-/*
- * Copyright (C) 2011 David Goulet <david.goulet@polymtl.ca>
- *
- * SPDX-License-Identifier: GPL-2.0-only
- *
- */
-
-#define _LGPL_SOURCE
-#include <stdio.h>
-#include <stdlib.h>
-#include <string.h>
-#include <unistd.h>
-
-#include <lttng/event.h>
-#include <lttng/lttng-error.h>
-#include <lttng/userspace-probe.h>
-#include <lttng/userspace-probe-internal.h>
-
-#include <common/common.h>
-#include <common/defaults.h>
-#include <common/trace-chunk.h>
-
-#include "consumer.h"
-#include "trace-kernel.h"
-#include "lttng-sessiond.h"
-#include "notification-thread-commands.h"
-
-/*
- * Find the channel name for the given kernel session.
- */
-struct ltt_kernel_channel *trace_kernel_get_channel_by_name(
- const char *name, struct ltt_kernel_session *session)
-{
- struct ltt_kernel_channel *chan;
-
- assert(session);
- assert(name);
-
- /*
- * If we receive an empty string for channel name, it means the
- * default channel name is requested.
- */
- if (name[0] == '\0')
- name = DEFAULT_CHANNEL_NAME;
-
- DBG("Trying to find channel %s", name);
-
- cds_list_for_each_entry(chan, &session->channel_list.head, list) {
- if (strcmp(name, chan->channel->name) == 0) {
- DBG("Found channel by name %s", name);
- return chan;
- }
- }
-
- return NULL;
-}
-
-/*
- * Find the event for the given channel.
- */
-struct ltt_kernel_event *trace_kernel_find_event(
- char *name, struct ltt_kernel_channel *channel,
- enum lttng_event_type type,
- struct lttng_filter_bytecode *filter)
-{
- struct ltt_kernel_event *ev;
- int found = 0;
-
- assert(name);
- assert(channel);
-
- cds_list_for_each_entry(ev, &channel->events_list.head, list) {
- if (type != LTTNG_EVENT_ALL && ev->type != type) {
- continue;
- }
- if (strcmp(name, ev->event->name)) {
- continue;
- }
- if ((ev->filter && !filter) || (!ev->filter && filter)) {
- continue;
- }
- if (ev->filter && filter) {
- if (ev->filter->len != filter->len ||
- memcmp(ev->filter->data, filter->data,
- filter->len) != 0) {
- continue;
- }
- }
- found = 1;
- break;
- }
- if (found) {
- DBG("Found event %s for channel %s", name,
- channel->channel->name);
- return ev;
- } else {
- return NULL;
- }
-}
-
-/*
- * Find the event name for the given channel.
- */
-struct ltt_kernel_event *trace_kernel_get_event_by_name(
- char *name, struct ltt_kernel_channel *channel,
- enum lttng_event_type type)
-{
- struct ltt_kernel_event *ev;
- int found = 0;
-
- assert(name);
- assert(channel);
-
- cds_list_for_each_entry(ev, &channel->events_list.head, list) {
- if (type != LTTNG_EVENT_ALL && ev->type != type) {
- continue;
- }
- if (strcmp(name, ev->event->name)) {
- continue;
- }
- found = 1;
- break;
- }
- if (found) {
- DBG("Found event %s for channel %s", name,
- channel->channel->name);
- return ev;
- } else {
- return NULL;
- }
-}
-
-/*
- * Allocate and initialize a kernel session data structure.
- *
- * Return pointer to structure or NULL.
