source: libcfa/src/concurrency/coroutine.cfa @ ff2a33e

ADTarm-ehast-experimentalenumforall-pointer-decayjacob/cs343-translationjenkins-sandboxnew-astnew-ast-unique-exprpthread-emulationqualifiedEnum
Last change on this file since ff2a33e was 3623f9d, checked in by Thierry Delisle <tdelisle@…>, 5 years ago

Fixed warning in libcfa

  • Property mode set to 100644
File size: 7.0 KB
Line 
1//
2// Cforall Version 1.0.0 Copyright (C) 2016 University of Waterloo
3//
4// The contents of this file are covered under the licence agreement in the
5// file "LICENCE" distributed with Cforall.
6//
7// coroutine.c --
8//
9// Author           : Thierry Delisle
10// Created On       : Mon Nov 28 12:27:26 2016
11// Last Modified By : Peter A. Buhr
12// Last Modified On : Fri Mar 30 17:20:57 2018
13// Update Count     : 9
14//
15
16#include "coroutine.hfa"
17
18extern "C" {
19#include <stddef.h>
20#include <malloc.h>
21#include <errno.h>
22#include <string.h>
23#include <unistd.h>
24// use this define to make unwind.h play nice, definetely a hack
25#define HIDE_EXPORTS
26#include <unwind.h>
27#undef HIDE_EXPORTS
28#include <sys/mman.h>
29}
30
31#include "kernel_private.hfa"
32
33#define __CFA_INVOKE_PRIVATE__
34#include "invoke.h"
35
36extern "C" {
37        void _CtxCoroutine_Unwind(struct _Unwind_Exception * storage, struct coroutine_desc *) __attribute__ ((__noreturn__));
38        static void _CtxCoroutine_UnwindCleanup(_Unwind_Reason_Code, struct _Unwind_Exception *) __attribute__ ((__noreturn__));
39        static void _CtxCoroutine_UnwindCleanup(_Unwind_Reason_Code, struct _Unwind_Exception *) {
40                abort();
41        }
42
43        extern void CtxRet( struct __stack_context_t * to ) asm ("CtxRet") __attribute__ ((__noreturn__));
44}
45
46//-----------------------------------------------------------------------------
47// Global state variables
48
49// minimum feasible stack size in bytes
50#define MinStackSize 1000
51extern size_t __page_size;                              // architecture pagesize HACK, should go in proper runtime singleton
52
53void __stack_prepare( __stack_info_t * this, size_t create_size );
54
55//-----------------------------------------------------------------------------
56// Coroutine ctors and dtors
57void ?{}( __stack_info_t & this, void * storage, size_t storageSize ) {
58        this.storage   = (__stack_t *)storage;
59
60        // Did we get a piece of storage ?
61        if (this.storage || storageSize != 0) {
62                // We either got a piece of storage or the user asked for a specific size
63                // Immediately create the stack
64                // (This is slightly unintuitive that non-default sized coroutines create are eagerly created
65                // but it avoids that all coroutines carry an unnecessary size)
66                verify( storageSize != 0 );
67                __stack_prepare( &this, storageSize );
68        }
69}
70
71void ^?{}(__stack_info_t & this) {
72        bool userStack = ((intptr_t)this.storage & 0x1) != 0;
73        if ( ! userStack && this.storage ) {
74                __attribute__((may_alias)) intptr_t * istorage = (intptr_t *)&this.storage;
75                *istorage &= (intptr_t)-1;
76
77                void * storage = this.storage->limit;
78                __cfaabi_dbg_debug_do(
79                        storage = (char*)(storage) - __page_size;
80                        if ( mprotect( storage, __page_size, PROT_READ | PROT_WRITE ) == -1 ) {
81                                abort( "(coStack_t *)%p.^?{}() : internal error, mprotect failure, error(%d) %s.", &this, errno, strerror( errno ) );
82                        }
83                );
84                __cfaabi_dbg_print_safe("Kernel : Deleting stack %p\n", storage);
85                free( storage );
86        }
87}
88
89void ?{}( coroutine_desc & this, const char * name, void * storage, size_t storageSize ) with( this ) {
90        (this.context){NULL, NULL};
91        (this.stack){storage, storageSize};
92        this.name = name;
93        state = Start;
94        starter = NULL;
95        last = NULL;
96        cancellation = NULL;
97}
98
99void ^?{}(coroutine_desc& this) {
100        if(this.state != Halted && this.state != Start && this.state != Primed) {
101                coroutine_desc * src = TL_GET( this_thread )->curr_cor;
102                coroutine_desc * dst = &this;
103
104                struct _Unwind_Exception storage;
105                storage.exception_class = -1;
106                storage.exception_cleanup = _CtxCoroutine_UnwindCleanup;
107                this.cancellation = &storage;
108                this.last = src;
109
110                // not resuming self ?
