* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*/
-#define _GNU_SOURCE
-#include <errno.h>
+#define _LGPL_SOURCE
#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"
+#include "rotate.h"
+/*
+ * Key used to reference a channel between the sessiond and the consumer. This
+ * is only read and updated with the session_list lock held.
+ */
+static uint64_t next_kernel_channel_key;
+
+#include <lttng/userspace-probe.h>
+#include <lttng/userspace-probe-internal.h>
/*
* Add context on a kernel channel.
+ *
+ * Assumes the ownership of ctx.
*/
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 (-ret) {
+ 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;
}
+ ret = 0;
- memcpy(chan->ctx, ctx, sizeof(struct lttng_kernel_context));
-
- return 0;
-
+end:
+ cds_list_add_tail(&ctx->list, &chan->ctx_list);
+ ctx->in_list = true;
+ ctx = NULL;
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;
+ if (ctx) {
+ trace_kernel_destroy_context(ctx);
}
-
- 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;
}
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;
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 in %s with attr: %d, %zu, %zu, %u, %u, %d",
- chan->name, path, lkc->channel->attr.overwrite,
+ 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.output);
+ lkc->channel->attr.live_timer_interval, lkc->channel->attr.output);
/* Kernel tracer channel creation */
ret = kernctl_create_channel(session->fd, &lkc->channel->attr);
/* Add channel to session */
cds_list_add(&lkc->list, &session->channel_list.head);
session->channel_count++;
+ lkc->session = session;
+ lkc->key = ++next_kernel_channel_key;
- DBG("Kernel channel %s created (fd: %d)", lkc->channel->name, lkc->fd);
+ DBG("Kernel channel %s created (fd: %d, key: %" PRIu64 ")",
+ lkc->channel->name, lkc->fd, lkc->key);
return 0;
error:
+ if (lkc) {
+ free(lkc->channel);
+ free(lkc);
+ }
return -1;
}
+/*
+ * Compute the offset of the instrumentation byte in the binary based on the
+ * function probe location using the ELF lookup method.
+ *
+ * Returns 0 on success and set the offset out parameter to the offset of the
+ * elf symbol
+ * Returns -1 on error
+ */
+static
+int extract_userspace_probe_offset_function_elf(
+ const struct lttng_userspace_probe_location *probe_location,
+ struct ltt_kernel_session *session, uint64_t *offset)
+{
+ int fd;
+ int ret = 0;
+ const char *symbol = NULL;
+ const struct lttng_userspace_probe_location_lookup_method *lookup = NULL;
+ enum lttng_userspace_probe_location_lookup_method_type lookup_method_type;
+
+ assert(lttng_userspace_probe_location_get_type(probe_location) ==
+ LTTNG_USERSPACE_PROBE_LOCATION_TYPE_FUNCTION);
+
+ lookup = lttng_userspace_probe_location_get_lookup_method(
+ probe_location);
+ if (!lookup) {
+ ret = -1;
+ goto end;
+ }
+
+ lookup_method_type =
+ lttng_userspace_probe_location_lookup_method_get_type(lookup);
+
+ assert(lookup_method_type ==
+ LTTNG_USERSPACE_PROBE_LOCATION_LOOKUP_METHOD_TYPE_FUNCTION_ELF);
+
+ symbol = lttng_userspace_probe_location_function_get_function_name(
+ probe_location);
+ if (!symbol) {
+ ret = -1;
+ goto end;
+ }
+
+ fd = lttng_userspace_probe_location_function_get_binary_fd(probe_location);
+ if (fd < 0) {
+ ret = -1;
+ goto end;
+ }
+
+ ret = run_as_extract_elf_symbol_offset(fd, symbol, session->uid,
+ session->gid, offset);
+ if (ret < 0) {
+ DBG("userspace probe offset calculation failed for "
+ "function %s", symbol);
+ goto end;
+ }
+
+ DBG("userspace probe elf offset for %s is 0x%jd", symbol, (intmax_t)(*offset));
+end:
+ return ret;
+}
+
+/*
+ * Compute the offsets of the instrumentation bytes in the binary based on the
+ * tracepoint probe location using the SDT lookup method. This function
+ * allocates the offsets buffer, the caller must free it.
+ *
+ * Returns 0 on success and set the offset out parameter to the offsets of the
+ * SDT tracepoint.
+ * Returns -1 on error.