- */
-struct ltt_kernel_session *trace_kernel_create_session(void)
-{
- struct ltt_kernel_session *lks = NULL;
-
- /* Allocate a new ltt kernel session */
- lks = zmalloc(sizeof(struct ltt_kernel_session));
- if (lks == NULL) {
- PERROR("create kernel session zmalloc");
- goto alloc_error;
- }
-
- /* Init data structure */
- lks->fd = -1;
- lks->metadata_stream_fd = -1;
- lks->channel_count = 0;
- lks->stream_count_global = 0;
- lks->metadata = NULL;
- CDS_INIT_LIST_HEAD(&lks->channel_list.head);
-
- lks->tracker_pid = process_attr_tracker_create();
- if (!lks->tracker_pid) {
- goto error;
- }
- lks->tracker_vpid = process_attr_tracker_create();
- if (!lks->tracker_vpid) {
- goto error;
- }
- lks->tracker_uid = process_attr_tracker_create();
- if (!lks->tracker_uid) {
- goto error;
- }
- lks->tracker_vuid = process_attr_tracker_create();
- if (!lks->tracker_vuid) {
- goto error;
- }
- lks->tracker_gid = process_attr_tracker_create();
- if (!lks->tracker_gid) {
- goto error;
- }
- lks->tracker_vgid = process_attr_tracker_create();
- if (!lks->tracker_vgid) {
- goto error;
- }
- lks->consumer = consumer_create_output(CONSUMER_DST_LOCAL);
- if (lks->consumer == NULL) {
- goto error;
- }
-
- return lks;
-
-error:
- process_attr_tracker_destroy(lks->tracker_pid);
- process_attr_tracker_destroy(lks->tracker_vpid);
- process_attr_tracker_destroy(lks->tracker_uid);
- process_attr_tracker_destroy(lks->tracker_vuid);
- process_attr_tracker_destroy(lks->tracker_gid);
- process_attr_tracker_destroy(lks->tracker_vgid);
- free(lks);
-
-alloc_error:
- return NULL;
-}
-
-/*
- * Allocate and initialize a kernel channel data structure.
- *
- * Return pointer to structure or NULL.
- */
-struct ltt_kernel_channel *trace_kernel_create_channel(
- struct lttng_channel *chan)
-{
- struct ltt_kernel_channel *lkc;
- struct lttng_channel_extended *extended = NULL;
-
- assert(chan);
-
- lkc = zmalloc(sizeof(struct ltt_kernel_channel));
- if (lkc == NULL) {
- PERROR("ltt_kernel_channel zmalloc");
- goto error;
- }
-
- lkc->channel = zmalloc(sizeof(struct lttng_channel));
- if (lkc->channel == NULL) {
- PERROR("lttng_channel zmalloc");
- goto error;
- }
-
- extended = zmalloc(sizeof(struct lttng_channel_extended));
- if (!extended) {
- PERROR("lttng_channel_channel zmalloc");
- goto error;
- }
- memcpy(lkc->channel, chan, sizeof(struct lttng_channel));
- memcpy(extended, chan->attr.extended.ptr, sizeof(struct lttng_channel_extended));
- lkc->channel->attr.extended.ptr = extended;
- extended = NULL;
-
- /*
- * If we receive an empty string for channel name, it means the
- * default channel name is requested.
- */
- if (chan->name[0] == '\0') {
- strncpy(lkc->channel->name, DEFAULT_CHANNEL_NAME,
- sizeof(lkc->channel->name));
- }
- lkc->channel->name[LTTNG_KERNEL_SYM_NAME_LEN - 1] = '\0';
-
- lkc->fd = -1;
- lkc->stream_count = 0;
- lkc->event_count = 0;
- lkc->enabled = 1;
- lkc->published_to_notification_thread = false;
- /* Init linked list */
- CDS_INIT_LIST_HEAD(&lkc->events_list.head);
- CDS_INIT_LIST_HEAD(&lkc->stream_list.head);
- CDS_INIT_LIST_HEAD(&lkc->ctx_list);
-
- return lkc;
-
-error:
- if (lkc) {
- free(lkc->channel);
- }
- free(extended);
- free(lkc);
- return NULL;
-}
-
-/*
- * Allocate and init a kernel context object.
