/*
* 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 free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License, version 2 only,
+ * as published by the Free Software Foundation.
*
* 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.
+ * 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.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*/
-#define _GNU_SOURCE
+#define _LGPL_SOURCE
#include <errno.h>
#include <fcntl.h>
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <unistd.h>
+#include <inttypes.h>
#include <common/common.h>
#include <common/kernel-ctl/kernel-ctl.h>
+#include <common/kernel-ctl/kernel-ioctl.h>
+#include <common/sessiond-comm/sessiond-comm.h>
+#include "consumer.h"
#include "kernel.h"
+#include "kernel-consumer.h"
#include "kern-modules.h"
+#include "utils.h"
/*
* Add context on a kernel channel.
*/
int kernel_add_channel_context(struct ltt_kernel_channel *chan,
- struct lttng_kernel_context *ctx)
+ struct ltt_kernel_context *ctx)
{
int ret;
+ assert(chan);
+ assert(ctx);
+
DBG("Adding context to channel %s", chan->channel->name);
- ret = kernctl_add_context(chan->fd, ctx);
+ ret = kernctl_add_context(chan->fd, &ctx->ctx);
if (ret < 0) {
- if (errno != EEXIST) {
- perror("add context ioctl");
- } else {
+ switch (errno) {
+ case ENOSYS:
+ /* Exists but not available for this kernel */
+ ret = LTTNG_ERR_KERN_CONTEXT_UNAVAILABLE;
+ goto error;
+ case EEXIST:
/* If EEXIST, we just ignore the error */
ret = 0;
+ goto end;
+ default:
+ PERROR("add context ioctl");
+ ret = LTTNG_ERR_KERN_CONTEXT_FAIL;
+ goto error;
}
- 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));
-
+end:
+ cds_list_add_tail(&ctx->list, &chan->ctx_list);
return 0;
error:
int ret;
struct ltt_kernel_session *lks;
+ assert(session);
+
/* Allocate data structure */
- lks = trace_kernel_create_session(session->path);
+ lks = trace_kernel_create_session();
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");
+ PERROR("ioctl kernel create session");
goto error;
}
/* Prevent fd duplication after execlp() */
ret = fcntl(lks->fd, F_SETFD, FD_CLOEXEC);
if (ret < 0) {
- perror("fcntl session fd");
+ PERROR("fcntl session fd");
}
+ lks->id = session->id;
lks->consumer_fds_sent = 0;
session->kernel_session = lks;
return 0;
error:
+ if (lks) {
+ trace_kernel_destroy_session(lks);
+ }
return ret;
}
* kernel session.
*/
int kernel_create_channel(struct ltt_kernel_session *session,
- struct lttng_channel *chan, char *path)
+ struct lttng_channel *chan)
{
int ret;
struct ltt_kernel_channel *lkc;
+ assert(session);
+ assert(chan);
+
/* Allocate kernel channel */
- lkc = trace_kernel_create_channel(chan, path);
+ lkc = trace_kernel_create_channel(chan);
if (lkc == NULL) {
goto error;
}
+ DBG3("Kernel create channel %s with attr: %d, %" PRIu64 ", %" PRIu64 ", %u, %u, %d, %d",
+ chan->name, lkc->channel->attr.overwrite,
+ lkc->channel->attr.subbuf_size, lkc->channel->attr.num_subbuf,
+ lkc->channel->attr.switch_timer_interval, lkc->channel->attr.read_timer_interval,
+ lkc->channel->attr.live_timer_interval, lkc->channel->attr.output);
+
/* Kernel tracer channel creation */
ret = kernctl_create_channel(session->fd, &lkc->channel->attr);
if (ret < 0) {
- perror("ioctl kernel create channel");
+ PERROR("ioctl kernel create channel");
goto error;
}
/* Prevent fd duplication after execlp() */
ret = fcntl(lkc->fd, F_SETFD, FD_CLOEXEC);
if (ret < 0) {
- perror("fcntl session fd");
+ PERROR("fcntl session fd");
}
/* Add channel to session */
cds_list_add(&lkc->list, &session->channel_list.head);
session->channel_count++;
+ lkc->session = session;
- DBG("Kernel channel %s created (fd: %d and path: %s)",
- lkc->channel->name, lkc->fd, lkc->pathname);
+ DBG("Kernel channel %s created (fd: %d)", lkc->channel->name, lkc->fd);
return 0;
error:
+ if (lkc) {
+ free(lkc->channel);
+ free(lkc);
+ }
return -1;
}
/*
* Create a kernel event, enable it to the kernel tracer and add it to the
* channel event list of the kernel session.
