diff options
Diffstat (limited to 'src/spdk/dpdk/examples/performance-thread/common/lthread.c')
-rw-r--r-- | src/spdk/dpdk/examples/performance-thread/common/lthread.c | 468 |
1 files changed, 468 insertions, 0 deletions
diff --git a/src/spdk/dpdk/examples/performance-thread/common/lthread.c b/src/spdk/dpdk/examples/performance-thread/common/lthread.c new file mode 100644 index 000000000..3f1f48db4 --- /dev/null +++ b/src/spdk/dpdk/examples/performance-thread/common/lthread.c @@ -0,0 +1,468 @@ +/* + * SPDX-License-Identifier: BSD-3-Clause + * Copyright 2015 Intel Corporation. + * Copyright 2012 Hasan Alayli <halayli@gmail.com> + */ + +#define RTE_MEM 1 + +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include <stdint.h> +#include <stddef.h> +#include <limits.h> +#include <inttypes.h> +#include <unistd.h> +#include <pthread.h> +#include <fcntl.h> +#include <sys/time.h> +#include <sys/mman.h> + +#include <rte_log.h> +#include <ctx.h> +#include <stack.h> + +#include "lthread_api.h" +#include "lthread.h" +#include "lthread_timer.h" +#include "lthread_tls.h" +#include "lthread_objcache.h" +#include "lthread_diag.h" + + +/* + * This function gets called after an lthread function has returned. + */ +void _lthread_exit_handler(struct lthread *lt) +{ + + lt->state |= BIT(ST_LT_EXITED); + + if (!(lt->state & BIT(ST_LT_DETACH))) { + /* thread is this not explicitly detached + * it must be joinable, so we call lthread_exit(). + */ + lthread_exit(NULL); + } + + /* if we get here the thread is detached so we can reschedule it, + * allowing the scheduler to free it + */ + _reschedule(); +} + + +/* + * Free resources allocated to an lthread + */ +void _lthread_free(struct lthread *lt) +{ + + DIAG_EVENT(lt, LT_DIAG_LTHREAD_FREE, lt, 0); + + /* invoke any user TLS destructor functions */ + _lthread_tls_destroy(lt); + + /* free memory allocated for TLS defined using RTE_PER_LTHREAD macros */ + if (sizeof(void *) < (uint64_t)RTE_PER_LTHREAD_SECTION_SIZE) + _lthread_objcache_free(lt->tls->root_sched->per_lthread_cache, + lt->per_lthread_data); + + /* free pthread style TLS memory */ + _lthread_objcache_free(lt->tls->root_sched->tls_cache, lt->tls); + + /* free the stack */ + _lthread_objcache_free(lt->stack_container->root_sched->stack_cache, + lt->stack_container); + + /* now free the thread */ + _lthread_objcache_free(lt->root_sched->lthread_cache, lt); + +} + +/* + * Allocate a stack and maintain a cache of stacks + */ +struct lthread_stack *_stack_alloc(void) +{ + struct lthread_stack *s; + + s = _lthread_objcache_alloc((THIS_SCHED)->stack_cache); + RTE_ASSERT(s != NULL); + + s->root_sched = THIS_SCHED; + s->stack_size = LTHREAD_MAX_STACK_SIZE; + return s; +} + +/* + * Execute a ctx by invoking the start function + * On return call an exit handler if the user has provided one + */ +static void _lthread_exec(void *arg) +{ + struct lthread *lt = (struct lthread *)arg; + + /* invoke the contexts function */ + lt->fun(lt->arg); + /* do exit handling */ + if (lt->exit_handler != NULL) + lt->exit_handler(lt); +} + +/* + * Initialize an lthread + * Set its function, args, and exit handler + */ +void +_lthread_init(struct lthread *lt, + lthread_func_t fun, void *arg, lthread_exit_func exit_handler) +{ + + /* set ctx func and args */ + lt->fun = fun; + lt->arg = arg; + lt->exit_handler = exit_handler; + + /* set initial state */ + lt->birth = _sched_now(); + lt->state = BIT(ST_LT_INIT); + lt->join = LT_JOIN_INITIAL; +} + +/* + * set the lthread stack + */ +void _lthread_set_stack(struct lthread *lt, void *stack, size_t stack_size) +{ + /* set stack */ + lt->stack = stack; + lt->stack_size = stack_size; + + arch_set_stack(lt, _lthread_exec); +} + +/* + * Create an lthread on the