+ */
+static
+int extract_userspace_probe_offset_tracepoint_sdt(
+ const struct lttng_userspace_probe_location *probe_location,
+ struct ltt_kernel_session *session, uint64_t **offsets,
+ uint32_t *offsets_count)
+{
+ enum lttng_userspace_probe_location_lookup_method_type lookup_method_type;
+ const struct lttng_userspace_probe_location_lookup_method *lookup = NULL;
+ const char *probe_name = NULL, *provider_name = NULL;
+ int ret = 0;
+ int fd, i;
+
+ assert(lttng_userspace_probe_location_get_type(probe_location) ==
+ LTTNG_USERSPACE_PROBE_LOCATION_TYPE_TRACEPOINT);
+
+ lookup = lttng_userspace_probe_location_get_lookup_method(probe_location);
+ if (!lookup) {
+ ret = -1;
+ goto end;
+ }
+
+ lookup_method_type =
+ lttng_userspace_probe_location_lookup_method_get_type(lookup);
+
+ assert(lookup_method_type ==
+ LTTNG_USERSPACE_PROBE_LOCATION_LOOKUP_METHOD_TYPE_TRACEPOINT_SDT);
+
+
+ probe_name = lttng_userspace_probe_location_tracepoint_get_probe_name(
+ probe_location);
+ if (!probe_name) {
+ ret = -1;
+ goto end;
+ }
+
+ provider_name = lttng_userspace_probe_location_tracepoint_get_provider_name(
+ probe_location);
+ if (!provider_name) {
+ ret = -1;
+ goto end;
+ }
+
+ fd = lttng_userspace_probe_location_tracepoint_get_binary_fd(probe_location);
+ if (fd < 0) {
+ ret = -1;
+ goto end;
+ }
+
+ ret = run_as_extract_sdt_probe_offsets(fd, provider_name, probe_name,
+ session->uid, session->gid, offsets, offsets_count);
+ if (ret < 0) {
+ DBG("userspace probe offset calculation failed for sdt "
+ "probe %s:%s", provider_name, probe_name);
+ goto end;
+ }
+
+ if (*offsets_count == 0) {
+ DBG("no userspace probe offset found");
+ goto end;
+ }
+
+ DBG("%u userspace probe SDT offsets found for %s:%s at:",
+ *offsets_count, provider_name, probe_name);
+ for (i = 0; i < *offsets_count; i++) {
+ DBG("\t0x%jd", (intmax_t)((*offsets)[i]));
+ }
+end:
+ return ret;
+}
+
+/*
+ * Extract the offsets of the instrumentation point for the different lookup
+ * methods.
+ */
+static
+int userspace_probe_add_callsites(struct lttng_event *ev,
+ struct ltt_kernel_session *session, int fd)
+{
+ const struct lttng_userspace_probe_location_lookup_method *lookup_method = NULL;
+ enum lttng_userspace_probe_location_lookup_method_type type;
+ const struct lttng_userspace_probe_location *location = NULL;
+ int ret;
+
+ assert(ev);
+ assert(ev->type == LTTNG_EVENT_USERSPACE_PROBE);
+
+ location = lttng_event_get_userspace_probe_location(ev);
+ if (!location) {
+ ret = -1;
+ goto end;
+ }
+ lookup_method =
+ lttng_userspace_probe_location_get_lookup_method(location);
+ if (!lookup_method) {
+ ret = -1;
+ goto end;
+ }
+
+ type = lttng_userspace_probe_location_lookup_method_get_type(lookup_method);
+ switch (type) {
+ case LTTNG_USERSPACE_PROBE_LOCATION_LOOKUP_METHOD_TYPE_FUNCTION_ELF:
+ {
+ struct lttng_kernel_event_callsite callsite;
+ uint64_t offset;
+
+ ret = extract_userspace_probe_offset_function_elf(location, session, &offset);
+ if (ret) {
+ ret = LTTNG_ERR_PROBE_LOCATION_INVAL;
+ goto end;
+ }
+
+ callsite.u.uprobe.offset = offset;
+ ret = kernctl_add_callsite(fd, &callsite);
+ if (ret) {
+ WARN("Adding callsite to userspace probe "
+ "event %s failed.", ev->name);
+ ret = LTTNG_ERR_KERN_ENABLE_FAIL;
+ goto end;
+ }
+ break;
+ }
+ case LTTNG_USERSPACE_PROBE_LOCATION_LOOKUP_METHOD_TYPE_TRACEPOINT_SDT:
+ {
+ int i;
+ uint64_t *offsets = NULL;
+ uint32_t offsets_count;
+ struct lttng_kernel_event_callsite callsite;
+
+ /*
+ * This call allocates the offsets buffer. This buffer must be freed
+ * by the caller
+ */
