -EINVAL;

 	*((unsigned int *)kp->arg) = d;

 	return 0;
 }

 static int param_get_delay(char *buffer, const struct kernel_param *kp)
 {
 	unsigned int d = *(unsigned int *)kp->arg;

 	return sprintf(buffer, "%u", (unsigned int)cfs_duration_sec(d * 100));
 }

 unsigned int libcfs_console_max_delay;
 unsigned int libcfs_console_min_delay;

 static int param_set_console_max_delay(const char *val,
 				       const struct kernel_param *kp)
 {
 	return param_set_delay_minmax(val, kp,
 				      libcfs_console_min_delay, INT_MAX);
 }

 static const struct kernel_param_ops param_ops_console_max_delay = {
 	.set = param_set_console_max_delay,
 	.get = param_get_delay,
 };

 #define param_check_console_max_delay(name, p) \
 		__param_check(name, p, unsigned int)

 module_param(libcfs_console_max_delay, console_max_delay, 0644);
 MODULE_PARM_DESC(libcfs_console_max_delay, "Lustre kernel debug console max delay (jiffies)");

 static int param_set_console_min_delay(const char *val,
 				       const struct kernel_param *kp)
 {
 	return param_set_delay_minmax(val, kp,
 				      1, libcfs_console_max_delay);
 }

 static const struct kernel_param_ops param_ops_console_min_delay = {
 	.set = param_set_console_min_delay,
 	.get = param_get_delay,
 };

 #define param_check_console_min_delay(name, p) \
 		__param_check(name, p, unsigned int)

 module_param(libcfs_console_min_delay, console_min_delay, 0644);
 MODULE_PARM_DESC(libcfs_console_min_delay, "Lustre kernel debug console min delay (jiffies)");

 static int param_set_uint_minmax(const char *val,
 				 const struct kernel_param *kp,
 				 unsigned int min, unsigned int max)
 {
 	unsigned int num;
 	int ret;

 	if (!val)
 		return -EINVAL;
 	ret = kstrtouint(val, 0, &num);
 	if (ret < 0 || num < min || num > max)
 		return -EINVAL;
 	*((unsigned int *)kp->arg) = num;
 	return 0;
 }

 static int param_set_uintpos(const char *val, const struct kernel_param *kp)
 {
 	return param_set_uint_minmax(val, kp, 1, -1);
 }

 static const struct kernel_param_ops param_ops_uintpos = {
 	.set = param_set_uintpos,
 	.get = param_get_uint,
 };

 #define param_check_uintpos(name, p) \
 		__param_check(name, p, unsigned int)

 unsigned int libcfs_console_backoff = CDEBUG_DEFAULT_BACKOFF;
 module_param(libcfs_console_backoff, uintpos, 0644);
 MODULE_PARM_DESC(libcfs_console_backoff, "Lustre kernel debug console backoff factor");

 unsigned int libcfs_debug_binary = 1;

 unsigned int libcfs_stack = 3 * THREAD_SIZE / 4;
 EXPORT_SYMBOL(libcfs_stack);

 unsigned int libcfs_catastrophe;
 EXPORT_SYMBOL(libcfs_catastrophe);

 unsigned int libcfs_panic_on_lbug = 1;
 module_param(libcfs_panic_on_lbug, uint, 0644);
 MODULE_PARM_DESC(libcfs_panic_on_lbug, "Lustre kernel panic on LBUG");

 static wait_queue_head_t debug_ctlwq;

 char libcfs_debug_file_path_arr[PATH_MAX] = LIBCFS_DEBUG_FILE_PATH_DEFAULT;

 /* We need to pass a pointer here, but elsewhere this must be a const */
 static char *libcfs_debug_file_path;
 module_param(libcfs_debug_file_path, charp, 0644);
 MODULE_PARM_DESC(libcfs_debug_file_path,
 		 "Path for dumping debug logs, set 'NONE' to prevent log dumping");

 int libcfs_panic_in_progress;

