diff options
Diffstat (limited to 'lib/librte_eal/linuxapp/eal/eal_interrupts.c')
| -rw-r--r-- | lib/librte_eal/linuxapp/eal/eal_interrupts.c | 1224 |
1 files changed, 1224 insertions, 0 deletions
diff --git a/lib/librte_eal/linuxapp/eal/eal_interrupts.c b/lib/librte_eal/linuxapp/eal/eal_interrupts.c new file mode 100644 index 00000000..06b26a9e --- /dev/null +++ b/lib/librte_eal/linuxapp/eal/eal_interrupts.c @@ -0,0 +1,1224 @@ +/*- + * BSD LICENSE + * + * Copyright(c) 2010-2014 Intel Corporation. All rights reserved. + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * + * * Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * * Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in + * the documentation and/or other materials provided with the + * distribution. + * * Neither the name of Intel Corporation nor the names of its + * contributors may be used to endorse or promote products derived + * from this software without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS + * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT + * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR + * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT + * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, + * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT + * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, + * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY + * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE + * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + */ + +#include <stdio.h> +#include <stdint.h> +#include <stdlib.h> +#include <pthread.h> +#include <sys/queue.h> +#include <stdarg.h> +#include <unistd.h> +#include <string.h> +#include <errno.h> +#include <inttypes.h> +#include <sys/epoll.h> +#include <sys/signalfd.h> +#include <sys/ioctl.h> +#include <sys/eventfd.h> +#include <assert.h> + +#include <rte_common.h> +#include <rte_interrupts.h> +#include <rte_memory.h> +#include <rte_memzone.h> +#include <rte_launch.h> +#include <rte_eal.h> +#include <rte_per_lcore.h> +#include <rte_lcore.h> +#include <rte_atomic.h> +#include <rte_branch_prediction.h> +#include <rte_ring.h> +#include <rte_debug.h> +#include <rte_log.h> +#include <rte_mempool.h> +#include <rte_pci.h> +#include <rte_malloc.h> +#include <rte_errno.h> +#include <rte_spinlock.h> + +#include "eal_private.h" +#include "eal_vfio.h" +#include "eal_thread.h" + +#define EAL_INTR_EPOLL_WAIT_FOREVER (-1) +#define NB_OTHER_INTR 1 + +static RTE_DEFINE_PER_LCORE(int, _epfd) = -1; /**< epoll fd per thread */ + +/** + * union for pipe fds. + */ +union intr_pipefds{ + struct { + int pipefd[2]; + }; + struct { + int readfd; + int writefd; + }; +}; + +/** + * union buffer for reading on different devices + */ +union rte_intr_read_buffer { + int uio_intr_count; /* for uio device */ +#ifdef VFIO_PRESENT + uint64_t vfio_intr_count; /* for vfio device */ +#endif + uint64_t timerfd_num; /* for timerfd */ + char charbuf[16]; /* for others */ +}; + +TAILQ_HEAD(rte_intr_cb_list, rte_intr_callback); +TAILQ_HEAD(rte_intr_source_list, rte_intr_source); + +struct rte_intr_callback { + TAILQ_ENTRY(rte_intr_callback) next; + rte_intr_callback_fn cb_fn; /**< callback address */ + void *cb_arg; /**< parameter for callback */ +}; + +struct rte_intr_source { + TAILQ_ENTRY(rte_intr_source) next; + struct rte_intr_handle intr_handle; /**< interrupt handle */ + struct rte_intr_cb_list callbacks; /**< user callbacks */ + uint32_t active; +}; + +/* global spinlock for interrupt data operation */ +static rte_spinlock_t intr_lock = RTE_SPINLOCK_INITIALIZER; + +/* union buffer for pipe read/write */ +static union intr_pipefds intr_pipe; + +/* interrupt sources list */ +static struct rte_intr_source_list intr_sources; + +/* interrupt