summaryrefslogtreecommitdiffhomepage
path: root/src/nxt_fiber.c
diff options
context:
space:
mode:
Diffstat (limited to '')
-rw-r--r--src/nxt_fiber.c446
1 files changed, 446 insertions, 0 deletions
diff --git a/src/nxt_fiber.c b/src/nxt_fiber.c
new file mode 100644
index 00000000..74473f85
--- /dev/null
+++ b/src/nxt_fiber.c
@@ -0,0 +1,446 @@
+
+/*
+ * Copyright (C) Igor Sysoev
+ * Copyright (C) NGINX, Inc.
+ */
+
+#include <nxt_main.h>
+
+
+static char *nxt_fiber_create_stack(nxt_fiber_t *fib);
+static void nxt_fiber_switch_stack(nxt_fiber_t *fib, jmp_buf *parent);
+static void nxt_fiber_switch_handler(nxt_thread_t *thr, void *obj,
+ void *data);
+static void nxt_fiber_switch(nxt_thread_t *thr, nxt_fiber_t *fib);
+static void nxt_fiber_timer_handler(nxt_thread_t *thr, void *obj,
+ void *data);
+
+
+#define \
+nxt_fiber_enqueue(thr, fib) \
+ nxt_thread_work_queue_add(thr, &(thr)->work_queue.main, \
+ nxt_fiber_switch_handler, fib, NULL, thr->log)
+
+
+nxt_fiber_main_t *
+nxt_fiber_main_create(nxt_event_engine_t *engine)
+{
+ nxt_fiber_main_t *fm;
+
+ fm = nxt_zalloc(sizeof(nxt_fiber_main_t));
+ if (nxt_slow_path(fm == NULL)) {
+ return NULL;
+ }
+
+ fm->stack_size = 512 * 1024 - nxt_pagesize;
+ fm->idle = NULL;
+
+ return fm;
+}
+
+
+nxt_int_t
+nxt_fiber_create(nxt_fiber_start_t start, void *data, size_t stack)
+{
+ int ret;
+ jmp_buf parent;
+ nxt_fid_t fid;
+ nxt_fiber_t *fib;
+ nxt_thread_t *thr;
+ nxt_fiber_main_t *fm;
+
+ thr = nxt_thread();
+ fm = thr->engine->fibers;
+
+ fid = ++fm->fid;
+
+ if (fid == 0) {
+ fid = ++fm->fid;
+ }
+
+ fib = fm->idle;
+
+ if (fib != NULL) {
+ fm->idle = fib->next;
+ fib->fid = fid;
+ fib->start = start;
+ fib->data = data;
+ fib->main = fm;
+
+ nxt_log_debug(thr->log, "fiber create cached: %PF", fib->fid);
+ nxt_fiber_enqueue(thr, fib);
+ return NXT_OK;
+ }
+
+ nxt_log_debug(thr->log, "fiber create");
+
+ fib = nxt_malloc(sizeof(nxt_fiber_t));
+ if (nxt_slow_path(fib == NULL)) {
+ return NXT_ERROR;
+ }
+
+ fib->fid = fid;
+ fib->start = start;
+ fib->data = data;
+ fib->stack_size = fm->stack_size;
+ fib->main = fm;
+
+ fib->stack = nxt_fiber_create_stack(fib);
+
+ if (nxt_fast_path(fib->stack != NULL)) {
+
+ if (_setjmp(parent) != 0) {
+ nxt_log_debug(thr->log, "fiber create: %PF", fib->fid);
+ return NXT_OK;
+ }
+
+ nxt_fiber_switch_stack(fib, &parent);
+ /* It does not return if the switch was successful. */
+ }
+
+ ret = munmap(fib->stack - nxt_pagesize, fib->stack_size + nxt_pagesize);
+
+ if (nxt_slow_path(ret != 0)) {
+ nxt_log_alert(thr->log, "munmap() failed %E", nxt_errno);
+ }
+
+ nxt_free(fib);
+
+ return NXT_ERROR;
+}
+
+
+#if (NXT_LINUX)
+
+static char *
+nxt_fiber_create_stack(nxt_fiber_t *fib)
+{
+ char *s;
+ size_t size;
+
+ size = fib->stack_size + nxt_pagesize;
+
+ s = mmap(NULL, size, PROT_READ | PROT_WRITE,
+ MAP_PRIVATE | MAP_ANON | MAP_GROWSDOWN, -1, 0);
+
+ if (nxt_slow_path(s == MAP_FAILED)) {
+ nxt_thread_log_alert("fiber stack "
+ "mmap(%uz, MAP_PRIVATE|MAP_ANON|MAP_GROWSDOWN) failed %E",
+ size, nxt_errno);
+ return NULL;
+ }
+
+ if (nxt_slow_path(mprotect(s, nxt_pagesize, PROT_NONE) != 0)) {
+ nxt_thread_log_alert("fiber stack mprotect(%uz, PROT_NONE) failed %E",
+ size, nxt_errno);
+ return NULL;
+ }
+
+ s += nxt_pagesize;
+
+ nxt_thread_log_debug("fiber stack mmap: %p", s);
+
+ return s;
+}
+
+#else /* Generic version. */
+
+static char *
+nxt_fiber_create_stack(nxt_fiber_t *fib)
