--- /dev/null
+/*
+ * Copyright (C) 2011 - David Goulet <david.goulet@polymtl.ca>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; only version 2
+ * of the License.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ */
+
+#define _GNU_SOURCE
+#include <errno.h>
+#include <fcntl.h>
+#include <stdlib.h>
+#include <stdio.h>
+#include <string.h>
+#include <unistd.h>
+
+#include <lttng-kernel-ctl.h>
+#include <lttngerr.h>
+
+#include "kernel.h"
+
+/*
+ * Add context on a kernel channel.
+ */
+int kernel_add_channel_context(struct ltt_kernel_channel *chan,
+ struct lttng_kernel_context *ctx)
+{
+ int ret;
+
+ DBG("Adding context to channel %s", chan->channel->name);
+ ret = kernctl_add_context(chan->fd, ctx);
+ if (ret < 0) {
+ if (errno != EEXIST) {
+ perror("add context ioctl");
+ } else {
+ /* If EEXIST, we just ignore the error */
+ ret = 0;
+ }
+ goto error;
+ }
+
+ chan->ctx = zmalloc(sizeof(struct lttng_kernel_context));
+ if (chan->ctx == NULL) {
+ perror("zmalloc event context");
+ goto error;
+ }
+
+ memcpy(chan->ctx, ctx, sizeof(struct lttng_kernel_context));
+
+ return 0;
+
+error:
+ return ret;
+}
+
+/*
+ * Add context on a kernel event.
+ */
+int kernel_add_event_context(struct ltt_kernel_event *event,
+ struct lttng_kernel_context *ctx)
+{
+ int ret;
+
+ DBG("Adding context to event %s", event->event->name);
+ ret = kernctl_add_context(event->fd, ctx);
+ if (ret < 0) {
+ perror("add context ioctl");
+ goto error;
+ }
+
+ event->ctx = zmalloc(sizeof(struct lttng_kernel_context));
+ if (event->ctx == NULL) {
+ perror("zmalloc event context");
+ goto error;
+ }
+
+ memcpy(event->ctx, ctx, sizeof(struct lttng_kernel_context));
+
+ return 0;
+
+error:
+ return ret;
+}
+
+/*
+ * Create a new kernel session, register it to the kernel tracer and add it to
+ * the session daemon session.
+ */
+int kernel_create_session(struct ltt_session *session, int tracer_fd)
+{
+ int ret;
+ struct ltt_kernel_session *lks;
+
+ /* Allocate data structure */
+ lks = trace_kernel_create_session(session->path);
+ if (lks == NULL) {
+ ret = -1;
+ goto error;
+ }
+
+ /* Kernel tracer session creation */
+ ret = kernctl_create_session(tracer_fd);
+ if (ret < 0) {
+ perror("ioctl kernel create session");
+ goto error;
+ }
+
+ lks->fd = ret;
+ /* Prevent fd duplication after execlp() */
+ ret = fcntl(lks->fd, F_SETFD, FD_CLOEXEC);
+ if (ret < 0) {
+ perror("fcntl session fd");
+ }
+
+ lks->consumer_fds_sent = 0;
+ session->kernel_session = lks;
+
+ DBG("Kernel session created (fd: %d)", lks->fd);
+
+ return 0;
+
+error:
+ return ret;
+}
+
+/*
+ * Create a kernel channel, register it to the kernel tracer and add it to the
+ * kernel session.