handling thread */ +static pthread_t intr_thread; + +/* VFIO interrupts */ +#ifdef VFIO_PRESENT + +#define IRQ_SET_BUF_LEN (sizeof(struct vfio_irq_set) + sizeof(int)) +/* irq set buffer length for queue interrupts and LSC interrupt */ +#define MSIX_IRQ_SET_BUF_LEN (sizeof(struct vfio_irq_set) + \ + sizeof(int) * (RTE_MAX_RXTX_INTR_VEC_ID + 1)) + +/* enable legacy (INTx) interrupts */ +static int +vfio_enable_intx(struct rte_intr_handle *intr_handle) { + struct vfio_irq_set *irq_set; + char irq_set_buf[IRQ_SET_BUF_LEN]; + int len, ret; + int *fd_ptr; + + len = sizeof(irq_set_buf); + + /* enable INTx */ + irq_set = (struct vfio_irq_set *) irq_set_buf; + irq_set->argsz = len; + irq_set->count = 1; + irq_set->flags = VFIO_IRQ_SET_DATA_EVENTFD | VFIO_IRQ_SET_ACTION_TRIGGER; + irq_set->index = VFIO_PCI_INTX_IRQ_INDEX; + irq_set->start = 0; + fd_ptr = (int *) &irq_set->data; + *fd_ptr = intr_handle->fd; + + ret = ioctl(intr_handle->vfio_dev_fd, VFIO_DEVICE_SET_IRQS, irq_set); + + if (ret) { + RTE_LOG(ERR, EAL, "Error enabling INTx interrupts for fd %d\n", + intr_handle->fd); + return -1; + } + + /* unmask INTx after enabling */ + memset(irq_set, 0, len); + len = sizeof(struct vfio_irq_set); + irq_set->argsz = len; + irq_set->count = 1; + irq_set->flags = VFIO_IRQ_SET_DATA_NONE | VFIO_IRQ_SET_ACTION_UNMASK; + irq_set->index = VFIO_PCI_INTX_IRQ_INDEX; + irq_set->start = 0; + + ret = ioctl(intr_handle->vfio_dev_fd, VFIO_DEVICE_SET_IRQS, irq_set); + + if (ret) { + RTE_LOG(ERR, EAL, "Error unmasking INTx interrupts for fd %d\n", + intr_handle->fd); + return -1; + } + return 0; +} + +/* disable legacy (INTx) interrupts */ +static int +vfio_disable_intx(struct rte_intr_handle *intr_handle) { + struct vfio_irq_set *irq_set; + char irq_set_buf[IRQ_SET_BUF_LEN]; + int len, ret; + + len = sizeof(struct vfio_irq_set); + + /* mask interrupts before disabling */ + irq_set = (struct vfio_irq_set *) irq_set_buf; + irq_set->argsz = len; + irq_set->count = 1; + irq_set->flags = VFIO_IRQ_SET_DATA_NONE | VFIO_IRQ_SET_ACTION_UNMASK; + irq_set->index = VFIO_PCI_INTX_IRQ_INDEX; + irq_set->start = 0; + + ret = ioctl(intr_handle->vfio_dev_fd, VFIO_DEVICE_SET_IRQS, irq_set); + + if (ret) { + RTE_LOG(ERR, EAL, "Error unmasking INTx interrupts for fd %d\n", + intr_handle->fd); + return -1; + } + + /* disable INTx*/ + memset(irq_set, 0, len); + irq_set->argsz = len; + irq_set->count = 0; + irq_set->flags = VFIO_IRQ_SET_DATA_NONE | VFIO_IRQ_SET_ACTION_TRIGGER; + irq_set->index = VFIO_PCI_INTX_IRQ_INDEX; + irq_set->start = 0; + + ret = ioctl(intr_handle->vfio_dev_fd, VFIO_DEVICE_SET_IRQS, irq_set); + + if (ret) { + RTE_LOG(ERR, EAL, + "Error disabling INTx interrupts for fd %d\n", intr_handle->fd); + return -1; + } + return 0; +} + +/* enable MSI interrupts */ +static int +vfio_enable_msi(struct rte_intr_handle *intr_handle) { + int len, ret; + char irq_set_buf[IRQ_SET_BUF_LEN]; + struct vfio_irq_set *irq_set; + int *fd_ptr; + + len = sizeof(irq_set_buf); + + irq_set = (struct vfio_irq_set *) irq_set_buf; + irq_set->argsz = len; + irq_set->count = 1; + irq_set->flags = VFIO_IRQ_SET_DATA_EVENTFD | VFIO_IRQ_SET_ACTION_TRIGGER; + irq_set->index = VFIO_PCI_MSI_IRQ_INDEX; + irq_set->start = 0; + fd_ptr = (int *) &irq_set->data; + *fd_ptr = intr_handle->fd; + + ret = ioctl(intr_handle->vfio_dev_fd, VFIO_DEVICE_SET_IRQS, irq_set); + + if (ret) { + RTE_LOG(ERR, EAL, "Error enabling MSI interrupts for fd %d\n", + intr_handle->fd); + return -1; + } + return 0; +} + +/* disable MSI interrupts */ +static int +vfio_disable_msi(struct rte_intr_handle *intr_handle) { + struct vfio_irq_set *irq_set; + char irq_set_buf[IRQ_SET_BUF_LEN]; + int len, ret; + + len = sizeof(struct vfio_irq_set); + + irq_set = (struct