+ * We own filter_expression and filter.
*/
int kernel_create_event(struct lttng_event *ev,
- struct ltt_kernel_channel *channel)
+ struct ltt_kernel_channel *channel,
+ char *filter_expression,
+ struct lttng_filter_bytecode *filter)
{
int ret;
struct ltt_kernel_event *event;
- event = trace_kernel_create_event(ev);
+ assert(ev);
+ assert(channel);
+
+ /* We pass ownership of filter_expression and filter */
+ event = trace_kernel_create_event(ev, filter_expression,
+ filter);
if (event == NULL) {
ret = -1;
goto error;
ret = kernctl_create_event(channel->fd, event->event);
if (ret < 0) {
- if (errno != EEXIST) {
+ switch (errno) {
+ case EEXIST:
+ break;
+ case ENOSYS:
+ WARN("Event type not implemented");
+ break;
+ case ENOENT:
+ WARN("Event %s not found!", ev->name);
+ break;
+ default:
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->type = ev->type;
event->fd = ret;
/* Prevent fd duplication after execlp() */
ret = fcntl(event->fd, F_SETFD, FD_CLOEXEC);
if (ret < 0) {
- perror("fcntl session fd");
+ PERROR("fcntl session fd");
+ }
+
+ if (filter) {
+ ret = kernctl_filter(event->fd, filter);
+ if (ret) {
+ goto filter_error;
+ }
+ }
+
+ ret = kernctl_enable(event->fd);
+ if (ret < 0) {
+ switch (errno) {
+ case EEXIST:
+ ret = LTTNG_ERR_KERN_EVENT_EXIST;
+ break;
+ default:
+ PERROR("enable kernel event");
+ break;
+ }
+ goto enable_error;
}
/* Add event to event list */
DBG("Event %s created (fd: %d)", ev->name, event->fd);
-end:
return 0;
+enable_error:
+filter_error:
+ {
+ int closeret;
+
+ closeret = close(event->fd);
+ if (closeret) {
+ PERROR("close event fd");
+ }
+ }
free_event:
free(event);
error:
{
int ret;
+ assert(chan);
+
ret = kernctl_disable(chan->fd);
if (ret < 0) {
- perror("disable chan ioctl");
+ PERROR("disable chan ioctl");
ret = errno;
goto error;
}
{
int ret;
+ assert(chan);
+
ret = kernctl_enable(chan->fd);
if (ret < 0 && errno != EEXIST) {
- perror("Enable kernel chan");
+ PERROR("Enable kernel chan");
goto error;
}
{
int ret;
+ assert(event);
+
ret = kernctl_enable(event->fd);
- if (ret < 0 && errno != EEXIST) {
- perror("enable kernel event");
+ if (ret < 0) {
+ switch (errno) {
+ case EEXIST:
+ ret = LTTNG_ERR_KERN_EVENT_EXIST;
+ break;
+ default:
+ PERROR("enable kernel event");
+ break;
+ }
goto error;
}
{
int ret;
+ assert(event);
+
ret = kernctl_disable(event->fd);
- if (ret < 0 && errno != EEXIST) {
- perror("disable kernel event");
+ if (ret < 0) {
+ switch (errno) {
+ case EEXIST:
+ ret = LTTNG_ERR_KERN_EVENT_EXIST;
+ break;
+ default:
+ PERROR("disable kernel event");
+ break;
+ }
goto error;
}
return ret;
}
+
+int kernel_track_pid(struct ltt_kernel_session *session, int pid)
+{
+ int ret;
+
+ DBG("Kernel track PID %d for session id %" PRIu64 ".",
+ pid, session->id);
+ ret = kernctl_track_pid(session->fd, pid);
+ if (!ret) {
+ return LTTNG_OK;
+ }
+ switch (errno) {
+ case EINVAL:
+ return LTTNG_ERR_INVALID;
+ case ENOMEM:
+ return LTTNG_ERR_NOMEM;
+ case EEXIST:
+ return LTTNG_ERR_PID_TRACKED;
+ default:
+ return LTTNG_ERR_UNK;
