|
| 1 | +// This file is a part of Julia. License is MIT: https://julialang.org/license |
| 2 | + |
| 3 | +#include "gc.h" |
| 4 | +#ifndef _OS_WINDOWS_ |
| 5 | +# include <sys/resource.h> |
| 6 | +#endif |
| 7 | + |
| 8 | +const size_t jl_guard_size = (4096 * 16); |
| 9 | + |
| 10 | +#ifdef _OS_WINDOWS_ |
| 11 | +#define MAP_FAILED NULL |
| 12 | +static void *malloc_stack(size_t bufsz) |
| 13 | +{ |
| 14 | + void *stk = VirtualAlloc(NULL, bufsz, MEM_RESERVE | MEM_COMMIT, PAGE_READWRITE); |
| 15 | + if (stk == NULL) |
| 16 | + return MAP_FAILED; |
| 17 | + DWORD dwOldProtect; |
| 18 | + if (!VirtualProtect(stk, jl_guard_size, PAGE_READWRITE | PAGE_GUARD, &dwOldProtect)) { |
| 19 | + VirtualFree(stk, 0, MEM_RELEASE); |
| 20 | + return MAP_FAILED; |
| 21 | + } |
| 22 | + return stk; |
| 23 | +} |
| 24 | + |
| 25 | + |
| 26 | +static void free_stack(void *stkbuf, size_t bufsz) |
| 27 | +{ |
| 28 | + VirtualFree(stkbuf, 0, MEM_RELEASE); |
| 29 | +} |
| 30 | + |
| 31 | +#else |
| 32 | + |
| 33 | +static void *malloc_stack(size_t bufsz) |
| 34 | +{ |
| 35 | + void* stk = mmap(0, bufsz, PROT_READ | PROT_WRITE, MAP_PRIVATE | MAP_ANONYMOUS, -1, 0); |
| 36 | + if (stk == MAP_FAILED) |
| 37 | + return MAP_FAILED; |
| 38 | +#if !defined(JL_HAVE_UCONTEXT) && !defined(JL_HAVE_SIGALTSTACK) |
| 39 | + // setup a guard page to detect stack overflow |
| 40 | + if (mprotect(stk, jl_guard_size, PROT_NONE) == -1) { |
| 41 | + munmap(stk, bufsz); |
| 42 | + return MAP_FAILED; |
| 43 | + } |
| 44 | +#endif |
| 45 | + return stk; |
| 46 | +} |
| 47 | + |
| 48 | +static void free_stack(void *stkbuf, size_t bufsz) |
| 49 | +{ |
| 50 | + munmap(stkbuf, bufsz); |
| 51 | +} |
| 52 | +#endif |
| 53 | + |
| 54 | + |
| 55 | +const unsigned pool_sizes[] = { |
| 56 | + 128 * 1024, |
| 57 | + 192 * 1024, |
| 58 | + 256 * 1024, |
| 59 | + 384 * 1024, |
| 60 | + 512 * 1024, |
| 61 | + 768 * 1024, |
| 62 | + 1024 * 1024, |
| 63 | + 1537 * 1024, |
| 64 | + 2048 * 1024, |
| 65 | + 3 * 1024 * 1024, |
| 66 | + 4 * 1024 * 1024, |
| 67 | + 6 * 1024 * 1024, |
| 68 | + 8 * 1024 * 1024, |
| 69 | + 12 * 1024 * 1024, |
| 70 | + 16 * 1024 * 1024, |
| 71 | + 24 * 1024 * 1024, |
| 72 | +}; |
| 73 | + |
| 74 | +static_assert(sizeof(pool_sizes) == JL_N_STACK_POOLS * sizeof(pool_sizes[0]), "JL_N_STACK_POOLS size mismatch"); |
| 75 | + |
| 76 | +static unsigned select_pool(size_t nb) |
| 77 | +{ |
| 78 | + unsigned pool_id = 0; |
| 79 | + while (pool_sizes[pool_id] < nb) |
| 80 | + pool_id++; |
| 81 | + return pool_id; |
| 82 | +} |
| 83 | + |
| 84 | + |
| 85 | +static void _jl_free_stack(jl_ptls_t ptls, void *stkbuf, size_t bufsz) |
| 86 | +{ |
| 87 | + if (bufsz <= pool_sizes[JL_N_STACK_POOLS - 1]) { |
| 88 | + unsigned pool_id = select_pool(bufsz); |
| 89 | + if (pool_sizes[pool_id] == bufsz) { |
| 90 | + arraylist_push(&ptls->heap.free_stacks[pool_id], stkbuf); |