 /* libcfs_debug_token2mask() expects the returned string in lower-case */
 static const char *
 libcfs_debug_subsys2str(int subsys)
 {
 	static const char * const libcfs_debug_subsystems[] =
 		LIBCFS_DEBUG_SUBSYS_NAMES;

 	if (subsys >= ARRAY_SIZE(libcfs_debug_subsystems))
 		return NULL;

 	return libcfs_debug_subsystems[subsys];
 }

 /* libcfs_debug_token2mask() expects the returned string in lower-case */
 static const char *
 libcfs_debug_dbg2str(int debug)
 {
 	static const char * const libcfs_debug_masks[] =
 		LIBCFS_DEBUG_MASKS_NAMES;

 	if (debug >= ARRAY_SIZE(libcfs_debug_masks))
 		return NULL;

 	return libcfs_debug_masks[debug];
 }

 int
 libcfs_debug_mask2str(char *str, int size, int mask, int is_subsys)
 {
 	const char *(*fn)(int bit) = is_subsys ? libcfs_debug_subsys2str :
 						 libcfs_debug_dbg2str;
 	int len = 0;
 	const char *token;
 	int i;

 	if (!mask) {			/* "0" */
 		if (size > 0)
 			str[0] = '0';
 		len = 1;
 	} else {				/* space-separated tokens */
 		for (i = 0; i < 32; i++) {
 			if (!(mask & (1 << i)))
 				continue;

 			token = fn(i);
 			if (!token)	      /* unused bit */
 				continue;

 			if (len > 0) {		  /* separator? */
 				if (len < size)
 					str[len] = ' ';
 				len++;
 			}

 			while (*token) {
 				if (len < size)
 					str[len] = *token;
 				token++;
 				len++;
 			}
 		}
 	}

 	/* terminate 'str' */
 	if (len < size)
 		str[len] = 0;
 	else
 		str[size - 1] = 0;

 	return len;
 }

 int
 libcfs_debug_str2mask(int *mask, const char *str, int is_subsys)
 {
 	const char *(*fn)(int bit) = is_subsys ? libcfs_debug_subsys2str :
 						 libcfs_debug_dbg2str;
 	int m = 0;
 	int matched;
 	int n;
 	int t;

 	/* Allow a number for backwards compatibility */

 	for (n = strlen(str); n > 0; n--)
 		if (!isspace(str[n - 1]))
 			break;
 	matched = n;
 	t = sscanf(str, "%i%n", &m, &matched);
 	if (t >= 1 && matched == n) {
 		/* don't print warning for lctl set_param debug=0 or -1 */
 		if (m && m != -1)
 			CWARN("You are trying to use a numerical value for the mask - this will be deprecated in a future release.\n");
 		*mask = m;
 		return 0;
 	}

 	return cfs_str2mask(str, fn, mask, is_subsys ? 0 : D_CANTMASK,
 			    0xffffffff);
 }

 /**
  * Dump Lustre log to ::debug_file_path by calling tracefile_dump_all_pages()
  */
 void libcfs_debug_dumplog_internal(void *arg)
 {
 	static time64_t last_dump_time;
 	time64_t current_time;
 	void *journal_info;

 	journal_info = current->journal_info;
 	current->journal_info = NULL;
 	current_time = ktime_get_real_seconds();

 	if (strncmp(libcfs_debug_file_path_arr, "NONE", 4) &&
 	    current_time > last_dump_time) {
 		last_dump_time = current_time;
 		snprintf(debug_file_name, sizeof(debug_file_name) - 1,
 			 "%s.%lld.%ld", libcfs_debug_file_path_arr,
 			 (s64)current_time, (long)arg);
 		pr_alert("LustreError: dumping log to %s\n", debug_file_name);
 		cfs_tracefile_dump_all_pages(debug_file_name);
 		libcfs_run_debug_log_upcall(debug_file_name);
 	}

 	current->journal_info = journal_info;
 }

 static int libcfs_debug_dumplog_thread(void *arg)
 {
 	libcfs_debug_dumplog_internal(arg);
 	wake_up(&debug_ctlwq);
 	return 0;
 }

 void libcfs_debug_dumplog(void)
 {
 	wait_queue_entry_t wait;
 	struct task_struct *dumper;

 	/* we're being careful to ensure that the kernel thread is
 	 * able to set our state to running as it exits before we
 	 * get to schedule()
 	 */
 	init_waitqueue_entry(&wait, current);
 	add_wait_queue(&debug_ctlwq, &wait);

 	dumper = kthread_run(libcfs_debug_dumplog_thread,
 			     (void *)(long)current_pid(),
 			     "libcfs_debug_dumper");
 	set_current_state(TASK_INTERRUPTIBLE);
 	if (IS_ERR(dumper))
 		pr_err("LustreError: cannot start log dump thread: %ld\n",
 		       PTR_ERR(dumper));
 	else
 		schedule();

