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authorRafael J. Wysocki <rjw@sisk.pl>2010-09-22 16:09:10 -0400
committerRafael J. Wysocki <rjw@sisk.pl>2010-10-16 19:57:43 -0400
commit074037ec79bea73edf1b1ec72fef1010e83e3cc5 (patch)
tree1876caa07f755e680da5ea102d985efe4b508d56 /drivers/base/power/main.c
parent0702d9ee0f1dcb6258789032f03b3208bfafaffc (diff)
PM / Wakeup: Introduce wakeup source objects and event statistics (v3)
Introduce struct wakeup_source for representing system wakeup sources within the kernel and for collecting statistics related to them. Make the recently introduced helper functions pm_wakeup_event(), pm_stay_awake() and pm_relax() use struct wakeup_source objects internally, so that wakeup statistics associated with wakeup devices can be collected and reported in a consistent way (the definition of pm_relax() is changed, which is harmless, because this function is not called directly by anyone yet). Introduce new wakeup-related sysfs device attributes in /sys/devices/.../power for reporting the device wakeup statistics. Change the global wakeup events counters event_count and events_in_progress into atomic variables, so that it is not necessary to acquire a global spinlock in pm_wakeup_event(), pm_stay_awake() and pm_relax(), which should allow us to avoid lock contention in these functions on SMP systems with many wakeup devices. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
Diffstat (limited to 'drivers/base/power/main.c')
-rw-r--r--drivers/base/power/main.c4
1 files changed, 3 insertions, 1 deletions
diff --git a/drivers/base/power/main.c b/drivers/base/power/main.c
index db677199403c..7ae6fe414c38 100644
--- a/drivers/base/power/main.c
+++ b/drivers/base/power/main.c
@@ -60,7 +60,8 @@ void device_pm_init(struct device *dev)
60 dev->power.status = DPM_ON; 60 dev->power.status = DPM_ON;
61 init_completion(&dev->power.completion); 61 init_completion(&dev->power.completion);
62 complete_all(&dev->power.completion); 62 complete_all(&dev->power.completion);
63 dev->power.wakeup_count = 0; 63 dev->power.wakeup = NULL;
64 spin_lock_init(&dev->power.lock);
64 pm_runtime_init(dev); 65 pm_runtime_init(dev);
65} 66}
66 67
@@ -120,6 +121,7 @@ void device_pm_remove(struct device *dev)
120 mutex_lock(&dpm_list_mtx); 121 mutex_lock(&dpm_list_mtx);
121 list_del_init(&dev->power.entry); 122 list_del_init(&dev->power.entry);
122 mutex_unlock(&dpm_list_mtx); 123 mutex_unlock(&dpm_list_mtx);
124 device_wakeup_disable(dev);
123 pm_runtime_remove(dev); 125 pm_runtime_remove(dev);
124} 126}
125 127
generated by cgit v1.2.2 (git 2.25.0) at 2025-09-16 18:00:46 -0400
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/*
 * A generic kernel FIFO implementation
 *
 * Copyright (C) 2009/2010 Stefani Seibold <stefani@seibold.net>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * 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 for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 *
 */

#ifndef _LINUX_KFIFO_H
#define _LINUX_KFIFO_H

/*
 * How to porting drivers to the new generic FIFO API:
 *
 * - Modify the declaration of the "struct kfifo *" object into a
 *   in-place "struct kfifo" object
 * - Init the in-place object with kfifo_alloc() or kfifo_init()
 *   Note: The address of the in-place "struct kfifo" object must be
 *   passed as the first argument to this functions
 * - Replace the use of __kfifo_put into kfifo_in and __kfifo_get
 *   into kfifo_out
 * - Replace the use of kfifo_put into kfifo_in_spinlocked and kfifo_get
 *   into kfifo_out_spinlocked
 *   Note: the spinlock pointer formerly passed to kfifo_init/kfifo_alloc
 *   must be passed now to the kfifo_in_spinlocked and kfifo_out_spinlocked
 *   as the last parameter
 * - The formerly __kfifo_* functions are renamed into kfifo_*
 */

/*
 * Note about locking : There is no locking required until only * one reader
 * and one writer is using the fifo and no kfifo_reset() will be * called
 *  kfifo_reset_out() can be safely used, until it will be only called
 * in the reader thread.
 *  For multiple writer and one reader there is only a need to lock the writer.
 * And vice versa for only one writer and multiple reader there is only a need
 * to lock the reader.
 */

#include <linux/kernel.h>
#include <linux/spinlock.h>
#include <linux/stddef.h>
#include <linux/scatterlist.h>

struct __kfifo {
	unsigned int	in;
	unsigned int	out;
	unsigned int	mask;
	unsigned int	esize;
	void		*data;
};

#define __STRUCT_KFIFO_COMMON(datatype, recsize, ptrtype) \
	union { \
		struct __kfifo	kfifo; \
		datatype	*type; \
		char		(*rectype)[recsize]; \
		ptrtype		*ptr; \
		const ptrtype	*ptr_const; \
	}

