/*************************************************************************** * __________ __ ___. * Open \______ \ ____ ____ | | _\_ |__ _______ ___ * Source | _// _ \_/ ___\| |/ /| __ \ / _ \ \/ / * Jukebox | | ( <_> ) \___| < | \_\ ( <_> > < < * Firmware |____|_ /\____/ \___ >__|_ \|___ /\____/__/\_ \ * \/ \/ \/ \/ \/ * $Id$ * * Copyright (C) 2002 by Ulf Ralberg * * All files in this archive are subject to the GNU General Public License. * See the file COPYING in the source tree root for full license agreement. * * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY * KIND, either express or implied. * ****************************************************************************/ #ifndef THREAD_H #define THREAD_H #include "config.h" #include #include #include /* Priority scheduling (when enabled with HAVE_PRIORITY_SCHEDULING) works * by giving high priority threads more CPU time than less priority threads * when they need it. * * If software playback codec pcm buffer is going down to critical, codec * can change it own priority to REALTIME to override user interface and * prevent playback skipping. */ #define HIGHEST_PRIORITY 1 /* The highest possible thread priority */ #define LOWEST_PRIORITY 100 /* The lowest possible thread priority */ #define PRIORITY_REALTIME 1 #define PRIORITY_USER_INTERFACE 4 /* The main thread */ #define PRIORITY_RECORDING 4 /* Recording thread */ #define PRIORITY_PLAYBACK 4 /* or REALTIME when needed */ #define PRIORITY_BUFFERING 4 /* Codec buffering thread */ #define PRIORITY_SYSTEM 6 /* All other firmware threads */ #define PRIORITY_BACKGROUND 8 /* Normal application threads */ /* TODO: Only a minor tweak to create_thread would be needed to let * thread slots be caller allocated - no essential threading functionality * depends upon an array */ #if CONFIG_CODEC == SWCODEC #ifdef HAVE_RECORDING #define MAXTHREADS 18 #else #define MAXTHREADS 17 #endif #else #define MAXTHREADS 11 #endif /* CONFIG_CODE == * */ #define DEFAULT_STACK_SIZE 0x400 /* Bytes */ /** * "Busy" values that can be swapped into a variable to indicate * that the variable or object pointed to is in use by another processor * core. When accessed, the busy value is swapped-in while the current * value is atomically returned. If the swap returns the busy value, * the processor should retry the operation until some other value is * returned. When modification is finished, the new value should be * written which unlocks it and updates it atomically. * * Procedure: * while ((curr_value = swap(&variable, BUSY_VALUE)) == BUSY_VALUE); * * Modify/examine object at mem location or variable. Create "new_value" * as suitable. * * variable = new_value or curr_value; * * To check a value for busy and perform an operation if not: * curr_value = swap(&variable, BUSY_VALUE); * * if (curr_value != BUSY_VALUE) * { * Modify/examine object at mem location or variable. Create "new_value" * as suitable. * variable = new_value or curr_value; * } * else * { * Do nothing - already busy * } * * Only ever restore when an actual value is returned or else it could leave * the variable locked permanently if another processor unlocked in the * meantime. The next access attempt would deadlock for all processors since * an abandoned busy status would be left behind. */ #define STATE_BUSYuptr ((void*)UINTPTR_MAX) #define STATE_BUSYu8 UINT8_MAX #define STATE_BUSYi INT_MIN #ifndef SIMULATOR /* Need to keep structures inside the header file because debug_menu * needs them. */ #ifdef CPU_COLDFIRE struct regs { unsigned int macsr; /* 0 - EMAC status register */ unsigned int d[6]; /* 4-24 - d2-d7 */ unsigned int a[5]; /* 28-44 - a2-a6 */ void *sp; /* 48 - Stack pointer (a7) */ void *start; /* 52 - Thread start address, or NULL when started */ }; #elif CONFIG_CPU == SH7034 struct regs { unsigned int r[7]; /* 0-24 - Registers r8 thru r14 */ void *sp; /* 28 - Stack pointer (r15) */ void *pr; /* 32 - Procedure register */ void *start; /* 36 - Thread start address, or NULL when started */ }; #elif defined(CPU_ARM) struct regs { unsigned int r[8]; /* 0-28 - Registers r4-r11 */ void *sp; /* 32 - Stack pointer (r13) */ unsigned int lr; /* 36 - r14 (lr) */ void *start; /* 40 - Thread start address, or NULL when started */ }; #endif /* CONFIG_CPU */ #else struct regs { void *t; /* Simulator OS thread */ void *c; /* Condition for blocking and sync */ void (*start)(void); /* Start function */ }; #endif /* !SIMULATOR */ /* NOTE: The use of the word "queue" may also refer to a linked list of threads being maintainted that are normally dealt with in FIFO order and not nescessarily 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, #if NUM_CORES > 1 STATE_BUSY = STATE_BUSYu8, /* Thread slot is being examined */ #endif }; #if NUM_CORES > 1 #define THREAD_DESTRUCT ((const char *)0x84905617) #endif /* Link information for lists thread is in */ struct thread_entry; /* forward */ struct thread_list { struct thread_entry *prev; /* Previous thread in a list */ struct thread_entry *next; /* Next thread in a list */ }; /* Small objects for core-wise mutual exclusion */ #if CONFIG_CORELOCK == SW_CORELOCK /* No reliable atomic instruction available - use Peterson's algorithm */ struct corelock { volatile unsigned char myl[NUM_CORES]; volatile unsigned char turn; } __attribute__((packed)); void corelock_init(struct corelock *cl); void corelock_lock(struct corelock *cl); int corelock_try_lock(struct corelock *cl); void corelock_unlock(struct corelock *cl); #elif CONFIG_CORELOCK == CORELOCK_SWAP /* Use native atomic swap/exchange instruction */ struct corelock { unsigned char locked; } __attribute__((packed)); #define corelock_init(cl) \ ({ (cl)->locked = 0; }) #define corelock_lock(cl) \ ({ while (test_and_set(&(cl)->locked, 1)); }) #define corelock_try_lock(cl) \ ({ test_and_set(&(cl)->locked, 1) ? 0 : 1; }) #define corelock_unlock(cl) \ ({ (cl)->locked = 0; }) #else /* No atomic corelock op needed or just none defined */ #define corelock_init(cl) #define corelock_lock(cl) #define corelock_try_lock(cl) #define corelock_unlock(cl) #endif /* core locking selection */ struct thread_queue { struct thread_entry *queue; /* list of threads waiting - _must_ be first member */ #if CONFIG_CORELOCK == SW_CORELOCK struct corelock cl; /* lock for atomic list operations */ #endif }; /* 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 */ void *stack; /* Pointer to top of stack */ const char *name; /* Thread name */ long tmo_tick; /* Tick when thread should be woken from timeout */ struct thread_list l; /* Links for blocked/waking/running - circular linkage in both directions */ struct thread_list tmo; /* Links for timeout list - Self-pointer-terminated in reverse direction, NULL-terminated in forward direction */ struct thread_queue *bqp; /* Pointer to list variable in kernel object where thread is blocked - used for implicit unblock and explicit wake */ #if CONFIG_CORELOCK == SW_CORELOCK struct thread_entry **bqnlp; /* Pointer to list variable in kernel object where thread is blocked - non-locked operations will be used */ #endif struct thread_entry *queue; /* List of threads waiting for thread to be removed */ #ifdef HAVE_EXTENDED_MESSAGING_AND_NAME intptr_t retval; /* Return value from a blocked operation */ #endif #ifdef HAVE_PRIORITY_SCHEDULING long last_run; /* Last tick when started */ #endif unsigned short stack_size; /* Size of stack in bytes */ #ifdef HAVE_PRIORITY_SCHEDULING unsigned char priority; /* Current priority */ unsigned char priority_x; /* Inherited priority - right now just a runtime guarantee flag */ #endif unsigned char state; /* Thread slot state (STATE_*) */ #if NUM_CORES > 1 unsigned char core; /* The core to which thread belongs */ #endif #ifdef HAVE_SCHEDULER_BOOSTCTRL unsigned char boosted; /* CPU frequency boost flag */ #endif #if CONFIG_CORELOCK == SW_CORELOCK struct corelock cl; /* Corelock to lock thread slot */ #endif }; #if NUM_CORES > 1 /* Operations to be performed just before stopping a thread and starting a new one if specified before calling switch_thread */ #define TBOP_UNLOCK_LIST 0x01 /* Set a pointer variable address var_ptrp */ #if CONFIG_CORELOCK == CORELOCK_SWAP #define TBOP_SET_VARi 0x02 /* Set an int at address var_ip */ #define TBOP_SET_VARu8 0x03 /* Set an unsigned char at address var_u8p */ #define TBOP_VAR_TYPE_MASK 0x03 /* Mask for variable type*/ #endif /* CONFIG_CORELOCK */ #define TBOP_UNLOCK_CORELOCK 0x04 #define TBOP_UNLOCK_THREAD 0x08 /* Unlock