rockbox/firmware/kernel/thread-internal.h
Michael Sevakis 5b08f1a5b9 Remove I/O priority. It is harmful when used with the new file code.
HAVE_IO_PRIORITY was defined for native targets with dircache.

It is already effectively disabled for the most part since dircache no
longer lowers its thread's I/O priority. It existed primarily for the
aforementioned configuration.

Change-Id: Ia04935305397ba14df34647c8ea29c2acaea92aa
2014-08-30 14:01:21 -04:00

422 lines
14 KiB
C

/***************************************************************************
* __________ __ ___.
* Open \______ \ ____ ____ | | _\_ |__ _______ ___
* Source | _// _ \_/ ___\| |/ /| __ \ / _ \ \/ /
* Jukebox | | ( <_> ) \___| < | \_\ ( <_> > < <
* Firmware |____|_ /\____/ \___ >__|_ \|___ /\____/__/\_ \
* \/ \/ \/ \/ \/
* $Id$
*
* Copyright (C) 2002 by Ulf Ralberg
*
* 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 software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
* KIND, either express or implied.
*
****************************************************************************/
#ifndef THREAD_INTERNAL_H
#define THREAD_INTERNAL_H
#include "thread.h"
#include <stdio.h>
#include "panic.h"
#include "debug.h"
/*
* We need more stack when we run under a host
* maybe more expensive C lib functions?
*
* simulator (possibly) doesn't simulate stack usage anyway but well ... */
#if defined(HAVE_SDL_THREADS) || defined(__PCTOOL__)
struct regs
{
void *t; /* OS thread */
void *told; /* Last thread in slot (explained in thead-sdl.c) */
void *s; /* Semaphore for blocking and wakeup */
void (*start)(void); /* Start function */
};
#define DEFAULT_STACK_SIZE 0x100 /* tiny, ignored anyway */
#else
#include "asm/thread.h"
#endif /* HAVE_SDL_THREADS */
/* NOTE: The use of the word "queue" may also refer to a linked list of
threads being maintained that are normally dealt with in FIFO order
and not necessarily kernel event_queue */
enum
{
/* States without a timeout must be first */
STATE_KILLED = 0, /* Thread is killed (default) */
STATE_RUNNING, /* Thread is currently running */
STATE_BLOCKED, /* Thread is indefinitely blocked on a queue */
/* These states involve adding the thread to the tmo list */
STATE_SLEEPING, /* Thread is sleeping with a timeout */
STATE_BLOCKED_W_TMO, /* Thread is blocked on a queue with a timeout */
/* Miscellaneous states */
STATE_FROZEN, /* Thread is suspended and will not run until
thread_thaw is called with its ID */
THREAD_NUM_STATES,
TIMEOUT_STATE_FIRST = STATE_SLEEPING,
};
#ifdef HAVE_PRIORITY_SCHEDULING
/* Quick-disinherit of priority elevation. Must be a running thread. */
void priority_disinherit(struct thread_entry *thread, struct blocker *bl);
struct priority_distribution
{
uint8_t hist[NUM_PRIORITIES]; /* Histogram: Frequency for each priority */
priobit_t mask; /* Bitmask of hist entries that are not zero */
};
#endif /* HAVE_PRIORITY_SCHEDULING */
#define __rtr_queue lldc_head
#define __rtr_queue_node lldc_node
#define __tmo_queue ll_head
#define __tmo_queue_node ll_node
/* Information kept in each thread slot
* members are arranged according to size - largest first - in order
* to ensure both alignment and packing at the same time.