vfio_irq_set *) irq_set_buf; + irq_set->argsz = len; + irq_set->count = 0; + irq_set->flags = VFIO_IRQ_SET_DATA_NONE | VFIO_IRQ_SET_ACTION_TRIGGER; + irq_set->index = VFIO_PCI_MSI_IRQ_INDEX; + irq_set->start = 0; + + ret = ioctl(intr_handle->vfio_dev_fd, VFIO_DEVICE_SET_IRQS, irq_set); + + if (ret) + RTE_LOG(ERR, EAL, + "Error disabling MSI interrupts for fd %d\n", intr_handle->fd); + + return ret; +} + +/* enable MSI-X interrupts */ +static int +vfio_enable_msix(struct rte_intr_handle *intr_handle) { + int len, ret; + char irq_set_buf[MSIX_IRQ_SET_BUF_LEN]; + struct vfio_irq_set *irq_set; + int *fd_ptr; + + len = sizeof(irq_set_buf); + + irq_set = (struct vfio_irq_set *) irq_set_buf; + irq_set->argsz = len; + if (!intr_handle->max_intr) + intr_handle->max_intr = 1; + else if (intr_handle->max_intr > RTE_MAX_RXTX_INTR_VEC_ID) + intr_handle->max_intr = RTE_MAX_RXTX_INTR_VEC_ID + 1; + + irq_set->count = intr_handle->max_intr; + irq_set->flags = VFIO_IRQ_SET_DATA_EVENTFD | VFIO_IRQ_SET_ACTION_TRIGGER; + irq_set->index = VFIO_PCI_MSIX_IRQ_INDEX; + irq_set->start = 0; + fd_ptr = (int *) &irq_set->data; + /* INTR vector offset 0 reserve for non-efds mapping */ + fd_ptr[RTE_INTR_VEC_ZERO_OFFSET] = intr_handle->fd; + memcpy(&fd_ptr[RTE_INTR_VEC_RXTX_OFFSET], intr_handle->efds, + sizeof(*intr_handle->efds) * intr_handle->nb_efd); + + ret = ioctl(intr_handle->vfio_dev_fd, VFIO_DEVICE_SET_IRQS, irq_set); + + if (ret) { + RTE_LOG(ERR, EAL, "Error enabling MSI-X interrupts for fd %d\n", + intr_handle->fd); + return -1; + } + + return 0; +} + +/* disable MSI-X interrupts */ +static int +vfio_disable_msix(struct rte_intr_handle *intr_handle) { + struct vfio_irq_set *irq_set; + char irq_set_buf[MSIX_IRQ_SET_BUF_LEN]; + int len, ret; + + len = sizeof(struct vfio_irq_set); + + irq_set = (struct vfio_irq_set *) irq_set_buf; + irq_set->argsz = len; + irq_set->count = 0; + irq_set->flags = VFIO_IRQ_SET_DATA_NONE | VFIO_IRQ_SET_ACTION_TRIGGER; + irq_set->index = VFIO_PCI_MSIX_IRQ_INDEX; + irq_set->start = 0; + + ret = ioctl(intr_handle->vfio_dev_fd, VFIO_DEVICE_SET_IRQS, irq_set); + + if (ret) + RTE_LOG(ERR, EAL, + "Error disabling MSI-X interrupts for fd %d\n", intr_handle->fd); + + return ret; +} +#endif + +static int +uio_intx_intr_disable(struct rte_intr_handle *intr_handle) +{ + unsigned char command_high; + + /* use UIO config file descriptor for uio_pci_generic */ + if (pread(intr_handle->uio_cfg_fd, &command_high, 1, 5) != 1) { + RTE_LOG(ERR, EAL, + "Error reading interrupts status for fd %d\n", + intr_handle->uio_cfg_fd); + return -1; + } + /* disable interrupts */ + command_high |= 0x4; + if (pwrite(intr_handle->uio_cfg_fd, &command_high, 1, 5) != 1) { + RTE_LOG(ERR, EAL, + "Error disabling interrupts for fd %d\n", + intr_handle->uio_cfg_fd); + return -1; + } + + return 0; +} + +static int +uio_intx_intr_enable(struct rte_intr_handle *intr_handle) +{ + unsigned char command_high; + + /* use UIO config file descriptor for uio_pci_generic */ + if (pread(intr_handle->uio_cfg_fd, &command_high, 1, 5) != 1) { + RTE_LOG(ERR, EAL, + "Error reading interrupts status for fd %d\n", + intr_handle->uio_cfg_fd); + return -1; + } + /* enable interrupts */ + command_high &= ~0x4; + if (pwrite(intr_handle->uio_cfg_fd, &command_high, 1, 5) != 1) { + RTE_LOG(ERR, EAL, + "Error enabling interrupts for fd %d\n", + intr_handle->uio_cfg_fd); + return -1; + } + + return 0; +} + +static int +uio_intr_disable(struct rte_intr_handle *intr_handle) +{ + const int value = 0; + + if (write(intr_handle->fd, &value, sizeof(value)) < 0) { + RTE_LOG(ERR, EAL, + "Error disabling interrupts for fd %d (%s)\n", + intr_handle->fd, strerror(errno)); + return -1; + } + return 0; +} + +static int +uio_intr_enable(struct rte_intr_handle *intr_handle) +{ + const int value = 1; + + if (write(intr_handle->fd, &value, sizeof(value)) < 0) { + RTE_LOG(ERR, EAL, + "Error enabling interrupts for fd %d (%s)\n", + intr_handle->fd, strerror(errno)); + return -1; + } + return 0; +} + +int +rte_intr_callback_register(struct rte_intr_handle *intr_handle, + rte_intr_callback_fn cb, void *cb_arg) +{ + int ret, wake_thread; + struct rte_intr_source *src; + struct rte_intr_callback *callback; + + wake_thread = 0; + + /* first do parameter checking */ + if (intr_handle == NULL || intr_handle->fd < 0 || cb == NULL) { + RTE_LOG(ERR, EAL, + "Registering with invalid input parameter\n"); + return -EINVAL; + } + + /* allocate a new interrupt callback entity */ + callback = rte_zmalloc("interrupt callback list", + sizeof(*callback), 0); + if (callback == NULL) { + RTE_LOG(ERR, EAL, "Can not allocate memory\n"); + return -ENOMEM; + } + callback->cb_fn = cb; + callback->cb_arg = cb_arg; + + rte_spinlock_lock(&intr_lock); + + /* check if there is at least one callback registered for the fd */ + TAILQ_FOREACH(src, &intr_sources, next) { + if (src->intr_handle.fd == intr_handle->fd) { + /* we had no interrupts for this */ + if TAILQ_EMPTY(&src->callbacks) + wake_thread = 1; + + TAILQ_INSERT_TAIL(&(src->callbacks), callback, next); + ret = 0; + break; + } + } + + /* no existing callbacks for this - add new source */ + if (src == NULL) { + if ((src = rte_zmalloc("interrupt source list", + sizeof(*src), 0)) == NULL) { + RTE_LOG(ERR, EAL, "Can not allocate memory\n"); + rte_free(callback); + ret = -ENOMEM; + } else { + src->intr_handle = *intr_handle; + TAILQ_INIT(&src->callbacks); + TAILQ_INSERT_TAIL(&(src->callbacks), callback, next); + TAILQ_INSERT_TAIL(&intr_sources, src, next); + wake_thread = 1; + ret = 0; + } + } + + rte_spinlock_unlock(&intr_lock); + + /** + * check if need to notify the pipe fd waited by epoll_wait to + * rebuild the wait list. + */ + if (wake_thread) + if (write(intr_pipe.writefd, "1", 1) < 0) + return -EPIPE; + + return ret; +} + +int +rte_intr_callback_unregister(struct rte_intr_handle *intr_handle, + rte_intr_callback_fn cb_fn, void *cb_arg) +{ + int ret; + struct rte_intr_source *src; + struct rte_intr_callback *cb, *next; + + /* do parameter checking first */ + if (intr_handle == NULL || intr_handle->fd < 0) { + RTE_LOG(ERR, EAL, + "Unregistering with invalid input parameter\n"); + return -EINVAL; + } + + rte_spinlock_lock(&intr_lock); + + /* check if the insterrupt source for the fd is existent */ + TAILQ_FOREACH(src, &intr_sources, next) + if (src->intr_handle.fd == intr_handle->fd) + break; + + /* No interrupt source registered for the fd */ + if (src == NULL) { + ret = -ENOENT; + + /* interrupt source has some active callbacks right now. */ + } else if (src->active != 0) { + ret = -EAGAIN; + + /* ok to remove. */ + } else { + ret = 0; + + /*walk through the callbacks and remove all that match. */ + for (cb = TAILQ_FIRST(&src->callbacks); cb != NULL; cb = next) { + + next = TAILQ_NEXT(cb, next); + + if (cb->cb_fn == cb_fn && (cb_arg == (void *)-1 || + cb->cb_arg == cb_arg)) { + TAILQ_REMOVE(&src->callbacks, cb, next); + rte_free(cb); + ret++; + } + } + + /* all callbacks for that source are removed. */ + if (TAILQ_EMPTY(&src->callbacks)) { + TAILQ_REMOVE(&intr_sources, src, next); + rte_free(src); + } + } + + rte_spinlock_unlock(&intr_lock); + + /* notify the pipe fd waited by epoll_wait to rebuild the wait list */ + if (ret >= 0 && write(intr_pipe.writefd, "1", 1) < 0) { + ret = -EPIPE; + } + + return ret; +} + +int +rte_intr_enable(struct rte_intr_handle *intr_handle) +{ + if (!intr_handle || intr_handle->fd < 0 || intr_handle->uio_cfg_fd < 0) + return -1; + + switch (intr_handle->type){ + /* write to the