+ ret = extract_userspace_probe_offset_tracepoint_sdt(location, session,
+ &offsets, &offsets_count);
+ if (ret) {
+ ret = LTTNG_ERR_PROBE_LOCATION_INVAL;
+ goto end;
+ }
+ for (i = 0; i < offsets_count; i++) {
+ callsite.u.uprobe.offset = offsets[i];
+ ret = kernctl_add_callsite(fd, &callsite);
+ if (ret) {
+ WARN("Adding callsite to userspace probe "
+ "event %s failed.", ev->name);
+ ret = LTTNG_ERR_KERN_ENABLE_FAIL;
+ free(offsets);
+ goto end;
+ }
+ }
+ free(offsets);
+ break;
+ }
+ default:
+ ret = LTTNG_ERR_PROBE_LOCATION_INVAL;
+ goto end;
+ }
+end:
+ return ret;
+}
+
/*
* 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;
+ int err, fd;
+ enum lttng_error_code ret;
struct ltt_kernel_event *event;
- event = trace_kernel_create_event(ev);
- if (event == NULL) {
- ret = -1;
+ assert(ev);
+ assert(channel);
+
+ /* We pass ownership of filter_expression and filter */
+ ret = trace_kernel_create_event(ev, filter_expression,
+ filter, &event);
+ if (ret != LTTNG_OK) {
goto error;
}
- ret = kernctl_create_event(channel->fd, event->event);
- if (ret < 0) {
- switch (errno) {
+ fd = kernctl_create_event(channel->fd, event->event);
+ if (fd < 0) {
+ switch (-fd) {
case EEXIST:
+ ret = LTTNG_ERR_KERN_EVENT_EXIST;
break;
case ENOSYS:
WARN("Event type not implemented");
+ ret = LTTNG_ERR_KERN_EVENT_ENOSYS;
+ break;
+ case ENOENT:
+ WARN("Event %s not found!", ev->name);
+ ret = LTTNG_ERR_KERN_ENABLE_FAIL;
break;
default:
+ ret = LTTNG_ERR_KERN_ENABLE_FAIL;
PERROR("create event ioctl");
}
- ret = -errno;
goto free_event;
}
- /*
- * LTTNG_KERNEL_SYSCALL event creation will return 0 on success.
- */
- if (ret == 0 && event->event->instrumentation == LTTNG_KERNEL_SYSCALL) {
- DBG2("Kernel event syscall creation success");
- /*
- * We use fd == -1 to ensure that we never trigger a close of fd
- * 0.
- */
- event->fd = -1;
- goto add_list;
- }
-
- event->fd = ret;
+ event->type = ev->type;
+ event->fd = fd;
/* Prevent fd duplication after execlp() */
- ret = fcntl(event->fd, F_SETFD, FD_CLOEXEC);
- if (ret < 0) {
+ err = fcntl(event->fd, F_SETFD, FD_CLOEXEC);
+ if (err < 0) {
PERROR("fcntl session fd");
}
-add_list:
+ if (filter) {
+ err = kernctl_filter(event->fd, filter);
+ if (err < 0) {
+ switch (-err) {
+ case ENOMEM:
+ ret = LTTNG_ERR_FILTER_NOMEM;
+ break;
+ default:
+ ret = LTTNG_ERR_FILTER_INVAL;
+ break;
+ }
+ goto filter_error;
+ }
+ }
+
+ if (ev->type == LTTNG_EVENT_USERSPACE_PROBE) {
+ ret = userspace_probe_add_callsites(ev, channel->session, event->fd);
+ if (ret) {
+ goto add_callsite_error;
+ }
+ }
+
+ err = kernctl_enable(event->fd);
+ if (err < 0) {
+ switch (-err) {
+ case EEXIST:
+ ret = LTTNG_ERR_KERN_EVENT_EXIST;
+ break;
+ default:
+ PERROR("enable kernel event");
+ ret = LTTNG_ERR_KERN_ENABLE_FAIL;
+ break;
+ }
+ goto enable_error;
+ }
+
/* Add event to event list */
cds_list_add(&event->list, &channel->events_list.head);
channel->event_count++;
return 0;
+add_callsite_error:
+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");
- ret = errno;
goto error;
}
chan->enabled = 0;
- DBG("Kernel channel %s disabled (fd: %d)", chan->channel->name, chan->fd);
+ DBG("Kernel channel %s disabled (fd: %d, key: %" PRIu64 ")",
+ chan->channel->name, chan->fd, chan->key);
return 0;
{
int ret;
+ assert(chan);
+
ret = kernctl_enable(chan->fd);
- if (ret < 0 && errno != EEXIST) {
+ if (ret < 0 && ret != -EEXIST) {
PERROR("Enable kernel chan");
goto error;
}
chan->enabled = 1;
- DBG("Kernel channel %s enabled (fd: %d)", chan->channel->name, chan->fd);
+ DBG("Kernel channel %s enabled (fd: %d, key: %" PRIu64 ")",