| 91 | + return; |
| 92 | + } |
| 93 | + } |
| 94 | + free_stack(stkbuf, bufsz); |
| 95 | +} |
| 96 | + |
| 97 | + |
| 98 | +JL_DLLEXPORT void jl_free_stack(void *stkbuf, size_t bufsz) |
| 99 | +{ |
| 100 | + _jl_free_stack(jl_get_ptls_states(), stkbuf, bufsz); |
| 101 | +} |
| 102 | + |
| 103 | + |
| 104 | +JL_DLLEXPORT void *jl_malloc_stack(size_t *bufsz, jl_task_t *owner) |
| 105 | +{ |
| 106 | + jl_ptls_t ptls = jl_get_ptls_states(); |
| 107 | + size_t ssize = *bufsz; |
| 108 | + void *stk = NULL; |
| 109 | + if (ssize <= pool_sizes[JL_N_STACK_POOLS - 1]) { |
| 110 | + unsigned pool_id = select_pool(ssize); |
| 111 | + ssize = pool_sizes[pool_id]; |
| 112 | + arraylist_t *pool = &ptls->heap.free_stacks[pool_id]; |
| 113 | + if (pool->len > 0) { |
| 114 | + stk = arraylist_pop(pool); |
| 115 | + } |
| 116 | + } |
| 117 | + else { |
| 118 | + ssize = LLT_ALIGN(ssize, jl_page_size); |
| 119 | + } |
| 120 | + if (stk == NULL) { |
| 121 | + // TODO: allocate blocks of stacks? but need to mprotect individually anyways |
| 122 | + stk = malloc_stack(ssize); |
| 123 | + if (stk == MAP_FAILED) |
| 124 | + jl_throw(jl_memory_exception); |
| 125 | + } |
| 126 | + *bufsz = ssize; |
| 127 | + if (owner) { |
| 128 | + arraylist_t *live_tasks = &ptls->heap.live_tasks; |
| 129 | + arraylist_push(live_tasks, owner); |
| 130 | + } |
| 131 | + return stk; |
| 132 | +} |
| 133 | + |
| 134 | +void sweep_stack_pools(void) |
| 135 | +{ |
| 136 | +// TODO: deallocate stacks if we have too many sitting around unused |
| 137 | +// for (stk in halfof(free_stacks)) |
| 138 | +// free_stack(stk, pool_sz); |
| 139 | +// // then sweep the task stacks |
| 140 | +// for (t in live_tasks) |
| 141 | +// if (!gc-marked(t)) |
| 142 | +// stkbuf = t->stkbuf |
| 143 | +// bufsz = t->bufsz |
| 144 | +// if (stkbuf) |
| 145 | +// push(free_stacks[sz], stkbuf) |
| 146 | + for (int i = 0; i < jl_n_threads; i++) { |
| 147 | + jl_ptls_t ptls2 = jl_all_tls_states[i]; |
| 148 | + arraylist_t *live_tasks = &ptls2->heap.live_tasks; |
| 149 | + size_t n = 0; |
| 150 | + size_t ndel = 0; |
| 151 | + size_t l = live_tasks->len; |
| 152 | + void **lst = live_tasks->items; |
| 153 | + if (l == 0) |
| 154 | + continue; |
| 155 | + while (1) { |
| 156 | + jl_task_t *t = (jl_task_t*)lst[n]; |
| 157 | + if (gc_marked(jl_astaggedvalue(t)->bits.gc)) { |
| 158 | + n++; |
| 159 | + } |
| 160 | + else { |
| 161 | + ndel++; |
| 162 | + void *stkbuf = t->stkbuf; |
| 163 | + size_t bufsz = t->bufsz; |
| 164 | + if (stkbuf) { |
| 165 | + t->stkbuf = NULL; |
| 166 | + _jl_free_stack(ptls2, stkbuf, bufsz); |
| 167 | + } |
| 168 | + } |
| 169 | + if (n >= l - ndel) |
| 170 | + break; |
| 171 | + void *tmp = lst[n]; |
| 172 | + lst[n] = lst[n + ndel]; |
| 173 | + lst[n + ndel] = tmp; |
| 174 | + } |
| 175 | + live_tasks->len -= ndel; |
| 176 | + } |
| 177 | +} |
0 commit comments