+ }
+}
+
+int kernel_untrack_pid(struct ltt_kernel_session *session, int pid)
+{
+ int ret;
+
+ DBG("Kernel untrack PID %d for session id %" PRIu64 ".",
+ pid, session->id);
+ ret = kernctl_untrack_pid(session->fd, pid);
+ if (!ret) {
+ return LTTNG_OK;
+ }
+ switch (errno) {
+ case EINVAL:
+ return LTTNG_ERR_INVALID;
+ case ENOMEM:
+ return LTTNG_ERR_NOMEM;
+ case ENOENT:
+ return LTTNG_ERR_PID_NOT_TRACKED;
+ default:
+ return LTTNG_ERR_UNK;
+ }
+}
+
+ssize_t kernel_list_tracker_pids(struct ltt_kernel_session *session,
+ int **_pids)
+{
+ int fd, ret;
+ int pid;
+ ssize_t nbmem, count = 0;
+ FILE *fp;
+ int *pids;
+
+ fd = kernctl_list_tracker_pids(session->fd);
+ if (fd < 0) {
+ PERROR("kernel tracker pids list");
+ goto error;
+ }
+
+ fp = fdopen(fd, "r");
+ if (fp == NULL) {
+ PERROR("kernel tracker pids list fdopen");
+ goto error_fp;
+ }
+
+ nbmem = KERNEL_TRACKER_PIDS_INIT_LIST_SIZE;
+ pids = zmalloc(sizeof(*pids) * nbmem);
+ if (pids == NULL) {
+ PERROR("alloc list pids");
+ count = -ENOMEM;
+ goto end;
+ }
+
+ while (fscanf(fp, "process { pid = %u; };\n", &pid) == 1) {
+ if (count >= nbmem) {
+ int *new_pids;
+ size_t new_nbmem;
+
+ new_nbmem = nbmem << 1;
+ DBG("Reallocating pids list from %zu to %zu entries",
+ nbmem, new_nbmem);
+ new_pids = realloc(pids, new_nbmem * sizeof(*new_pids));
+ if (new_pids == NULL) {
+ PERROR("realloc list events");
+ free(pids);
+ count = -ENOMEM;
+ goto end;
+ }
+ /* Zero the new memory */
+ memset(new_pids + nbmem, 0,
+ (new_nbmem - nbmem) * sizeof(*new_pids));
+ nbmem = new_nbmem;
+ pids = new_pids;
+ }
+ pids[count++] = pid;
+ }
+
+ *_pids = pids;
+ DBG("Kernel list tracker pids done (%zd pids)", count);
+end:
+ ret = fclose(fp); /* closes both fp and fd */
+ if (ret) {
+ PERROR("fclose");
+ }
+ return count;
+
+error_fp:
+ ret = close(fd);
+ if (ret) {
+ PERROR("close");
+ }
+error:
+ return -1;
+}
+
/*
* 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 kernel_open_metadata(struct ltt_kernel_session *session)
{
int ret;
- struct ltt_kernel_metadata *lkm;
+ struct ltt_kernel_metadata *lkm = NULL;
+
+ assert(session);
/* Allocate kernel metadata */
- lkm = trace_kernel_create_metadata(path);
+ lkm = trace_kernel_create_metadata();
if (lkm == NULL) {
goto error;
}
/* Kernel tracer metadata creation */
ret = kernctl_open_metadata(session->fd, &lkm->conf->attr);
if (ret < 0) {
- goto error;
+ goto error_open;
}
lkm->fd = ret;
/* Prevent fd duplication after execlp() */
ret = fcntl(lkm->fd, F_SETFD, FD_CLOEXEC);
if (ret < 0) {
- perror("fcntl session fd");
+ PERROR("fcntl session fd");
}
session->metadata = lkm;
- DBG("Kernel metadata opened (fd: %d and path: %s)", lkm->fd, lkm->pathname);
+ DBG("Kernel metadata opened (fd: %d)", lkm->fd);
return 0;
+error_open:
+ trace_kernel_destroy_metadata(lkm);
error:
return -1;
}
{
int ret;
+ assert(session);
+
ret = kernctl_start_session(session->fd);
if (ret < 0) {
- perror("ioctl start session");
+ PERROR("ioctl start session");
goto error;
}
ret = kernctl_wait_quiescent(fd);