#define __STRUCT_KFIFO(type, size, recsize, ptrtype) \
{ \
	__STRUCT_KFIFO_COMMON(type, recsize, ptrtype); \
	type		buf[((size < 2) || (size & (size - 1))) ? -1 : size]; \
}

#define STRUCT_KFIFO(type, size) \
	struct __STRUCT_KFIFO(type, size, 0, type)

#define __STRUCT_KFIFO_PTR(type, recsize, ptrtype) \
{ \
	__STRUCT_KFIFO_COMMON(type, recsize, ptrtype); \
	type		buf[0]; \
}

#define STRUCT_KFIFO_PTR(type) \
	struct __STRUCT_KFIFO_PTR(type, 0, type)

/*
 * define compatibility "struct kfifo" for dynamic allocated fifos
 */
struct kfifo __STRUCT_KFIFO_PTR(unsigned char, 0, void);

#define STRUCT_KFIFO_REC_1(size) \
	struct __STRUCT_KFIFO(unsigned char, size, 1, void)

#define STRUCT_KFIFO_REC_2(size) \
	struct __STRUCT_KFIFO(unsigned char, size, 2, void)

/*
 * define kfifo_rec types
 */
struct kfifo_rec_ptr_1 __STRUCT_KFIFO_PTR(unsigned char, 1, void);
struct kfifo_rec_ptr_2 __STRUCT_KFIFO_PTR(unsigned char, 2, void);

/*
 * helper macro to distinguish between real in place fifo where the fifo
 * array is a part of the structure and the fifo type where the array is
 * outside of the fifo structure.
 */
#define	__is_kfifo_ptr(fifo)	(sizeof(*fifo) == sizeof(struct __kfifo))

/**
 * DECLARE_KFIFO_PTR - macro to declare a fifo pointer object
 * @fifo: name of the declared fifo
 * @type: type of the fifo elements
 */
#define DECLARE_KFIFO_PTR(fifo, type)	STRUCT_KFIFO_PTR(type) fifo

/**
 * DECLARE_KFIFO - macro to declare a fifo object
 * @fifo: name of the declared fifo
 * @type: type of the fifo elements
 * @size: the number of elements in the fifo, this must be a power of 2
 */
#define DECLARE_KFIFO(fifo, type, size)	STRUCT_KFIFO(type, size) fifo

/**
 * INIT_KFIFO - Initialize a fifo declared by DECLARE_KFIFO
 * @fifo: name of the declared fifo datatype
 */
#define INIT_KFIFO(fifo) \
(void)({ \
	typeof(&(fifo)) __tmp = &(fifo); \
	struct __kfifo *__kfifo = &__tmp->kfifo; \
	__kfifo->in = 0; \
	__kfifo->out = 0; \
	__kfifo->mask = __is_kfifo_ptr(__tmp) ? 0 : ARRAY_SIZE(__tmp->buf) - 1;\
	__kfifo->esize = sizeof(*__tmp->buf); \
	__kfifo->data = __is_kfifo_ptr(__tmp) ?  NULL : __tmp->buf; \
})

/**
 * DEFINE_KFIFO - macro to define and initialize a fifo
 * @fifo: name of the declared fifo datatype
 * @type: type of the fifo elements
 * @size: the number of elements in the fifo, this must be a power of 2
 *
 * Note: the macro can be used for global and local fifo data type variables.
 */
#define DEFINE_KFIFO(fifo, type, size) \
	DECLARE_KFIFO(fifo, type, size) = \
	(typeof(fifo)) { \
		{ \
			{ \
			.in	= 0, \
			.out	= 0, \
			.mask	= __is_kfifo_ptr(&(fifo)) ? \
				  0 : \
				  ARRAY_SIZE((fifo).buf) - 1, \
			.esize	= sizeof(*(fifo).buf), \
			.data	= __is_kfifo_ptr(&(fifo)) ? \
				NULL : \
				(fifo).buf, \
			} \
		} \
	}


static inline unsigned int __must_check
__kfifo_uint_must_check_helper(unsigned int val)
{
	return val;
}

static inline int __must_check
__kfifo_int_must_check_helper(int val)
{
	return val;
}

/**
 * kfifo_initialized - Check if the fifo is initialized
 * @fifo: address of the fifo to check
 *
 * Return %true if fifo is initialized, otherwise %false.
 * Assumes the fifo was 0 before.
 */
#define kfifo_initialized(fifo) ((fifo)->kfifo.mask)

/**
 * kfifo_esize - returns the size of the element managed by the fifo
 * @fifo: address of the fifo to be used
 */
#define kfifo_esize(fifo)	((fifo)->kfifo.esize)

/**
 * kfifo_recsize - returns the size of the record length field
 * @fifo: address of the fifo to be used
 */
#define kfifo_recsize(fifo)	(sizeof(*(fifo)->rectype))

/**
 * kfifo_size - returns the size of the fifo in elements
 * @fifo: address of the fifo to be used
 */
#define kfifo_size(fifo)	((fifo)->kfifo.mask + 1)

