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			2426 lines
		
	
	
	
		
			68 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			2426 lines
		
	
	
	
		
			68 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /**********************************************************************
 | |
| 
 | |
|   cont.c -
 | |
| 
 | |
|   $Author$
 | |
|   created at: Thu May 23 09:03:43 2007
 | |
| 
 | |
|   Copyright (C) 2007 Koichi Sasada
 | |
| 
 | |
| **********************************************************************/
 | |
| 
 | |
| #include "internal.h"
 | |
| #include "vm_core.h"
 | |
| #include "gc.h"
 | |
| #include "eval_intern.h"
 | |
| #include "mjit.h"
 | |
| 
 | |
| #include COROUTINE_H
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| 
 | |
| #ifndef _WIN32
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| #include <unistd.h>
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| #include <sys/mman.h>
 | |
| #endif
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| 
 | |
| static const int DEBUG = 0;
 | |
| 
 | |
| #define RB_PAGE_SIZE (pagesize)
 | |
| #define RB_PAGE_MASK (~(RB_PAGE_SIZE - 1))
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| static long pagesize;
 | |
| 
 | |
| static const rb_data_type_t cont_data_type, fiber_data_type;
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| static VALUE rb_cContinuation;
 | |
| static VALUE rb_cFiber;
 | |
| static VALUE rb_eFiberError;
 | |
| #ifdef RB_EXPERIMENTAL_FIBER_POOL
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| static VALUE rb_cFiberPool;
 | |
| #endif
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| 
 | |
| #define CAPTURE_JUST_VALID_VM_STACK 1
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| 
 | |
| // Defined in `coroutine/$arch/Context.h`:
 | |
| #ifdef COROUTINE_LIMITED_ADDRESS_SPACE
 | |
| #define FIBER_POOL_ALLOCATION_FREE
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| #define FIBER_POOL_INITIAL_SIZE 8
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| #define FIBER_POOL_ALLOCATION_MAXIMUM_SIZE 32
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| #else
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| #define FIBER_POOL_INITIAL_SIZE 32
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| #define FIBER_POOL_ALLOCATION_MAXIMUM_SIZE 1024
 | |
| #endif
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| 
 | |
| enum context_type {
 | |
|     CONTINUATION_CONTEXT = 0,
 | |
|     FIBER_CONTEXT = 1
 | |
| };
 | |
| 
 | |
| struct cont_saved_vm_stack {
 | |
|     VALUE *ptr;
 | |
| #ifdef CAPTURE_JUST_VALID_VM_STACK
 | |
|     size_t slen;  /* length of stack (head of ec->vm_stack) */
 | |
|     size_t clen;  /* length of control frames (tail of ec->vm_stack) */
 | |
| #endif
 | |
| };
 | |
| 
 | |
| struct fiber_pool;
 | |
| 
 | |
| // Represents a single stack.
 | |
| struct fiber_pool_stack {
 | |
|     // A pointer to the memory allocation (lowest address) for the stack.
 | |
|     void * base;
 | |
| 
 | |
|     // The current stack pointer, taking into account the direction of the stack.
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|     void * current;
 | |
| 
 | |
|     // The size of the stack excluding any guard pages.
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|     size_t size;
 | |
| 
 | |
|     // The available stack capacity w.r.t. the current stack offset.
 | |
|     size_t available;
 | |
| 
 | |
|     // The pool this stack should be allocated from.
 | |
|     struct fiber_pool * pool;
 | |
| 
 | |
|     // If the stack is allocated, the allocation it came from.
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|     struct fiber_pool_allocation * allocation;
 | |
| };
 | |
| 
 | |
| // A linked list of vacant (unused) stacks.
 | |
| // This structure is stored in the first page of a stack if it is not in use.
 | |
| // @sa fiber_pool_vacancy_pointer
 | |
| struct fiber_pool_vacancy {
 | |
|     // Details about the vacant stack:
 | |
|     struct fiber_pool_stack stack;
 | |
| 
 | |
|     // The vacancy linked list.
 | |
| #ifdef FIBER_POOL_ALLOCATION_FREE
 | |
|     struct fiber_pool_vacancy * previous;
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| #endif
 | |
|     struct fiber_pool_vacancy * next;
 | |
| };
 | |
| 
 | |
| // Manages singly linked list of mapped regions of memory which contains 1 more more stack:
 | |
| //
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| // base = +-------------------------------+-----------------------+  +
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| //        |VM Stack       |VM Stack       |                       |  |
 | |
| //        |               |               |                       |  |
 | |
| //        |               |               |                       |  |
 | |
| //        +-------------------------------+                       |  |
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| //        |Machine Stack  |Machine Stack  |                       |  |
 | |
| //        |               |               |                       |  |
 | |
| //        |               |               |                       |  |
 | |
| //        |               |               | .  .  .  .            |  |  size
 | |
| //        |               |               |                       |  |
 | |
| //        |               |               |                       |  |
 | |
| //        |               |               |                       |  |
 | |
| //        |               |               |                       |  |
 | |
| //        |               |               |                       |  |
 | |
| //        +-------------------------------+                       |  |
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| //        |Guard Page     |Guard Page     |                       |  |
 | |
| //        +-------------------------------+-----------------------+  v
 | |
| //
 | |
| //        +------------------------------------------------------->
 | |
| //
 | |
| //                                  count
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| //
 | |
| struct fiber_pool_allocation {
 | |
|     // A pointer to the memory mapped region.
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|     void * base;
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| 
 | |
|     // The size of the individual stacks.
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|     size_t size;
 | |
| 
 | |
|     // The stride of individual stacks (including any guard pages or other accounting details).
 | |
|     size_t stride;
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| 
 | |
|     // The number of stacks that were allocated.
 | |
|     size_t count;
 | |
| 
 | |
| #ifdef FIBER_POOL_ALLOCATION_FREE
 | |
|     // The number of stacks used in this allocation.
 | |
|     size_t used;
 | |
| #endif
 | |
| 
 | |
|     struct fiber_pool * pool;
 | |
| 
 | |
|     // The allocation linked list.
 | |
| #ifdef FIBER_POOL_ALLOCATION_FREE
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|     struct fiber_pool_allocation * previous;
 | |
| #endif
 | |
|     struct fiber_pool_allocation * next;
 | |
| };
 | |
| 
 | |
| // A fiber pool manages vacant stacks to reduce the overhead of creating fibers.
 | |
| struct fiber_pool {
 | |
|     // A singly-linked list of allocations which contain 1 or more stacks each.
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|     struct fiber_pool_allocation * allocations;
 | |
| 
 | |
|     // Provides O(1) stack "allocation":
 | |
|     struct fiber_pool_vacancy * vacancies;
 | |
| 
 | |
|     // The size of the stack allocations (excluding any guard page).
 | |
|     size_t size;
 | |
| 
 | |
|     // The total number of stacks that have been allocated in this pool.
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|     size_t count;
 | |
| 
 | |
|     // The initial number of stacks to allocate.
 | |
|     size_t initial_count;
 | |
| 
 | |
|     // Whether to madvise(free) the stack or not:
 | |
|     int free_stacks;
 | |
| 
 | |
|     // The number of stacks that have been used in this pool.
 | |
|     size_t used;
 | |
| 
 | |
|     // The amount to allocate for the vm_stack:
 | |
|     size_t vm_stack_size;
 | |
| };
 | |
| 
 | |
| typedef struct rb_context_struct {
 | |
|     enum context_type type;
 | |
|     int argc;
 | |
|     VALUE self;
 | |
|     VALUE value;
 | |
| 
 | |
|     struct cont_saved_vm_stack saved_vm_stack;
 | |
| 
 | |
|     struct {
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|         VALUE *stack;
 | |
|         VALUE *stack_src;
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|         size_t stack_size;
 | |
|     } machine;
 | |
|     rb_execution_context_t saved_ec;
 | |
|     rb_jmpbuf_t jmpbuf;
 | |
|     rb_ensure_entry_t *ensure_array;
 | |
|     /* Pointer to MJIT info about the continuation.  */
 | |
|     struct mjit_cont *mjit_cont;
 | |
| } rb_context_t;
 | |
| 
 | |
| 
 | |
| /*
 | |
|  * Fiber status:
 | |
|  *    [Fiber.new] ------> FIBER_CREATED
 | |
|  *                        | [Fiber#resume]
 | |
|  *                        v
 | |
|  *                   +--> FIBER_RESUMED ----+
 | |
|  *    [Fiber#resume] |    | [Fiber.yield]   |
 | |
|  *                   |    v                 |
 | |
|  *                   +-- FIBER_SUSPENDED    | [Terminate]
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|  *                                          |
 | |
|  *                       FIBER_TERMINATED <-+
 | |
|  */
 | |
| enum fiber_status {
 | |
|     FIBER_CREATED,
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|     FIBER_RESUMED,
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|     FIBER_SUSPENDED,
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|     FIBER_TERMINATED
 | |
| };
 | |
| 
 | |
| #define FIBER_CREATED_P(fiber)    ((fiber)->status == FIBER_CREATED)
 | |
| #define FIBER_RESUMED_P(fiber)    ((fiber)->status == FIBER_RESUMED)
 | |
| #define FIBER_SUSPENDED_P(fiber)  ((fiber)->status == FIBER_SUSPENDED)
 | |
| #define FIBER_TERMINATED_P(fiber) ((fiber)->status == FIBER_TERMINATED)
 | |
| #define FIBER_RUNNABLE_P(fiber)   (FIBER_CREATED_P(fiber) || FIBER_SUSPENDED_P(fiber))
 | |
| 
 | |
| struct rb_fiber_struct {
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|     rb_context_t cont;
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|     VALUE first_proc;
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|     struct rb_fiber_struct *prev;
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|     BITFIELD(enum fiber_status, status, 2);
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|     /* If a fiber invokes "transfer",
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|      * then this fiber can't "resume" any more after that.
 | |
|      * You shouldn't mix "transfer" and "resume".
 | |
|      */
 | |
|     unsigned int transferred : 1;
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| 
 | |
|     struct coroutine_context context;
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|     struct fiber_pool_stack stack;
 | |
| };
 | |
| 
 | |
| static struct fiber_pool shared_fiber_pool = {NULL, NULL, 0, 0, 0, 0};
 | |
| 
 | |
| /*
 | |
|  * FreeBSD require a first (i.e. addr) argument of mmap(2) is not NULL
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|  * if MAP_STACK is passed.
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|  * http://www.FreeBSD.org/cgi/query-pr.cgi?pr=158755
 | |
|  */
 | |
| #if defined(MAP_STACK) && !defined(__FreeBSD__) && !defined(__FreeBSD_kernel__)
 | |
| #define FIBER_STACK_FLAGS (MAP_PRIVATE | MAP_ANON | MAP_STACK)
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| #else
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| #define FIBER_STACK_FLAGS (MAP_PRIVATE | MAP_ANON)
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| #endif
 | |
| 
 | |
| #define ERRNOMSG strerror(errno)
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| 
 | |
| // Locates the stack vacancy details for the given stack.
 | |
| // Requires that fiber_pool_vacancy fits within one page.
 | |
| inline static struct fiber_pool_vacancy *
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| fiber_pool_vacancy_pointer(void * base, size_t size)
 | |
| {
 | |
|     STACK_GROW_DIR_DETECTION;
 | |
| 
 | |
|     return (struct fiber_pool_vacancy *)(
 | |
|         (char*)base + STACK_DIR_UPPER(0, size - RB_PAGE_SIZE)
 | |
|     );
 | |
| }
 | |
| 
 | |
| // Reset the current stack pointer and available size of the given stack.
 | |
| inline static void
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| fiber_pool_stack_reset(struct fiber_pool_stack * stack)
 | |
| {
 | |
|     STACK_GROW_DIR_DETECTION;
 | |
| 
 | |
|     stack->current = (char*)stack->base + STACK_DIR_UPPER(0, stack->size);
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|     stack->available = stack->size;
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| }
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| 
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| // A pointer to the base of the current unused portion of the stack.