if (ret < 0) {
- perror("wait quiescent ioctl");
+ PERROR("wait quiescent ioctl");
ERR("Kernel quiescent wait failed");
}
}
{
int ret;
+ assert(calibrate);
+
ret = kernctl_calibrate(fd, calibrate);
if (ret < 0) {
- perror("calibrate ioctl");
+ PERROR("calibrate ioctl");
return -1;
}
{
int ret;
+ DBG("Kernel flushing metadata buffer on fd %d", fd);
+
ret = kernctl_buffer_flush(fd);
if (ret < 0) {
- ERR("Fail to flush metadata buffers %d (ret: %d", fd, ret);
+ ERR("Fail to flush metadata buffers %d (ret: %d)", fd, ret);
}
return 0;
int ret;
struct ltt_kernel_stream *stream;
+ assert(channel);
+
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");
+ PERROR("ioctl");
ERR("Fail to flush buffer for stream %d (ret: %d)",
stream->fd, ret);
}
{
int ret;
+ assert(session);
+
ret = kernctl_stop_session(session->fd);
if (ret < 0) {
goto error;
*/
int kernel_open_channel_stream(struct ltt_kernel_channel *channel)
{
- int ret;
+ int ret, count = 0;
struct ltt_kernel_stream *lks;
- while ((ret = kernctl_create_stream(channel->fd)) > 0) {
- lks = trace_kernel_create_stream();
+ assert(channel);
+
+ while ((ret = kernctl_create_stream(channel->fd)) >= 0) {
+ lks = trace_kernel_create_stream(channel->channel->name, count);
if (lks == NULL) {
- close(ret);
+ ret = close(ret);
+ if (ret) {
+ PERROR("close");
+ }
goto error;
}
/* Prevent fd duplication after execlp() */
ret = fcntl(lks->fd, F_SETFD, FD_CLOEXEC);
if (ret < 0) {
- perror("fcntl session fd");
+ 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;
- }
+ lks->tracefile_size = channel->channel->attr.tracefile_size;
+ lks->tracefile_count = channel->channel->attr.tracefile_count;
/* 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);
+ /* Increment counter which represent CPU number. */
+ count++;
+
+ DBG("Kernel stream %s created (fd: %d, state: %d)", lks->name, lks->fd,
+ lks->state);
}
return channel->stream_count;
{
int ret;
+ assert(session);
+
ret = kernctl_create_stream(session->metadata->fd);
if (ret < 0) {
- perror("kernel create metadata stream");
+ PERROR("kernel create metadata stream");
goto error;
}
/* Prevent fd duplication after execlp() */
ret = fcntl(session->metadata_stream_fd, F_SETFD, FD_CLOEXEC);
if (ret < 0) {
- perror("fcntl session fd");
+ PERROR("fcntl session fd");
}
return 0;
*/
ssize_t kernel_list_events(int tracer_fd, struct lttng_event **events)
{
- int fd, pos;
+ int fd, ret;
char *event;
size_t nbmem, count = 0;
- ssize_t size;
FILE *fp;
struct lttng_event *elist;
+ assert(events);
+
fd = kernctl_tracepoint_list(tracer_fd);
if (fd < 0) {
- perror("kernel tracepoint list");
+ PERROR("kernel tracepoint list");
goto error;
}
fp = fdopen(fd, "r");
if (fp == NULL) {
- perror("kernel tracepoint list fdopen");
+ PERROR("kernel tracepoint list fdopen");
goto error_fp;
}
*/
nbmem = KERNEL_EVENT_INIT_LIST_SIZE;
elist = zmalloc(sizeof(struct lttng_event) * nbmem);
+ if (elist == NULL) {
+ PERROR("alloc list events");
+ count = -ENOMEM;
+ goto end;
+ }