+{
+ char *s;
+ size_t size;
+
+ size = fib->stack_size + nxt_pagesize;
+
+ s = mmap(NULL, size, PROT_READ | PROT_WRITE, MAP_PRIVATE | MAP_ANON, -1, 0);
+
+ if (nxt_slow_path(s == MAP_FAILED)) {
+ nxt_thread_log_alert("fiber stack "
+ "mmap(%uz, MAP_PRIVATE|MAP_ANON) failed %E",
+ size, nxt_errno);
+ return NULL;
+ }
+
+ if (nxt_slow_path(mprotect(s, nxt_pagesize, PROT_NONE) != 0)) {
+ nxt_thread_log_alert("fiber stack mprotect(%uz, PROT_NONE) failed %E",
+ size, nxt_errno);
+ return NULL;
+ }
+
+ s += nxt_pagesize;
+
+ nxt_thread_log_debug("fiber stack mmap: %p", s);
+
+ return s;
+}
+
+#endif
+
+
+#if (NXT_LINUX && NXT_64BIT)
+
+/*
+ * Linux 64-bit ucontext version. 64-bit glibc makecontext() passes
+ * pointers as signed int's. The bug has been fixed in glibc 2.8.
+ */
+
+static void nxt_fiber_trampoline(uint32_t fh, uint32_t fl, uint32_t ph,
+ uint32_t pl);
+
+
+static void
+nxt_fiber_switch_stack(nxt_fiber_t *fib, jmp_buf *parent)
+{
+ ucontext_t uc;
+
+ nxt_thread_log_debug("fiber switch to stack: %p", fib->stack);
+
+ if (nxt_slow_path(getcontext(&uc) != 0)) {
+ nxt_thread_log_alert("getcontext() failed");
+ return;
+ }
+
+ uc.uc_link = NULL;
+ uc.uc_stack.ss_sp = fib->stack;
+ uc.uc_stack.ss_size = fib->stack_size;
+
+ makecontext(&uc, (void (*)(void)) nxt_fiber_trampoline, 4,
+ (uint32_t) ((uintptr_t) fib >> 32),
+ (uint32_t) ((uintptr_t) fib & 0xffffffff),
+ (uint32_t) ((uintptr_t) parent >> 32),
+ (uint32_t) ((uintptr_t) parent & 0xffffffff));
+
+ setcontext(&uc);
+
+ nxt_thread_log_alert("setcontext() failed");
+}
+
+
+static void
+nxt_fiber_trampoline(uint32_t fh, uint32_t fl, uint32_t ph, uint32_t pl)
+{
+ jmp_buf *parent;
+ nxt_fiber_t *fib;
+ nxt_thread_t *thr;
+
+ fib = (nxt_fiber_t *) (((uintptr_t) fh << 32) + fl);
+ parent = (jmp_buf *) (((uintptr_t) ph << 32) + pl);
+
+ thr = nxt_thread();
+
+ if (_setjmp(fib->jmp) == 0) {
+ nxt_log_debug(thr->log, "fiber return to parent stack");
+
+ nxt_fiber_enqueue(thr, fib);
+ _longjmp(*parent, 1);
+ nxt_unreachable();
+ }
+
+ nxt_log_debug(thr->log, "fiber start");
+
+ fib->start(fib->data);
+
+ nxt_fiber_exit(&fib->main->fiber, NULL);
+ nxt_unreachable();
+}
+
+#elif (NXT_HAVE_UCONTEXT)
+
+/* Generic ucontext version. */
+
+static void nxt_fiber_trampoline(nxt_fiber_t *fib, jmp_buf *parent);
+
+
+static void
+nxt_fiber_switch_stack(nxt_fiber_t *fib, jmp_buf *parent)
+{
+ ucontext_t uc;
+
+ nxt_thread_log_debug("fiber switch to stack: %p", fib->stack);
+
+ if (nxt_slow_path(getcontext(&uc) != 0)) {
+ nxt_thread_log_alert("getcontext() failed");
+ return;
+ }
+
+ uc.uc_link = NULL;
+ uc.uc_stack.ss_sp = fib->stack;
+ uc.uc_stack.ss_size = fib->stack_size;
+
+ makecontext(&uc, (void (*)(void)) nxt_fiber_trampoline, 2, fib, parent);
+
+ setcontext(&uc);
+
+#if !(NXT_SOLARIS)
+ /* Solaris declares setcontext() as __NORETURN. */
+
+ nxt_thread_log_alert("setcontext() failed");
+#endif
+}
+
+
+static void
+nxt_fiber_trampoline(nxt_fiber_t *fib, jmp_buf *parent)
+{
+ nxt_thread_t *thr;
+
+ thr = nxt_thread();
+
+ if (_setjmp(fib->jmp) == 0) {
+ nxt_log_debug(thr->log, "fiber return to parent stack");
+
+ nxt_fiber_enqueue(thr, fib);
+ _longjmp(*parent, 1);
+ nxt_unreachable();
+ }
+
+ nxt_log_debug(thr->log, "fiber start");
+
+ fib->start(fib->data);
+
+ nxt_fiber_exit(&fib->main->fiber, NULL);
+ nxt_unreachable();
+}
+
+#else
+
+#error No ucontext(3) interface.