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| inline static void *
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| fiber_pool_stack_base(struct fiber_pool_stack * stack)
 | |
| {
 | |
|     STACK_GROW_DIR_DETECTION;
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| 
 | |
|     VM_ASSERT(stack->current);
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| 
 | |
|     return STACK_DIR_UPPER(stack->current, (char*)stack->current - stack->available);
 | |
| }
 | |
| 
 | |
| // Allocate some memory from the stack. Used to allocate vm_stack inline with machine stack.
 | |
| // @sa fiber_initialize_coroutine
 | |
| inline static void *
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| fiber_pool_stack_alloca(struct fiber_pool_stack * stack, size_t offset)
 | |
| {
 | |
|     STACK_GROW_DIR_DETECTION;
 | |
| 
 | |
|     if (DEBUG) fprintf(stderr, "fiber_pool_stack_alloca(%p): %"PRIuSIZE"/%"PRIuSIZE"\n", stack, offset, stack->available);
 | |
|     VM_ASSERT(stack->available >= offset);
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| 
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|     // The pointer to the memory being allocated:
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|     void * pointer = STACK_DIR_UPPER(stack->current, (char*)stack->current - offset);
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| 
 | |
|     // Move the stack pointer:
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|     stack->current = STACK_DIR_UPPER((char*)stack->current + offset, (char*)stack->current - offset);
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|     stack->available -= offset;
 | |
| 
 | |
|     return pointer;
 | |
| }
 | |
| 
 | |
| // Reset the current stack pointer and available size of the given stack.
 | |
| inline static void
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| fiber_pool_vacancy_reset(struct fiber_pool_vacancy * vacancy)
 | |
| {
 | |
|     fiber_pool_stack_reset(&vacancy->stack);
 | |
| 
 | |
|     // Consume one page of the stack because it's used for the vacancy list:
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|     fiber_pool_stack_alloca(&vacancy->stack, RB_PAGE_SIZE);
 | |
| }
 | |
| 
 | |
| inline static struct fiber_pool_vacancy *
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| fiber_pool_vacancy_push(struct fiber_pool_vacancy * vacancy, struct fiber_pool_vacancy * head)
 | |
| {
 | |
|     vacancy->next = head;
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| 
 | |
| #ifdef FIBER_POOL_ALLOCATION_FREE
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|     if (head) {
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|         head->previous = vacancy;
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|     }
 | |
| #endif
 | |
| 
 | |
|     return vacancy;
 | |
| }
 | |
| 
 | |
| #ifdef FIBER_POOL_ALLOCATION_FREE
 | |
| static void
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| fiber_pool_vacancy_remove(struct fiber_pool_vacancy * vacancy)
 | |
| {
 | |
|     if (vacancy->next) {
 | |
|         vacancy->next->previous = vacancy->previous;
 | |
|     }
 | |
| 
 | |
|     if (vacancy->previous) {
 | |
|         vacancy->previous->next = vacancy->next;
 | |
|     }
 | |
|     else {
 | |
|         // It's the head of the list:
 | |
|         vacancy->stack.pool->vacancies = vacancy->next;
 | |
|     }
 | |
| }
 | |
| 
 | |
| inline static struct fiber_pool_vacancy *
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| fiber_pool_vacancy_pop(struct fiber_pool * pool)
 | |
| {
 | |
|     struct fiber_pool_vacancy * vacancy = pool->vacancies;
 | |
| 
 | |
|     if (vacancy) {
 | |
|         fiber_pool_vacancy_remove(vacancy);
 | |
|     }
 | |
| 
 | |
|     return vacancy;
 | |
| }
 | |
| #else
 | |
| inline static struct fiber_pool_vacancy *
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| fiber_pool_vacancy_pop(struct fiber_pool * pool)
 | |
| {
 | |
|     struct fiber_pool_vacancy * vacancy = pool->vacancies;
 | |
| 
 | |
|     if (vacancy) {
 | |
|         pool->vacancies = vacancy->next;
 | |
|     }
 | |
| 
 | |
|     return vacancy;
 | |
| }
 | |
| #endif
 | |
| 
 | |
| // Initialize the vacant stack. The [base, size] allocation should not include the guard page.
 | |
| // @param base The pointer to the lowest address of the allocated memory.
 | |
| // @param size The size of the allocated memory.
 | |
| inline static struct fiber_pool_vacancy *
 | |
| fiber_pool_vacancy_initialize(struct fiber_pool * fiber_pool, struct fiber_pool_vacancy * vacancies, void * base, size_t size)
 | |
| {
 | |
|     struct fiber_pool_vacancy * vacancy = fiber_pool_vacancy_pointer(base, size);
 | |
| 
 | |
|     vacancy->stack.base = base;
 | |
|     vacancy->stack.size = size;
 | |
| 
 | |
|     fiber_pool_vacancy_reset(vacancy);
 | |
| 
 | |
|     vacancy->stack.pool = fiber_pool;
 | |
| 
 | |
|     return fiber_pool_vacancy_push(vacancy, vacancies);
 | |
| }
 | |
| 
 | |
| // Allocate a maximum of count stacks, size given by stride.
 | |
| // @param count the number of stacks to allocate / were allocated.
 | |
| // @param stride the size of the individual stacks.
 | |
| // @return [void *] the allocated memory or NULL if allocation failed.
 | |
| inline static void *
 | |
| fiber_pool_allocate_memory(size_t * count, size_t stride)
 | |
| {
 | |
|     // We use a divide-by-2 strategy to try and allocate memory. We are trying
 | |
|     // to allocate `count` stacks. In normal situation, this won't fail. But
 | |
|     // if we ran out of address space, or we are allocating more memory than
 | |
|     // the system would allow (e.g. overcommit * physical memory + swap), we
 | |
|     // divide count by two and try again. This condition should only be
 | |
|     // encountered in edge cases, but we handle it here gracefully.
 | |
|     while (*count > 1) {
 | |
| #if defined(_WIN32)
 | |
|         void * base = VirtualAlloc(0, (*count)*stride, MEM_COMMIT, PAGE_READWRITE);
 | |
| 
 | |
|         if (!base) {
 | |
|             *count = (*count) >> 1;
 | |
|         }
 | |
|         else {
 | |
|             return base;
 | |
|         }
 | |
| #else
 | |
|         errno = 0;
 | |
|         void * base = mmap(NULL, (*count)*stride, PROT_READ | PROT_WRITE, FIBER_STACK_FLAGS, -1, 0);
 | |
| 
 | |
|         if (base == MAP_FAILED) {
 | |
|             // If the allocation fails, count = count / 2, and try again.
 | |
|             *count = (*count) >> 1;
 | |
|         }
 | |
|         else {
 | |
|             return base;
 | |
|         }
 | |
| #endif
 | |
|     }
 | |
| 
 | |
|     return NULL;
 | |
| }
 | |
| 
 | |
| // Given an existing fiber pool, expand it by the specified number of stacks.
 | |
| // @param count the maximum number of stacks to allocate.
 | |
| // @return the allocated fiber pool.
 | |
| // @sa fiber_pool_allocation_free
 | |
| static struct fiber_pool_allocation *
 | |
| fiber_pool_expand(struct fiber_pool * fiber_pool, size_t count)
 | |
| {
 | |
|     STACK_GROW_DIR_DETECTION;
 | |
| 
 | |
|     size_t size = fiber_pool->size;
 | |
|     size_t stride = size + RB_PAGE_SIZE;
 | |
| 
 | |
|     // Allocate the memory required for the stacks:
 | |
|     void * base = fiber_pool_allocate_memory(&count, stride);
 | |
| 
 | |
|     if (base == NULL) {
 | |
|         rb_raise(rb_eFiberError, "can't alloc machine stack to fiber (%"PRIuSIZE" x %"PRIuSIZE" bytes): %s", count, size, ERRNOMSG);
 | |
|     }
 | |
| 
 | |
|     struct fiber_pool_vacancy * vacancies = fiber_pool->vacancies;
 | |
|     struct fiber_pool_allocation * allocation = RB_ALLOC(struct fiber_pool_allocation);
 | |
| 
 | |
|     // Initialize fiber pool allocation:
 | |
|     allocation->base = base;
 | |
|     allocation->size = size;
 | |
|     allocation->stride = stride;
 | |
|     allocation->count = count;
 | |
| #ifdef FIBER_POOL_ALLOCATION_FREE
 | |
|     allocation->used = 0;
 | |
| #endif
 | |
|     allocation->pool = fiber_pool;
 | |
| 
 | |
|     if (DEBUG) {
 | |
|         fprintf(stderr, "fiber_pool_expand(%"PRIuSIZE"): %p, %"PRIuSIZE"/%"PRIuSIZE" x [%"PRIuSIZE":%"PRIuSIZE"]\n",
 | |
|                 count, fiber_pool, fiber_pool->used, fiber_pool->count, size, fiber_pool->vm_stack_size);
 | |
|     }
 | |
| 
 | |
|     // Iterate over all stacks, initializing the vacancy list:
 | |
|     for (size_t i = 0; i < count; i += 1) {
 | |
|         void * base = (char*)allocation->base + (stride * i);
 | |
|         void * page = (char*)base + STACK_DIR_UPPER(size, 0);
 | |
| 
 | |
| #if defined(_WIN32)
 | |
|         DWORD old_protect;
 | |
| 
 | |
|         if (!VirtualProtect(page, RB_PAGE_SIZE, PAGE_READWRITE | PAGE_GUARD, &old_protect)) {
 | |
|             VirtualFree(allocation->base, 0, MEM_RELEASE);
 | |
|             rb_raise(rb_eFiberError, "can't set a guard page: %s", ERRNOMSG);
 | |
|         }
 | |
| #else
 | |
|         if (mprotect(page, RB_PAGE_SIZE, PROT_NONE) < 0) {
 | |
|             munmap(allocation->base, count*stride);
 | |
|             rb_raise(rb_eFiberError, "can't set a guard page: %s", ERRNOMSG);
 | |
|         }
 | |
| #endif
 | |
| 
 | |
|         vacancies = fiber_pool_vacancy_initialize(
 | |
|             fiber_pool, vacancies,
 | |
|             (char*)base + STACK_DIR_UPPER(0, RB_PAGE_SIZE),
 | |
|             size
 | |
|         );
 | |
| 
 | |
| #ifdef FIBER_POOL_ALLOCATION_FREE
 | |
|         vacancies->stack.allocation = allocation;
 | |
| #endif
 | |
|     }
 | |
| 
 | |
|     // Insert the allocation into the head of the pool:
 | |
|     allocation->next = fiber_pool->allocations;
 | |
| 
 | |
| #ifdef FIBER_POOL_ALLOCATION_FREE
 | |
|     if (allocation->next) {
 | |
|         allocation->next->previous = allocation;
 | |
|     }
 | |
| 
 | |
|     allocation->previous = NULL;
 | |
| #endif
 | |
| 
 | |
|     fiber_pool->allocations = allocation;
 | |
|     fiber_pool->vacancies = vacancies;
 | |
|     fiber_pool->count += count;
 | |
| 
 | |
|     return allocation;
 | |
| }
 | |
| 
 | |
| // Initialize the specified fiber pool with the given number of stacks.
 | |
| // @param vm_stack_size The size of the vm stack to allocate.
 | |
| static void
 | |
| fiber_pool_initialize(struct fiber_pool * fiber_pool, size_t size, size_t count, size_t vm_stack_size)
 | |
| {
 | |
|     VM_ASSERT(vm_stack_size < size);
 | |
| 
 | |
|     fiber_pool->allocations = NULL;
 | |
|     fiber_pool->vacancies = NULL;
 | |
|     fiber_pool->size = ((size / RB_PAGE_SIZE) + 1) * RB_PAGE_SIZE;
 | |
|     fiber_pool->count = 0;
 | |
|     fiber_pool->initial_count = count;
 | |
|     fiber_pool->free_stacks = 1;
 | |
|     fiber_pool->used = 0;
 | |
| 
 | |
|     fiber_pool->vm_stack_size = vm_stack_size;
 | |
| 
 | |
|     fiber_pool_expand(fiber_pool, count);
 | |
| }
 | |
| 
 | |
| #ifdef FIBER_POOL_ALLOCATION_FREE
 | |
| // Free the list of fiber pool allocations.
 | |
| static void
 | |
| fiber_pool_allocation_free(struct fiber_pool_allocation * allocation)
 | |
| {
 | |
|     STACK_GROW_DIR_DETECTION;
 | |
| 
 | |
|     VM_ASSERT(allocation->used == 0);
 | |
| 
 | |
|     if (DEBUG) fprintf(stderr, "fiber_pool_allocation_free: %p base=%p count=%"PRIuSIZE"\n", allocation, allocation->base, allocation->count);
 | |
| 
 | |
|     size_t i;
 | |
|     for (i = 0; i < allocation->count; i += 1) {
 | |
|         void * base = (char*)allocation->base + (allocation->stride * i) + STACK_DIR_UPPER(0, RB_PAGE_SIZE);
 | |
| 
 | |
|         struct fiber_pool_vacancy * vacancy = fiber_pool_vacancy_pointer(base, allocation->size);
 | |
| 
 | |
|         // Pop the vacant stack off the free list:
 | |
|         fiber_pool_vacancy_remove(vacancy);
 | |
|     }
 | |
| 
 | |
| #ifdef _WIN32
 | |
|     VirtualFree(allocation->base, 0, MEM_RELEASE);
 | |
| #else
 | |
|     munmap(allocation->base, allocation->stride * allocation->count);
 | |
| #endif
 | |
| 
 | |
|     if (allocation->previous) {
 | |
|         allocation->previous->next = allocation->next;
 | |
|     }
 | |
|     else {
 | |
|         // We are the head of the list, so update the pool:
 | |
|         allocation->pool->allocations = allocation->next;
 | |
|     }
 | |
| 
 | |
|     if (allocation->next) {
 | |
|         allocation->next->previous = allocation->previous;
 | |
|     }
 | |
| 
 | |
|     allocation->pool->count -= allocation->count;
 | |
| 
 | |
|     ruby_xfree(allocation);
 | |
| }
 | |
| #endif
 | |
| 
 | |
| // Acquire a stack from the given fiber pool. If none are available, allocate more.
 | |
| static struct fiber_pool_stack
 | |
| fiber_pool_stack_acquire(struct fiber_pool * fiber_pool) {
 | |
|     struct fiber_pool_vacancy * vacancy = fiber_pool_vacancy_pop(fiber_pool);
 | |
| 
 | |
|     if (DEBUG) fprintf(stderr, "fiber_pool_stack_acquire: %p used=%"PRIuSIZE"\n", fiber_pool->vacancies, fiber_pool->used);
 | |
| 
 | |
|     if (!vacancy) {
 | |
|         const size_t maximum = FIBER_POOL_ALLOCATION_MAXIMUM_SIZE;
 | |
|         const size_t minimum = fiber_pool->initial_count;
 | |
| 
 | |
|         size_t count = fiber_pool->count;
 | |
|         if (count > maximum) count = maximum;
 | |
|         if (count < minimum) count = minimum;
 | |
| 
 | |
|         fiber_pool_expand(fiber_pool, count);
 | |
| 
 | |
|         // The free list should now contain some stacks:
 | |
|         VM_ASSERT(fiber_pool->vacancies);
 | |
| 
 | |
|         vacancy = fiber_pool_vacancy_pop(fiber_pool);
 | |
|     }
 | |
| 
 | |
|     VM_ASSERT(vacancy);
 | |
|     VM_ASSERT(vacancy->stack.base);
 | |
| 
 | |
|     // Take the top item from the free list:
 | |
|     fiber_pool->used += 1;
 | |
| 
 | |
| #ifdef FIBER_POOL_ALLOCATION_FREE
 | |
|     vacancy->stack.allocation->used += 1;
 | |
| #endif
 | |
| 
 | |
|     fiber_pool_stack_reset(&vacancy->stack);
 | |
| 
 | |
|     return vacancy->stack;
 | |
| }
 | |
| 
 | |
| // We advise the operating system that the stack memory pages are no longer being used.