+ */
+int kernel_create_channel(struct ltt_kernel_session *session,
+ struct lttng_channel *chan, char *path)
+{
+ int ret;
+ struct ltt_kernel_channel *lkc;
+
+ /* Allocate kernel channel */
+ lkc = trace_kernel_create_channel(chan, path);
+ if (lkc == NULL) {
+ goto error;
+ }
+
+ /* Kernel tracer channel creation */
+ ret = kernctl_create_channel(session->fd, &lkc->channel->attr);
+ if (ret < 0) {
+ perror("ioctl kernel create channel");
+ goto error;
+ }
+
+ /* Setup the channel fd */
+ lkc->fd = ret;
+ /* Prevent fd duplication after execlp() */
+ ret = fcntl(lkc->fd, F_SETFD, FD_CLOEXEC);
+ if (ret < 0) {
+ perror("fcntl session fd");
+ }
+
+ /* Add channel to session */
+ cds_list_add(&lkc->list, &session->channel_list.head);
+ session->channel_count++;
+
+ DBG("Kernel channel %s created (fd: %d and path: %s)",
+ lkc->channel->name, lkc->fd, lkc->pathname);
+
+ return 0;
+
+error:
+ return -1;
+}
+
+/*
+ * Create a kernel event, enable it to the kernel tracer and add it to the
+ * channel event list of the kernel session.
+ */
+int kernel_create_event(struct lttng_event *ev,
+ struct ltt_kernel_channel *channel)
+{
+ int ret;
+ struct ltt_kernel_event *event;
+
+ event = trace_kernel_create_event(ev);
+ if (event == NULL) {
+ ret = -1;
+ goto error;
+ }
+
+ ret = kernctl_create_event(channel->fd, event->event);
+ if (ret < 0) {
+ if (errno != EEXIST) {
+ PERROR("create event ioctl");
+ }
+ ret = -errno;
+ goto free_event;
+ }
+
+ /*
+ * LTTNG_KERNEL_SYSCALL event creation will return 0 on success. However
+ * this FD must not be added to the event list.
+ */
+ if (ret == 0 && event->event->instrumentation == LTTNG_KERNEL_SYSCALL) {
+ DBG2("Kernel event syscall creation success");
+ goto end;
+ }
+
+ event->fd = ret;
+ /* Prevent fd duplication after execlp() */
+ ret = fcntl(event->fd, F_SETFD, FD_CLOEXEC);
+ if (ret < 0) {
+ perror("fcntl session fd");
+ }
+
+ /* Add event to event list */
+ cds_list_add(&event->list, &channel->events_list.head);
+ channel->event_count++;
+
+ DBG("Event %s created (fd: %d)", ev->name, event->fd);
+
+end:
+ return 0;
+
+free_event:
+ free(event);
+error:
+ return ret;
+}
+
+/*
+ * Disable a kernel channel.
+ */
+int kernel_disable_channel(struct ltt_kernel_channel *chan)
+{
+ int ret;
+
+ ret = kernctl_disable(chan->fd);
+ if (ret < 0) {
+ perror("disable chan ioctl");
+ ret = errno;
+ goto error;
+ }
+
+ chan->enabled = 0;
+ DBG("Kernel channel %s disabled (fd: %d)", chan->channel->name, chan->fd);
+
+ return 0;
+
+error:
+ return ret;
+}
+
+/*
+ * Enable a kernel channel.
+ */
+int kernel_enable_channel(struct ltt_kernel_channel *chan)
+{
+ int ret;
+
+ ret = kernctl_enable(chan->fd);
+ if (ret < 0 && errno != EEXIST) {
+ perror("Enable kernel chan");
+ goto error;
+ }
+
+ chan->enabled = 1;
+ DBG("Kernel channel %s enabled (fd: %d)", chan->channel->name, chan->fd);
+
+ return 0;
+
+error:
+ return ret;
+}
+
+/*
+ * Enable a kernel event.
+ */
+int kernel_enable_event(struct ltt_kernel_event *event)
+{
+ int ret;
+
+ ret = kernctl_enable(event->fd);
+ if (ret < 0 && errno != EEXIST) {
+ perror("enable kernel event");
+ goto error;
+ }
+
+ event->enabled = 1;
+ DBG("Kernel event %s enabled (fd: %d)", event->event->name, event->fd);
+
+ return 0;
+
+error:
+ return ret;
+}
+
+/*
+ * Disable a kernel event.
+ */
+int kernel_disable_event(struct ltt_kernel_event *event)
+{
+ int ret;
+
+ ret = kernctl_disable(event->fd);
+ if (ret < 0 && errno != EEXIST) {
+ perror("disable kernel event");
+ goto error;
+ }
+
+ event->enabled = 0;
+ DBG("Kernel event %s disabled (fd: %d)", event->event->name, event->fd);
+
+ return 0;
+
+error:
+ return ret;
+}
+
+/*
+ * Create kernel metadata, open from the kernel tracer and add it to the
+ * kernel session.