- *
- * Return the allocated object or NULL on error.
- */
-struct ltt_kernel_context *trace_kernel_create_context(
- struct lttng_kernel_context *ctx)
-{
- struct ltt_kernel_context *kctx;
-
- kctx = zmalloc(sizeof(*kctx));
- if (!kctx) {
- PERROR("zmalloc kernel context");
- goto error;
- }
-
- if (ctx) {
- memcpy(&kctx->ctx, ctx, sizeof(kctx->ctx));
- }
-error:
- return kctx;
-}
-
-/*
- * Allocate and init a kernel context object from an existing kernel context
- * object.
- *
- * Return the allocated object or NULL on error.
- */
-struct ltt_kernel_context *trace_kernel_copy_context(
- struct ltt_kernel_context *kctx)
-{
- struct ltt_kernel_context *kctx_copy;
-
- assert(kctx);
- kctx_copy = zmalloc(sizeof(*kctx_copy));
- if (!kctx_copy) {
- PERROR("zmalloc ltt_kernel_context");
- goto error;
- }
-
- memcpy(kctx_copy, kctx, sizeof(*kctx_copy));
- memset(&kctx_copy->list, 0, sizeof(kctx_copy->list));
-
-error:
- return kctx_copy;
-}
-
-/*
- * Allocate and initialize a kernel event. Set name and event type.
- * We own filter_expression, and filter.
- *
- * Return pointer to structure or NULL.
- */
-enum lttng_error_code trace_kernel_create_event(
- struct lttng_event *ev, char *filter_expression,
- struct lttng_filter_bytecode *filter,
- struct ltt_kernel_event **kernel_event)
-{
- enum lttng_error_code ret;
- struct lttng_kernel_event *attr;
- struct ltt_kernel_event *local_kernel_event;
- struct lttng_userspace_probe_location *userspace_probe_location = NULL;
-
- assert(ev);
-
- local_kernel_event = zmalloc(sizeof(struct ltt_kernel_event));
- attr = zmalloc(sizeof(struct lttng_kernel_event));
- if (local_kernel_event == NULL || attr == NULL) {
- PERROR("kernel event zmalloc");
- ret = LTTNG_ERR_NOMEM;
- goto error;
- }
-
- switch (ev->type) {
- case LTTNG_EVENT_PROBE:
- attr->instrumentation = LTTNG_KERNEL_KPROBE;
- attr->u.kprobe.addr = ev->attr.probe.addr;
- attr->u.kprobe.offset = ev->attr.probe.offset;
- strncpy(attr->u.kprobe.symbol_name,
- ev->attr.probe.symbol_name, LTTNG_KERNEL_SYM_NAME_LEN);
- attr->u.kprobe.symbol_name[LTTNG_KERNEL_SYM_NAME_LEN - 1] = '\0';
- break;
- case LTTNG_EVENT_USERSPACE_PROBE:
- {
- const struct lttng_userspace_probe_location* location = NULL;
- const struct lttng_userspace_probe_location_lookup_method *lookup = NULL;
-
- location = lttng_event_get_userspace_probe_location(ev);
- if (!location) {
- ret = LTTNG_ERR_PROBE_LOCATION_INVAL;
- goto error;
- }
-
- /*
- * From this point on, the specific term 'uprobe' is used
- * instead of the generic 'userspace probe' because it's the
- * technology used at the moment for this instrumentation.
- * LTTng currently implements userspace probes using uprobes.
- * In the interactions with the kernel tracer, we use the
- * uprobe term.
- */
- attr->instrumentation = LTTNG_KERNEL_UPROBE;
-
- /*
- * Only the elf lookup method is supported at the moment.
- */
- lookup = lttng_userspace_probe_location_get_lookup_method(
- location);
- if (!lookup) {
- ret = LTTNG_ERR_PROBE_LOCATION_INVAL;
- goto error;
- }
-
- /*
- * From the kernel tracer's perspective, all userspace probe
- * event types are all the same: a file and an offset.