 | |
| // This introduce some performance overhead but allows system to relaim memory when there is pressure.
 | |
| static inline void
 | |
| fiber_pool_stack_free(struct fiber_pool_stack * stack)
 | |
| {
 | |
|     void * base = fiber_pool_stack_base(stack);
 | |
|     size_t size = stack->available;
 | |
| 
 | |
|     // If this is not true, the vacancy information will almost certainly be destroyed:
 | |
|     VM_ASSERT(size <= (stack->size - RB_PAGE_SIZE));
 | |
| 
 | |
|     if (DEBUG) fprintf(stderr, "fiber_pool_stack_free: %p+%"PRIuSIZE" [base=%p, size=%"PRIuSIZE"]\n", base, size, stack->base, stack->size);
 | |
| 
 | |
| #if VM_CHECK_MODE > 0 && defined(MADV_DONTNEED)
 | |
|     // This immediately discards the pages and the memory is reset to zero.
 | |
|     madvise(base, size, MADV_DONTNEED);
 | |
| #elif defined(MADV_FREE_REUSABLE)
 | |
|     madvise(base, size, MADV_FREE_REUSABLE);
 | |
| #elif defined(MADV_FREE)
 | |
|     madvise(base, size, MADV_FREE);
 | |
| #elif defined(MADV_DONTNEED)
 | |
|     madvise(base, size, MADV_DONTNEED);
 | |
| #elif defined(_WIN32)
 | |
|     VirtualAlloc(base, size, MEM_RESET, PAGE_READWRITE);
 | |
|     // Not available in all versions of Windows.
 | |
|     //DiscardVirtualMemory(base, size);
 | |
| #endif
 | |
| }
 | |
| 
 | |
| // Release and return a stack to the vacancy list.
 | |
| static void
 | |
| fiber_pool_stack_release(struct fiber_pool_stack * stack)
 | |
| {
 | |
|     struct fiber_pool * pool = stack->pool;
 | |
|     struct fiber_pool_vacancy * vacancy = fiber_pool_vacancy_pointer(stack->base, stack->size);
 | |
| 
 | |
|     if (DEBUG) fprintf(stderr, "fiber_pool_stack_release: %p used=%"PRIuSIZE"\n", stack->base, stack->pool->used);
 | |
| 
 | |
|     // Copy the stack details into the vacancy area:
 | |
|     vacancy->stack = *stack;
 | |
|     // After this point, be careful about updating/using state in stack, since it's copied to the vacancy area.
 | |
| 
 | |
|     // Reset the stack pointers and reserve space for the vacancy data:
 | |
|     fiber_pool_vacancy_reset(vacancy);
 | |
| 
 | |
|     // Push the vacancy into the vancancies list:
 | |
|     pool->vacancies = fiber_pool_vacancy_push(vacancy, stack->pool->vacancies);
 | |
|     pool->used -= 1;
 | |
| 
 | |
| #ifdef FIBER_POOL_ALLOCATION_FREE
 | |
|     struct fiber_pool_allocation * allocation = stack->allocation;
 | |
| 
 | |
|     allocation->used -= 1;
 | |
| 
 | |
|     // Release address space and/or dirty memory:
 | |
|     if (allocation->used == 0) {
 | |
|         fiber_pool_allocation_free(allocation);
 | |
|     }
 | |
|     else if (stack->pool->free_stacks) {
 | |
|         fiber_pool_stack_free(&vacancy->stack);
 | |
|     }
 | |
| #else
 | |
|     // This is entirely optional, but clears the dirty flag from the stack memory, so it won't get swapped to disk when there is memory pressure:
 | |
|     if (stack->pool->free_stacks) {
 | |
|         fiber_pool_stack_free(&vacancy->stack);
 | |
|     }
 | |
| #endif
 | |
| }
 | |
| 
 | |
| static COROUTINE
 | |
| fiber_entry(struct coroutine_context * from, struct coroutine_context * to)
 | |
| {
 | |
|     rb_fiber_start();
 | |
| }
 | |
| 
 | |
| // Initialize a fiber's coroutine's machine stack and vm stack.
 | |
| static VALUE *
 | |
| fiber_initialize_coroutine(rb_fiber_t *fiber, size_t * vm_stack_size)
 | |
| {
 | |
|     struct fiber_pool * fiber_pool = fiber->stack.pool;
 | |
|     rb_execution_context_t *sec = &fiber->cont.saved_ec;
 | |
|     void * vm_stack = NULL;
 | |
| 
 | |
|     VM_ASSERT(fiber_pool != NULL);
 | |
| 
 | |
|     fiber->stack = fiber_pool_stack_acquire(fiber_pool);
 | |
|     vm_stack = fiber_pool_stack_alloca(&fiber->stack, fiber_pool->vm_stack_size);
 | |
|     *vm_stack_size = fiber_pool->vm_stack_size;
 | |
| 
 | |
| #ifdef COROUTINE_PRIVATE_STACK
 | |
|     coroutine_initialize(&fiber->context, fiber_entry, fiber_pool_stack_base(&fiber->stack), fiber->stack.available, sec->machine.stack_start);
 | |
|     // The stack for this execution context is still the main machine stack, so don't adjust it.
 | |
|     // If this is not managed correctly, you will fail in `rb_ec_stack_check`.
 | |
| 
 | |
|     // We limit the machine stack usage to the fiber stack size.
 | |
|     if (sec->machine.stack_maxsize > fiber->stack.available) {
 | |
|         sec->machine.stack_maxsize = fiber->stack.available;
 | |
|     }
 | |
| #else
 | |
|     coroutine_initialize(&fiber->context, fiber_entry, fiber_pool_stack_base(&fiber->stack), fiber->stack.available);
 | |
| 
 | |
|     // The stack for this execution context is the one we allocated:
 | |
|     sec->machine.stack_start = fiber->stack.current;
 | |
|     sec->machine.stack_maxsize = fiber->stack.available;
 | |
| #endif
 | |
| 
 | |
|     return vm_stack;
 | |
| }
 | |
| 
 | |
| // Release the stack from the fiber, it's execution context, and return it to the fiber pool.
 | |
| static void
 | |
| fiber_stack_release(rb_fiber_t * fiber)
 | |
| {
 | |
|     rb_execution_context_t *ec = &fiber->cont.saved_ec;
 | |
| 
 | |
|     if (DEBUG) fprintf(stderr, "fiber_stack_release: %p, stack.base=%p\n", fiber, fiber->stack.base);
 | |
| 
 | |
|     // Return the stack back to the fiber pool if it wasn't already:
 | |
|     if (fiber->stack.base) {
 | |
|         fiber_pool_stack_release(&fiber->stack);
 | |
|         fiber->stack.base = NULL;
 | |
|     }
 | |
| 
 | |
|     // The stack is no longer associated with this execution context:
 | |
|     rb_ec_clear_vm_stack(ec);
 | |
| }
 | |
| 
 | |
| static const char *
 | |
| fiber_status_name(enum fiber_status s)
 | |
| {
 | |
|     switch (s) {
 | |
|       case FIBER_CREATED: return "created";
 | |
|       case FIBER_RESUMED: return "resumed";
 | |
|       case FIBER_SUSPENDED: return "suspended";
 | |
|       case FIBER_TERMINATED: return "terminated";
 | |
|     }
 | |
|     VM_UNREACHABLE(fiber_status_name);
 | |
|     return NULL;
 | |
| }
 | |
| 
 | |
| static void
 | |
| fiber_verify(const rb_fiber_t *fiber)
 | |
| {
 | |
| #if VM_CHECK_MODE > 0
 | |
|     VM_ASSERT(fiber->cont.saved_ec.fiber_ptr == fiber);
 | |
| 
 | |
|     switch (fiber->status) {
 | |
|       case FIBER_RESUMED:
 | |
|         VM_ASSERT(fiber->cont.saved_ec.vm_stack != NULL);
 | |
|         break;
 | |
|       case FIBER_SUSPENDED:
 | |
|         VM_ASSERT(fiber->cont.saved_ec.vm_stack != NULL);
 | |
|         break;
 | |
|       case FIBER_CREATED:
 | |
|       case FIBER_TERMINATED:
 | |
|         /* TODO */
 | |
|         break;
 | |
|       default:
 | |
|         VM_UNREACHABLE(fiber_verify);
 | |
|     }
 | |
| #endif
 | |
| }
 | |
| 
 | |
| inline static void
 | |
| fiber_status_set(rb_fiber_t *fiber, enum fiber_status s)
 | |
| {
 | |
|     // if (DEBUG) fprintf(stderr, "fiber: %p, status: %s -> %s\n", (void *)fiber, fiber_status_name(fiber->status), fiber_status_name(s));
 | |
|     VM_ASSERT(!FIBER_TERMINATED_P(fiber));
 | |
|     VM_ASSERT(fiber->status != s);
 | |
|     fiber_verify(fiber);
 | |
|     fiber->status = s;
 | |
| }
 | |
| 
 | |
| static inline void
 | |
| ec_switch(rb_thread_t *th, rb_fiber_t *fiber)
 | |
| {
 | |
|     rb_execution_context_t *ec = &fiber->cont.saved_ec;
 | |
| 
 | |
|     ruby_current_execution_context_ptr = th->ec = ec;
 | |
| 
 | |
|     /*
 | |
|      * timer-thread may set trap interrupt on previous th->ec at any time;
 | |
|      * ensure we do not delay (or lose) the trap interrupt handling.
 | |
|      */
 | |
|     if (th->vm->main_thread == th && rb_signal_buff_size() > 0) {
 | |
|         RUBY_VM_SET_TRAP_INTERRUPT(ec);
 | |
|     }
 | |
| 
 | |
|     VM_ASSERT(ec->fiber_ptr->cont.self == 0 || ec->vm_stack != NULL);
 | |
| }
 | |
| 
 | |
| static rb_context_t *
 | |
| cont_ptr(VALUE obj)
 | |
| {
 | |
|     rb_context_t *cont;
 | |
| 
 | |
|     TypedData_Get_Struct(obj, rb_context_t, &cont_data_type, cont);
 | |
| 
 | |
|     return cont;
 | |
| }
 | |
| 
 | |
| static rb_fiber_t *
 | |
| fiber_ptr(VALUE obj)
 | |
| {
 | |
|     rb_fiber_t *fiber;
 | |
| 
 | |
|     TypedData_Get_Struct(obj, rb_fiber_t, &fiber_data_type, fiber);
 | |
|     if (!fiber) rb_raise(rb_eFiberError, "uninitialized fiber");
 | |
| 
 | |
|     return fiber;
 | |
| }
 | |
| 
 | |
| NOINLINE(static VALUE cont_capture(volatile int *volatile stat));
 | |
| 
 | |
| #define THREAD_MUST_BE_RUNNING(th) do { \
 | |
|         if (!(th)->ec->tag) rb_raise(rb_eThreadError, "not running thread"); \
 | |
|     } while (0)
 | |
| 
 | |
| static VALUE
 | |
| cont_thread_value(const rb_context_t *cont)
 | |
| {
 | |
|     return cont->saved_ec.thread_ptr->self;
 | |
| }
 | |
| 
 | |
| static void
 | |
| cont_compact(void *ptr)
 | |
| {
 | |
|     rb_context_t *cont = ptr;
 | |
| 
 | |
|     cont->value = rb_gc_location(cont->value);
 | |
|     rb_execution_context_update(&cont->saved_ec);
 | |
| }
 | |
| 
 | |
| static void
 | |
| cont_mark(void *ptr)
 | |
| {
 | |
|     rb_context_t *cont = ptr;
 | |
| 
 | |
|     RUBY_MARK_ENTER("cont");
 | |
|     rb_gc_mark_movable(cont->value);
 | |
| 
 | |
|     rb_execution_context_mark(&cont->saved_ec);
 | |
|     rb_gc_mark(cont_thread_value(cont));
 | |
| 
 | |
|     if (cont->saved_vm_stack.ptr) {
 | |
| #ifdef CAPTURE_JUST_VALID_VM_STACK
 | |
|         rb_gc_mark_locations(cont->saved_vm_stack.ptr,
 | |
|                              cont->saved_vm_stack.ptr + cont->saved_vm_stack.slen + cont->saved_vm_stack.clen);
 | |
| #else
 | |
|         rb_gc_mark_locations(cont->saved_vm_stack.ptr,
 | |
|                              cont->saved_vm_stack.ptr, cont->saved_ec.stack_size);
 | |
| #endif
 | |
|     }
 | |
| 
 | |
|     if (cont->machine.stack) {
 | |
|         if (cont->type == CONTINUATION_CONTEXT) {
 | |
|             /* cont */
 | |
|             rb_gc_mark_locations(cont->machine.stack,
 | |
|                                  cont->machine.stack + cont->machine.stack_size);
 | |
|         }
 | |
|         else {
 | |
|             /* fiber */
 | |
|             const rb_fiber_t *fiber = (rb_fiber_t*)cont;
 | |
| 
 | |
|             if (!FIBER_TERMINATED_P(fiber)) {
 | |