+ chan->channel->name, chan->fd, chan->key);
return 0;
{
int ret;
+ assert(event);
+
ret = kernctl_enable(event->fd);
if (ret < 0) {
- switch (errno) {
+ switch (-ret) {
case EEXIST:
- ret = LTTCOMM_KERN_EVENT_EXIST;
+ ret = LTTNG_ERR_KERN_EVENT_EXIST;
break;
default:
PERROR("enable kernel event");
{
int ret;
+ assert(event);
+
ret = kernctl_disable(event->fd);
if (ret < 0) {
- switch (errno) {
+ switch (-ret) {
case EEXIST:
- ret = LTTCOMM_KERN_EVENT_EXIST;
+ ret = LTTNG_ERR_KERN_EVENT_EXIST;
break;
default:
PERROR("disable kernel event");
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 (-ret) {
+ 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 (-ret) {
+ 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)
{
int ret;
- struct ltt_kernel_metadata *lkm;
+ struct ltt_kernel_metadata *lkm = NULL;
+
+ assert(session);
/* Allocate kernel metadata */
lkm = trace_kernel_create_metadata();
/* Kernel tracer metadata creation */
ret = kernctl_open_metadata(session->fd, &lkm->conf->attr);
if (ret < 0) {
- goto error;
+ goto error_open;
}
lkm->fd = ret;
+ lkm->key = ++next_kernel_channel_key;
/* Prevent fd duplication after execlp() */
ret = fcntl(lkm->fd, F_SETFD, FD_CLOEXEC);
if (ret < 0) {
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");
}
}
-/*
- * 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 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);
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) {
{
int ret;
+ assert(session);
+
ret = kernctl_stop_session(session->fd);
if (ret < 0) {
goto error;
* Open stream of channel, register it to the kernel tracer and add it
* to the stream list of the channel.
*
+ * Note: given that the streams may appear in random order wrt CPU
+ * number (e.g. cpu hotplug), the index value of the stream number in
+ * the stream name is not necessarily linked to the CPU number.
+ *
* Return the number of created stream. Else, a negative value.
*/
int kernel_open_channel_stream(struct ltt_kernel_channel *channel)
{
- int ret, count = 0;
+ int ret;
struct ltt_kernel_stream *lks;
+ assert(channel);
+
while ((ret = kernctl_create_stream(channel->fd)) >= 0) {
- lks = trace_kernel_create_stream(channel->channel->name, count);
+ lks = trace_kernel_create_stream(channel->channel->name,
+ channel->stream_count);
if (lks == NULL) {
ret = close(ret);
if (ret) {
PERROR("fcntl session fd");
}
- /* Add stream to channe stream list */
+ lks->tracefile_size = channel->channel->attr.tracefile_size;
+ lks->tracefile_count = channel->channel->attr.tracefile_count;
+
+ /* Add stream to channel stream list */
cds_list_add(&lks->list, &channel->stream_list.head);
channel->stream_count++;
- /* Increment counter which represent CPU number. */
- count++;
-
DBG("Kernel stream %s created (fd: %d, state: %d)", lks->name, lks->fd,
lks->state);
}
{
int ret;
+ assert(session);
+
ret = kernctl_create_stream(session->metadata->fd);
if (ret < 0) {
PERROR("kernel create metadata stream");
*/
ssize_t kernel_list_events(int tracer_fd, struct lttng_event **events)
{
- int fd, pos, ret;
+ 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");
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) {
struct lttng_event *new_elist;
+ size_t new_nbmem;
- DBG("Reallocating event list from %zu to %zu bytes", nbmem,
- nbmem * 2);
- /* Double the size */
- nbmem <<= 1;
- new_elist = realloc(elist, nbmem * sizeof(struct lttng_event));
+ 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);
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);
/*
* Get kernel version and validate it.