- while ((size = fscanf(fp, "event { name = %m[^;]; };%n\n", &event, &pos)) == 1) {
+ while (fscanf(fp, "event { name = %m[^;]; };\n", &event) == 1) {
if (count >= nbmem) {
- DBG("Reallocating event list from %zu to %zu bytes", nbmem,
- nbmem * 2);
- /* Double the size */
- nbmem <<= 1;
- elist = realloc(elist, nbmem * sizeof(struct lttng_event));
- if (elist == NULL) {
- perror("realloc list events");
+ struct lttng_event *new_elist;
+ size_t new_nbmem;
+
+ new_nbmem = nbmem << 1;
+ DBG("Reallocating event list from %zu to %zu bytes",
+ nbmem, new_nbmem);
+ new_elist = realloc(elist, new_nbmem * sizeof(struct lttng_event));
+ if (new_elist == NULL) {
+ PERROR("realloc list events");
+ free(event);
+ free(elist);
count = -ENOMEM;
goto end;
}
+ /* Zero the new memory */
+ memset(new_elist + nbmem, 0,
+ (new_nbmem - nbmem) * sizeof(struct lttng_event));
+ nbmem = new_nbmem;
+ elist = new_elist;
}
strncpy(elist[count].name, event, LTTNG_SYMBOL_NAME_LEN);
elist[count].name[LTTNG_SYMBOL_NAME_LEN - 1] = '\0';
elist[count].enabled = -1;
count++;
+ free(event);
}
*events = elist;
DBG("Kernel list events done (%zu events)", count);
end:
- fclose(fp); /* closes both fp and fd */
+ ret = fclose(fp); /* closes both fp and fd */
+ if (ret) {
+ PERROR("fclose");
+ }
return count;
error_fp:
- close(fd);
+ ret = close(fd);
+ if (ret) {
+ PERROR("close");
+ }
error:
return -1;
}
{
int ret;
struct lttng_kernel_tracer_version version;
+ struct lttng_kernel_tracer_abi_version abi_version;
ret = kernctl_tracer_version(tracer_fd, &version);
if (ret < 0) {
- ERR("Failed at getting the lttng-modules version");
+ ERR("Failed to retrieve the lttng-modules version");
goto error;
}
/* Validate version */
- if (version.version != KERN_MODULES_PRE_VERSION
- && version.version != KERN_MODULES_VERSION) {
+ if (version.major != VERSION_MAJOR) {
+ ERR("Kernel tracer major version (%d) is not compatible with lttng-tools major version (%d)",
+ version.major, VERSION_MAJOR);
goto error_version;
}
-
- DBG2("Kernel tracer version validated (major version %d)", version.version);
+ ret = kernctl_tracer_abi_version(tracer_fd, &abi_version);
+ if (ret < 0) {
+ ERR("Failed to retrieve lttng-modules ABI version");
+ goto error;
+ }
+ if (abi_version.major != LTTNG_MODULES_ABI_MAJOR_VERSION) {
+ ERR("Kernel tracer ABI version (%d.%d) does not match the expected ABI major version (%d.*)",
+ abi_version.major, abi_version.minor,
+ LTTNG_MODULES_ABI_MAJOR_VERSION);
+ goto error;
+ }
+ DBG2("Kernel tracer version validated (%d.%d, ABI %d.%d)",
+ version.major, version.minor,
+ abi_version.major, abi_version.minor);
return 0;
error_version:
- ERR("Kernel major version %d is not compatible (supporting <= %d)",
- version.version, KERN_MODULES_VERSION)
ret = -1;
error:
+ ERR("Kernel tracer version check failed; kernel tracing will not be available");
return ret;
}
/* Ignore error, we don't really care */
}
}
- fclose(fp);
+ ret = fclose(fp);
+ if (ret) {
+ PERROR("fclose");
+ }
end_boot_id:
-
return 0;
}
+
+/*
+ * Complete teardown of a kernel session.