|                 rb_gc_mark_locations(cont->machine.stack,
 | |
|                                      cont->machine.stack + cont->machine.stack_size);
 | |
|             }
 | |
|         }
 | |
|     }
 | |
| 
 | |
|     RUBY_MARK_LEAVE("cont");
 | |
| }
 | |
| 
 | |
| static int
 | |
| fiber_is_root_p(const rb_fiber_t *fiber)
 | |
| {
 | |
|     return fiber == fiber->cont.saved_ec.thread_ptr->root_fiber;
 | |
| }
 | |
| 
 | |
| static void
 | |
| cont_free(void *ptr)
 | |
| {
 | |
|     rb_context_t *cont = ptr;
 | |
| 
 | |
|     RUBY_FREE_ENTER("cont");
 | |
| 
 | |
|     if (cont->type == CONTINUATION_CONTEXT) {
 | |
|         ruby_xfree(cont->saved_ec.vm_stack);
 | |
|         ruby_xfree(cont->ensure_array);
 | |
|         RUBY_FREE_UNLESS_NULL(cont->machine.stack);
 | |
|     }
 | |
|     else {
 | |
|         rb_fiber_t *fiber = (rb_fiber_t*)cont;
 | |
|         coroutine_destroy(&fiber->context);
 | |
|         if (!fiber_is_root_p(fiber)) {
 | |
|             fiber_stack_release(fiber);
 | |
|         }
 | |
|     }
 | |
| 
 | |
|     RUBY_FREE_UNLESS_NULL(cont->saved_vm_stack.ptr);
 | |
| 
 | |
|     if (mjit_enabled && cont->mjit_cont != NULL) {
 | |
|         mjit_cont_free(cont->mjit_cont);
 | |
|     }
 | |
|     /* free rb_cont_t or rb_fiber_t */
 | |
|     ruby_xfree(ptr);
 | |
|     RUBY_FREE_LEAVE("cont");
 | |
| }
 | |
| 
 | |
| static size_t
 | |
| cont_memsize(const void *ptr)
 | |
| {
 | |
|     const rb_context_t *cont = ptr;
 | |
|     size_t size = 0;
 | |
| 
 | |
|     size = sizeof(*cont);
 | |
|     if (cont->saved_vm_stack.ptr) {
 | |
| #ifdef CAPTURE_JUST_VALID_VM_STACK
 | |
|         size_t n = (cont->saved_vm_stack.slen + cont->saved_vm_stack.clen);
 | |
| #else
 | |
|         size_t n = cont->saved_ec.vm_stack_size;
 | |
| #endif
 | |
|         size += n * sizeof(*cont->saved_vm_stack.ptr);
 | |
|     }
 | |
| 
 | |
|     if (cont->machine.stack) {
 | |
|         size += cont->machine.stack_size * sizeof(*cont->machine.stack);
 | |
|     }
 | |
| 
 | |
|     return size;
 | |
| }
 | |
| 
 | |
| void
 | |
| rb_fiber_update_self(rb_fiber_t *fiber)
 | |
| {
 | |
|     if (fiber->cont.self) {
 | |
|         fiber->cont.self = rb_gc_location(fiber->cont.self);
 | |
|     }
 | |
|     else {
 | |
|         rb_execution_context_update(&fiber->cont.saved_ec);
 | |
|     }
 | |
| }
 | |
| 
 | |
| void
 | |
| rb_fiber_mark_self(const rb_fiber_t *fiber)
 | |
| {
 | |
|     if (fiber->cont.self) {
 | |
|         rb_gc_mark_movable(fiber->cont.self);
 | |
|     }
 | |
|     else {
 | |
|         rb_execution_context_mark(&fiber->cont.saved_ec);
 | |
|     }
 | |
| }
 | |
| 
 | |
| static void
 | |
| fiber_compact(void *ptr)
 | |
| {
 | |
|     rb_fiber_t *fiber = ptr;
 | |
|     fiber->first_proc = rb_gc_location(fiber->first_proc);
 | |
| 
 | |
|     if (fiber->prev) rb_fiber_update_self(fiber->prev);
 | |
| 
 | |
|     cont_compact(&fiber->cont);
 | |
|     fiber_verify(fiber);
 | |
| }
 | |
| 
 | |
| static void
 | |
| fiber_mark(void *ptr)
 | |
| {
 | |
|     rb_fiber_t *fiber = ptr;
 | |
|     RUBY_MARK_ENTER("cont");
 | |
|     fiber_verify(fiber);
 | |
|     rb_gc_mark_movable(fiber->first_proc);
 | |
|     if (fiber->prev) rb_fiber_mark_self(fiber->prev);
 | |
|     cont_mark(&fiber->cont);
 | |
|     RUBY_MARK_LEAVE("cont");
 | |
| }
 | |
| 
 | |
| static void
 | |
| fiber_free(void *ptr)
 | |
| {
 | |
|     rb_fiber_t *fiber = ptr;
 | |
|     RUBY_FREE_ENTER("fiber");
 | |
| 
 | |
|     //if (DEBUG) fprintf(stderr, "fiber_free: %p[%p]\n", fiber, fiber->stack.base);
 | |
| 
 | |
|     if (fiber->cont.saved_ec.local_storage) {
 | |
|         st_free_table(fiber->cont.saved_ec.local_storage);
 | |
|     }
 | |
| 
 | |
|     cont_free(&fiber->cont);
 | |
|     RUBY_FREE_LEAVE("fiber");
 | |
| }
 | |
| 
 | |
| static size_t
 | |
| fiber_memsize(const void *ptr)
 | |
| {
 | |
|     const rb_fiber_t *fiber = ptr;
 | |
|     size_t size = sizeof(*fiber);
 | |
|     const rb_execution_context_t *saved_ec = &fiber->cont.saved_ec;
 | |
|     const rb_thread_t *th = rb_ec_thread_ptr(saved_ec);
 | |
| 
 | |
|     /*
 | |
|      * vm.c::thread_memsize already counts th->ec->local_storage
 | |
|      */
 | |
|     if (saved_ec->local_storage && fiber != th->root_fiber) {
 | |
|         size += st_memsize(saved_ec->local_storage);
 | |
|     }
 | |
|     size += cont_memsize(&fiber->cont);
 | |
|     return size;
 | |
| }
 | |
| 
 | |
| VALUE
 | |
| rb_obj_is_fiber(VALUE obj)
 | |
| {
 | |
|     if (rb_typeddata_is_kind_of(obj, &fiber_data_type)) {
 | |
|         return Qtrue;
 | |
|     }
 | |
|     else {
 | |
|         return Qfalse;
 | |
|     }
 | |
| }
 | |
| 
 | |
| static void
 | |
| cont_save_machine_stack(rb_thread_t *th, rb_context_t *cont)
 | |
| {
 | |
|     size_t size;
 | |
| 
 | |
|     SET_MACHINE_STACK_END(&th->ec->machine.stack_end);
 | |
| 
 | |
|     if (th->ec->machine.stack_start > th->ec->machine.stack_end) {
 | |
|         size = cont->machine.stack_size = th->ec->machine.stack_start - th->ec->machine.stack_end;
 | |
|         cont->machine.stack_src = th->ec->machine.stack_end;
 | |
|     }
 | |
|     else {
 | |
|         size = cont->machine.stack_size = th->ec->machine.stack_end - th->ec->machine.stack_start;
 | |
|         cont->machine.stack_src = th->ec->machine.stack_start;
 | |
|     }
 | |
| 
 | |
|     if (cont->machine.stack) {
 | |
|         REALLOC_N(cont->machine.stack, VALUE, size);
 | |
|     }
 | |
|     else {
 | |
|         cont->machine.stack = ALLOC_N(VALUE, size);
 | |
|     }
 | |
| 
 | |
|     FLUSH_REGISTER_WINDOWS;
 | |
|     MEMCPY(cont->machine.stack, cont->machine.stack_src, VALUE, size);
 | |
| }
 | |
| 
 | |
| static const rb_data_type_t cont_data_type = {
 | |
|     "continuation",
 | |
|     {cont_mark, cont_free, cont_memsize, cont_compact},
 | |
|     0, 0, RUBY_TYPED_FREE_IMMEDIATELY
 | |
| };
 | |
| 
 | |
| static inline void
 | |
| cont_save_thread(rb_context_t *cont, rb_thread_t *th)
 | |
| {
 | |
|     rb_execution_context_t *sec = &cont->saved_ec;
 | |
| 
 | |
|     VM_ASSERT(th->status == THREAD_RUNNABLE);
 | |
| 
 | |
|     /* save thread context */
 | |
|     *sec = *th->ec;
 | |
| 
 | |
|     /* saved_ec->machine.stack_end should be NULL */
 | |
|     /* because it may happen GC afterward */
 | |
|     sec->machine.stack_end = NULL;
 | |
| }
 | |
| 
 | |
| static void
 | |
| cont_init(rb_context_t *cont, rb_thread_t *th)
 | |
| {
 | |
|     /* save thread context */
 | |
|     cont_save_thread(cont, th);
 | |
|     cont->saved_ec.thread_ptr = th;
 | |
|     cont->saved_ec.local_storage = NULL;
 | |
|     cont->saved_ec.local_storage_recursive_hash = Qnil;
 | |
|     cont->saved_ec.local_storage_recursive_hash_for_trace = Qnil;
 | |
|     if (mjit_enabled) {
 | |
|         cont->mjit_cont = mjit_cont_new(&cont->saved_ec);
 | |
|     }
 | |
| }
 | |
| 
 | |
| static rb_context_t *
 | |
| cont_new(VALUE klass)
 | |
| {
 | |
|     rb_context_t *cont;
 | |
|     volatile VALUE contval;
 | |
|     rb_thread_t *th = GET_THREAD();
 | |
| 
 | |
|     THREAD_MUST_BE_RUNNING(th);
 | |
|     contval = TypedData_Make_Struct(klass, rb_context_t, &cont_data_type, cont);
 | |
|     cont->self = contval;
 | |
|     cont_init(cont, th);
 | |
|     return cont;
 | |
| }
 | |
| 
 | |
| #if 0
 | |
| void
 | |
| show_vm_stack(const rb_execution_context_t *ec)
 | |
| {
 | |
|     VALUE *p = ec->vm_stack;
 | |
|     while (p < ec->cfp->sp) {
 | |
|         fprintf(stderr, "%3d ", (int)(p - ec->vm_stack));
 | |
|         rb_obj_info_dump(*p);
 | |
|         p++;
 | |
|     }
 | |
| }
 | |
| 
 | |
| void
 | |
| show_vm_pcs(const rb_control_frame_t *cfp,
 | |
|             const rb_control_frame_t *end_of_cfp)
 | |
| {
 | |
|     int i=0;
 | |
|     while (cfp != end_of_cfp) {
 | |
|         int pc = 0;
 | |
|         if (cfp->iseq) {
 | |
|             pc = cfp->pc - cfp->iseq->body->iseq_encoded;
 | |
|         }
 | |
|         fprintf(stderr, "%2d pc: %d\n", i++, pc);
 | |
|         cfp = RUBY_VM_PREVIOUS_CONTROL_FRAME(cfp);
 | |
|     }
 | |
| }
 | |
| #endif
 | |
| COMPILER_WARNING_PUSH
 | |
| #ifdef __clang__
 | |
| COMPILER_WARNING_IGNORED(-Wduplicate-decl-specifier)
 | |
| #endif
 | |
| static VALUE
 | |
| cont_capture(volatile int *volatile stat)
 | |
| {
 | |
|     rb_context_t *volatile cont;
 | |
|     rb_thread_t *th = GET_THREAD();
 | |
|     volatile VALUE contval;
 | |
|     const rb_execution_context_t *ec = th->ec;
 | |
| 
 | |
|     THREAD_MUST_BE_RUNNING(th);
 | |
|     rb_vm_stack_to_heap(th->ec);
 | |
|     cont = cont_new(rb_cContinuation);
 | |
|     contval = cont->self;
 | |
| 
 | |
| #ifdef CAPTURE_JUST_VALID_VM_STACK
 | |
|     cont->saved_vm_stack.slen = ec->cfp->sp - ec->vm_stack;
 | |
|     cont->saved_vm_stack.clen = ec->vm_stack + ec->vm_stack_size - (VALUE*)ec->cfp;
 | |
|     cont->saved_vm_stack.ptr = ALLOC_N(VALUE, cont->saved_vm_stack.slen + cont->saved_vm_stack.clen);
 | |
|     MEMCPY(cont->saved_vm_stack.ptr,
 | |
|            ec->vm_stack,
 | |
|            VALUE, cont->saved_vm_stack.slen);
 | |
|     MEMCPY(cont->saved_vm_stack.ptr + cont->saved_vm_stack.slen,
 | |
|            (VALUE*)ec->cfp,
 | |
|            VALUE,
 | |
|            cont->saved_vm_stack.clen);
 | |
| #else
 | |
|     cont->saved_vm_stack.ptr = ALLOC_N(VALUE, ec->vm_stack_size);
 | |
|     MEMCPY(cont->saved_vm_stack.ptr, ec->vm_stack, VALUE, ec->vm_stack_size);
 | |
| #endif
 | |
|     // At this point, `cfp` is valid but `vm_stack` should be cleared:
 | |
|     rb_ec_set_vm_stack(&cont->saved_ec, NULL, 0);
 | |
|     VM_ASSERT(cont->saved_ec.cfp != NULL);
 | |
|     cont_save_machine_stack(th, cont);
 | |
| 
 | |
|     /* backup ensure_list to array for search in another context */
 | |
|     {
 | |
|         rb_ensure_list_t *p;
 | |
|         int size = 0;
 | |
|         rb_ensure_entry_t *entry;
 | |
|         for (p=th->ec->ensure_list; p; p=p->next)
 | |
|             size++;
 | |
|         entry = cont->ensure_array = ALLOC_N(rb_ensure_entry_t,size+1);
 | |
|         for (p=th->ec->ensure_list; p; p=p->next) {
 | |
|             if (!p->entry.marker)