uio fd to enable the interrupt */ + case RTE_INTR_HANDLE_UIO: + if (uio_intr_enable(intr_handle)) + return -1; + break; + case RTE_INTR_HANDLE_UIO_INTX: + if (uio_intx_intr_enable(intr_handle)) + return -1; + break; + /* not used at this moment */ + case RTE_INTR_HANDLE_ALARM: + return -1; +#ifdef VFIO_PRESENT + case RTE_INTR_HANDLE_VFIO_MSIX: + if (vfio_enable_msix(intr_handle)) + return -1; + break; + case RTE_INTR_HANDLE_VFIO_MSI: + if (vfio_enable_msi(intr_handle)) + return -1; + break; + case RTE_INTR_HANDLE_VFIO_LEGACY: + if (vfio_enable_intx(intr_handle)) + return -1; + break; +#endif + /* unknown handle type */ + default: + RTE_LOG(ERR, EAL, + "Unknown handle type of fd %d\n", + intr_handle->fd); + return -1; + } + + return 0; +} + +int +rte_intr_disable(struct rte_intr_handle *intr_handle) +{ + if (!intr_handle || intr_handle->fd < 0 || intr_handle->uio_cfg_fd < 0) + return -1; + + switch (intr_handle->type){ + /* write to the uio fd to disable the interrupt */ + case RTE_INTR_HANDLE_UIO: + if (uio_intr_disable(intr_handle)) + return -1; + break; + case RTE_INTR_HANDLE_UIO_INTX: + if (uio_intx_intr_disable(intr_handle)) + return -1; + break; + /* not used at this moment */ + case RTE_INTR_HANDLE_ALARM: + return -1; +#ifdef VFIO_PRESENT + case RTE_INTR_HANDLE_VFIO_MSIX: + if (vfio_disable_msix(intr_handle)) + return -1; + break; + case RTE_INTR_HANDLE_VFIO_MSI: + if (vfio_disable_msi(intr_handle)) + return -1; + break; + case RTE_INTR_HANDLE_VFIO_LEGACY: + if (vfio_disable_intx(intr_handle)) + return -1; + break; +#endif + /* unknown handle type */ + default: + RTE_LOG(ERR, EAL, + "Unknown handle type of fd %d\n", + intr_handle->fd); + return -1; + } + + return 0; +} + +static int +eal_intr_process_interrupts(struct epoll_event *events, int nfds) +{ + int n, bytes_read; + struct rte_intr_source *src; + struct rte_intr_callback *cb; + union rte_intr_read_buffer buf; + struct rte_intr_callback active_cb; + + for (n = 0; n < nfds; n++) { + + /** + * if the pipe fd is ready to read, return out to + * rebuild the wait list. + */ + if (events[n].data.fd == intr_pipe.readfd){ + int r = read(intr_pipe.readfd, buf.charbuf, + sizeof(buf.charbuf)); + RTE_SET_USED(r); + return -1; + } + rte_spinlock_lock(&intr_lock); + TAILQ_FOREACH(src, &intr_sources, next) + if (src->intr_handle.fd == + events[n].data.fd) + break; + if (src == NULL){ + rte_spinlock_unlock(&intr_lock); + continue; + } + + /* mark this interrupt source as active and release the lock. */ + src->active = 1; + rte_spinlock_unlock(&intr_lock); + + /* set the length to be read dor different handle type */ + switch (src->intr_handle.type) { + case RTE_INTR_HANDLE_UIO: + case RTE_INTR_HANDLE_UIO_INTX: + bytes_read = sizeof(buf.uio_intr_count); + break; + case RTE_INTR_HANDLE_ALARM: + bytes_read = sizeof(buf.timerfd_num); + break; +#ifdef VFIO_PRESENT + case RTE_INTR_HANDLE_VFIO_MSIX: + case RTE_INTR_HANDLE_VFIO_MSI: + case RTE_INTR_HANDLE_VFIO_LEGACY: + bytes_read = sizeof(buf.vfio_intr_count); + break; +#endif + case RTE_INTR_HANDLE_EXT: + default: + bytes_read = 1; + break; + } + + if (src->intr_handle.type != RTE_INTR_HANDLE_EXT) { + /** + * read out to clear the ready-to-be-read flag + * for epoll_wait. + */ + bytes_read = read(events[n].data.fd, &buf, bytes_read); + if (bytes_read < 0) { + if (errno == EINTR || errno == EWOULDBLOCK) + continue; + + RTE_LOG(ERR, EAL, "Error reading from file " + "descriptor %d: %s\n", + events[n].data.fd, + strerror(errno)); + } else if (bytes_read == 0) + RTE_LOG(ERR, EAL, "Read nothing from file " + "descriptor %d\n", events[n].data.fd); + } + + /* grab a lock, again to call callbacks and update status. */ + rte_spinlock_lock(&intr_lock); + + if (bytes_read > 0) { + + /* Finally, call