+ */
+void kernel_destroy_session(struct ltt_kernel_session *ksess)
+{
+ if (ksess == NULL) {
+ DBG3("No kernel session when tearing down session");
+ return;
+ }
+
+ DBG("Tearing down kernel session");
+
+ /*
+ * Destroy channels on the consumer if at least one FD has been sent and we
+ * are in no output mode because the streams are in *no* monitor mode so we
+ * have to send a command to clean them up or else they leaked.
+ */
+ if (!ksess->output_traces && ksess->consumer_fds_sent) {
+ int ret;
+ struct consumer_socket *socket;
+ struct lttng_ht_iter iter;
+
+ /* For each consumer socket. */
+ rcu_read_lock();
+ cds_lfht_for_each_entry(ksess->consumer->socks->ht, &iter.iter,
+ socket, node.node) {
+ struct ltt_kernel_channel *chan;
+
+ /* For each channel, ask the consumer to destroy it. */
+ cds_list_for_each_entry(chan, &ksess->channel_list.head, list) {
+ ret = kernel_consumer_destroy_channel(socket, chan);
+ if (ret < 0) {
+ /* Consumer is probably dead. Use next socket. */
+ continue;
+ }
+ }
+ }
+ rcu_read_unlock();
+ }
+
+ /* Close any relayd session */
+ consumer_output_send_destroy_relayd(ksess->consumer);
+
+ trace_kernel_destroy_session(ksess);
+}
+
+/*
+ * Destroy a kernel channel object. It does not do anything on the tracer side.
+ */
+void kernel_destroy_channel(struct ltt_kernel_channel *kchan)
+{
+ struct ltt_kernel_session *ksess = NULL;
+
+ assert(kchan);
+ assert(kchan->channel);
+
+ DBG3("Kernel destroy channel %s", kchan->channel->name);
+
+ /* Update channel count of associated session. */
+ if (kchan->session) {
+ /* Keep pointer reference so we can update it after the destroy. */
+ ksess = kchan->session;
+ }
+
+ trace_kernel_destroy_channel(kchan);
+
+ /*
+ * At this point the kernel channel is not visible anymore. This is safe
+ * since in order to work on a visible kernel session, the tracing session
+ * lock (ltt_session.lock) MUST be acquired.
+ */
+ if (ksess) {
+ ksess->channel_count--;
+ }
+}
+
+/*
+ * Take a snapshot for a given kernel session.
+ *
+ * Return 0 on success or else return a LTTNG_ERR code.