current scheduler + * If there is no current scheduler on this pthread then first create one + */ +int +lthread_create(struct lthread **new_lt, int lcore_id, + lthread_func_t fun, void *arg) +{ + if ((new_lt == NULL) || (fun == NULL)) + return POSIX_ERRNO(EINVAL); + + if (lcore_id < 0) + lcore_id = rte_lcore_id(); + else if (lcore_id > LTHREAD_MAX_LCORES) + return POSIX_ERRNO(EINVAL); + + struct lthread *lt = NULL; + + if (THIS_SCHED == NULL) { + THIS_SCHED = _lthread_sched_create(0); + if (THIS_SCHED == NULL) { + perror("Failed to create scheduler"); + return POSIX_ERRNO(EAGAIN); + } + } + + /* allocate a thread structure */ + lt = _lthread_objcache_alloc((THIS_SCHED)->lthread_cache); + if (lt == NULL) + return POSIX_ERRNO(EAGAIN); + + bzero(lt, sizeof(struct lthread)); + lt->root_sched = THIS_SCHED; + + /* set the function args and exit handlder */ + _lthread_init(lt, fun, arg, _lthread_exit_handler); + + /* put it in the ready queue */ + *new_lt = lt; + + if (lcore_id < 0) + lcore_id = rte_lcore_id(); + + DIAG_CREATE_EVENT(lt, LT_DIAG_LTHREAD_CREATE); + + rte_wmb(); + _ready_queue_insert(_lthread_sched_get(lcore_id), lt); + return 0; +} + +/* + * Schedules lthread to sleep for `nsecs` + * setting the lthread state to LT_ST_SLEEPING. + * lthread state is cleared upon resumption or expiry. + */ +static inline void _lthread_sched_sleep(struct lthread *lt, uint64_t nsecs) +{ + uint64_t state = lt->state; + uint64_t clks = _ns_to_clks(nsecs); + + if (clks) { + _timer_start(lt, clks); + lt->state = state | BIT(ST_LT_SLEEPING); + } + DIAG_EVENT(lt, LT_DIAG_LTHREAD_SLEEP, clks, 0); + _suspend(); +} + + + +/* + * Cancels any running timer. + * This can be called multiple times on the same lthread regardless if it was + * sleeping or not. + */ +int _lthread_desched_sleep(struct lthread *lt) +{ + uint64_t state = lt->state; + + if (state & BIT(ST_LT_SLEEPING)) { + _timer_stop(lt); + state &= (CLEARBIT(ST_LT_SLEEPING) & CLEARBIT(ST_LT_EXPIRED)); + lt->state = state | BIT(ST_LT_READY); + return 1; + } + return 0; +} + +/* + * set user data pointer in an lthread + */ +void lthread_set_data(void *data) +{ + if (sizeof(void *) == RTE_PER_LTHREAD_SECTION_SIZE) + THIS_LTHREAD->per_lthread_data = data; +} + +/* + * Retrieve user data pointer from an lthread + */ +void *lthread_get_data(void) +{ + return THIS_LTHREAD->per_lthread_data; +} + +/* + * Return the current lthread handle + */ +struct lthread *lthread_current(void) +{ + struct lthread_sched *sched = THIS_SCHED; + + if (sched) + return sched->current_lthread; + return NULL; +} + + + +/* + * Tasklet to cancel a thread + */ +static void * +_cancel(void *arg) +{ + struct lthread *lt = (struct lthread *) arg; + + lt->state |= BIT(ST_LT_CANCELLED); + lthread_detach(); + return NULL; +} + + +/* + * Mark the specified as canceled + */ +int lthread_cancel(struct lthread *cancel_lt) +{ + struct lthread *lt; + + if ((cancel_lt == NULL) || (cancel_lt == THIS_LTHREAD)) + return POSIX_ERRNO(EINVAL); + + DIAG_EVENT(cancel_lt, LT_DIAG_LTHREAD_CANCEL, cancel_lt, 0); + + if (cancel_lt->sched != THIS_SCHED) { + + /* spawn task-let to cancel the thread */ + lthread_create(<, + cancel_lt->sched->lcore_id, + _cancel, + cancel_lt); + return 0; + } + cancel_lt->state |= BIT(ST_LT_CANCELLED); + return 0; +} + +/* + * Suspend the current lthread for specified time + */ +void lthread_sleep(uint64_t nsecs) +{ + struct lthread *lt = THIS_LTHREAD; + + _lthread_sched_sleep(lt, nsecs); + +} + +/* + * Suspend the current lthread for specified time + */ +void lthread_sleep_clks(uint64_t clks) +{ + struct lthread *lt = THIS_LTHREAD; + uint64_t state = lt->state; + + if (clks) { + _timer_start(lt, clks); + lt->state = state | BIT(ST_LT_SLEEPING); + } + DIAG_EVENT(lt, LT_DIAG_LTHREAD_SLEEP, clks, 0); + _suspend(); +} + +/* + * Requeue the current thread to the back of the ready queue + */ +void lthread_yield(void) +{ + struct lthread *lt = THIS_LTHREAD; + + DIAG_EVENT(lt, LT_DIAG_LTHREAD_YIELD, 0, 0); + + _ready_queue_insert(THIS_SCHED, lt); + ctx_switch(&(THIS_SCHED)->ctx, <->ctx); +} + +/* + * Exit the current lthread + * If a thread is joining pass the user pointer to it + */ +void lthread_exit(void *ptr) +{ + struct lthread *lt = THIS_LTHREAD; + + /* if thread is detached (this is not valid) just exit */ + if (lt->state & BIT(ST_LT_DETACH)) + return; + + /* There is a race between lthread_join() and lthread_exit() + * - if exit before join then we suspend and resume on join + * - if join before exit then we resume the joining thread + */ + if ((lt->join == LT_JOIN_INITIAL) + && rte_atomic64_cmpset(<->join, LT_JOIN_INITIAL, + LT_JOIN_EXITING)) { + + DIAG_EVENT(lt, LT_DIAG_LTHREAD_EXIT, 1, 0); + _suspend(); + /* set the exit value */ + if ((ptr != NULL) && (lt->lt_join->lt_exit_ptr != NULL)) + *(lt->lt_join->lt_exit_ptr) = ptr; + + /* let the joining thread know we have set the exit value */ + lt->join = LT_JOIN_EXIT_VAL_SET; + } else { + + DIAG_EVENT(lt, LT_DIAG_LTHREAD_EXIT, 0, 0); + /* set the exit value */ + if ((ptr != NULL) && (lt->lt_join->lt_exit_ptr != NULL)) + *(lt->lt_join->lt_exit_ptr) = ptr; + /* let the joining thread know we have set the exit value */ + lt->join = LT_JOIN_EXIT_VAL_SET; + _ready_queue_insert(lt->lt_join->sched, + (struct lthread *)lt->lt_join); + } + + + /* wait until the joinging thread has collected the exit value */ + while (lt->join != LT_JOIN_EXIT_VAL_READ) + _reschedule(); + + /* reset join state */ + lt->join = LT_JOIN_INITIAL; + + /* detach it so its resources can be released */ + lt->state |= (BIT(ST_LT_DETACH) | BIT(ST_LT_EXITED)); +} + +/* + * Join an lthread + * Suspend until the joined thread returns + */ +int lthread_join(struct lthread *lt, void **ptr) +{ + if (lt == NULL) + return POSIX_ERRNO(EINVAL); + + struct lthread *current = THIS_LTHREAD; + uint64_t lt_state = lt->state; + + /* invalid to join a detached thread, or a thread that is joined */ + if ((lt_state & BIT(ST_LT_DETACH)) || (lt->join == LT_JOIN_THREAD_SET)) + return POSIX_ERRNO(EINVAL); + /* pointer to the joining thread and a poingter to return a value */ + lt->lt_join = current; + current->lt_exit_ptr = ptr; + /* There is a race between lthread_join() and lthread_exit() + * - if join before exit we suspend and will resume when exit is called + * - if exit before join we resume the exiting thread + */ + if ((lt->join == LT_JOIN_INITIAL) + && rte_atomic64_cmpset(<->join, LT_JOIN_INITIAL, + LT_JOIN_THREAD_SET)) { + + DIAG_EVENT(current, LT_DIAG_LTHREAD_JOIN, lt, 1); + _suspend(); + } else { + DIAG_EVENT(current, LT_DIAG_LTHREAD_JOIN, lt, 0); + _ready_queue_insert(lt->sched, lt); + } + + /* wait for exiting thread to set return value */ + while (lt->join != LT_JOIN_EXIT_VAL_SET) + _reschedule(); + + /* collect the return value */ + if (ptr != NULL) + *ptr = *current->lt_exit_ptr; + + /* let the exiting thread proceed to exit */ + lt->join = LT_JOIN_EXIT_VAL_READ; + return 0; +} + + +/* + * Detach current lthread + * A detached thread cannot be joined + */ +void lthread_detach(void) +{ + struct lthread *lt = THIS_LTHREAD; + + DIAG_EVENT(lt, LT_DIAG_LTHREAD_DETACH, 0, 0); + + uint64_t state = lt->state; + + lt->state = state | BIT(ST_LT_DETACH); +} + +/* + * Set function name of an lthread + * this is a debug aid + */ +void lthread_set_funcname(const char *f) +{ + struct lthread *lt = THIS_LTHREAD; + + strncpy(lt->funcname, f, sizeof(lt->funcname)); + lt->funcname[sizeof(lt->funcname)-1] = 0; +} |