 	/* be sure to teardown if cfs_create_thread() failed */
 	remove_wait_queue(&debug_ctlwq, &wait);
 	set_current_state(TASK_RUNNING);
 }
 EXPORT_SYMBOL(libcfs_debug_dumplog);

 int libcfs_debug_init(unsigned long bufsize)
 {
 	unsigned int max = libcfs_debug_mb;
 	int rc = 0;

 	init_waitqueue_head(&debug_ctlwq);

 	if (libcfs_console_max_delay <= 0 || /* not set by user or */
 	    libcfs_console_min_delay <= 0 || /* set to invalid values */
 	    libcfs_console_min_delay >= libcfs_console_max_delay) {
 		libcfs_console_max_delay = CDEBUG_DEFAULT_MAX_DELAY;
 		libcfs_console_min_delay = CDEBUG_DEFAULT_MIN_DELAY;
 	}

 	if (libcfs_debug_file_path) {
 		strlcpy(libcfs_debug_file_path_arr,
 			libcfs_debug_file_path,
 			sizeof(libcfs_debug_file_path_arr));
 	}

 	/* If libcfs_debug_mb is set to an invalid value or uninitialized
 	 * then just make the total buffers smp_num_cpus * TCD_MAX_PAGES
 	 */
 	if (max > cfs_trace_max_debug_mb() || max < num_possible_cpus()) {
 		max = TCD_MAX_PAGES;
 	} else {
 		max = max / num_possible_cpus();
 		max <<= (20 - PAGE_SHIFT);
 	}

 	rc = cfs_tracefile_init(max);
 	if (!rc) {
 		libcfs_register_panic_notifier();
 		libcfs_debug_mb = cfs_trace_get_debug_mb();
 	}

 	return rc;
 }

 int libcfs_debug_cleanup(void)
 {
 	libcfs_unregister_panic_notifier();
 	cfs_tracefile_exit();
 	return 0;
 }

 int libcfs_debug_clear_buffer(void)
 {
 	cfs_trace_flush_pages();
 	return 0;
 }

 /* Debug markers, although printed by S_LNET should not be be marked as such. */
 #undef DEBUG_SUBSYSTEM
 #define DEBUG_SUBSYSTEM S_UNDEFINED
 int libcfs_debug_mark_buffer(const char *text)
 {
 	CDEBUG(D_TRACE,
 	       "***************************************************\n");
 	LCONSOLE(D_WARNING, "DEBUG MARKER: %s\n", text);
 	CDEBUG(D_TRACE,
 	       "***************************************************\n");

 	return 0;
 }

 #undef DEBUG_SUBSYSTEM
 #define DEBUG_SUBSYSTEM S_LNET
	/*
	* GPL HEADER START
	*
	* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
	*
	* This program is free software; you can redistribute it and/or modify
	* it under the terms of the GNU General Public License version 2 only,
	* as published by the Free Software Foundation.
	*
	* This program is distributed in the hope that it will be useful, but
	* WITHOUT ANY WARRANTY; without even the implied warranty of
	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
	* General Public License version 2 for more details (a copy is included
	* in the LICENSE file that accompanied this code).
	*
	* You should have received a copy of the GNU General Public License
	* version 2 along with this program; If not, see
	* http://www.gnu.org/licenses/gpl-2.0.html
	*
	* GPL HEADER END
	*/
	/*
	* Copyright (c) 2008, 2010, Oracle and/or its affiliates. All rights reserved.
	* Use is subject to license terms.
	*
	* Copyright (c) 2011, 2012, Intel Corporation.
	*/
	/*
	* This file is part of Lustre, http://www.lustre.org/
	* Lustre is a trademark of Sun Microsystems, Inc.
	*
	* libcfs/libcfs/debug.c
	*
	* Author: Phil Schwan <phil@clusterfs.com>
	*
	*/