 | |
|                 p->entry.marker = rb_ary_tmp_new(0); /* dummy object */
 | |
|             *entry++ = p->entry;
 | |
|         }
 | |
|         entry->marker = 0;
 | |
|     }
 | |
| 
 | |
|     if (ruby_setjmp(cont->jmpbuf)) {
 | |
|         VALUE value;
 | |
| 
 | |
|         VAR_INITIALIZED(cont);
 | |
|         value = cont->value;
 | |
|         if (cont->argc == -1) rb_exc_raise(value);
 | |
|         cont->value = Qnil;
 | |
|         *stat = 1;
 | |
|         return value;
 | |
|     }
 | |
|     else {
 | |
|         *stat = 0;
 | |
|         return contval;
 | |
|     }
 | |
| }
 | |
| COMPILER_WARNING_POP
 | |
| 
 | |
| static inline void
 | |
| fiber_restore_thread(rb_thread_t *th, rb_fiber_t *fiber)
 | |
| {
 | |
|     ec_switch(th, fiber);
 | |
|     VM_ASSERT(th->ec->fiber_ptr == fiber);
 | |
| }
 | |
| 
 | |
| static inline void
 | |
| cont_restore_thread(rb_context_t *cont)
 | |
| {
 | |
|     rb_thread_t *th = GET_THREAD();
 | |
| 
 | |
|     /* restore thread context */
 | |
|     if (cont->type == CONTINUATION_CONTEXT) {
 | |
|         /* continuation */
 | |
|         rb_execution_context_t *sec = &cont->saved_ec;
 | |
|         rb_fiber_t *fiber = NULL;
 | |
| 
 | |
|         if (sec->fiber_ptr != NULL) {
 | |
|             fiber = sec->fiber_ptr;
 | |
|         }
 | |
|         else if (th->root_fiber) {
 | |
|             fiber = th->root_fiber;
 | |
|         }
 | |
| 
 | |
|         if (fiber && th->ec != &fiber->cont.saved_ec) {
 | |
|             ec_switch(th, fiber);
 | |
|         }
 | |
| 
 | |
|         if (th->ec->trace_arg != sec->trace_arg) {
 | |
|             rb_raise(rb_eRuntimeError, "can't call across trace_func");
 | |
|         }
 | |
| 
 | |
|         /* copy vm stack */
 | |
| #ifdef CAPTURE_JUST_VALID_VM_STACK
 | |
|         MEMCPY(th->ec->vm_stack,
 | |
|                cont->saved_vm_stack.ptr,
 | |
|                VALUE, cont->saved_vm_stack.slen);
 | |
|         MEMCPY(th->ec->vm_stack + th->ec->vm_stack_size - cont->saved_vm_stack.clen,
 | |
|                cont->saved_vm_stack.ptr + cont->saved_vm_stack.slen,
 | |
|                VALUE, cont->saved_vm_stack.clen);
 | |
| #else
 | |
|         MEMCPY(th->ec->vm_stack, cont->saved_vm_stack.ptr, VALUE, sec->vm_stack_size);
 | |
| #endif
 | |
|         /* other members of ec */
 | |
| 
 | |
|         th->ec->cfp = sec->cfp;
 | |
|         th->ec->raised_flag = sec->raised_flag;
 | |
|         th->ec->tag = sec->tag;
 | |
|         th->ec->protect_tag = sec->protect_tag;
 | |
|         th->ec->root_lep = sec->root_lep;
 | |
|         th->ec->root_svar = sec->root_svar;
 | |
|         th->ec->ensure_list = sec->ensure_list;
 | |
|         th->ec->errinfo = sec->errinfo;
 | |
| 
 | |
|         VM_ASSERT(th->ec->vm_stack != NULL);
 | |
|     }
 | |
|     else {
 | |
|         /* fiber */
 | |
|         fiber_restore_thread(th, (rb_fiber_t*)cont);
 | |
|     }
 | |
| }
 | |
| 
 | |
| NOINLINE(static void fiber_setcontext(rb_fiber_t *new_fiber, rb_fiber_t *old_fiber));
 | |
| 
 | |
| static void
 | |
| fiber_setcontext(rb_fiber_t *new_fiber, rb_fiber_t *old_fiber)
 | |
| {
 | |
|     rb_thread_t *th = GET_THREAD();
 | |
| 
 | |
|     /* save old_fiber's machine stack - to ensure efficient garbage collection */
 | |
|     if (!FIBER_TERMINATED_P(old_fiber)) {
 | |
|         STACK_GROW_DIR_DETECTION;
 | |
|         SET_MACHINE_STACK_END(&th->ec->machine.stack_end);
 | |
|         if (STACK_DIR_UPPER(0, 1)) {
 | |
|             old_fiber->cont.machine.stack_size = th->ec->machine.stack_start - th->ec->machine.stack_end;
 | |
|             old_fiber->cont.machine.stack = th->ec->machine.stack_end;
 | |
|         }
 | |
|         else {
 | |
|             old_fiber->cont.machine.stack_size = th->ec->machine.stack_end - th->ec->machine.stack_start;
 | |
|             old_fiber->cont.machine.stack = th->ec->machine.stack_start;
 | |
|         }
 | |
|     }
 | |
| 
 | |
|     /* exchange machine_stack_start between old_fiber and new_fiber */
 | |
|     old_fiber->cont.saved_ec.machine.stack_start = th->ec->machine.stack_start;
 | |
| 
 | |
|     /* old_fiber->machine.stack_end should be NULL */
 | |
|     old_fiber->cont.saved_ec.machine.stack_end = NULL;
 | |
| 
 | |
|     /* restore thread context */
 | |
|     fiber_restore_thread(th, new_fiber);
 | |
| 
 | |
|     // if (DEBUG) fprintf(stderr, "fiber_setcontext: %p[%p] -> %p[%p]\n", old_fiber, old_fiber->stack.base, new_fiber, new_fiber->stack.base);
 | |
| 
 | |
|     /* swap machine context */
 | |
|     coroutine_transfer(&old_fiber->context, &new_fiber->context);
 | |
| 
 | |
|     // It's possible to get here, and new_fiber is already freed.
 | |
|     // if (DEBUG) fprintf(stderr, "fiber_setcontext: %p[%p] <- %p[%p]\n", old_fiber, old_fiber->stack.base, new_fiber, new_fiber->stack.base);
 | |
| }
 | |
| 
 | |
| NOINLINE(NORETURN(static void cont_restore_1(rb_context_t *)));
 | |
| 
 | |
| static void
 | |
| cont_restore_1(rb_context_t *cont)
 | |
| {
 | |
|     cont_restore_thread(cont);
 | |
| 
 | |
|     /* restore machine stack */
 | |
| #ifdef _M_AMD64
 | |
|     {
 | |
|         /* workaround for x64 SEH */
 | |
|         jmp_buf buf;
 | |
|         setjmp(buf);
 | |
|         ((_JUMP_BUFFER*)(&cont->jmpbuf))->Frame =
 | |
|             ((_JUMP_BUFFER*)(&buf))->Frame;
 | |
|     }
 | |
| #endif
 | |
|     if (cont->machine.stack_src) {
 | |
|         FLUSH_REGISTER_WINDOWS;
 | |
|         MEMCPY(cont->machine.stack_src, cont->machine.stack,
 | |
|                VALUE, cont->machine.stack_size);
 | |
|     }
 | |
| 
 | |
|     ruby_longjmp(cont->jmpbuf, 1);
 | |
| }
 | |
| 
 | |
| NORETURN(NOINLINE(static void cont_restore_0(rb_context_t *, VALUE *)));
 | |
| 
 | |
| static void
 | |
| cont_restore_0(rb_context_t *cont, VALUE *addr_in_prev_frame)
 | |
| {
 | |
|     if (cont->machine.stack_src) {
 | |
| #ifdef HAVE_ALLOCA
 | |
| #define STACK_PAD_SIZE 1
 | |
| #else
 | |
| #define STACK_PAD_SIZE 1024
 | |
| #endif
 | |
|         VALUE space[STACK_PAD_SIZE];
 | |
| 
 | |
| #if !STACK_GROW_DIRECTION
 | |
|         if (addr_in_prev_frame > &space[0]) {
 | |
|             /* Stack grows downward */
 | |
| #endif
 | |
| #if STACK_GROW_DIRECTION <= 0
 | |
|             volatile VALUE *const end = cont->machine.stack_src;
 | |
|             if (&space[0] > end) {
 | |
| # ifdef HAVE_ALLOCA
 | |
|                 volatile VALUE *sp = ALLOCA_N(VALUE, &space[0] - end);
 | |
|                 space[0] = *sp;
 | |
| # else
 | |
|                 cont_restore_0(cont, &space[0]);
 | |
| # endif
 | |
|             }
 | |
| #endif
 | |
| #if !STACK_GROW_DIRECTION
 | |
|         }
 | |
|         else {
 | |
|             /* Stack grows upward */
 | |
| #endif
 | |
| #if STACK_GROW_DIRECTION >= 0
 | |
|             volatile VALUE *const end = cont->machine.stack_src + cont->machine.stack_size;
 | |
|             if (&space[STACK_PAD_SIZE] < end) {
 | |
| # ifdef HAVE_ALLOCA
 | |
|                 volatile VALUE *sp = ALLOCA_N(VALUE, end - &space[STACK_PAD_SIZE]);
 | |
|                 space[0] = *sp;
 | |
| # else
 | |
|                 cont_restore_0(cont, &space[STACK_PAD_SIZE-1]);
 | |
| # endif
 | |
|             }
 | |
| #endif
 | |
| #if !STACK_GROW_DIRECTION
 | |
|         }
 | |
| #endif
 | |
|     }
 | |
|     cont_restore_1(cont);
 | |
| }
 | |
| 
 | |
| /*
 | |
|  *  Document-class: Continuation
 | |
|  *
 | |
|  *  Continuation objects are generated by Kernel#callcc,
 | |
|  *  after having +require+d <i>continuation</i>. They hold
 | |
|  *  a return address and execution context, allowing a nonlocal return
 | |
|  *  to the end of the #callcc block from anywhere within a
 | |
|  *  program. Continuations are somewhat analogous to a structured
 | |
|  *  version of C's <code>setjmp/longjmp</code> (although they contain
 | |
|  *  more state, so you might consider them closer to threads).
 | |
|  *
 | |
|  *  For instance:
 | |
|  *
 | |
|  *     require "continuation"
 | |
|  *     arr = [ "Freddie", "Herbie", "Ron", "Max", "Ringo" ]
 | |
|  *     callcc{|cc| $cc = cc}
 | |
|  *     puts(message = arr.shift)
 | |
|  *     $cc.call unless message =~ /Max/
 | |
|  *
 | |
|  *  <em>produces:</em>
 | |
|  *
 | |
|  *     Freddie
 | |
|  *     Herbie
 | |
|  *     Ron
 | |
|  *     Max
 | |
|  *
 | |
|  *  Also you can call callcc in other methods:
 | |
|  *
 | |
|  *     require "continuation"
 | |
|  *
 | |
|  *     def g
 | |
|  *       arr = [ "Freddie", "Herbie", "Ron", "Max", "Ringo" ]
 | |
|  *       cc = callcc { |cc| cc }
 | |
|  *       puts arr.shift
 | |
|  *       return cc, arr.size
 | |
|  *     end
 | |
|  *
 | |
|  *     def f
 | |
|  *       c, size = g
 | |
|  *       c.call(c) if size > 1
 | |
|  *     end
 | |
|  *
 | |
|  *     f
 | |
|  *
 | |
|  *  This (somewhat contrived) example allows the inner loop to abandon
 | |
|  *  processing early:
 | |
|  *
 | |
|  *     require "continuation"
 | |
|  *     callcc {|cont|
 | |
|  *       for i in 0..4
 | |
|  *         print "#{i}: "
 | |
|  *         for j in i*5...(i+1)*5
 | |
|  *           cont.call() if j == 17
 | |
|  *           printf "%3d", j
 | |
|  *         end
 | |
|  *       end
 | |
|  *     }
 | |
|  *     puts
 | |
|  *
 | |
|  *  <em>produces:</em>
 | |
|  *
 | |
|  *     0:   0  1  2  3  4
 | |
|  *     1:   5  6  7  8  9
 | |
|  *     2:  10 11 12 13 14
 | |
|  *     3:  15 16
 | |
|  */
 | |
| 
 | |
| /*
 | |
|  *  call-seq:
 | |
|  *     callcc {|cont| block }   ->  obj
 | |
|  *
 | |
|  *  Generates a Continuation object, which it passes to
 | |
|  *  the associated block. You need to <code>require
 | |
|  *  'continuation'</code> before using this method. Performing a
 | |
|  *  <em>cont</em><code>.call</code> will cause the #callcc
 | |
|  *  to return (as will falling through the end of the block). The
 | |
|  *  value returned by the #callcc is the value of the
 | |
|  *  block, or the value passed to <em>cont</em><code>.call</code>. See
 | |
|  *  class Continuation for more details. Also see
 | |
|  *  Kernel#throw for an alternative mechanism for
 | |
|  *  unwinding a call stack.