- */
- switch (lttng_userspace_probe_location_lookup_method_get_type(lookup)) {
- case LTTNG_USERSPACE_PROBE_LOCATION_LOOKUP_METHOD_TYPE_FUNCTION_ELF:
- /* Get the file descriptor on the target binary. */
- attr->u.uprobe.fd =
- lttng_userspace_probe_location_function_get_binary_fd(location);
-
- /*
- * Save a reference to the probe location used during
- * the listing of events. Close its FD since it won't
- * be needed for listing.
- */
- userspace_probe_location =
- lttng_userspace_probe_location_copy(location);
- ret = lttng_userspace_probe_location_function_set_binary_fd(
- userspace_probe_location, -1);
- if (ret) {
- goto error;
- }
- break;
- case LTTNG_USERSPACE_PROBE_LOCATION_LOOKUP_METHOD_TYPE_TRACEPOINT_SDT:
- /* Get the file descriptor on the target binary. */
- attr->u.uprobe.fd =
- lttng_userspace_probe_location_tracepoint_get_binary_fd(location);
-
- /*
- * Save a reference to the probe location used during the listing of
- * events. Close its FD since it won't be needed for listing.
- */
- userspace_probe_location =
- lttng_userspace_probe_location_copy(location);
- ret = lttng_userspace_probe_location_tracepoint_set_binary_fd(
- userspace_probe_location, -1);
- if (ret) {
- goto error;
- }
- break;
- default:
- DBG("Unsupported lookup method type");
- ret = LTTNG_ERR_PROBE_LOCATION_INVAL;
- goto error;
- }
- break;
- }
- case LTTNG_EVENT_FUNCTION:
- attr->instrumentation = LTTNG_KERNEL_KRETPROBE;
- attr->u.kretprobe.addr = ev->attr.probe.addr;
- attr->u.kretprobe.offset = ev->attr.probe.offset;
- strncpy(attr->u.kretprobe.symbol_name,
- ev->attr.probe.symbol_name, LTTNG_KERNEL_SYM_NAME_LEN);
- attr->u.kretprobe.symbol_name[LTTNG_KERNEL_SYM_NAME_LEN - 1] = '\0';
- break;
- case LTTNG_EVENT_FUNCTION_ENTRY:
- attr->instrumentation = LTTNG_KERNEL_FUNCTION;
- strncpy(attr->u.ftrace.symbol_name,
- ev->attr.ftrace.symbol_name, LTTNG_KERNEL_SYM_NAME_LEN);
- attr->u.ftrace.symbol_name[LTTNG_KERNEL_SYM_NAME_LEN - 1] = '\0';
- break;
- case LTTNG_EVENT_TRACEPOINT:
- attr->instrumentation = LTTNG_KERNEL_TRACEPOINT;
- break;
- case LTTNG_EVENT_SYSCALL:
- attr->instrumentation = LTTNG_KERNEL_SYSCALL;
- break;
- case LTTNG_EVENT_ALL:
- attr->instrumentation = LTTNG_KERNEL_ALL;
- break;
- default:
- ERR("Unknown kernel instrumentation type (%d)", ev->type);
- ret = LTTNG_ERR_INVALID;
- goto error;
- }
-
- /* Copy event name */
- strncpy(attr->name, ev->name, LTTNG_KERNEL_SYM_NAME_LEN);
- attr->name[LTTNG_KERNEL_SYM_NAME_LEN - 1] = '\0';
-
- /* Setting up a kernel event */
- local_kernel_event->fd = -1;
- local_kernel_event->event = attr;
- local_kernel_event->enabled = 1;
- local_kernel_event->filter_expression = filter_expression;
- local_kernel_event->filter = filter;
- local_kernel_event->userspace_probe_location = userspace_probe_location;
-
- *kernel_event = local_kernel_event;
-
- return LTTNG_OK;
-
-error:
- free(filter_expression);
- free(filter);
- free(local_kernel_event);
- free(attr);
- return ret;
-}
-
-/*
- * Allocate and initialize a kernel metadata.