+ */
+int kernel_snapshot_record(struct ltt_kernel_session *ksess,
+ struct snapshot_output *output, int wait,
+ uint64_t nb_packets_per_stream)
+{
+ int err, ret, saved_metadata_fd;
+ struct consumer_socket *socket;
+ struct lttng_ht_iter iter;
+ struct ltt_kernel_metadata *saved_metadata;
+
+ assert(ksess);
+ assert(ksess->consumer);
+ assert(output);
+
+ DBG("Kernel snapshot record started");
+
+ /* Save current metadata since the following calls will change it. */
+ saved_metadata = ksess->metadata;
+ saved_metadata_fd = ksess->metadata_stream_fd;
+
+ rcu_read_lock();
+
+ ret = kernel_open_metadata(ksess);
+ if (ret < 0) {
+ ret = LTTNG_ERR_KERN_META_FAIL;
+ goto error;
+ }
+
+ ret = kernel_open_metadata_stream(ksess);
+ if (ret < 0) {
+ ret = LTTNG_ERR_KERN_META_FAIL;
+ goto error_open_stream;
+ }
+
+ /* Send metadata to consumer and snapshot everything. */
+ cds_lfht_for_each_entry(ksess->consumer->socks->ht, &iter.iter,
+ socket, node.node) {
+ struct consumer_output *saved_output;
+ struct ltt_kernel_channel *chan;
+
+ /*
+ * Temporarly switch consumer output for our snapshot output. As long
+ * as the session lock is taken, this is safe.
+ */
+ saved_output = ksess->consumer;
+ ksess->consumer = output->consumer;
+
+ pthread_mutex_lock(socket->lock);
+ /* This stream must not be monitored by the consumer. */
+ ret = kernel_consumer_add_metadata(socket, ksess, 0);
+ pthread_mutex_unlock(socket->lock);
+ /* Put back the saved consumer output into the session. */
+ ksess->consumer = saved_output;
+ if (ret < 0) {
+ ret = LTTNG_ERR_KERN_CONSUMER_FAIL;
+ goto error_consumer;
+ }
+
+ /* For each channel, ask the consumer to snapshot it. */
+ cds_list_for_each_entry(chan, &ksess->channel_list.head, list) {
+ pthread_mutex_lock(socket->lock);
+ ret = consumer_snapshot_channel(socket, chan->fd, output, 0,
+ ksess->uid, ksess->gid,
+ DEFAULT_KERNEL_TRACE_DIR, wait,
+ nb_packets_per_stream);
+ pthread_mutex_unlock(socket->lock);
+ if (ret < 0) {
+ ret = LTTNG_ERR_KERN_CONSUMER_FAIL;
+ (void) kernel_consumer_destroy_metadata(socket,
+ ksess->metadata);
+ goto error_consumer;
+ }
+ }
+
+ /* Snapshot metadata, */
+ pthread_mutex_lock(socket->lock);
+ ret = consumer_snapshot_channel(socket, ksess->metadata->fd, output,
+ 1, ksess->uid, ksess->gid,
+ DEFAULT_KERNEL_TRACE_DIR, wait, 0);
+ pthread_mutex_unlock(socket->lock);
+ if (ret < 0) {
+ ret = LTTNG_ERR_KERN_CONSUMER_FAIL;
+ goto error_consumer;
+ }
+
+ /*
+ * The metadata snapshot is done, ask the consumer to destroy it since
+ * it's not monitored on the consumer side.
+ */
+ (void) kernel_consumer_destroy_metadata(socket, ksess->metadata);
+ }
+
+ ret = LTTNG_OK;
+
+error_consumer:
+ /* Close newly opened metadata stream. It's now on the consumer side. */
+ err = close(ksess->metadata_stream_fd);
+ if (err < 0) {
+ PERROR("close snapshot kernel");
+ }
+
+error_open_stream:
+ trace_kernel_destroy_metadata(ksess->metadata);
+error:
+ /* Restore metadata state.*/
+ ksess->metadata = saved_metadata;
+ ksess->metadata_stream_fd = saved_metadata_fd;
+
+ rcu_read_unlock();
+ return ret;
+}
+
+/*
+ * Get the syscall mask array from the kernel tracer.
+ *
+ * Return 0 on success else a negative value. In both case, syscall_mask should
+ * be freed.
+ */
+int kernel_syscall_mask(int chan_fd, char **syscall_mask, uint32_t *nr_bits)
+{
+ assert(syscall_mask);
+ assert(nr_bits);
+
+ return kernctl_syscall_mask(chan_fd, syscall_mask, nr_bits);
+}
projects / lttng-tools.git / blobdiff