*/
-int kernel_validate_version(int tracer_fd)
+int kernel_validate_version(int tracer_fd,
+ struct lttng_kernel_tracer_version *version,
+ struct lttng_kernel_tracer_abi_version *abi_version)
{
int ret;
- struct lttng_kernel_tracer_version version;
- ret = kernctl_tracer_version(tracer_fd, &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.major != KERN_MODULES_PRE_MAJOR
- && version.major != KERN_MODULES_MAJOR) {
+ 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.major);
+ 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.major, KERN_MODULES_MAJOR)
ret = -1;
error:
+ ERR("Kernel tracer version check failed; kernel tracing will not be available");
return ret;
}
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;
+ struct ltt_session *session;
+ uint64_t trace_archive_id;
+
+ assert(ksess);
+ assert(ksess->consumer);
+ assert(output);
+
+ DBG("Kernel snapshot record started");
+
+ session = session_find_by_id(ksess->id);
+ assert(session);
+ assert(pthread_mutex_trylock(&session->lock));
+ assert(session_trylock_list());
+ trace_archive_id = session->current_archive_id;
+
+ /* 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) {
+ ret = consumer_snapshot_channel(socket, chan->key, output, 0,
+ ksess->uid, ksess->gid,
+ DEFAULT_KERNEL_TRACE_DIR, wait,
+ nb_packets_per_stream,
+ trace_archive_id);
+ if (ret < 0) {
+ ret = LTTNG_ERR_KERN_CONSUMER_FAIL;
+ (void) kernel_consumer_destroy_metadata(socket,
+ ksess->metadata);
+ goto error_consumer;
+ }
+ }
+
+ /* Snapshot metadata, */
+ ret = consumer_snapshot_channel(socket, ksess->metadata->key, output,
+ 1, ksess->uid, ksess->gid,
+ DEFAULT_KERNEL_TRACE_DIR, wait, 0,
+ trace_archive_id);
+ 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);
+}
+
+/*
+ * Check for the support of the RING_BUFFER_SNAPSHOT_SAMPLE_POSITIONS via abi
+ * version number.
+ *
+ * Return 1 on success, 0 when feature is not supported, negative value in case
+ * of errors.
+ */
+int kernel_supports_ring_buffer_snapshot_sample_positions(int tracer_fd)
+{
+ int ret = 0; // Not supported by default
+ struct lttng_kernel_tracer_abi_version abi;
+
+ ret = kernctl_tracer_abi_version(tracer_fd, &abi);
+ if (ret < 0) {
+ ERR("Failed to retrieve lttng-modules ABI version");
+ goto error;
+ }
+
+ /*
+ * RING_BUFFER_SNAPSHOT_SAMPLE_POSITIONS was introduced in 2.3
+ */
+ if (abi.major >= 2 && abi.minor >= 3) {
+ /* Supported */
+ ret = 1;
+ } else {
+ /* Not supported */
+ ret = 0;
+ }
+error:
+ return ret;
+}
+
+/*
+ * Rotate a kernel session.
+ *
+ * Return LTTNG_OK on success or else an LTTng error code.
+ */
+enum lttng_error_code kernel_rotate_session(struct ltt_session *session)
+{
+ int ret;
+ enum lttng_error_code status = LTTNG_OK;
+ struct consumer_socket *socket;
+ struct lttng_ht_iter iter;
+ struct ltt_kernel_session *ksess = session->kernel_session;
+
+ assert(ksess);
+ assert(ksess->consumer);
+
+ DBG("Rotate kernel session %s started (session %" PRIu64 ")",
+ session->name, session->id);
+
+ rcu_read_lock();
+
+ /*
+ * Note that this loop will end after one iteration given that there is
+ * only one kernel consumer.
+ */
+ 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 rotate it. */
+ cds_list_for_each_entry(chan, &ksess->channel_list.head, list) {
+ DBG("Rotate kernel channel %" PRIu64 ", session %s",
+ chan->key, session->name);
+ ret = consumer_rotate_channel(socket, chan->key,
+ ksess->uid, ksess->gid, ksess->consumer,
+ ksess->consumer->subdir,
+ /* is_metadata_channel */ false,
+ session->current_archive_id);
+ if (ret < 0) {
+ status = LTTNG_ERR_KERN_CONSUMER_FAIL;
+ goto error;
+ }
+ }
+
+ /*
+ * Rotate the metadata channel.
+ */
+ ret = consumer_rotate_channel(socket, ksess->metadata->key,
+ ksess->uid, ksess->gid, ksess->consumer,
+ ksess->consumer->subdir,
+ /* is_metadata_channel */ true,
+ session->current_archive_id);
+ if (ret < 0) {
+ status = LTTNG_ERR_KERN_CONSUMER_FAIL;
+ goto error;
+ }
+ }
+
+error:
+ rcu_read_unlock();
+ return status;
+}
projects / lttng-tools.git / blobdiff