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Diffstat (limited to 'lib/librte_eal/linuxapp/eal/eal_interrupts.c')
-rw-r--r--lib/librte_eal/linuxapp/eal/eal_interrupts.c540
1 files changed, 540 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 0000000..8ff2289
--- /dev/null
+++ b/lib/librte_eal/linuxapp/eal/eal_interrupts.c
@@ -0,0 +1,540 @@
+/*-
+ * BSD LICENSE
+ *
+ * Copyright(c) 2010-2012 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.
+ *
+ * version: DPDK.L.1.2.3-3
+ */
+
+#include <stdio.h>
+#include <stdint.h>
+#include <stdlib.h>
+#include <pthread.h>
+#include <sys/queue.h>
+#include <malloc.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 <rte_common.h>
+#include <rte_interrupts.h>
+#include <rte_memory.h>
+#include <rte_memzone.h>
+#include <rte_launch.h>
+#include <rte_tailq.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"
+
+#define EAL_INTR_EPOLL_WAIT_FOREVER (-1)
+
+/**
+ * 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 */
+ 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 */
+};
+
+/* 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;
+
+int
+rte_intr_callback_register(struct rte_intr_handle *intr_handle,
+ rte_intr_callback_fn cb, void *cb_arg)
+{
+ int ret = -1;
+ struct rte_intr_source *src;
+ int 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 */
+ struct rte_intr_callback *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) {
+ if (src->callbacks.tqh_first == NULL)
+ /* we had no interrupts for this */
+ wake_thread = 1;
+
+ TAILQ_INSERT_TAIL(&(src->callbacks), callback, next);
+ break;
+ }
+
+ /* No callback registered for this fd */
+ if (src == NULL){
+ /* no existing callbacks for this - add new source */
+ src = rte_zmalloc("interrupt source list", sizeof(*src), 0);
+ if (src == NULL){
+ RTE_LOG(ERR, EAL, "Can not allocate memory\n");
+ ret = -ENOMEM;
+ goto error;
+ }
+ src->intr_handle = *intr_handle;
+ TAILQ_INIT(&src->callbacks);
+
+ TAILQ_INSERT_TAIL(&intr_sources, src, next);
+ TAILQ_INSERT_TAIL(&(src->callbacks), callback, next);
+ wake_thread = 1;
+ }
+
+ 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 0;
+
+error:
+ rte_spinlock_unlock(&intr_lock);
+
+ return ret;
+}
+
+int
+rte_intr_callback_unregister(struct rte_intr_handle *intr_handle,
+ rte_intr_callback_fn cb_fn, void *cb_arg)
+{
+ int ret = -1;
+ struct rte_intr_source *src;
+ struct rte_intr_callback *cb;
+
+ /* 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;
+ goto error;
+ }
+
+ ret = 0;
+ TAILQ_FOREACH(cb, &src->callbacks, next) {
+ if (cb->cb_fn != cb_fn)
+ continue;
+ if (cb_arg == (void *)-1 || cb->cb_arg == cb_arg) {
+ TAILQ_REMOVE(&src->callbacks, cb, next);
+ rte_free(cb);
+ ret ++;
+ }
+
+ if (src->callbacks.tqh_first == NULL) {
+ TAILQ_REMOVE(&intr_sources, src, next);
+ rte_free(src);
+ }
+ }
+
+ /* notify the pipe fd waited by epoll_wait to rebuild the wait list */
+ if (write(intr_pipe.writefd, "1", 1) < 0) {
+ ret = -EPIPE;
+ goto error;
+ }
+
+ rte_spinlock_unlock(&intr_lock);
+
+ return ret;
+
+error:
+ rte_spinlock_unlock(&intr_lock);
+
+ return ret;
+}
+
+int
+rte_intr_enable(struct rte_intr_handle *intr_handle)
+{
+ const int value = 1;
+
+ if (!intr_handle || intr_handle->fd < 0)
+ return -1;
+
+ switch (intr_handle->type){
+ /* write to the uio fd to enable the interrupt */
+ case RTE_INTR_HANDLE_UIO:
+ if (write(intr_handle->fd, &value, sizeof(value)) < 0) {
+ RTE_LOG(ERR, EAL,
+ "Error enabling interrupts for fd %d\n",
+ intr_handle->fd);
+ return -1;
+ }
+ break;
+ /* not used at this moment */
+ case RTE_INTR_HANDLE_ALARM:
+ return -1;
+ /* unkown 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)
+{
+ const int value = 0;
+
+ if (!intr_handle || intr_handle->fd < 0)
+ return -1;
+
+ switch (intr_handle->type){
+ /* write to the uio fd to disable the interrupt */
+ case RTE_INTR_HANDLE_UIO:
+ if (write(intr_handle->fd, &value, sizeof(value)) < 0){
+ RTE_LOG(ERR, EAL,
+ "Error enabling interrupts for fd %d\n",
+ intr_handle->fd);
+ return -1;
+ }
+ break;
+ /* not used at this moment */
+ case RTE_INTR_HANDLE_ALARM:
+ return -1;
+ /* unkown 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, i, active_cb, bytes_read;
+ struct rte_intr_source *src;
+ struct rte_intr_callback *cb;
+ union rte_intr_read_buffer buf;
+ struct rte_intr_callback active_cbs[32];
+
+ 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;
+ }
+
+ /* for this source, make a copy of all the callbacks,
+ * then unlock the lock, so the callbacks can
+ * themselves manipulate the list for future
+ * instances.
+ */
+ active_cb = 0;
+ memset(active_cbs, 0, sizeof(active_cbs));
+ TAILQ_FOREACH(cb, &src->callbacks, next)
+ active_cbs[active_cb++] = *cb;
+ 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:
+ bytes_read = 4;
+ break;
+ case RTE_INTR_HANDLE_ALARM:
+ bytes_read = sizeof(uint64_t);
+ break;
+ default:
+ bytes_read = 1;
+ break;
+ }
+ /**
+ * 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) {
+ RTE_LOG(ERR, EAL, "Error reading from file descriptor"
+ " %d, error: %d\n", events[n].data.fd, errno);
+ continue;
+ }
+ else if (bytes_read == 0) {
+ RTE_LOG(ERR, EAL,
+ "Read nothing from file descriptor %d.\n",
+ events[n].data.fd);
+ continue;
+ }
+ /**
+ * Finally, call all callbacks from the copy
+ * we made earlier.
+ */
+ for (i = 0; i < active_cb; i++) {
+ if (active_cbs[i].cb_fn == NULL)
+ continue;
+ active_cbs[i].cb_fn(&src->intr_handle,
+ active_cbs[i].cb_arg);
+ }
+ }
+
+ 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;
+
+ /* 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");
+
+ return -ret;
+}
+