+ */
+int kernel_open_metadata(struct ltt_kernel_session *session, char *path)
+{
+ int ret;
+ struct ltt_kernel_metadata *lkm;
+
+ /* Allocate kernel metadata */
+ lkm = trace_kernel_create_metadata(path);
+ if (lkm == NULL) {
+ goto error;
+ }
+
+ /* Kernel tracer metadata creation */
+ ret = kernctl_open_metadata(session->fd, &lkm->conf->attr);
+ if (ret < 0) {
+ goto error;
+ }
+
+ lkm->fd = ret;
+ /* Prevent fd duplication after execlp() */
+ ret = fcntl(lkm->fd, F_SETFD, FD_CLOEXEC);
+ if (ret < 0) {
+ perror("fcntl session fd");
+ }
+
+ session->metadata = lkm;
+
+ DBG("Kernel metadata opened (fd: %d and path: %s)", lkm->fd, lkm->pathname);
+
+ return 0;
+
+error:
+ return -1;
+}
+
+/*
+ * Start tracing session.
+ */
+int kernel_start_session(struct ltt_kernel_session *session)
+{
+ int ret;
+
+ ret = kernctl_start_session(session->fd);
+ if (ret < 0) {
+ perror("ioctl start session");
+ goto error;
+ }
+
+ DBG("Kernel session started");
+
+ return 0;
+
+error:
+ return ret;
+}
+
+/*
+ * Make a kernel wait to make sure in-flight probe have completed.
+ */
+void kernel_wait_quiescent(int fd)
+{
+ int ret;
+
+ DBG("Kernel quiescent wait on %d", fd);
+
+ ret = kernctl_wait_quiescent(fd);
+ if (ret < 0) {
+ perror("wait quiescent ioctl");
+ ERR("Kernel quiescent wait failed");
+ }
+}
+
+/*
+ * Kernel calibrate
+ */
+int kernel_calibrate(int fd, struct lttng_kernel_calibrate *calibrate)
+{
+ int ret;
+
+ ret = kernctl_calibrate(fd, calibrate);
+ if (ret < 0) {
+ perror("calibrate ioctl");
+ return -1;
+ }
+
+ return 0;
+}
+
+
+/*
+ * Force flush buffer of metadata.
+ */
+int kernel_metadata_flush_buffer(int fd)
+{
+ int ret;
+
+ ret = kernctl_buffer_flush(fd);
+ if (ret < 0) {
+ ERR("Fail to flush metadata buffers %d (ret: %d", fd, ret);
+ }
+
+ return 0;
+}
+
+/*
+ * Force flush buffer for channel.
+ */
+int kernel_flush_buffer(struct ltt_kernel_channel *channel)
+{
+ int ret;
+ struct ltt_kernel_stream *stream;
+
+ DBG("Flush buffer for channel %s", channel->channel->name);
+
+ cds_list_for_each_entry(stream, &channel->stream_list.head, list) {
+ DBG("Flushing channel stream %d", stream->fd);
+ ret = kernctl_buffer_flush(stream->fd);
+ if (ret < 0) {
+ perror("ioctl");
+ ERR("Fail to flush buffer for stream %d (ret: %d)",
+ stream->fd, ret);
+ }
+ }
+
+ return 0;
+}
+
+/*
+ * Stop tracing session.
+ */
+int kernel_stop_session(struct ltt_kernel_session *session)
+{
+ int ret;
+
+ ret = kernctl_stop_session(session->fd);
+ if (ret < 0) {
+ goto error;
+ }
+
+ DBG("Kernel session stopped");
+
+ return 0;
+
+error:
+ return ret;
+}
+
+/*
+ * Open stream of channel, register it to the kernel tracer and add it
+ * to the stream list of the channel.
+ *
+ * Return the number of created stream. Else, a negative value.