 | |
|  */
 | |
| 
 | |
| static VALUE
 | |
| rb_callcc(VALUE self)
 | |
| {
 | |
|     volatile int called;
 | |
|     volatile VALUE val = cont_capture(&called);
 | |
| 
 | |
|     if (called) {
 | |
|         return val;
 | |
|     }
 | |
|     else {
 | |
|         return rb_yield(val);
 | |
|     }
 | |
| }
 | |
| 
 | |
| static VALUE
 | |
| make_passing_arg(int argc, const VALUE *argv)
 | |
| {
 | |
|     switch (argc) {
 | |
|       case -1:
 | |
|         return argv[0];
 | |
|       case 0:
 | |
|         return Qnil;
 | |
|       case 1:
 | |
|         return argv[0];
 | |
|       default:
 | |
|         return rb_ary_new4(argc, argv);
 | |
|     }
 | |
| }
 | |
| 
 | |
| /* CAUTION!! : Currently, error in rollback_func is not supported  */
 | |
| /* same as rb_protect if set rollback_func to NULL */
 | |
| void
 | |
| ruby_register_rollback_func_for_ensure(VALUE (*ensure_func)(ANYARGS), VALUE (*rollback_func)(ANYARGS))
 | |
| {
 | |
|     st_table **table_p = &GET_VM()->ensure_rollback_table;
 | |
|     if (UNLIKELY(*table_p == NULL)) {
 | |
|         *table_p = st_init_numtable();
 | |
|     }
 | |
|     st_insert(*table_p, (st_data_t)ensure_func, (st_data_t)rollback_func);
 | |
| }
 | |
| 
 | |
| static inline VALUE
 | |
| lookup_rollback_func(VALUE (*ensure_func)(ANYARGS))
 | |
| {
 | |
|     st_table *table = GET_VM()->ensure_rollback_table;
 | |
|     st_data_t val;
 | |
|     if (table && st_lookup(table, (st_data_t)ensure_func, &val))
 | |
|         return (VALUE) val;
 | |
|     return Qundef;
 | |
| }
 | |
| 
 | |
| 
 | |
| static inline void
 | |
| rollback_ensure_stack(VALUE self,rb_ensure_list_t *current,rb_ensure_entry_t *target)
 | |
| {
 | |
|     rb_ensure_list_t *p;
 | |
|     rb_ensure_entry_t *entry;
 | |
|     size_t i, j;
 | |
|     size_t cur_size;
 | |
|     size_t target_size;
 | |
|     size_t base_point;
 | |
|     VALUE (*func)(ANYARGS);
 | |
| 
 | |
|     cur_size = 0;
 | |
|     for (p=current; p; p=p->next)
 | |
|         cur_size++;
 | |
|     target_size = 0;
 | |
|     for (entry=target; entry->marker; entry++)
 | |
|         target_size++;
 | |
| 
 | |
|     /* search common stack point */
 | |
|     p = current;
 | |
|     base_point = cur_size;
 | |
|     while (base_point) {
 | |
|         if (target_size >= base_point &&
 | |
|             p->entry.marker == target[target_size - base_point].marker)
 | |
|             break;
 | |
|         base_point --;
 | |
|         p = p->next;
 | |
|     }
 | |
| 
 | |
|     /* rollback function check */
 | |
|     for (i=0; i < target_size - base_point; i++) {
 | |
|         if (!lookup_rollback_func(target[i].e_proc)) {
 | |
|             rb_raise(rb_eRuntimeError, "continuation called from out of critical rb_ensure scope");
 | |
|         }
 | |
|     }
 | |
|     /* pop ensure stack */
 | |
|     while (cur_size > base_point) {
 | |
|         /* escape from ensure block */
 | |
|         (*current->entry.e_proc)(current->entry.data2);
 | |
|         current = current->next;
 | |
|         cur_size--;
 | |
|     }
 | |
|     /* push ensure stack */
 | |
|     for (j = 0; j < i; j++) {
 | |
|         func = (VALUE (*)(ANYARGS)) lookup_rollback_func(target[i - j - 1].e_proc);
 | |
|         if ((VALUE)func != Qundef) {
 | |
|             (*func)(target[i - j - 1].data2);
 | |
|         }
 | |
|     }
 | |
| }
 | |
| 
 | |
| /*
 | |
|  *  call-seq:
 | |
|  *     cont.call(args, ...)
 | |
|  *     cont[args, ...]
 | |
|  *
 | |
|  *  Invokes the continuation. The program continues from the end of
 | |
|  *  the #callcc block. If no arguments are given, the original #callcc
 | |
|  *  returns +nil+. If one argument is given, #callcc returns
 | |
|  *  it. Otherwise, an array containing <i>args</i> is returned.
 | |
|  *
 | |
|  *     callcc {|cont|  cont.call }           #=> nil
 | |
|  *     callcc {|cont|  cont.call 1 }         #=> 1
 | |
|  *     callcc {|cont|  cont.call 1, 2, 3 }   #=> [1, 2, 3]
 | |
|  */
 | |
| 
 | |
| static VALUE
 | |
| rb_cont_call(int argc, VALUE *argv, VALUE contval)
 | |
| {
 | |
|     rb_context_t *cont = cont_ptr(contval);
 | |
|     rb_thread_t *th = GET_THREAD();
 | |
| 
 | |
|     if (cont_thread_value(cont) != th->self) {
 | |
|         rb_raise(rb_eRuntimeError, "continuation called across threads");
 | |
|     }
 | |
|     if (cont->saved_ec.protect_tag != th->ec->protect_tag) {
 | |
|         rb_raise(rb_eRuntimeError, "continuation called across stack rewinding barrier");
 | |
|     }
 | |
|     if (cont->saved_ec.fiber_ptr) {
 | |
|         if (th->ec->fiber_ptr != cont->saved_ec.fiber_ptr) {
 | |
|             rb_raise(rb_eRuntimeError, "continuation called across fiber");
 | |
|         }
 | |
|     }
 | |
|     rollback_ensure_stack(contval, th->ec->ensure_list, cont->ensure_array);
 | |
| 
 | |
|     cont->argc = argc;
 | |
|     cont->value = make_passing_arg(argc, argv);
 | |
| 
 | |
|     cont_restore_0(cont, &contval);
 | |
|     return Qnil; /* unreachable */
 | |
| }
 | |
| 
 | |
| /*********/
 | |
| /* fiber */
 | |
| /*********/
 | |
| 
 | |
| /*
 | |
|  *  Document-class: Fiber
 | |
|  *
 | |
|  *  Fibers are primitives for implementing light weight cooperative
 | |
|  *  concurrency in Ruby. Basically they are a means of creating code blocks
 | |
|  *  that can be paused and resumed, much like threads. The main difference
 | |
|  *  is that they are never preempted and that the scheduling must be done by
 | |
|  *  the programmer and not the VM.
 | |
|  *
 | |
|  *  As opposed to other stackless light weight concurrency models, each fiber
 | |
|  *  comes with a stack.  This enables the fiber to be paused from deeply
 | |
|  *  nested function calls within the fiber block.  See the ruby(1)
 | |
|  *  manpage to configure the size of the fiber stack(s).
 | |
|  *
 | |
|  *  When a fiber is created it will not run automatically. Rather it must
 | |
|  *  be explicitly asked to run using the Fiber#resume method.
 | |
|  *  The code running inside the fiber can give up control by calling
 | |
|  *  Fiber.yield in which case it yields control back to caller (the
 | |
|  *  caller of the Fiber#resume).
 | |
|  *
 | |
|  *  Upon yielding or termination the Fiber returns the value of the last
 | |
|  *  executed expression
 | |
|  *
 | |
|  *  For instance:
 | |
|  *
 | |
|  *    fiber = Fiber.new do
 | |
|  *      Fiber.yield 1
 | |
|  *      2
 | |
|  *    end
 | |
|  *
 | |
|  *    puts fiber.resume
 | |
|  *    puts fiber.resume
 | |
|  *    puts fiber.resume
 | |
|  *
 | |
|  *  <em>produces</em>
 | |
|  *
 | |
|  *    1
 | |
|  *    2
 | |
|  *    FiberError: dead fiber called
 | |
|  *
 | |
|  *  The Fiber#resume method accepts an arbitrary number of parameters,
 | |
|  *  if it is the first call to #resume then they will be passed as
 | |
|  *  block arguments. Otherwise they will be the return value of the
 | |
|  *  call to Fiber.yield
 | |
|  *
 | |
|  *  Example:
 | |
|  *
 | |
|  *    fiber = Fiber.new do |first|
 | |
|  *      second = Fiber.yield first + 2
 | |
|  *    end
 | |
|  *
 | |
|  *    puts fiber.resume 10
 | |
|  *    puts fiber.resume 1_000_000
 | |
|  *    puts fiber.resume "The fiber will be dead before I can cause trouble"
 | |
|  *
 | |
|  *  <em>produces</em>
 | |
|  *
 | |
|  *    12
 | |
|  *    1000000
 | |
|  *    FiberError: dead fiber called
 | |
|  *
 | |
|  */
 | |
| 
 | |
| static const rb_data_type_t fiber_data_type = {
 | |
|     "fiber",
 | |
|     {fiber_mark, fiber_free, fiber_memsize, fiber_compact,},
 | |
|     0, 0, RUBY_TYPED_FREE_IMMEDIATELY
 | |
| };
 | |
| 
 | |
| static VALUE
 | |
| fiber_alloc(VALUE klass)
 | |
| {
 | |
|     return TypedData_Wrap_Struct(klass, &fiber_data_type, 0);
 | |
| }
 | |
| 
 | |
| static rb_fiber_t*
 | |
| fiber_t_alloc(VALUE fiber_value)
 | |
| {
 | |
|     rb_fiber_t *fiber;
 | |
|     rb_thread_t *th = GET_THREAD();
 | |
| 
 | |
|     if (DATA_PTR(fiber_value) != 0) {
 | |
|         rb_raise(rb_eRuntimeError, "cannot initialize twice");
 | |
|     }
 | |
| 
 | |
|     THREAD_MUST_BE_RUNNING(th);
 | |
|     fiber = ZALLOC(rb_fiber_t);
 | |
|     fiber->cont.self = fiber_value;
 | |
|     fiber->cont.type = FIBER_CONTEXT;
 | |
|     cont_init(&fiber->cont, th);
 | |
| 
 | |
|     fiber->cont.saved_ec.fiber_ptr = fiber;
 | |
|     rb_ec_clear_vm_stack(&fiber->cont.saved_ec);
 | |
| 
 | |
|     fiber->prev = NULL;
 | |
| 
 | |
|     /* fiber->status == 0 == CREATED
 | |
|      * So that we don't need to set status: fiber_status_set(fiber, FIBER_CREATED); */
 | |
|     VM_ASSERT(FIBER_CREATED_P(fiber));
 | |
| 
 | |
|     DATA_PTR(fiber_value) = fiber;
 | |
| 
 | |
|     return fiber;
 | |
| }
 | |
| 
 | |
| static VALUE
 | |
| fiber_initialize(VALUE self, VALUE proc, struct fiber_pool * fiber_pool)
 | |
| {
 | |
|     rb_fiber_t *fiber = fiber_t_alloc(self);
 | |
| 
 | |
|     fiber->first_proc = proc;
 | |
|     fiber->stack.base = NULL;
 | |
|     fiber->stack.pool = fiber_pool;
 | |
| 
 | |
|     return self;
 | |
| }
 | |
| 
 | |
| static void
 | |
| fiber_prepare_stack(rb_fiber_t *fiber)
 | |
| {
 | |
|     rb_context_t *cont = &fiber->cont;
 | |
|     rb_execution_context_t *sec = &cont->saved_ec;
 | |
| 
 | |
|     size_t vm_stack_size = 0;
 | |
|     VALUE *vm_stack = fiber_initialize_coroutine(fiber, &vm_stack_size);
 | |
| 
 | |
|     /* initialize cont */
 | |
|     cont->saved_vm_stack.ptr = NULL;
 | |
|     rb_ec_initialize_vm_stack(sec, vm_stack, vm_stack_size / sizeof(VALUE));
 | |
| 
 | |
|     sec->tag = NULL;
 | |
|     sec->local_storage = NULL;
 | |
|     sec->local_storage_recursive_hash = Qnil;
 | |
|     sec->local_storage_recursive_hash_for_trace = Qnil;
 | |
| }
 | |
| 
 | |
| /* :nodoc: */
 | |
| static VALUE
 | |
| rb_fiber_initialize(int argc, VALUE* argv, VALUE self)
 | |
| {
 | |
|     return fiber_initialize(self, rb_block_proc(), &shared_fiber_pool);
 | |
| }
 | |
| 
 | |
| VALUE
 | |
| rb_fiber_new(VALUE (*func)(ANYARGS), VALUE obj)
 | |
| {
 | |
|     return fiber_initialize(fiber_alloc(rb_cFiber), rb_proc_new(func, obj), &shared_fiber_pool);
 | |
| }
 | |
| 
 | |
| static void rb_fiber_terminate(rb_fiber_t *fiber, int need_interrupt);
 | |
| 
 | |
| void
 | |
| rb_fiber_start(void)
 | |
| {
 | |
|     rb_thread_t * volatile th = GET_THREAD();
 | |
|     rb_fiber_t *fiber = th->ec->fiber_ptr;
 | |
|     rb_proc_t *proc;
 | |
|     enum ruby_tag_type state;
 | |
|     int need_interrupt = TRUE;
 | |
| 
 | |
|     VM_ASSERT(th->ec == ruby_current_execution_context_ptr);
 | |
|     VM_ASSERT(FIBER_RESUMED_P(fiber));
 | |
| 
 | |
|     EC_PUSH_TAG(th->ec);
 | |
|     if ((state = EC_EXEC_TAG()) == TAG_NONE) {
 | |
|         rb_context_t *cont = &VAR_FROM_MEMORY(fiber)->cont;
 | |
|         int argc;
 | |
|         const VALUE *argv, args = cont->value;
 | |
|         GetProcPtr(fiber->first_proc, proc);
 | |
|         argv = (argc = cont->argc) > 1 ? RARRAY_CONST_PTR(args) : &args;
 | |
|         cont->value = Qnil;
 | |
|         th->ec->errinfo = Qnil;
 | |
|         th->ec->root_lep = rb_vm_proc_local_ep(fiber->first_proc);
 | |
|         th->ec->root_svar = Qfalse;
 | |
| 
 | |
|         EXEC_EVENT_HOOK(th->ec, RUBY_EVENT_FIBER_SWITCH, th->self, 0, 0, 0, Qnil);
 | |
|         cont->value = rb_vm_invoke_proc(th->ec, proc, argc, argv, VM_BLOCK_HANDLER_NONE);
 | |
|     }
 | |
|     EC_POP_TAG();
 | |
| 
 | |
|     if (state) {
 | |
