Skip to main content

Browse the archive

Revision 7bf811a595a895b7a886dcf218d0d34f97df76dc authored by Josef Bacik on 08 October 2013, 02:11:09 UTC, committed by Chris Mason on 11 October 2013, 01:27:56 UTC 
Btrfs: limit delalloc pages outside of find_delalloc_range
 
Liu fixed part of this problem and unfortunately I steered him in slightly the
wrong direction and so didn't completely fix the problem.  The problem is we
limit the size of the delalloc range we are looking for to max bytes and then we
try to lock that range.  If we fail to lock the pages in that range we will
shrink the max bytes to a single page and re loop.  However if our first page is
inside of the delalloc range then we will end up limiting the end of the range
to a period before our first page.  This is illustrated below

[0 -------- delalloc range --------- 256mb]
                                  [page]

So find_delalloc_range will return with delalloc_start as 0 and end as 128mb,
and then we will notice that delalloc_start < *start and adjust it up, but not
adjust delalloc_end up, so things go sideways.  To fix this we need to not limit
the max bytes in find_delalloc_range, but in find_lock_delalloc_range and that
way we don't end up with this confusion.  Thanks,

Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
1 parent 4871c15
Raw File
opp.h 
/*
 * Generic OPP Interface
 *
 * Copyright (C) 2009-2010 Texas Instruments Incorporated.
 *	Nishanth Menon
 *	Romit Dasgupta
 *	Kevin Hilman
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 */

#ifndef __LINUX_OPP_H__
#define __LINUX_OPP_H__

#include <linux/err.h>
#include <linux/cpufreq.h>
#include <linux/notifier.h>

struct opp;
struct device;

enum opp_event {
	OPP_EVENT_ADD, OPP_EVENT_ENABLE, OPP_EVENT_DISABLE,
};

#if defined(CONFIG_PM_OPP)

unsigned long opp_get_voltage(struct opp *opp);

unsigned long opp_get_freq(struct opp *opp);

int opp_get_opp_count(struct device *dev);

struct opp *opp_find_freq_exact(struct device *dev, unsigned long freq,
				bool available);

struct opp *opp_find_freq_floor(struct device *dev, unsigned long *freq);

struct opp *opp_find_freq_ceil(struct device *dev, unsigned long *freq);

int opp_add(struct device *dev, unsigned long freq, unsigned long u_volt);

int opp_enable(struct device *dev, unsigned long freq);

int opp_disable(struct device *dev, unsigned long freq);

struct srcu_notifier_head *opp_get_notifier(struct device *dev);
#else
static inline unsigned long opp_get_voltage(struct opp *opp)
{
	return 0;
}

static inline unsigned long opp_get_freq(struct opp *opp)
{
	return 0;
}

static inline int opp_get_opp_count(struct device *dev)
{
	return 0;
}

static inline struct opp *opp_find_freq_exact(struct device *dev,
					unsigned long freq, bool available)
{
	return ERR_PTR(-EINVAL);
}

static inline struct opp *opp_find_freq_floor(struct device *dev,
					unsigned long *freq)
{
	return ERR_PTR(-EINVAL);
}

static inline struct opp *opp_find_freq_ceil(struct device *dev,
					unsigned long *freq)
{
	return ERR_PTR(-EINVAL);
}

static inline int opp_add(struct device *dev, unsigned long freq,
					unsigned long u_volt)
{
	return -EINVAL;
}

static inline int opp_enable(struct device *dev, unsigned long freq)
{
	return 0;
}

static inline int opp_disable(struct device *dev, unsigned long freq)
{
	return 0;
}

static inline struct srcu_notifier_head *opp_get_notifier(struct device *dev)
{
	return ERR_PTR(-EINVAL);
}
#endif		/* CONFIG_PM_OPP */

#if defined(CONFIG_PM_OPP) && defined(CONFIG_OF)
int of_init_opp_table(struct device *dev);
#else
static inline int of_init_opp_table(struct device *dev)
{
	return -EINVAL;
}
#endif

#if defined(CONFIG_CPU_FREQ) && defined(CONFIG_PM_OPP)
int opp_init_cpufreq_table(struct device *dev,
			    struct cpufreq_frequency_table **table);
void opp_free_cpufreq_table(struct device *dev,
				struct cpufreq_frequency_table **table);
#else
static inline int opp_init_cpufreq_table(struct device *dev,
			    struct cpufreq_frequency_table **table)
{
	return -EINVAL;
}

static inline
void opp_free_cpufreq_table(struct device *dev,
				struct cpufreq_frequency_table **table)
{
}
#endif		/* CONFIG_CPU_FREQ */

#endif		/* __LINUX_OPP_H__ */
back to top