	# define DEBUG_SUBSYSTEM S_LNET

	#include <linux/libcfs/libcfs.h>
	#include "tracefile.h"

	static char debug_file_name[1024];

	unsigned int libcfs_subsystem_debug = ~0;
	EXPORT_SYMBOL(libcfs_subsystem_debug);
	module_param(libcfs_subsystem_debug, int, 0644);
	MODULE_PARM_DESC(libcfs_subsystem_debug, "Lustre kernel debug subsystem mask");

	unsigned int libcfs_debug = (D_CANTMASK \|
	D_NETERROR \| D_HA \| D_CONFIG \| D_IOCTL);
	EXPORT_SYMBOL(libcfs_debug);
	module_param(libcfs_debug, int, 0644);
	MODULE_PARM_DESC(libcfs_debug, "Lustre kernel debug mask");

	static int libcfs_param_debug_mb_set(const char *val,
	const struct kernel_param *kp)
	{
	int rc;
	unsigned int num;

	rc = kstrtouint(val, 0, &num);
	if (rc < 0)
	return rc;

	if (!((unsigned int )kp->arg)) {
	((unsigned int )kp->arg) = num;
	return 0;
	}

	rc = cfs_trace_set_debug_mb(num);

	if (!rc)
	((unsigned int )kp->arg) = cfs_trace_get_debug_mb();

	return rc;
	}

	/* While debug_mb setting look like unsigned int, in fact
	* it needs quite a bunch of extra processing, so we define special
	* debugmb parameter type with corresponding methods to handle this case
	*/
	static const struct kernel_param_ops param_ops_debugmb = {
	.set = libcfs_param_debug_mb_set,
	.get = param_get_uint,
	};

	#define param_check_debugmb(name, p) \
	__param_check(name, p, unsigned int)

	static unsigned int libcfs_debug_mb;
	module_param(libcfs_debug_mb, debugmb, 0644);
	MODULE_PARM_DESC(libcfs_debug_mb, "Total debug buffer size.");

	unsigned int libcfs_printk = D_CANTMASK;
	module_param(libcfs_printk, uint, 0644);
	MODULE_PARM_DESC(libcfs_printk, "Lustre kernel debug console mask");

	unsigned int libcfs_console_ratelimit = 1;
	module_param(libcfs_console_ratelimit, uint, 0644);
	MODULE_PARM_DESC(libcfs_console_ratelimit, "Lustre kernel debug console ratelimit (0 to disable)");

	static int param_set_delay_minmax(const char *val,
	const struct kernel_param *kp,
	long min, long max)
	{
	long d;
	int sec;
	int rc;

	rc = kstrtoint(val, 0, &sec);
	if (rc)
	return -EINVAL;

	d = cfs_time_seconds(sec) / 100;
	if (d < min \|\| d > max)
	return -EINVAL;

	((unsigned int )kp->arg) = d;

	return 0;
	}

	static int param_get_delay(char buffer, const struct kernel_param kp)
	{
	unsigned int d = (unsigned int )kp->arg;

	return sprintf(buffer, "%u", (unsigned int)cfs_duration_sec(d * 100));
	}

	unsigned int libcfs_console_max_delay;
	unsigned int libcfs_console_min_delay;

	static int param_set_console_max_delay(const char *val,
	const struct kernel_param *kp)
	{
	return param_set_delay_minmax(val, kp,
	libcfs_console_min_delay, INT_MAX);
	}

	static const struct kernel_param_ops param_ops_console_max_delay = {
	.set = param_set_console_max_delay,
	.get = param_get_delay,
	};

	#define param_check_console_max_delay(name, p) \
	__param_check(name, p, unsigned int)

	module_param(libcfs_console_max_delay, console_max_delay, 0644);
	MODULE_PARM_DESC(libcfs_console_max_delay, "Lustre kernel debug console max delay (jiffies)");

	static int param_set_console_min_delay(const char *val,
	const struct kernel_param *kp)
	{
	return param_set_delay_minmax(val, kp,
	1, libcfs_console_max_delay);
	}

	static const struct kernel_param_ops param_ops_console_min_delay = {
	.set = param_set_console_min_delay,
	.get = param_get_delay,
	};

	#define param_check_console_min_delay(name, p) \
	__param_check(name, p, unsigned int)

	module_param(libcfs_console_min_delay, console_min_delay, 0644);
	MODULE_PARM_DESC(libcfs_console_min_delay, "Lustre kernel debug console min delay (jiffies)");

	static int param_set_uint_minmax(const char *val,
	const struct kernel_param *kp,
	unsigned int min, unsigned int max)
	{
	unsigned int num;
	int ret;

	if (!val)
	return -EINVAL;
	ret = kstrtouint(val, 0, &num);
	if (ret < 0 \|\| num < min \|\| num > max)
	return -EINVAL;
	((unsigned int )kp->arg) = num;
	return 0;
	}

	static int param_set_uintpos(const char val, const struct kernel_param kp)
	{
	return param_set_uint_minmax(val, kp, 1, -1);
	}

	static const struct kernel_param_ops param_ops_uintpos = {
	.set = param_set_uintpos,
	.get = param_get_uint,
	};