111                if ( src == dst ) {
112                        abort( "Attempt by coroutine %.256s (%p) to terminate itself.\n", src->name, src );
113                }
114
115                CoroutineCtxSwitch( src, dst );
116        }
117}
118
119// Part of the Public API
120// Not inline since only ever called once per coroutine
121forall(dtype T | is_coroutine(T))
122void prime(T& cor) {
123        coroutine_desc* this = get_coroutine(cor);
124        assert(this->state == Start);
125
126        this->state = Primed;
127        resume(cor);
128}
129
130[void *, size_t] __stack_alloc( size_t storageSize ) {
131        static const size_t stack_data_size = libCeiling( sizeof(__stack_t), 16 ); // minimum alignment
132        assert(__page_size != 0l);
133        size_t size = libCeiling( storageSize, 16 ) + stack_data_size;
134
135        // If we are running debug, we also need to allocate a guardpage to catch stack overflows.
136        void * storage;
137        __cfaabi_dbg_debug_do(
138                storage = memalign( __page_size, size + __page_size );
139        );
140        __cfaabi_dbg_no_debug_do(
141                storage = (void*)malloc(size);
142        );
143
144        __cfaabi_dbg_print_safe("Kernel : Created stack %p of size %zu\n", storage, size);
145        __cfaabi_dbg_debug_do(
146                if ( mprotect( storage, __page_size, PROT_NONE ) == -1 ) {
147                        abort( "__stack_alloc : internal error, mprotect failure, error(%d) %s.", (int)errno, strerror( (int)errno ) );
148                }
149                storage = (void *)(((intptr_t)storage) + __page_size);
150        );
151
152        verify( ((intptr_t)storage & (libAlign() - 1)) == 0ul );
153        return [storage, size];
154}
155
156void __stack_prepare( __stack_info_t * this, size_t create_size ) {
157        static const size_t stack_data_size = libCeiling( sizeof(__stack_t), 16 ); // minimum alignment
158        bool userStack;
159        void * storage;
160        size_t size;
161        if ( !this->storage ) {
162                userStack = false;
163                [storage, size] = __stack_alloc( create_size );
164        } else {
165                userStack = true;
166                __cfaabi_dbg_print_safe("Kernel : stack obj %p using user stack %p(%zd bytes)\n", this, this->storage, (intptr_t)this->storage->limit - (intptr_t)this->storage->base);
167
168                // The stack must be aligned, advance the pointer to the next align data
169                storage = (void*)libCeiling( (intptr_t)this->storage, libAlign());
170
171                // The size needs to be shrinked to fit all the extra data structure and be aligned
172                ptrdiff_t diff = (intptr_t)storage - (intptr_t)this->storage;
173                size = libFloor(create_size - stack_data_size - diff, libAlign());
174        } // if
175        assertf( size >= MinStackSize, "Stack size %zd provides less than minimum of %d bytes for a stack.", size, MinStackSize );
176
177        this->storage = (__stack_t *)((intptr_t)storage + size);
178        this->storage->limit = storage;
179        this->storage->base  = (void*)((intptr_t)storage + size);
180        __attribute__((may_alias)) intptr_t * istorage = (intptr_t*)&this->storage;
181        *istorage |= userStack ? 0x1 : 0x0;
182}
183
184// We need to call suspend from invoke.c, so we expose this wrapper that
185// is not inline (We can't inline Cforall in C)
186extern "C" {
187        void __suspend_internal(void) {
188                suspend();
189        }
190
191        void __leave_coroutine( coroutine_desc * src ) {
192                coroutine_desc * starter = src->cancellation != 0 ? src->last : src->starter;
193
194                src->state = Halted;
195
196                assertf( starter != 0,
197                        "Attempt to suspend/leave coroutine \"%.256s\" (%p) that has never been resumed.\n"
198                        "Possible cause is a suspend executed in a member called by a coroutine user rather than by the coroutine main.",
199                        src->name, src );
200                assertf( starter->state != Halted,
201                        "Attempt by coroutine \"%.256s\" (%p) to suspend/leave back to terminated coroutine \"%.256s\" (%p).\n"
202                        "Possible cause is terminated coroutine's main routine has already returned.",
203                        src->name, src, starter->name, starter );
204
205                CoroutineCtxSwitch( src, starter );
206        }
207}
208
209// Local Variables: //
210// mode: c //
211// tab-width: 4 //
212// End: //
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