- *
- * Return pointer to structure or NULL.
- */
-struct ltt_kernel_metadata *trace_kernel_create_metadata(void)
-{
- struct ltt_kernel_metadata *lkm;
- struct lttng_channel *chan;
-
- lkm = zmalloc(sizeof(struct ltt_kernel_metadata));
- chan = zmalloc(sizeof(struct lttng_channel));
- if (lkm == NULL || chan == NULL) {
- PERROR("kernel metadata zmalloc");
- goto error;
- }
-
- /* Set default attributes */
- chan->attr.overwrite = DEFAULT_CHANNEL_OVERWRITE;
- chan->attr.subbuf_size = default_get_metadata_subbuf_size();
- chan->attr.num_subbuf = DEFAULT_METADATA_SUBBUF_NUM;
- chan->attr.switch_timer_interval = DEFAULT_KERNEL_CHANNEL_SWITCH_TIMER;
- chan->attr.read_timer_interval = DEFAULT_KERNEL_CHANNEL_READ_TIMER;
- chan->attr.output = DEFAULT_KERNEL_CHANNEL_OUTPUT;
-
- /* Init metadata */
- lkm->fd = -1;
- lkm->conf = chan;
-
- return lkm;
-
-error:
- free(lkm);
- free(chan);
- return NULL;
-}
-
-/*
- * Allocate and initialize a kernel stream. The stream is set to ACTIVE_FD by
- * default.
- *
- * Return pointer to structure or NULL.
- */
-struct ltt_kernel_stream *trace_kernel_create_stream(const char *name,
- unsigned int count)
-{
- int ret;
- struct ltt_kernel_stream *lks;
-
- assert(name);
-
- lks = zmalloc(sizeof(struct ltt_kernel_stream));
- if (lks == NULL) {
- PERROR("kernel stream zmalloc");
- goto error;
- }
-
- /* Set name */
- ret = snprintf(lks->name, sizeof(lks->name), "%s_%u", name, count);
- if (ret < 0) {
- PERROR("snprintf stream name");
- goto error;
- }
- lks->name[sizeof(lks->name) - 1] = '\0';
-
- /* Init stream */
- lks->fd = -1;
- lks->state = 0;
- lks->cpu = count;
-
- return lks;
-
-error:
- return NULL;
-}
-
-/*
- * Cleanup kernel stream structure.
- */
-void trace_kernel_destroy_stream(struct ltt_kernel_stream *stream)
-{
- assert(stream);
-
- DBG("[trace] Closing stream fd %d", stream->fd);
- /* Close kernel fd */
- if (stream->fd >= 0) {
- int ret;
-
- ret = close(stream->fd);
- if (ret) {
- PERROR("close");
- }
- }
- /* Remove from stream list */
- cds_list_del(&stream->list);
-
- free(stream);
-}
-
-/*
- * Cleanup kernel event structure.
- */
-void trace_kernel_destroy_event(struct ltt_kernel_event *event)
-{
- assert(event);
-
- if (event->fd >= 0) {
- int ret;
-
- DBG("[trace] Closing event fd %d", event->fd);
- /* Close kernel fd */
- ret = close(event->fd);
- if (ret) {
- PERROR("close");
- }
- } else {
- DBG("[trace] Tearing down event (no associated fd)");
- }
-
- /* Remove from event list */
- cds_list_del(&event->list);
-
- free(event->filter_expression);
- free(event->filter);
-
- free(event->event);
- free(event);
-}
-
-/*
- * Cleanup kernel context structure.
- */
-void trace_kernel_destroy_context(struct ltt_kernel_context *ctx)
-{
- assert(ctx);
-
- if (ctx->in_list) {
- cds_list_del(&ctx->list);
- }
- free(ctx);
-}
-
-/*
- * Cleanup kernel channel structure.