*/
struct thread_entry
{
struct regs context; /* Register context at switch -
_must_ be first member */
#ifndef HAVE_SDL_THREADS
uintptr_t *stack; /* Pointer to top of stack */
#endif
const char *name; /* Thread name */
long tmo_tick; /* Tick when thread should be woken */
struct __rtr_queue_node rtr; /* Node for run queue */
struct __tmo_queue_node tmo; /* Links for timeout list */
struct __wait_queue_node wq; /* Node for wait queue */
struct __wait_queue *volatile wqp; /* Pointer to registered wait queue */
#if NUM_CORES > 1
struct corelock waiter_cl; /* Corelock for thread_wait */
struct corelock slot_cl; /* Corelock to lock thread slot */
unsigned char core; /* The core to which thread belongs */
#endif
struct __wait_queue queue; /* List of threads waiting for thread to be
removed */
volatile intptr_t retval; /* Return value from a blocked operation/
misc. use */
uint32_t id; /* Current slot id */
int __errno; /* Thread error number (errno tls) */
#ifdef HAVE_PRIORITY_SCHEDULING
/* Priority summary of owned objects that support inheritance */
struct blocker *blocker; /* Pointer to blocker when this thread is blocked
on an object that supports PIP -
states: STATE_BLOCKED/STATE_BLOCKED_W_TMO */
struct priority_distribution pdist; /* Priority summary of owned objects
that have blocked threads and thread's own
base priority */
int skip_count; /* Number of times skipped if higher priority
thread was running */
unsigned char base_priority; /* Base priority (set explicitly during
creation or thread_set_priority) */
unsigned char priority; /* Scheduled priority (higher of base or
all threads blocked by this one) */
#endif
#ifndef HAVE_SDL_THREADS
unsigned short stack_size; /* Size of stack in bytes */
#endif
unsigned char state; /* Thread slot state (STATE_*) */
#ifdef HAVE_SCHEDULER_BOOSTCTRL
unsigned char cpu_boost; /* CPU frequency boost flag */
#endif
};
/* Thread ID, 32 bits = |VVVVVVVV|VVVVVVVV|VVVVVVVV|SSSSSSSS| */
#define THREAD_ID_VERSION_SHIFT 8
#define THREAD_ID_VERSION_MASK 0xffffff00
#define THREAD_ID_SLOT_MASK 0x000000ff
#define THREAD_ID_INIT(n) ((1u << THREAD_ID_VERSION_SHIFT) | (n))
#define THREAD_ID_SLOT(id) ((id) & THREAD_ID_SLOT_MASK)
#define DEADBEEF ((uintptr_t)0xdeadbeefdeadbeefull)
/* Information kept for each core
* Members are arranged for the same reason as in thread_entry
*/
struct core_entry
{
/* "Active" lists - core is constantly active on these and are never
locked and interrupts do not access them */
struct __rtr_queue rtr; /* Threads that are runnable */
struct __tmo_queue tmo; /* Threads on a bounded wait */
struct thread_entry *running; /* Currently running thread */
#ifdef HAVE_PRIORITY_SCHEDULING
struct priority_distribution rtr_dist; /* Summary of runnables */
#endif
long next_tmo_check; /* Next due timeout check */
#if NUM_CORES > 1
struct corelock rtr_cl; /* Lock for rtr list */
#endif /* NUM_CORES */
};
/* Hide a few scheduler details from itself to make allocation more flexible */
#define __main_thread_name \
({ extern const char __main_thread_name_str[]; \
__main_thread_name_str; })
static FORCE_INLINE
void * __get_main_stack(size_t *stacksize)
{
#if (CONFIG_PLATFORM & PLATFORM_NATIVE)
extern uintptr_t stackbegin[];
extern uintptr_t stackend[];
#else
extern uintptr_t *stackbegin;
extern uintptr_t *stackend;
#endif
*stacksize = (uintptr_t)stackend - (uintptr_t)stackbegin;
return stackbegin;
}
void format_thread_name(char *buf, size_t bufsize,
const struct thread_entry *thread);
static FORCE_INLINE
struct core_entry * __core_id_entry(unsigned int core)
{
#if NUM_CORES > 1
extern struct core_entry * __cores[NUM_CORES];
return __cores[core];
#else
extern struct core_entry __cores[NUM_CORES];
return &__cores[core];
#endif
}
#define __running_self_entry() \
__core_id_entry(CURRENT_CORE)->running
static FORCE_INLINE
struct thread_entry * __thread_slot_entry(unsigned int slotnum)
{
extern struct thread_entry * __threads[MAXTHREADS];
return __threads[slotnum];
}
#define __thread_id_entry(id) \
__thread_slot_entry(THREAD_ID_SLOT(id))
#define THREAD_FROM(p, member) \
container_of(p, struct thread_entry, member)
#define RTR_EMPTY(rtrp) \
({ (rtrp)->head == NULL; })
#define RTR_THREAD_FIRST(rtrp) \
({ THREAD_FROM((rtrp)->head, rtr); })
#define RTR_THREAD_NEXT(thread) \
({ THREAD_FROM((thread)->rtr.next, rtr); })
#define TMO_THREAD_FIRST(tmop) \
({ struct __tmo_queue *__tmop = (tmop); \
__tmop->head ? THREAD_FROM(__tmop->head, tmo) : NULL; })
#define TMO_THREAD_NEXT(thread) \
({ struct __tmo_queue_node *__next = (thread)->tmo.next; \