+
+#endif
+
+
+static void
+nxt_fiber_switch_handler(nxt_thread_t *thr, void *obj, void *data)
+{
+ nxt_fiber_t *fib;
+
+ fib = obj;
+
+ nxt_fiber_switch(thr, fib);
+ nxt_unreachable();
+}
+
+
+static void
+nxt_fiber_switch(nxt_thread_t *thr, nxt_fiber_t *fib)
+{
+ nxt_log_debug(thr->log, "fiber switch: %PF", fib->fid);
+
+ thr->fiber = fib;
+ _longjmp(fib->jmp, 1);
+ nxt_unreachable();
+}
+
+
+nxt_fiber_t *
+nxt_fiber_self(nxt_thread_t *thr)
+{
+ return (nxt_fast_path(thr != NULL)) ? thr->fiber : NULL;
+}
+
+
+void
+nxt_fiber_yield(void)
+{
+ nxt_fiber_t *fib;
+ nxt_thread_t *thr;
+
+ thr = nxt_thread();
+ fib = thr->fiber;
+
+ if (_setjmp(fib->jmp) == 0) {
+
+ nxt_log_debug(thr->log, "fiber yield");
+
+ nxt_fiber_enqueue(thr, fib);
+ nxt_fiber_switch(thr, &fib->main->fiber);
+ nxt_unreachable();
+ }
+
+ nxt_log_debug(thr->log, "fiber yield return");
+}
+
+
+void
+nxt_fiber_sleep(nxt_msec_t timeout)
+{
+ nxt_fiber_t *fib;
+ nxt_thread_t *thr;
+
+ thr = nxt_thread();
+ fib = thr->fiber;
+
+ fib->timer.work_queue = &thr->work_queue.main;
+ fib->timer.handler = nxt_fiber_timer_handler;
+ fib->timer.log = &nxt_main_log;
+
+ nxt_event_timer_add(thr->engine, &fib->timer, timeout);
+
+ if (_setjmp(fib->jmp) == 0) {
+
+ nxt_log_debug(thr->log, "fiber sleep: %T", timeout);
+
+ nxt_fiber_switch(thr, &fib->main->fiber);
+ nxt_unreachable();
+ }
+
+ nxt_log_debug(thr->log, "fiber sleep return");
+}
+
+
+static void
+nxt_fiber_timer_handler(nxt_thread_t *thr, void *obj, void *data)
+{
+ nxt_fiber_t *fib;
+ nxt_event_timer_t *ev;
+
+ ev = obj;
+
+ nxt_log_debug(thr->log, "fiber timer handler");
+
+ fib = nxt_event_timer_data(ev, nxt_fiber_t, timer);
+
+ nxt_fiber_switch(thr, fib);
+ nxt_unreachable();
+}
+
+
+void
+nxt_fiber_wait(void)
+{
+ nxt_fiber_t *fib;
+ nxt_thread_t *thr;
+
+ thr = nxt_thread();
+ fib = thr->fiber;
+
+ if (_setjmp(fib->jmp) == 0) {
+ nxt_log_debug(thr->log, "fiber wait");
+
+ nxt_fiber_switch(thr, &fib->main->fiber);
+ nxt_unreachable();
+ }
+
+ nxt_log_debug(thr->log, "fiber wait return");
+}
+
+
+void
+nxt_fiber_exit(nxt_fiber_t *next, void *data)
+{
+ nxt_fiber_t *fib;
+ nxt_thread_t *thr;
+
+ thr = nxt_thread();
+ fib = thr->fiber;
+
+ nxt_log_debug(thr->log, "fiber exit");
+
+ /* TODO: limit idle fibers. */
+ fib->next = fib->main->idle;
+ fib->main->idle = fib;
+
+ nxt_fiber_switch(thr, next);
+ nxt_unreachable();
+}
generated by cgit (git 2.34.1) at 2024-11-18 01:48:07 +0000