|         VALUE err = th->ec->errinfo;
 | |
|         VM_ASSERT(FIBER_RESUMED_P(fiber));
 | |
| 
 | |
|         if (state == TAG_RAISE || state == TAG_FATAL) {
 | |
|             rb_threadptr_pending_interrupt_enque(th, err);
 | |
|         }
 | |
|         else {
 | |
|             err = rb_vm_make_jump_tag_but_local_jump(state, err);
 | |
|             if (!NIL_P(err)) {
 | |
|                 rb_threadptr_pending_interrupt_enque(th, err);
 | |
|             }
 | |
|         }
 | |
|         need_interrupt = TRUE;
 | |
|     }
 | |
| 
 | |
|     rb_fiber_terminate(fiber, need_interrupt);
 | |
|     VM_UNREACHABLE(rb_fiber_start);
 | |
| }
 | |
| 
 | |
| static rb_fiber_t *
 | |
| root_fiber_alloc(rb_thread_t *th)
 | |
| {
 | |
|     VALUE fiber_value = fiber_alloc(rb_cFiber);
 | |
|     rb_fiber_t *fiber = th->ec->fiber_ptr;
 | |
| 
 | |
|     VM_ASSERT(DATA_PTR(fiber_value) == NULL);
 | |
|     VM_ASSERT(fiber->cont.type == FIBER_CONTEXT);
 | |
|     VM_ASSERT(fiber->status == FIBER_RESUMED);
 | |
| 
 | |
|     th->root_fiber = fiber;
 | |
|     DATA_PTR(fiber_value) = fiber;
 | |
|     fiber->cont.self = fiber_value;
 | |
| 
 | |
| #ifdef COROUTINE_PRIVATE_STACK
 | |
|     fiber->stack = fiber_pool_stack_acquire(&shared_fiber_pool);
 | |
|     coroutine_initialize_main(&fiber->context, fiber_pool_stack_base(&fiber->stack), fiber->stack.available, th->ec->machine.stack_start);
 | |
| #else
 | |
|     coroutine_initialize_main(&fiber->context);
 | |
| #endif
 | |
| 
 | |
|     return fiber;
 | |
| }
 | |
| 
 | |
| void
 | |
| rb_threadptr_root_fiber_setup(rb_thread_t *th)
 | |
| {
 | |
|     rb_fiber_t *fiber = ruby_mimmalloc(sizeof(rb_fiber_t));
 | |
|     MEMZERO(fiber, rb_fiber_t, 1);
 | |
|     fiber->cont.type = FIBER_CONTEXT;
 | |
|     fiber->cont.saved_ec.fiber_ptr = fiber;
 | |
|     fiber->cont.saved_ec.thread_ptr = th;
 | |
|     fiber_status_set(fiber, FIBER_RESUMED); /* skip CREATED */
 | |
|     th->ec = &fiber->cont.saved_ec;
 | |
| }
 | |
| 
 | |
| void
 | |
| rb_threadptr_root_fiber_release(rb_thread_t *th)
 | |
| {
 | |
|     if (th->root_fiber) {
 | |
|         /* ignore. A root fiber object will free th->ec */
 | |
|     }
 | |
|     else {
 | |
|         VM_ASSERT(th->ec->fiber_ptr->cont.type == FIBER_CONTEXT);
 | |
|         VM_ASSERT(th->ec->fiber_ptr->cont.self == 0);
 | |
|         fiber_free(th->ec->fiber_ptr);
 | |
| 
 | |
|         if (th->ec == ruby_current_execution_context_ptr) {
 | |
|             ruby_current_execution_context_ptr = NULL;
 | |
|         }
 | |
|         th->ec = NULL;
 | |
|     }
 | |
| }
 | |
| 
 | |
| void
 | |
| rb_threadptr_root_fiber_terminate(rb_thread_t *th)
 | |
| {
 | |
|     rb_fiber_t *fiber = th->ec->fiber_ptr;
 | |
| 
 | |
|     fiber->status = FIBER_TERMINATED;
 | |
| 
 | |
|     // The vm_stack is `alloca`ed on the thread stack, so it's gone too:
 | |
|     rb_ec_clear_vm_stack(th->ec);
 | |
| }
 | |
| 
 | |
| static inline rb_fiber_t*
 | |
| fiber_current(void)
 | |
| {
 | |
|     rb_execution_context_t *ec = GET_EC();
 | |
|     if (ec->fiber_ptr->cont.self == 0) {
 | |
|         root_fiber_alloc(rb_ec_thread_ptr(ec));
 | |
|     }
 | |
|     return ec->fiber_ptr;
 | |
| }
 | |
| 
 | |
| static inline rb_fiber_t*
 | |
| return_fiber(void)
 | |
| {
 | |
|     rb_fiber_t *fiber = fiber_current();
 | |
|     rb_fiber_t *prev = fiber->prev;
 | |
| 
 | |
|     if (!prev) {
 | |
|         rb_thread_t *th = GET_THREAD();
 | |
|         rb_fiber_t *root_fiber = th->root_fiber;
 | |
| 
 | |
|         VM_ASSERT(root_fiber != NULL);
 | |
| 
 | |
|         if (root_fiber == fiber) {
 | |
|             rb_raise(rb_eFiberError, "can't yield from root fiber");
 | |
|         }
 | |
|         return root_fiber;
 | |
|     }
 | |
|     else {
 | |
|         fiber->prev = NULL;
 | |
|         return prev;
 | |
|     }
 | |
| }
 | |
| 
 | |
| VALUE
 | |
| rb_fiber_current(void)
 | |
| {
 | |
|     return fiber_current()->cont.self;
 | |
| }
 | |
| 
 | |
| // Prepare to execute next_fiber on the given thread.
 | |
| static inline VALUE
 | |
| fiber_store(rb_fiber_t *next_fiber, rb_thread_t *th)
 | |
| {
 | |
|     rb_fiber_t *fiber;
 | |
| 
 | |
|     if (th->ec->fiber_ptr != NULL) {
 | |
|         fiber = th->ec->fiber_ptr;
 | |
|     }
 | |
|     else {
 | |
|         /* create root fiber */
 | |
|         fiber = root_fiber_alloc(th);
 | |
|     }
 | |
| 
 | |
|     if (FIBER_CREATED_P(next_fiber)) {
 | |
|         fiber_prepare_stack(next_fiber);
 | |
|     }
 | |
| 
 | |
|     VM_ASSERT(FIBER_RESUMED_P(fiber) || FIBER_TERMINATED_P(fiber));
 | |
|     VM_ASSERT(FIBER_RUNNABLE_P(next_fiber));
 | |
| 
 | |
|     if (FIBER_RESUMED_P(fiber)) fiber_status_set(fiber, FIBER_SUSPENDED);
 | |
| 
 | |
|     fiber_status_set(next_fiber, FIBER_RESUMED);
 | |
|     fiber_setcontext(next_fiber, fiber);
 | |
| 
 | |
|     fiber = th->ec->fiber_ptr;
 | |
| 
 | |
|     /* Raise an exception if that was the result of executing the fiber */
 | |
|     if (fiber->cont.argc == -1) rb_exc_raise(fiber->cont.value);
 | |
| 
 | |
|     return fiber->cont.value;
 | |
| }
 | |
| 
 | |
| static inline VALUE
 | |
| fiber_switch(rb_fiber_t *fiber, int argc, const VALUE *argv, int is_resume)
 | |
| {
 | |
|     VALUE value;
 | |
|     rb_context_t *cont = &fiber->cont;
 | |
|     rb_thread_t *th = GET_THREAD();
 | |
| 
 | |
|     /* make sure the root_fiber object is available */
 | |
|     if (th->root_fiber == NULL) root_fiber_alloc(th);
 | |
| 
 | |
|     if (th->ec->fiber_ptr == fiber) {
 | |
|         /* ignore fiber context switch
 | |
|          * because destination fiber is same as current fiber
 | |
|          */
 | |
|         return make_passing_arg(argc, argv);
 | |
|     }
 | |
| 
 | |
|     if (cont_thread_value(cont) != th->self) {
 | |
|         rb_raise(rb_eFiberError, "fiber called across threads");
 | |
|     }
 | |
|     else if (cont->saved_ec.protect_tag != th->ec->protect_tag) {
 | |
|         rb_raise(rb_eFiberError, "fiber called across stack rewinding barrier");
 | |
|     }
 | |
|     else if (FIBER_TERMINATED_P(fiber)) {
 | |
|         value = rb_exc_new2(rb_eFiberError, "dead fiber called");
 | |
| 
 | |
|         if (!FIBER_TERMINATED_P(th->ec->fiber_ptr)) {
 | |
|             rb_exc_raise(value);
 | |
|             VM_UNREACHABLE(fiber_switch);
 | |
|         }
 | |
|         else {
 | |
|             /* th->ec->fiber_ptr is also dead => switch to root fiber */
 | |
|             /* (this means we're being called from rb_fiber_terminate, */
 | |
|             /* and the terminated fiber's return_fiber() is already dead) */
 | |
|             VM_ASSERT(FIBER_SUSPENDED_P(th->root_fiber));
 | |
| 
 | |
|             cont = &th->root_fiber->cont;
 | |
|             cont->argc = -1;
 | |
|             cont->value = value;
 | |
| 
 | |
|             fiber_setcontext(th->root_fiber, th->ec->fiber_ptr);
 | |
| 
 | |
|             VM_UNREACHABLE(fiber_switch);
 | |
|         }
 | |
|     }
 | |
| 
 | |
|     if (is_resume) {
 | |
|         fiber->prev = fiber_current();
 | |
|     }
 | |
| 
 | |
|     VM_ASSERT(FIBER_RUNNABLE_P(fiber));
 | |
| 
 | |
|     cont->argc = argc;
 | |
|     cont->value = make_passing_arg(argc, argv);
 | |
| 
 | |
|     value = fiber_store(fiber, th);
 | |
| 
 | |
|     if (is_resume && FIBER_TERMINATED_P(fiber)) {
 | |
|         fiber_stack_release(fiber);
 | |
|     }
 | |
| 
 | |
|     RUBY_VM_CHECK_INTS(th->ec);
 | |
| 
 | |
|     EXEC_EVENT_HOOK(th->ec, RUBY_EVENT_FIBER_SWITCH, th->self, 0, 0, 0, Qnil);
 | |
| 
 | |
|     return value;
 | |
| }
 | |
| 
 | |
| VALUE
 | |
| rb_fiber_transfer(VALUE fiber_value, int argc, const VALUE *argv)
 | |
| {
 | |
|     return fiber_switch(fiber_ptr(fiber_value), argc, argv, 0);
 | |
| }
 | |
| 
 | |
| void
 | |
| rb_fiber_close(rb_fiber_t *fiber)
 | |
| {
 | |
|     fiber_status_set(fiber, FIBER_TERMINATED);
 | |
| }
 | |
| 
 | |
| static void
 | |
| rb_fiber_terminate(rb_fiber_t *fiber, int need_interrupt)
 | |
| {
 | |
|     VALUE value = fiber->cont.value;
 | |
|     rb_fiber_t *next_fiber;
 | |
| 
 | |
|     VM_ASSERT(FIBER_RESUMED_P(fiber));
 | |
|     rb_fiber_close(fiber);
 | |
| 
 | |
|     coroutine_destroy(&fiber->context);
 | |
| 
 | |
|     fiber->cont.machine.stack = NULL;
 | |
|     fiber->cont.machine.stack_size = 0;
 | |
| 
 | |
|     next_fiber = return_fiber();
 | |
|     if (need_interrupt) RUBY_VM_SET_INTERRUPT(&next_fiber->cont.saved_ec);
 | |
|     fiber_switch(next_fiber, 1, &value, 0);
 | |
| }
 | |
| 
 | |
| VALUE
 | |
| rb_fiber_resume(VALUE fiber_value, int argc, const VALUE *argv)
 | |
| {
 | |
|     rb_fiber_t *fiber = fiber_ptr(fiber_value);
 | |
| 
 | |
|     if (argc == -1 && FIBER_CREATED_P(fiber)) {
 | |
|         rb_raise(rb_eFiberError, "cannot raise exception on unborn fiber");
 | |
|     }
 | |
| 
 | |
|     if (fiber->prev != 0 || fiber_is_root_p(fiber)) {
 | |
|         rb_raise(rb_eFiberError, "double resume");
 | |
|     }
 | |
| 
 | |
|     if (fiber->transferred != 0) {
 | |
|         rb_raise(rb_eFiberError, "cannot resume transferred Fiber");
 | |
|     }
 | |
| 
 | |
|     return fiber_switch(fiber, argc, argv, 1);
 | |
| }
 | |
| 
 | |
| VALUE
 | |
| rb_fiber_yield(int argc, const VALUE *argv)
 | |
| {
 | |
|     return fiber_switch(return_fiber(), argc, argv, 0);
 | |
| }
 | |
| 
 | |
| void
 | |
| rb_fiber_reset_root_local_storage(rb_thread_t *th)
 | |
| {
 | |
|     if (th->root_fiber && th->root_fiber != th->ec->fiber_ptr) {
 | |
|         th->ec->local_storage = th->root_fiber->cont.saved_ec.local_storage;
 | |
|     }
 | |
| }
 | |
| 
 | |
| /*
 | |
|  *  call-seq:
 | |
|  *     fiber.alive? -> true or false
 | |
|  *
 | |
|  *  Returns true if the fiber can still be resumed (or transferred
 | |
|  *  to). After finishing execution of the fiber block this method will
 | |
|  *  always return false. You need to <code>require 'fiber'</code>
 | |
|  *  before using this method.
 | |
|  */
 | |
| VALUE
 | |
| rb_fiber_alive_p(VALUE fiber_value)
 | |
| {
 | |
|     return FIBER_TERMINATED_P(fiber_ptr(fiber_value)) ? Qfalse : Qtrue;
 | |
| }
 | |
| 
 | |
| /*
 | |
|  *  call-seq:
 | |
|  *     fiber.resume(args, ...) -> obj
 | |
|  *
 | |
|  *  Resumes the fiber from the point at which the last Fiber.yield was
 | |
|  *  called, or starts running it if it is the first call to
 | |
|  *  #resume. Arguments passed to resume will be the value of the
 | |
|  *  Fiber.yield expression or will be passed as block parameters to
 | |
|  *  the fiber's block if this is the first #resume.
 | |
|  *
 | |
|  *  Alternatively, when resume is called it evaluates to the arguments passed
 | |
|  *  to the next Fiber.yield statement inside the fiber's block
 | |
|  *  or to the block value if it runs to completion without any
 | |
|  *  Fiber.yield
 | |
|  */
 | |
| static VALUE
 | |
| rb_fiber_m_resume(int argc, VALUE *argv, VALUE fiber)
 | |
| {
 | |
|     return rb_fiber_resume(fiber, argc, argv);
 | |
| }
 | |
| 
 | |
| /*
 | |
|  *  call-seq:
 | |
|  *     fiber.raise                                 -> obj
 | |
|  *     fiber.raise(string)                         -> obj
 | |
|  *     fiber.raise(exception [, string [, array]]) -> obj
 | |
|  *
 | |
|  *  Raises an exception in the fiber at the point at which the last
 | |
|  *  Fiber.yield was called, or at the start if neither +resume+
 | |
|  *  nor +raise+ were called before.