- */
-void trace_kernel_destroy_channel(struct ltt_kernel_channel *channel)
-{
- struct ltt_kernel_stream *stream, *stmp;
- struct ltt_kernel_event *event, *etmp;
- struct ltt_kernel_context *ctx, *ctmp;
- int ret;
- enum lttng_error_code status;
-
- assert(channel);
-
- DBG("[trace] Closing channel fd %d", channel->fd);
- /* Close kernel fd */
- if (channel->fd >= 0) {
- ret = close(channel->fd);
- if (ret) {
- PERROR("close");
- }
- }
-
- /* For each stream in the channel list */
- cds_list_for_each_entry_safe(stream, stmp, &channel->stream_list.head, list) {
- trace_kernel_destroy_stream(stream);
- }
-
- /* For each event in the channel list */
- cds_list_for_each_entry_safe(event, etmp, &channel->events_list.head, list) {
- trace_kernel_destroy_event(event);
- }
-
- /* For each context in the channel list */
- cds_list_for_each_entry_safe(ctx, ctmp, &channel->ctx_list, list) {
- trace_kernel_destroy_context(ctx);
- }
-
- /* Remove from channel list */
- cds_list_del(&channel->list);
-
- if (notification_thread_handle
- && channel->published_to_notification_thread) {
- status = notification_thread_command_remove_channel(
- notification_thread_handle,
- channel->key, LTTNG_DOMAIN_KERNEL);
- assert(status == LTTNG_OK);
- }
- free(channel->channel->attr.extended.ptr);
- free(channel->channel);
- free(channel);
-}
-
-/*
- * Cleanup kernel metadata structure.
- */
-void trace_kernel_destroy_metadata(struct ltt_kernel_metadata *metadata)
-{
- assert(metadata);
-
- DBG("[trace] Closing metadata fd %d", metadata->fd);
- /* Close kernel fd */
- if (metadata->fd >= 0) {
- int ret;
-
- ret = close(metadata->fd);
- if (ret) {
- PERROR("close");
- }
- }
-
- free(metadata->conf);
- free(metadata);
-}
-
-/*
- * Cleanup kernel session structure
- *
- * Should *NOT* be called with RCU read-side lock held.
- */
-void trace_kernel_destroy_session(struct ltt_kernel_session *session)
-{
- struct ltt_kernel_channel *channel, *ctmp;
- int ret;
-
- assert(session);
-
- DBG("[trace] Closing session fd %d", session->fd);
- /* Close kernel fds */
- if (session->fd >= 0) {
- ret = close(session->fd);
- if (ret) {
- PERROR("close");
- }
- }
-
- if (session->metadata_stream_fd >= 0) {
- DBG("[trace] Closing metadata stream fd %d", session->metadata_stream_fd);
- ret = close(session->metadata_stream_fd);
- if (ret) {
- PERROR("close");
- }
- }
-
- if (session->metadata != NULL) {
- trace_kernel_destroy_metadata(session->metadata);
- }
-
- cds_list_for_each_entry_safe(channel, ctmp, &session->channel_list.head, list) {
- trace_kernel_destroy_channel(channel);
- }
-}
-
-/* Free elements needed by destroy notifiers. */
-void trace_kernel_free_session(struct ltt_kernel_session *session)
-{
- /* Wipe consumer output object */
- consumer_output_put(session->consumer);
-
- process_attr_tracker_destroy(session->tracker_pid);
- process_attr_tracker_destroy(session->tracker_vpid);
- process_attr_tracker_destroy(session->tracker_uid);
- process_attr_tracker_destroy(session->tracker_vuid);
- process_attr_tracker_destroy(session->tracker_gid);
- process_attr_tracker_destroy(session->tracker_vgid);
-
- free(session);
-}