+ */
+int kernel_open_channel_stream(struct ltt_kernel_channel *channel)
+{
+ int ret;
+ struct ltt_kernel_stream *lks;
+
+ while ((ret = kernctl_create_stream(channel->fd)) > 0) {
+ lks = trace_kernel_create_stream();
+ if (lks == NULL) {
+ close(ret);
+ goto error;
+ }
+
+ lks->fd = ret;
+ /* Prevent fd duplication after execlp() */
+ ret = fcntl(lks->fd, F_SETFD, FD_CLOEXEC);
+ if (ret < 0) {
+ perror("fcntl session fd");
+ }
+
+ ret = asprintf(&lks->pathname, "%s/%s_%d",
+ channel->pathname, channel->channel->name, channel->stream_count);
+ if (ret < 0) {
+ perror("asprintf kernel create stream");
+ goto error;
+ }
+
+ /* Add stream to channe stream list */
+ cds_list_add(&lks->list, &channel->stream_list.head);
+ channel->stream_count++;
+
+ DBG("Kernel stream %d created (fd: %d, state: %d, path: %s)",
+ channel->stream_count, lks->fd, lks->state, lks->pathname);
+ }
+
+ return channel->stream_count;
+
+error:
+ return -1;
+}
+
+/*
+ * Open the metadata stream and set it to the kernel session.
+ */
+int kernel_open_metadata_stream(struct ltt_kernel_session *session)
+{
+ int ret;
+
+ ret = kernctl_create_stream(session->metadata->fd);
+ if (ret < 0) {
+ perror("kernel create metadata stream");
+ goto error;
+ }
+
+ DBG("Kernel metadata stream created (fd: %d)", ret);
+ session->metadata_stream_fd = ret;
+ /* Prevent fd duplication after execlp() */
+ ret = fcntl(session->metadata_stream_fd, F_SETFD, FD_CLOEXEC);
+ if (ret < 0) {
+ perror("fcntl session fd");
+ }
+
+ return 0;
+
+error:
+ return -1;
+}
+
+/*
+ * Get the event list from the kernel tracer and return the number of elements.
+ */
+ssize_t kernel_list_events(int tracer_fd, struct lttng_event **events)
+{
+ int fd, pos;
+ char *event;
+ size_t nbmem, count = 0;
+ ssize_t size;
+ FILE *fp;
+ struct lttng_event *elist;
+
+ fd = kernctl_tracepoint_list(tracer_fd);
+ if (fd < 0) {
+ perror("kernel tracepoint list");
+ goto error;
+ }
+
+ fp = fdopen(fd, "r");
+ if (fp == NULL) {
+ perror("kernel tracepoint list fdopen");
+ goto error_fp;
+ }
+
+ /*
+ * Init memory size counter
+ * See kernel-ctl.h for explanation of this value
+ */
+ nbmem = KERNEL_EVENT_LIST_SIZE;
+ elist = zmalloc(sizeof(struct lttng_event) * nbmem);
+
+ while ((size = fscanf(fp, "event { name = %m[^;]; };%n\n", &event, &pos)) == 1) {
+ if (count > nbmem) {
+ DBG("Reallocating event list from %zu to %zu bytes", nbmem,
+ nbmem + KERNEL_EVENT_LIST_SIZE);
+ /* Adding the default size again */
+ nbmem += KERNEL_EVENT_LIST_SIZE;
+ elist = realloc(elist, nbmem);
+ if (elist == NULL) {
+ perror("realloc list events");
+ count = -ENOMEM;
+ goto end;
+ }
+ }
+ strncpy(elist[count].name, event, LTTNG_SYMBOL_NAME_LEN);
+ elist[count].name[LTTNG_SYMBOL_NAME_LEN - 1] = '\0';
+ count++;
+ }
+
+ *events = elist;
+ DBG("Kernel list events done (%zu events)", count);
+end:
+ fclose(fp); /* closes both fp and fd */
+ return count;
+
+error_fp:
+ close(fd);
+error:
+ return -1;
+}
projects / lttng-tools.git / blobdiff