	#define param_check_uintpos(name, p) \
	__param_check(name, p, unsigned int)

	unsigned int libcfs_console_backoff = CDEBUG_DEFAULT_BACKOFF;
	module_param(libcfs_console_backoff, uintpos, 0644);
	MODULE_PARM_DESC(libcfs_console_backoff, "Lustre kernel debug console backoff factor");

	unsigned int libcfs_debug_binary = 1;

	unsigned int libcfs_stack = 3 * THREAD_SIZE / 4;
	EXPORT_SYMBOL(libcfs_stack);

	unsigned int libcfs_catastrophe;
	EXPORT_SYMBOL(libcfs_catastrophe);

	unsigned int libcfs_panic_on_lbug = 1;
	module_param(libcfs_panic_on_lbug, uint, 0644);
	MODULE_PARM_DESC(libcfs_panic_on_lbug, "Lustre kernel panic on LBUG");

	static wait_queue_head_t debug_ctlwq;

	char libcfs_debug_file_path_arr[PATH_MAX] = LIBCFS_DEBUG_FILE_PATH_DEFAULT;

	/* We need to pass a pointer here, but elsewhere this must be a const */
	static char *libcfs_debug_file_path;
	module_param(libcfs_debug_file_path, charp, 0644);
	MODULE_PARM_DESC(libcfs_debug_file_path,
	"Path for dumping debug logs, set 'NONE' to prevent log dumping");

	int libcfs_panic_in_progress;

	/* libcfs_debug_token2mask() expects the returned string in lower-case */
	static const char *
	libcfs_debug_subsys2str(int subsys)
	{
	static const char * const libcfs_debug_subsystems[] =
	LIBCFS_DEBUG_SUBSYS_NAMES;

	if (subsys >= ARRAY_SIZE(libcfs_debug_subsystems))
	return NULL;

	return libcfs_debug_subsystems[subsys];
	}

	/* libcfs_debug_token2mask() expects the returned string in lower-case */
	static const char *
	libcfs_debug_dbg2str(int debug)
	{
	static const char * const libcfs_debug_masks[] =
	LIBCFS_DEBUG_MASKS_NAMES;

	if (debug >= ARRAY_SIZE(libcfs_debug_masks))
	return NULL;

	return libcfs_debug_masks[debug];
	}

	int
	libcfs_debug_mask2str(char *str, int size, int mask, int is_subsys)
	{
	const char (fn)(int bit) = is_subsys ? libcfs_debug_subsys2str :
	libcfs_debug_dbg2str;
	int len = 0;
	const char *token;
	int i;

	if (!mask) { /* "0" */
	if (size > 0)
	str[0] = '0';
	len = 1;
	} else { /* space-separated tokens */
	for (i = 0; i < 32; i++) {
	if (!(mask & (1 << i)))
	continue;

	token = fn(i);
	if (!token) /* unused bit */
	continue;

	if (len > 0) { /* separator? */
	if (len < size)
	str[len] = ' ';
	len++;
	}

	while (*token) {
	if (len < size)
	str[len] = *token;
	token++;
	len++;
	}
	}
	}

	/* terminate 'str' */
	if (len < size)
	str[len] = 0;
	else
	str[size - 1] = 0;

	return len;
	}

	int
	libcfs_debug_str2mask(int mask, const char str, int is_subsys)
	{
	const char (fn)(int bit) = is_subsys ? libcfs_debug_subsys2str :
	libcfs_debug_dbg2str;
	int m = 0;
	int matched;
	int n;
	int t;

	/* Allow a number for backwards compatibility */

	for (n = strlen(str); n > 0; n--)
	if (!isspace(str[n - 1]))
	break;
	matched = n;
	t = sscanf(str, "%i%n", &m, &matched);
	if (t >= 1 && matched == n) {
	/* don't print warning for lctl set_param debug=0 or -1 */
	if (m && m != -1)
	CWARN("You are trying to use a numerical value for the mask - this will be deprecated in a future release.\n");
	*mask = m;
	return 0;
	}