a thread's slot */ #define TBOP_UNLOCK_CURRENT 0x10 /* Unlock the current thread's slot */ #define TBOP_SWITCH_CORE 0x20 /* Call the core switch preparation routine */ struct thread_blk_ops { #if CONFIG_CORELOCK != SW_CORELOCK union { int var_iv; /* int variable value to set */ uint8_t var_u8v; /* unsigned char valur to set */ struct thread_entry *list_v; /* list pointer queue value to set */ }; #endif union { #if CONFIG_CORELOCK != SW_CORELOCK int *var_ip; /* pointer to int variable */ uint8_t *var_u8p; /* pointer to unsigned char varuable */ #endif struct thread_queue *list_p; /* pointer to list variable */ }; #if CONFIG_CORELOCK == SW_CORELOCK struct corelock *cl_p; /* corelock to unlock */ struct thread_entry *thread; /* thread to unlock */ #elif CONFIG_CORELOCK == CORELOCK_SWAP unsigned char state; /* new thread state (performs unlock) */ #endif /* SOFTWARE_CORELOCK */ unsigned char flags; /* TBOP_* flags */ }; #endif /* NUM_CORES > 1 */ /* Information kept for each core * Member 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 thread_entry *running; /* threads that are running */ struct thread_entry *timeout; /* threads that are on a timeout before running again */ /* "Shared" lists - cores interact in a synchronized manner - access is locked between cores and interrupts */ struct thread_queue waking; /* intermediate locked list that hold threads other core should wake up on next task switch */ long next_tmo_check; /* soonest time to check tmo threads */ #if NUM_CORES > 1 struct thread_blk_ops blk_ops; /* operations to perform when blocking a thread */ #endif /* NUM_CORES */ #ifdef HAVE_PRIORITY_SCHEDULING unsigned char highest_priority; #endif }; #ifdef HAVE_PRIORITY_SCHEDULING #define IF_PRIO(...) __VA_ARGS__ #else #define IF_PRIO(...) #endif /* Macros generate better code than an inline function is this case */ #if (defined (CPU_PP) || defined (CPU_ARM)) /* atomic */ #if CONFIG_CORELOCK == SW_CORELOCK #define test_and_set(a, v, cl) \ xchg8((a), (v), (cl)) /* atomic */ #define xchg8(a, v, cl) \ ({ uint32_t o; \ corelock_lock(cl); \ o = *(uint8_t *)(a); \ *(uint8_t *)(a) = (v); \ corelock_unlock(cl); \ o; }) #define xchg32(a, v, cl) \ ({ uint32_t o; \ corelock_lock(cl); \ o = *(uint32_t *)(a); \ *(uint32_t *)(a) = (v); \ corelock_unlock(cl); \ o; }) #define xchgptr(a, v, cl) \ ({ typeof (*(a)) o; \ corelock_lock(cl); \ o = *(a); \ *(a) = (v); \ corelock_unlock(cl); \ o; }) #elif CONFIG_CORELOCK == CORELOCK_SWAP /* atomic */ #define test_and_set(a, v, ...) \ xchg8((a), (v)) #define xchg8(a, v, ...) \ ({ uint32_t o; \ asm volatile( \ "swpb %0, %1, [%2]" \ : "=&r"(o) \ : "r"(v), \ "r"((uint8_t*)(a))); \ o; }) /* atomic */ #define xchg32(a, v, ...) \ ({ uint32_t o; \ asm volatile( \ "swp %0, %1, [%2]" \ : "=&r"(o) \ : "r"((uint32_t)(v)), \ "r"((uint32_t*)(a))); \ o; }) /* atomic */ #define xchgptr(a, v, ...) \ ({ typeof (*(a)) o; \ asm volatile( \ "swp %0, %1, [%2]" \ : "=&r"(o) \ : "r"(v), "r"(a)); \ o; }) #endif /* locking selection */ #elif defined (CPU_COLDFIRE) /* atomic */ /* one branch will be optimized away if v is a constant expression */ #define test_and_set(a, v, ...) \ ({ uint32_t o = 0; \ if (v) { \ asm volatile ( \ "bset.b #0, (%0)" \ : : "a"((uint8_t*)(a)) \ : "cc"); \ } else { \ asm volatile ( \ "bclr.b #0, (%0)" \ : : "a"((uint8_t*)(a)) \ : "cc"); \ } \ asm volatile ("sne.b %0" \ : "+d"(o)); \ o; }) #elif CONFIG_CPU == SH7034 /* atomic */ #define test_and_set(a, v, ...) \ ({ uint32_t o; \ asm volatile ( \ "tas.b @%2 \n" \ "mov #-1, %0 \n" \ "negc %0, %0 \n" \ : "=r"(o) \ : "M"((uint32_t)(v)), /* Value of_v must be 1 */ \ "r"((uint8_t *)(a))); \ o; }) #endif /* CONFIG_CPU == */ /* defaults for no asm version */ #ifndef test_and_set /* not atomic */ #define test_and_set(a, v, ...) \ ({ uint32_t o = *(uint8_t *)(a); \ *(uint8_t *)(a) = (v); \ o; }) #endif /* test_and_set */ #ifndef xchg8 /* not atomic */ #define xchg8(a, v, ...) \ ({ uint32_t o = *(uint8_t *)(a); \ *(uint8_t *)(a) = (v); \ o; }) #endif /* xchg8 */ #ifndef xchg32 /* not atomic */ #define xchg32(a, v, ...) \ ({ uint32_t o = *(uint32_t *)(a); \ *(uint32_t *)(a) = (v); \ o; }) #endif /* xchg32 */ #ifndef xchgptr /* not atomic */ #define xchgptr(a, v, ...) \ ({ typeof (*(a)) o = *(a); \ *(a) = (v); \ o; }) #endif /* xchgptr */ void core_idle(void); void core_wake(IF_COP_VOID(unsigned int core)); #define CREATE_THREAD_FROZEN 0x00000001 /* Thread is frozen at create time */ struct thread_entry* create_thread(void (*function)(void), void* stack, int stack_size, unsigned flags, const char *name IF_PRIO(, int priority) IF_COP(, unsigned int core)); #ifdef HAVE_SCHEDULER_BOOSTCTRL void trigger_cpu_boost(void); void cancel_cpu_boost(void); #else #define trigger_cpu_boost() #define cancel_cpu_boost() #endif void thread_thaw(struct thread_entry *thread); void thread_wait(struct thread_entry *thread); void remove_thread(struct thread_entry *thread); void switch_thread(struct thread_entry *old); void sleep_thread(int ticks); /** * Setup to allow using thread queues as locked or non-locked without speed * sacrifices in both core locking types. * * The blocking/waking function inline two different version of the real * function into the stubs when a software or other separate core locking * mechanism is employed. * * When a simple test-and-set or similar instruction is available, locking * has no cost and so one version is used and the internal worker is called * directly. * * CORELOCK_NONE is treated the same as when an atomic instruction can be * used. */ /* Blocks the current thread on a thread queue */ #if CONFIG_CORELOCK == SW_CORELOCK void block_thread(struct thread_queue *tq); void block_thread_no_listlock(struct thread_entry **list); #else void _block_thread(struct thread_queue *tq); static inline void block_thread(struct thread_queue *tq) { _block_thread(tq); } static inline void block_thread_no_listlock(struct thread_entry **list) { _block_thread((struct thread_queue *)list); } #endif /* CONFIG_CORELOCK */ /* Blocks the current thread on a thread queue for a max amount of time * There is no "_no_listlock" version because timeout blocks without sync on * the blocking queues is not permitted since either core could access the * list at any time to do an implicit wake. In other words, objects with * timeout support require lockable queues. */ void block_thread_w_tmo(struct thread_queue *tq, int timeout); /* Wakes up the thread at the head of the queue */ #define THREAD_WAKEUP_NONE ((struct thread_entry *)NULL) #define THREAD_WAKEUP_MISSING ((struct thread_entry *)(NULL+1)) #if CONFIG_CORELOCK == SW_CORELOCK struct thread_entry * wakeup_thread(struct thread_queue *tq); struct thread_entry * wakeup_thread_no_listlock(struct thread_entry **list); #else struct thread_entry * _wakeup_thread(struct thread_queue *list); static inline struct thread_entry * wakeup_thread(struct thread_queue *tq) { return _wakeup_thread(tq); } static inline struct thread_entry * wakeup_thread_no_listlock(struct thread_entry **list) { return _wakeup_thread((struct thread_queue *)list); } #endif /* CONFIG_CORELOCK */ /* Initialize a thread_queue object. */ static inline void thread_queue_init(struct thread_queue *tq) { tq->queue = NULL; IF_SWCL(corelock_init(&tq->cl);) } /* A convenience function for waking an entire queue of threads. */ static inline void thread_queue_wake(struct thread_queue *tq) { while (wakeup_thread(tq) != NULL); } /* The no-listlock version of thread_queue_wake() */ static inline void thread_queue_wake_no_listlock(struct thread_entry **list) { while (wakeup_thread_no_listlock(list) != NULL); } #ifdef HAVE_PRIORITY_SCHEDULING int thread_set_priority(struct thread_entry *thread, int priority); int thread_get_priority(struct thread_entry *thread); /* Yield that guarantees thread execution once per round regardless of thread's scheduler priority - basically a transient realtime boost without altering the scheduler's thread precedence. */ void priority_yield(void); #else #define priority_yield yield #endif /* HAVE_PRIORITY_SCHEDULING */ #if NUM_CORES > 1 unsigned int switch_core(unsigned int new_core); #endif struct thread_entry * thread_get_current(void); void init_threads(void); int thread_stack_usage(const struct thread_entry *thread); #if NUM_CORES > 1 int idle_stack_usage(unsigned int core); #endif void thread_get_name(char *buffer, int size, struct thread_entry *thread); #ifdef RB_PROFILE void profile_thread(void); #endif #endif /* THREAD_H */