 | |
|  *
 | |
|  *  With no arguments, raises a +RuntimeError+. With a single +String+
 | |
|  *  argument, raises a +RuntimeError+ with the string as a message.  Otherwise,
 | |
|  *  the first parameter should be the name of an +Exception+ class (or an
 | |
|  *  object that returns an +Exception+ object when sent an +exception+
 | |
|  *  message). The optional second parameter sets the message associated with
 | |
|  *  the exception, and the third parameter is an array of callback information.
 | |
|  *  Exceptions are caught by the +rescue+ clause of <code>begin...end</code>
 | |
|  *  blocks.
 | |
|  */
 | |
| static VALUE
 | |
| rb_fiber_raise(int argc, VALUE *argv, VALUE fiber)
 | |
| {
 | |
|     VALUE exc = rb_make_exception(argc, argv);
 | |
|     return rb_fiber_resume(fiber, -1, &exc);
 | |
| }
 | |
| 
 | |
| /*
 | |
|  *  call-seq:
 | |
|  *     fiber.transfer(args, ...) -> obj
 | |
|  *
 | |
|  *  Transfer control to another fiber, resuming it from where it last
 | |
|  *  stopped or starting it if it was not resumed before. The calling
 | |
|  *  fiber will be suspended much like in a call to
 | |
|  *  Fiber.yield. You need to <code>require 'fiber'</code>
 | |
|  *  before using this method.
 | |
|  *
 | |
|  *  The fiber which receives the transfer call is treats it much like
 | |
|  *  a resume call. Arguments passed to transfer are treated like those
 | |
|  *  passed to resume.
 | |
|  *
 | |
|  *  You cannot resume a fiber that transferred control to another one.
 | |
|  *  This will cause a double resume error. You need to transfer control
 | |
|  *  back to this fiber before it can yield and resume.
 | |
|  *
 | |
|  *  Example:
 | |
|  *
 | |
|  *    fiber1 = Fiber.new do
 | |
|  *      puts "In Fiber 1"
 | |
|  *      Fiber.yield
 | |
|  *    end
 | |
|  *
 | |
|  *    fiber2 = Fiber.new do
 | |
|  *      puts "In Fiber 2"
 | |
|  *      fiber1.transfer
 | |
|  *      puts "Never see this message"
 | |
|  *    end
 | |
|  *
 | |
|  *    fiber3 = Fiber.new do
 | |
|  *      puts "In Fiber 3"
 | |
|  *    end
 | |
|  *
 | |
|  *    fiber2.resume
 | |
|  *    fiber3.resume
 | |
|  *
 | |
|  *  <em>produces</em>
 | |
|  *
 | |
|  *    In fiber 2
 | |
|  *    In fiber 1
 | |
|  *    In fiber 3
 | |
|  *
 | |
|  */
 | |
| static VALUE
 | |
| rb_fiber_m_transfer(int argc, VALUE *argv, VALUE fiber_value)
 | |
| {
 | |
|     rb_fiber_t *fiber = fiber_ptr(fiber_value);
 | |
|     fiber->transferred = 1;
 | |
|     return fiber_switch(fiber, argc, argv, 0);
 | |
| }
 | |
| 
 | |
| /*
 | |
|  *  call-seq:
 | |
|  *     Fiber.yield(args, ...) -> obj
 | |
|  *
 | |
|  *  Yields control back to the context that resumed the fiber, passing
 | |
|  *  along any arguments that were passed to it. The fiber will resume
 | |
|  *  processing at this point when #resume is called next.
 | |
|  *  Any arguments passed to the next #resume will be the value that
 | |
|  *  this Fiber.yield expression evaluates to.
 | |
|  */
 | |
| static VALUE
 | |
| rb_fiber_s_yield(int argc, VALUE *argv, VALUE klass)
 | |
| {
 | |
|     return rb_fiber_yield(argc, argv);
 | |
| }
 | |
| 
 | |
| /*
 | |
|  *  call-seq:
 | |
|  *     Fiber.current() -> fiber
 | |
|  *
 | |
|  *  Returns the current fiber. You need to <code>require 'fiber'</code>
 | |
|  *  before using this method. If you are not running in the context of
 | |
|  *  a fiber this method will return the root fiber.
 | |
|  */
 | |
| static VALUE
 | |
| rb_fiber_s_current(VALUE klass)
 | |
| {
 | |
|     return rb_fiber_current();
 | |
| }
 | |
| 
 | |
| /*
 | |
|  * call-seq:
 | |
|  *   fiber.to_s   -> string
 | |
|  *
 | |
|  * Returns fiber information string.
 | |
|  *
 | |
|  */
 | |
| 
 | |
| static VALUE
 | |
| fiber_to_s(VALUE fiber_value)
 | |
| {
 | |
|     const rb_fiber_t *fiber = fiber_ptr(fiber_value);
 | |
|     const rb_proc_t *proc;
 | |
|     char status_info[0x10];
 | |
| 
 | |
|     snprintf(status_info, 0x10, " (%s)", fiber_status_name(fiber->status));
 | |
|     if (!rb_obj_is_proc(fiber->first_proc)) {
 | |
|         VALUE str = rb_any_to_s(fiber_value);
 | |
|         strlcat(status_info, ">", sizeof(status_info));
 | |
|         rb_str_set_len(str, RSTRING_LEN(str)-1);
 | |
|         rb_str_cat_cstr(str, status_info);
 | |
|         return str;
 | |
|     }
 | |
|     GetProcPtr(fiber->first_proc, proc);
 | |
|     return rb_block_to_s(fiber_value, &proc->block, status_info);
 | |
| }
 | |
| 
 | |
| #ifdef HAVE_WORKING_FORK
 | |
| void
 | |
| rb_fiber_atfork(rb_thread_t *th)
 | |
| {
 | |
|     if (th->root_fiber) {
 | |
|         if (&th->root_fiber->cont.saved_ec != th->ec) {
 | |
|             th->root_fiber = th->ec->fiber_ptr;
 | |
|         }
 | |
|         th->root_fiber->prev = 0;
 | |
|     }
 | |
| }
 | |
| #endif
 | |
| 
 | |
| #ifdef RB_EXPERIMENTAL_FIBER_POOL
 | |
| static void
 | |
| fiber_pool_free(void *ptr)
 | |
| {
 | |
|     struct fiber_pool * fiber_pool = ptr;
 | |
|     RUBY_FREE_ENTER("fiber_pool");
 | |
| 
 | |
|     fiber_pool_free_allocations(fiber_pool->allocations);
 | |
|     ruby_xfree(fiber_pool);
 | |
| 
 | |
|     RUBY_FREE_LEAVE("fiber_pool");
 | |
| }
 | |
| 
 | |
| static size_t
 | |
| fiber_pool_memsize(const void *ptr)
 | |
| {
 | |
|     const struct fiber_pool * fiber_pool = ptr;
 | |
|     size_t size = sizeof(*fiber_pool);
 | |
| 
 | |
|     size += fiber_pool->count * fiber_pool->size;
 | |
| 
 | |
|     return size;
 | |
| }
 | |
| 
 | |
| static const rb_data_type_t FiberPoolDataType = {
 | |
|     "fiber_pool",
 | |
|     {NULL, fiber_pool_free, fiber_pool_memsize,},
 | |
|     0, 0, RUBY_TYPED_FREE_IMMEDIATELY
 | |
| };
 | |
| 
 | |
| static VALUE
 | |
| fiber_pool_alloc(VALUE klass)
 | |
| {
 | |
|     struct fiber_pool * fiber_pool = RB_ALLOC(struct fiber_pool);
 | |
| 
 | |
|     return TypedData_Wrap_Struct(klass, &FiberPoolDataType, fiber_pool);
 | |
| }
 | |
| 
 | |
| static VALUE
 | |
| rb_fiber_pool_initialize(int argc, VALUE* argv, VALUE self)
 | |
| {
 | |
|     rb_thread_t *th = GET_THREAD();
 | |
|     VALUE size = Qnil, count = Qnil, vm_stack_size = Qnil;
 | |
|     struct fiber_pool * fiber_pool = NULL;
 | |
| 
 | |
|     // Maybe these should be keyworkd arguments.
 | |
|     rb_scan_args(argc, argv, "03", &size, &count, &vm_stack_size);
 | |
| 
 | |
|     if (NIL_P(size)) {
 | |
|         size = INT2NUM(th->vm->default_params.fiber_machine_stack_size);
 | |
|     }
 | |
| 
 | |
|     if (NIL_P(count)) {
 | |
|         count = INT2NUM(128);
 | |
|     }
 | |
| 
 | |
|     if (NIL_P(vm_stack_size)) {
 | |
|         vm_stack_size = INT2NUM(th->vm->default_params.fiber_vm_stack_size);
 | |
|     }
 | |
| 
 | |
|     TypedData_Get_Struct(self, struct fiber_pool, &FiberPoolDataType, fiber_pool);
 | |
| 
 | |
|     fiber_pool_initialize(fiber_pool, NUM2SIZET(size), NUM2SIZET(count), NUM2SIZET(vm_stack_size));
 | |
| 
 | |
|     return self;
 | |
| }
 | |
| #endif
 | |
| 
 | |
| /*
 | |
|  *  Document-class: FiberError
 | |
|  *
 | |
|  *  Raised when an invalid operation is attempted on a Fiber, in
 | |
|  *  particular when attempting to call/resume a dead fiber,
 | |
|  *  attempting to yield from the root fiber, or calling a fiber across
 | |
|  *  threads.
 | |
|  *
 | |
|  *     fiber = Fiber.new{}
 | |
|  *     fiber.resume #=> nil
 | |
|  *     fiber.resume #=> FiberError: dead fiber called
 | |
|  */
 | |
| 
 | |
| void
 | |
| Init_Cont(void)
 | |
| {
 | |
|     rb_thread_t *th = GET_THREAD();
 | |
|     size_t vm_stack_size = th->vm->default_params.fiber_vm_stack_size;
 | |
|     size_t machine_stack_size = th->vm->default_params.fiber_machine_stack_size;
 | |
|     size_t stack_size = machine_stack_size + vm_stack_size;
 | |
| 
 | |
| #ifdef _WIN32
 | |
|     SYSTEM_INFO info;
 | |
|     GetSystemInfo(&info);
 | |
|     pagesize = info.dwPageSize;
 | |
| #else /* not WIN32 */
 | |
|     pagesize = sysconf(_SC_PAGESIZE);
 | |
| #endif
 | |
|     SET_MACHINE_STACK_END(&th->ec->machine.stack_end);
 | |
| 
 | |
|     fiber_pool_initialize(&shared_fiber_pool, stack_size, FIBER_POOL_INITIAL_SIZE, vm_stack_size);
 | |
| 
 | |
|     char * fiber_shared_fiber_pool_free_stacks = getenv("RUBY_SHARED_FIBER_POOL_FREE_STACKS");
 | |
|     if (fiber_shared_fiber_pool_free_stacks) {
 | |
|         shared_fiber_pool.free_stacks = atoi(fiber_shared_fiber_pool_free_stacks);
 | |
|     }
 | |
| 
 | |
|     rb_cFiber = rb_define_class("Fiber", rb_cObject);
 | |
|     rb_define_alloc_func(rb_cFiber, fiber_alloc);
 | |
|     rb_eFiberError = rb_define_class("FiberError", rb_eStandardError);
 | |
|     rb_define_singleton_method(rb_cFiber, "yield", rb_fiber_s_yield, -1);
 | |
|     rb_define_method(rb_cFiber, "initialize", rb_fiber_initialize, -1);
 | |
|     rb_define_method(rb_cFiber, "resume", rb_fiber_m_resume, -1);
 | |
|     rb_define_method(rb_cFiber, "raise", rb_fiber_raise, -1);
 | |
|     rb_define_method(rb_cFiber, "to_s", fiber_to_s, 0);
 | |
|     rb_define_alias(rb_cFiber, "inspect", "to_s");
 | |
| 
 | |
| #ifdef RB_EXPERIMENTAL_FIBER_POOL
 | |
|     rb_cFiberPool = rb_define_class("Pool", rb_cFiber);
 | |
|     rb_define_alloc_func(rb_cFiberPool, fiber_pool_alloc);
 | |
|     rb_define_method(rb_cFiberPool, "initialize", rb_fiber_pool_initialize, -1);
 | |
| #endif
 | |
| }
 | |
| 
 | |
| RUBY_SYMBOL_EXPORT_BEGIN
 | |
| 
 | |
| void
 | |
| ruby_Init_Continuation_body(void)
 | |
| {
 | |
|     rb_cContinuation = rb_define_class("Continuation", rb_cObject);
 | |
|     rb_undef_alloc_func(rb_cContinuation);
 | |
|     rb_undef_method(CLASS_OF(rb_cContinuation), "new");
 | |
|     rb_define_method(rb_cContinuation, "call", rb_cont_call, -1);
 | |
|     rb_define_method(rb_cContinuation, "[]", rb_cont_call, -1);
 | |
|     rb_define_global_function("callcc", rb_callcc, 0);
 | |
| }
 | |
| 
 | |
| void
 | |
| ruby_Init_Fiber_as_Coroutine(void)
 | |
| {
 | |
|     rb_define_method(rb_cFiber, "transfer", rb_fiber_m_transfer, -1);
 | |
|     rb_define_method(rb_cFiber, "alive?", rb_fiber_alive_p, 0);
 | |
|     rb_define_singleton_method(rb_cFiber, "current", rb_fiber_s_current, 0);
 | |
| }
 | |
| 
 | |
| RUBY_SYMBOL_EXPORT_END
 | 