__next ? THREAD_FROM(__next, tmo) : NULL; })
#define WQ_THREAD_FIRST(wqp) \
({ struct __wait_queue *__wqp = (wqp); \
__wqp->head ? THREAD_FROM(__wqp->head, wq) : NULL; })
#define WQ_THREAD_NEXT(thread) \
({ struct __wait_queue_node *__next = (thread)->wq.next; \
__next ? THREAD_FROM(__next, wq) : NULL; })
void thread_alloc_init(void) INIT_ATTR;
struct thread_entry * thread_alloc(void);
void thread_free(struct thread_entry *thread);
void new_thread_id(struct thread_entry *thread);
/* Switch to next runnable thread */
void switch_thread(void);
/* Blocks a thread for at least the specified number of ticks (0 = wait until
* next tick) */
void sleep_thread(int ticks);
/* Blocks the current thread on a thread queue (< 0 == infinite) */
void block_thread_(struct thread_entry *current, int timeout);
#ifdef HAVE_PRIORITY_SCHEDULING
#define block_thread(thread, timeout, __wqp, bl) \
({ struct thread_entry *__t = (thread); \
__t->wqp = (__wqp); \
if (!__builtin_constant_p(bl) || (bl)) \
__t->blocker = (bl); \
block_thread_(__t, (timeout)); })
#else
#define block_thread(thread, timeout, __wqp, bl...) \
({ struct thread_entry *__t = (thread); \
__t->wqp = (__wqp); \
block_thread_(__t, (timeout)); })
#endif
/* Return bit flags for thread wakeup */
#define THREAD_NONE 0x0 /* No thread woken up (exclusive) */
#define THREAD_OK 0x1 /* A thread was woken up */
#define THREAD_SWITCH 0x2 /* Task switch recommended (one or more of
higher priority than current were woken) */
/* A convenience function for waking an entire queue of threads. */
unsigned int wait_queue_wake(struct __wait_queue *wqp);
/* Wakeup a thread at the head of a list */
enum wakeup_thread_protocol
{
WAKEUP_DEFAULT,
WAKEUP_TRANSFER,
WAKEUP_RELEASE,
WAKEUP_TRANSFER_MULTI,
};
unsigned int wakeup_thread_(struct thread_entry *thread
IF_PRIO(, enum wakeup_thread_protocol proto));
#ifdef HAVE_PRIORITY_SCHEDULING
#define wakeup_thread(thread, proto) \
wakeup_thread_((thread), (proto))
#else
#define wakeup_thread(thread, proto...) \
wakeup_thread_((thread));
#endif
#ifdef RB_PROFILE
void profile_thread(void);
#endif
static inline void rtr_queue_init(struct __rtr_queue *rtrp)
{
lldc_init(rtrp);
}
static inline void rtr_queue_make_first(struct __rtr_queue *rtrp,
struct thread_entry *thread)
{
rtrp->head = &thread->rtr;
}
static inline void rtr_queue_add(struct __rtr_queue *rtrp,
struct thread_entry *thread)
{
lldc_insert_last(rtrp, &thread->rtr);
}
static inline void rtr_queue_remove(struct __rtr_queue *rtrp,
struct thread_entry *thread)
{
lldc_remove(rtrp, &thread->rtr);
}
#define TMO_NOT_QUEUED (NULL + 1)
static inline bool tmo_is_queued(struct thread_entry *thread)
{
return thread->tmo.next != TMO_NOT_QUEUED;
}
static inline void tmo_set_dequeued(struct thread_entry *thread)
{
thread->tmo.next = TMO_NOT_QUEUED;
}
static inline void tmo_queue_init(struct __tmo_queue *tmop)
{
ll_init(tmop);
}
static inline void tmo_queue_expire(struct __tmo_queue *tmop,
struct thread_entry *prev,
struct thread_entry *thread)
{
ll_remove_next(tmop, prev ? &prev->tmo : NULL);
tmo_set_dequeued(thread);
}
static inline void tmo_queue_remove(struct __tmo_queue *tmop,
struct thread_entry *thread)
{
if (tmo_is_queued(thread))
{
ll_remove(tmop, &thread->tmo);
tmo_set_dequeued(thread);
}
}
static inline void tmo_queue_register(struct __tmo_queue *tmop,
struct thread_entry *thread)
{
if (!tmo_is_queued(thread))
ll_insert_last(tmop, &thread->tmo);
}
static inline void wait_queue_init(struct __wait_queue *wqp)
{
lld_init(wqp);
}
static inline void wait_queue_register(struct thread_entry *thread)
{
lld_insert_last(thread->wqp, &thread->wq);
}
static inline struct __wait_queue *
wait_queue_ptr(struct thread_entry *thread)
{
return thread->wqp;
}
static inline struct __wait_queue *
wait_queue_remove(struct thread_entry *thread)
{
struct __wait_queue *wqp = thread->wqp;
thread->wqp = NULL;
lld_remove(wqp, &thread->wq);
return wqp;
}
static inline struct __wait_queue *
wait_queue_try_remove(struct thread_entry *thread)
{
struct __wait_queue *wqp = thread->wqp;
if (wqp)
{
thread->wqp = NULL;
lld_remove(wqp, &thread->wq);
}
return wqp;
}
static inline void blocker_init(struct blocker *bl)
{
bl->thread = NULL;
#ifdef HAVE_PRIORITY_SCHEDULING
bl->priority = PRIORITY_IDLE;
#endif
}
static inline void blocker_splay_init(struct blocker_splay *blsplay)
{
blocker_init(&blsplay->blocker);
#ifdef HAVE_PRIORITY_SCHEDULING
threadbit_clear(&blsplay->mask);
#endif
corelock_init(&blsplay->cl);
}
#endif /* THREAD_INTERNAL_H */