all callbacks. */ + TAILQ_FOREACH(cb, &src->callbacks, next) { + + /* make a copy and unlock. */ + active_cb = *cb; + rte_spinlock_unlock(&intr_lock); + + /* call the actual callback */ + active_cb.cb_fn(&src->intr_handle, + active_cb.cb_arg); + + /*get the lock back. */ + rte_spinlock_lock(&intr_lock); + } + } + + /* we done with that interrupt source, release it. */ + src->active = 0; + rte_spinlock_unlock(&intr_lock); + } + + return 0; +} + +/** + * It handles all the interrupts. + * + * @param pfd + * epoll file descriptor. + * @param totalfds + * The number of file descriptors added in epoll. + * + * @return + * void + */ +static void +eal_intr_handle_interrupts(int pfd, unsigned totalfds) +{ + struct epoll_event events[totalfds]; + int nfds = 0; + + for(;;) { + nfds = epoll_wait(pfd, events, totalfds, + EAL_INTR_EPOLL_WAIT_FOREVER); + /* epoll_wait fail */ + if (nfds < 0) { + if (errno == EINTR) + continue; + RTE_LOG(ERR, EAL, + "epoll_wait returns with fail\n"); + return; + } + /* epoll_wait timeout, will never happens here */ + else if (nfds == 0) + continue; + /* epoll_wait has at least one fd ready to read */ + if (eal_intr_process_interrupts(events, nfds) < 0) + return; + } +} + +/** + * It builds/rebuilds up the epoll file descriptor with all the + * file descriptors being waited on. Then handles the interrupts. + * + * @param arg + * pointer. (unused) + * + * @return + * never return; + */ +static __attribute__((noreturn)) void * +eal_intr_thread_main(__rte_unused void *arg) +{ + struct epoll_event ev; + + /* host thread, never break out */ + for (;;) { + /* build up the epoll fd with all descriptors we are to + * wait on then pass it to the handle_interrupts function + */ + static struct epoll_event pipe_event = { + .events = EPOLLIN | EPOLLPRI, + }; + struct rte_intr_source *src; + unsigned numfds = 0; + + /* create epoll fd */ + int pfd = epoll_create(1); + if (pfd < 0) + rte_panic("Cannot create epoll instance\n"); + + pipe_event.data.fd = intr_pipe.readfd; + /** + * add pipe fd into wait list, this pipe is used to + * rebuild the wait list. + */ + if (epoll_ctl(pfd, EPOLL_CTL_ADD, intr_pipe.readfd, + &pipe_event) < 0) { + rte_panic("Error adding fd to %d epoll_ctl, %s\n", + intr_pipe.readfd, strerror(errno)); + } + numfds++; + + rte_spinlock_lock(&intr_lock); + + TAILQ_FOREACH(src, &intr_sources, next) { + if (src->callbacks.tqh_first == NULL) + continue; /* skip those with no callbacks */ + ev.events = EPOLLIN | EPOLLPRI; + ev.data.fd = src->intr_handle.fd; + + /** + * add all the uio device file descriptor + * into wait list. + */ + if (epoll_ctl(pfd, EPOLL_CTL_ADD, + src->intr_handle.fd, &ev) < 0){ + rte_panic("Error adding fd %d epoll_ctl, %s\n", + src->intr_handle.fd, strerror(errno)); + } + else + numfds++; + } + rte_spinlock_unlock(&intr_lock); + /* serve the interrupt */ + eal_intr_handle_interrupts(pfd, numfds); + + /** + * when we return, we need to rebuild the + * list of fds to monitor. + */ + close(pfd); + } +} + +int +rte_eal_intr_init(void) +{ + int ret = 0, ret_1 = 0; + char thread_name[RTE_MAX_THREAD_NAME_LEN]; + + /* init the global interrupt source head */ + TAILQ_INIT(&intr_sources); + + /** + * create a pipe which will be waited by epoll and notified to + * rebuild the wait list of epoll. + */ + if (pipe(intr_pipe.pipefd) < 0) + return -1; + + /* create the host thread to wait/handle the interrupt */ + ret = pthread_create(&intr_thread, NULL, + eal_intr_thread_main, NULL); + if (ret != 0) { + RTE_LOG(ERR, EAL, + "Failed to create thread for interrupt handling\n"); + } else { + /* Set thread_name for aid in debugging. */ + snprintf(thread_name, RTE_MAX_THREAD_NAME_LEN, + "eal-intr-thread"); + ret_1 = rte_thread_setname(intr_thread, thread_name); + if (ret_1 != 0) + RTE_LOG(ERR, EAL, + "Failed to set thread name for interrupt handling\n"); + } + + return -ret; +} + +static void +eal_intr_proc_rxtx_intr(int fd, const struct rte_intr_handle *intr_handle) +{ + union rte_intr_read_buffer buf; + int bytes_read = 1; + int nbytes; + + switch (intr_handle->type) { + case RTE_INTR_HANDLE_UIO: + case RTE_INTR_HANDLE_UIO_INTX: + bytes_read = sizeof(buf.uio_intr_count); + break; +#ifdef VFIO_PRESENT + case RTE_INTR_HANDLE_VFIO_MSIX: + case RTE_INTR_HANDLE_VFIO_MSI: + case RTE_INTR_HANDLE_VFIO_LEGACY: + bytes_read = sizeof(buf.vfio_intr_count); + break; +#endif + default: + bytes_read = 1; + RTE_LOG(INFO, EAL, "unexpected intr type\n"); + break; + } + + /** + * read out to clear the ready-to-be-read flag + * for epoll_wait. + */ + do { + nbytes = read(fd, &buf, bytes_read); + if (nbytes < 0) { + if (errno == EINTR || errno == EWOULDBLOCK || + errno == EAGAIN) + continue; + RTE_LOG(ERR, EAL, + "Error reading from fd %d: %s\n", + fd, strerror(errno)); + } else if (nbytes == 0) + RTE_LOG(ERR, EAL, "Read nothing from fd %d\n", fd); + return; + } while (1); +} + +static int +eal_epoll_process_event(struct epoll_event *evs, unsigned int n, + struct rte_epoll_event *events) +{ + unsigned int i, count = 0; + struct rte_epoll_event *rev; + + for (i = 0; i < n; i++) { + rev = evs[i].data.ptr; + if (!rev || !rte_atomic32_cmpset(&rev->status, RTE_EPOLL_VALID, + RTE_EPOLL_EXEC)) + continue; + + events[count].status = RTE_EPOLL_VALID; + events[count].fd = rev->fd; + events[count].epfd = rev->epfd; + events[count].epdata.event = rev->epdata.event; + events[count].epdata.data = rev->epdata.data; + if (rev->epdata.cb_fun) + rev->epdata.cb_fun(rev->fd, + rev->epdata.cb_arg); + + rte_compiler_barrier(); + rev->status = RTE_EPOLL_VALID; + count++; + } + return count; +} + +static inline int +eal_init_tls_epfd(void) +{ + int pfd = epoll_create(255); + + if (pfd < 0) { + RTE_LOG(ERR, EAL, + "Cannot create epoll instance\n"); + return -1; + } + return pfd; +} + +int +rte_intr_tls_epfd(void) +{ + if (RTE_PER_LCORE(_epfd) == -1) + RTE_PER_LCORE(_epfd) = eal_init_tls_epfd(); + + return RTE_PER_LCORE(_epfd); +} + +int +rte_epoll_wait(int epfd, struct rte_epoll_event *events, + int maxevents, int timeout) +{ + struct epoll_event evs[maxevents]; + int rc; + + if (!events) { + RTE_LOG(ERR, EAL, "rte_epoll_event can't be NULL\n"); + return -1; + } + + /* using per thread epoll fd */ + if (epfd == RTE_EPOLL_PER_THREAD) + epfd = rte_intr_tls_epfd(); + + while (1) { + rc = epoll_wait(epfd, evs, maxevents, timeout); + if (likely(rc > 0)) { + /* epoll_wait has at least one fd ready to read */ + rc = eal_epoll_process_event(evs, rc, events); + break; + } else if (rc < 0) { + if (errno == EINTR) + continue; + /* epoll_wait fail */ + RTE_LOG(ERR, EAL, "epoll_wait returns with fail %s\n", + strerror(errno)); + rc = -1; + break; + } else { + /* rc == 0, epoll_wait timed out */ + break; + } + } + + return rc; +} + +static inline void +eal_epoll_data_safe_free(struct rte_epoll_event *ev) +{ + while (!rte_atomic32_cmpset(&ev->status, RTE_EPOLL_VALID, + RTE_EPOLL_INVALID)) + while (ev->status != RTE_EPOLL_VALID) + rte_pause(); + memset(&ev->epdata, 0, sizeof(ev->epdata)); + ev->fd = -1; + ev->epfd = -1; +} + +int +rte_epoll_ctl(int epfd, int op, int fd, + struct rte_epoll_event *event) +{ + struct epoll_event ev; + + if (!event) { + RTE_LOG(ERR, EAL, "rte_epoll_event can't be NULL\n"); + return -1; + } + + /* using per thread epoll fd */ + if (epfd == RTE_EPOLL_PER_THREAD) + epfd = rte_intr_tls_epfd(); + + if (op == EPOLL_CTL_ADD) { + event->status = RTE_EPOLL_VALID; + event->fd = fd; /* ignore fd in event */ + event->epfd = epfd; + ev.data.ptr = (void *)event; + } + + ev.events = event->epdata.event; + if (epoll_ctl(epfd, op, fd, &ev) < 0) { + RTE_LOG(ERR, EAL, "Error op %d fd %d epoll_ctl, %s\n", + op, fd, strerror(errno)); + if (op == EPOLL_CTL_ADD) + /* rollback status when CTL_ADD fail */ + event->status = RTE_EPOLL_INVALID; + return -1; + } + + if (op == EPOLL_CTL_DEL && event->status != RTE_EPOLL_INVALID) + eal_epoll_data_safe_free(event); + + return 0; +} + +int +rte_intr_rx_ctl(struct rte_intr_handle *intr_handle, int epfd, + int op, unsigned int vec, void *data) +{ + struct rte_epoll_event *rev; + struct rte_epoll_data *epdata; + int epfd_op; + unsigned int efd_idx; + int rc = 0; + + efd_idx = (vec >= RTE_INTR_VEC_RXTX_OFFSET) ? + (vec - RTE_INTR_VEC_RXTX_OFFSET) : vec; + + if (!intr_handle || intr_handle->nb_efd == 0 || + efd_idx >= intr_handle->nb_efd) { + RTE_LOG(ERR, EAL, "Wrong intr vector number.\n"); + return -EPERM; + } + + switch (op) { + case RTE_INTR_EVENT_ADD: + epfd_op = EPOLL_CTL_ADD; + rev = &intr_handle->elist[efd_idx]; + if (rev->status != RTE_EPOLL_INVALID) { + RTE_LOG(INFO, EAL, "Event already been added.\n"); + return -EEXIST; + } + + /* attach to intr vector fd */ + epdata = &rev->epdata; + epdata->event = EPOLLIN | EPOLLPRI | EPOLLET; + epdata->data = data; + epdata->cb_fun = (rte_intr_event_cb_t)eal_intr_proc_rxtx_intr; + epdata->cb_arg = (void *)intr_handle; + rc = rte_epoll_ctl(epfd, epfd_op, + intr_handle->efds[efd_idx], rev); + if (!rc) + RTE_LOG(DEBUG, EAL, + "efd %d associated with vec %d added on epfd %d" + "\n", rev->fd, vec, epfd); + else + rc = -EPERM; + break; + case RTE_INTR_EVENT_DEL: + epfd_op = EPOLL_CTL_DEL; + rev = &intr_handle->elist[efd_idx]; + if (rev->status == RTE_EPOLL_INVALID) { + RTE_LOG(INFO, EAL, "Event does not exist.\n"); + return -EPERM; + } + + rc = rte_epoll_ctl(rev->epfd, epfd_op, rev->fd, rev); + if (rc) + rc = -EPERM; + break; + default: + RTE_LOG(ERR, EAL, "event op type mismatch\n"); + rc = -EPERM; + } + + return rc; +} + +int +rte_intr_efd_enable(struct rte_intr_handle *intr_handle, uint32_t nb_efd) +{ + uint32_t i; + int fd; + uint32_t n = RTE_MIN(nb_efd, (uint32_t)RTE_MAX_RXTX_INTR_VEC_ID); + + assert(nb_efd != 0); + + if (intr_handle->type == RTE_INTR_HANDLE_VFIO_MSIX) { + for (i = 0; i < n; i++) { + fd = eventfd(0, EFD_NONBLOCK | EFD_CLOEXEC); + if (fd < 0) { + RTE_LOG(ERR, EAL, + "can't setup eventfd, error %i (%s)\n", + errno, strerror(errno)); + return -1; + } + intr_handle->efds[i] = fd; + } + intr_handle->nb_efd = n; + intr_handle->max_intr = NB_OTHER_INTR + n; + } else { + intr_handle->efds[0] = intr_handle->fd; + intr_handle->nb_efd = RTE_MIN(nb_efd, 1U); + intr_handle->max_intr = NB_OTHER_INTR; + } + + return 0; +} + +void +rte_intr_efd_disable(struct rte_intr_handle *intr_handle) +{ + uint32_t i; + struct rte_epoll_event *rev; + + for (i = 0; i < intr_handle->nb_efd; i++) { + rev = &intr_handle->elist[i]; + if (rev->status == RTE_EPOLL_INVALID) + continue; + if (rte_epoll_ctl(rev->epfd, EPOLL_CTL_DEL, rev->fd, rev)) { + /* force free if the entry valid */ + eal_epoll_data_safe_free(rev); + rev->status = RTE_EPOLL_INVALID; + } + } + + if (intr_handle->max_intr > intr_handle->nb_efd) { + for (i = 0; i < intr_handle->nb_efd; i++) + close(intr_handle->efds[i]); + } + intr_handle->nb_efd = 0; + intr_handle->max_intr = 0; +} + +int +rte_intr_dp_is_en(struct rte_intr_handle *intr_handle) +{ + return !(!intr_handle->nb_efd); +} + +int +rte_intr_allow_others(struct rte_intr_handle *intr_handle) +{ + if (!rte_intr_dp_is_en(intr_handle)) + return 1; + else + return !!(intr_handle->max_intr - intr_handle->nb_efd); +} + +int +rte_intr_cap_multiple(struct rte_intr_handle *intr_handle) +{ + if (intr_handle->type == RTE_INTR_HANDLE_VFIO_MSIX) + return 1; + + return 0; +} |