	return cfs_str2mask(str, fn, mask, is_subsys ? 0 : D_CANTMASK,
	0xffffffff);
	}

	/**
	* Dump Lustre log to ::debug_file_path by calling tracefile_dump_all_pages()
	*/
	void libcfs_debug_dumplog_internal(void *arg)
	{
	static time64_t last_dump_time;
	time64_t current_time;
	void *journal_info;

	journal_info = current->journal_info;
	current->journal_info = NULL;
	current_time = ktime_get_real_seconds();

	if (strncmp(libcfs_debug_file_path_arr, "NONE", 4) &&
	current_time > last_dump_time) {
	last_dump_time = current_time;
	snprintf(debug_file_name, sizeof(debug_file_name) - 1,
	"%s.%lld.%ld", libcfs_debug_file_path_arr,
	(s64)current_time, (long)arg);
	pr_alert("LustreError: dumping log to %s\n", debug_file_name);
	cfs_tracefile_dump_all_pages(debug_file_name);
	libcfs_run_debug_log_upcall(debug_file_name);
	}

	current->journal_info = journal_info;
	}

	static int libcfs_debug_dumplog_thread(void *arg)
	{
	libcfs_debug_dumplog_internal(arg);
	wake_up(&debug_ctlwq);
	return 0;
	}

	void libcfs_debug_dumplog(void)
	{
	wait_queue_entry_t wait;
	struct task_struct *dumper;

	/* we're being careful to ensure that the kernel thread is
	* able to set our state to running as it exits before we
	* get to schedule()
	*/
	init_waitqueue_entry(&wait, current);
	add_wait_queue(&debug_ctlwq, &wait);

	dumper = kthread_run(libcfs_debug_dumplog_thread,
	(void *)(long)current_pid(),
	"libcfs_debug_dumper");
	set_current_state(TASK_INTERRUPTIBLE);
	if (IS_ERR(dumper))
	pr_err("LustreError: cannot start log dump thread: %ld\n",
	PTR_ERR(dumper));
	else
	schedule();

	/* be sure to teardown if cfs_create_thread() failed */
	remove_wait_queue(&debug_ctlwq, &wait);
	set_current_state(TASK_RUNNING);
	}
	EXPORT_SYMBOL(libcfs_debug_dumplog);

	int libcfs_debug_init(unsigned long bufsize)
	{
	unsigned int max = libcfs_debug_mb;
	int rc = 0;

	init_waitqueue_head(&debug_ctlwq);

	if (libcfs_console_max_delay <= 0 \|\| /* not set by user or */
	libcfs_console_min_delay <= 0 \|\| /* set to invalid values */
	libcfs_console_min_delay >= libcfs_console_max_delay) {
	libcfs_console_max_delay = CDEBUG_DEFAULT_MAX_DELAY;
	libcfs_console_min_delay = CDEBUG_DEFAULT_MIN_DELAY;
	}

	if (libcfs_debug_file_path) {
	strlcpy(libcfs_debug_file_path_arr,
	libcfs_debug_file_path,
	sizeof(libcfs_debug_file_path_arr));
	}

	/* If libcfs_debug_mb is set to an invalid value or uninitialized
	* then just make the total buffers smp_num_cpus * TCD_MAX_PAGES
	*/
	if (max > cfs_trace_max_debug_mb() \|\| max < num_possible_cpus()) {
	max = TCD_MAX_PAGES;
	} else {
	max = max / num_possible_cpus();
	max <<= (20 - PAGE_SHIFT);
	}

	rc = cfs_tracefile_init(max);
	if (!rc) {
	libcfs_register_panic_notifier();
	libcfs_debug_mb = cfs_trace_get_debug_mb();
	}

	return rc;
	}

	int libcfs_debug_cleanup(void)
	{
	libcfs_unregister_panic_notifier();
	cfs_tracefile_exit();
	return 0;
	}

	int libcfs_debug_clear_buffer(void)
	{
	cfs_trace_flush_pages();
	return 0;
	}

	/* Debug markers, although printed by S_LNET should not be be marked as such. */
	#undef DEBUG_SUBSYSTEM
	#define DEBUG_SUBSYSTEM S_UNDEFINED
	int libcfs_debug_mark_buffer(const char *text)
	{
	CDEBUG(D_TRACE,
	"***************************************************\n");
	LCONSOLE(D_WARNING, "DEBUG MARKER: %s\n", text);
	CDEBUG(D_TRACE,
	"***************************************************\n");

	return 0;
	}

	#undef DEBUG_SUBSYSTEM
	#define DEBUG_SUBSYSTEM S_LNET