/**
 * kfifo_reset - removes the entire fifo content
 * @fifo: address of the fifo to be used
 *
 * Note: usage of kfifo_reset() is dangerous. It should be only called when the
 * fifo is exclusived locked or when it is secured that no other thread is
 * accessing the fifo.
 */
#define kfifo_reset(fifo) \
(void)({ \
	typeof((fifo) + 1) __tmp = (fifo); \
	__tmp->kfifo.in = __tmp->kfifo.out = 0; \
})

/**
 * kfifo_reset_out - skip fifo content
 * @fifo: address of the fifo to be used
 *
 * Note: The usage of kfifo_reset_out() is safe until it will be only called
 * from the reader thread and there is only one concurrent reader. Otherwise
 * it is dangerous and must be handled in the same way as kfifo_reset().
 */
#define kfifo_reset_out(fifo)	\
(void)({ \
	typeof((fifo) + 1) __tmp = (fifo); \
	__tmp->kfifo.out = __tmp->kfifo.in; \
})

/**
 * kfifo_len - returns the number of used elements in the fifo
 * @fifo: address of the fifo to be used
 */
#define kfifo_len(fifo) \
({ \
	typeof((fifo) + 1) __tmpl = (fifo); \
	__tmpl->kfifo.in - __tmpl->kfifo.out; \
})

/**
 * kfifo_is_empty - returns true if the fifo is empty
 * @fifo: address of the fifo to be used
 */
#define	kfifo_is_empty(fifo) \
({ \
	typeof((fifo) + 1) __tmpq = (fifo); \
	__tmpq->kfifo.in == __tmpq->kfifo.out; \
})

/**
 * kfifo_is_full - returns true if the fifo is full
 * @fifo: address of the fifo to be used
 */
#define	kfifo_is_full(fifo) \
({ \
	typeof((fifo) + 1) __tmpq = (fifo); \
	kfifo_len(__tmpq) > __tmpq->kfifo.mask; \
})

/**
 * kfifo_avail - returns the number of unused elements in the fifo
 * @fifo: address of the fifo to be used
 */
#define	kfifo_avail(fifo) \
__kfifo_uint_must_check_helper( \
({ \
	typeof((fifo) + 1) __tmpq = (fifo); \
	const size_t __recsize = sizeof(*__tmpq->rectype); \
	unsigned int __avail = kfifo_size(__tmpq) - kfifo_len(__tmpq); \
	(__recsize) ? ((__avail <= __recsize) ? 0 : \
	__kfifo_max_r(__avail - __recsize, __recsize)) : \
	__avail; \
}) \
)

/**
 * kfifo_skip - skip output data
 * @fifo: address of the fifo to be used
 */
#define	kfifo_skip(fifo) \
(void)({ \
	typeof((fifo) + 1) __tmp = (fifo); \
	const size_t __recsize = sizeof(*__tmp->rectype); \
	struct __kfifo *__kfifo = &__tmp->kfifo; \
	if (__recsize) \
		__kfifo_skip_r(__kfifo, __recsize); \
	else \
		__kfifo->out++; \
})

/**
 * kfifo_peek_len - gets the size of the next fifo record
 * @fifo: address of the fifo to be used
 *
 * This function returns the size of the next fifo record in number of bytes.
 */
#define kfifo_peek_len(fifo) \
__kfifo_uint_must_check_helper( \
({ \
	typeof((fifo) + 1) __tmp = (fifo); \
	const size_t __recsize = sizeof(*__tmp->rectype); \
	struct __kfifo *__kfifo = &__tmp->kfifo; \
	(!__recsize) ? kfifo_len(__tmp) * sizeof(*__tmp->type) : \
	__kfifo_len_r(__kfifo, __recsize); \
}) \
)

/**
 * kfifo_alloc - dynamically allocates a new fifo buffer
 * @fifo: pointer to the fifo
 * @size: the number of elements in the fifo, this must be a power of 2
 * @gfp_mask: get_free_pages mask, passed to kmalloc()
 *
 * This macro dynamically allocates a new fifo buffer.
 *
 * The numer of elements will be rounded-up to a power of 2.
 * The fifo will be release with kfifo_free().
 * Return 0 if no error, otherwise an error code.
 */
#define kfifo_alloc(fifo, size, gfp_mask) \
__kfifo_int_must_check_helper( \
({ \
	typeof((fifo) + 1) __tmp = (fifo); \
	struct __kfifo *__kfifo = &__tmp->kfifo; \
	__is_kfifo_ptr(__tmp) ? \
	__kfifo_alloc(__kfifo, size, sizeof(*__tmp->type), gfp_mask) : \
	-EINVAL; \
}) \
)

/**
 * kfifo_free - frees the fifo
 * @fifo: the fifo to be freed
 */
#define kfifo_free(fifo) \
({ \
	typeof((fifo) + 1) __tmp = (fifo); \
	struct __kfifo *__kfifo = &__tmp->kfifo; \
	if (__is_kfifo_ptr(__tmp)) \
		__kfifo_free(__kfifo); \
})

/**
 * kfifo_init - initialize a fifo using a preallocated buffer
 * @fifo: the fifo to assign the buffer
 * @buffer: the preallocated buffer to be used