--- /dev/null
+/*
+ * Copyright (C) 2011 David Goulet <david.goulet@polymtl.ca>
+ * Copyright (C) 2016 Jérémie Galarneau <jeremie.galarneau@efficios.com>
+ *
+ * SPDX-License-Identifier: GPL-2.0-only
+ *
+ */
+
+#define _LGPL_SOURCE
+#include <inttypes.h>
+#include <string.h>
+#include <unistd.h>
+
+#include <common/common.h>
+#include <common/defaults.h>
+#include <common/sessiond-comm/sessiond-comm.h>
+
+#include "channel.h"
+#include "lttng-sessiond.h"
+#include "kernel.h"
+#include "lttng-ust-ctl.h"
+#include "lttng-ust-error.h"
+#include "utils.h"
+#include "ust-app.h"
+#include "agent.h"
+
+/*
+ * Return allocated channel attributes.
+ */
+struct lttng_channel *channel_new_default_attr(int dom,
+ enum lttng_buffer_type type)
+{
+ struct lttng_channel *chan;
+ const char *channel_name = DEFAULT_CHANNEL_NAME;
+ struct lttng_channel_extended *extended_attr = NULL;
+
+ chan = (lttng_channel *) zmalloc(sizeof(struct lttng_channel));
+ if (chan == NULL) {
+ PERROR("zmalloc channel init");
+ goto error_alloc;
+ }
+
+ extended_attr = (lttng_channel_extended *) zmalloc(sizeof(struct lttng_channel_extended));
+ if (!extended_attr) {
+ PERROR("zmalloc channel extended init");
+ goto error;
+ }
+
+ chan->attr.extended.ptr = extended_attr;
+
+ /* Same for all domains. */
+ chan->attr.overwrite = DEFAULT_CHANNEL_OVERWRITE;
+ chan->attr.tracefile_size = DEFAULT_CHANNEL_TRACEFILE_SIZE;
+ chan->attr.tracefile_count = DEFAULT_CHANNEL_TRACEFILE_COUNT;
+
+ switch (dom) {
+ case LTTNG_DOMAIN_KERNEL:
+ LTTNG_ASSERT(type == LTTNG_BUFFER_GLOBAL);
+ chan->attr.subbuf_size =
+ default_get_kernel_channel_subbuf_size();
+ chan->attr.num_subbuf = DEFAULT_KERNEL_CHANNEL_SUBBUF_NUM;
+ chan->attr.output = DEFAULT_KERNEL_CHANNEL_OUTPUT;
+ chan->attr.switch_timer_interval = DEFAULT_KERNEL_CHANNEL_SWITCH_TIMER;
+ chan->attr.read_timer_interval = DEFAULT_KERNEL_CHANNEL_READ_TIMER;
+ chan->attr.live_timer_interval = DEFAULT_KERNEL_CHANNEL_LIVE_TIMER;
+ extended_attr->blocking_timeout = DEFAULT_KERNEL_CHANNEL_BLOCKING_TIMEOUT;
+ extended_attr->monitor_timer_interval =
+ DEFAULT_KERNEL_CHANNEL_MONITOR_TIMER;
+ break;
+ case LTTNG_DOMAIN_JUL:
+ channel_name = DEFAULT_JUL_CHANNEL_NAME;
+ goto common_ust;
+ case LTTNG_DOMAIN_LOG4J:
+ channel_name = DEFAULT_LOG4J_CHANNEL_NAME;
+ goto common_ust;
+ case LTTNG_DOMAIN_PYTHON:
+ channel_name = DEFAULT_PYTHON_CHANNEL_NAME;
+ goto common_ust;
+ case LTTNG_DOMAIN_UST:
+common_ust:
+ switch (type) {
+ case LTTNG_BUFFER_PER_UID:
+ chan->attr.subbuf_size = default_get_ust_uid_channel_subbuf_size();
+ chan->attr.num_subbuf = DEFAULT_UST_UID_CHANNEL_SUBBUF_NUM;
+ chan->attr.output = DEFAULT_UST_UID_CHANNEL_OUTPUT;
+ chan->attr.switch_timer_interval =
+ DEFAULT_UST_UID_CHANNEL_SWITCH_TIMER;
+ chan->attr.read_timer_interval =
+ DEFAULT_UST_UID_CHANNEL_READ_TIMER;
+ chan->attr.live_timer_interval =
+ DEFAULT_UST_UID_CHANNEL_LIVE_TIMER;
+ extended_attr->blocking_timeout = DEFAULT_UST_UID_CHANNEL_BLOCKING_TIMEOUT;
+ extended_attr->monitor_timer_interval =
+ DEFAULT_UST_UID_CHANNEL_MONITOR_TIMER;
+ break;
+ case LTTNG_BUFFER_PER_PID:
+ default:
+ chan->attr.subbuf_size = default_get_ust_pid_channel_subbuf_size();
+ chan->attr.num_subbuf = DEFAULT_UST_PID_CHANNEL_SUBBUF_NUM;
+ chan->attr.output = DEFAULT_UST_PID_CHANNEL_OUTPUT;
+ chan->attr.switch_timer_interval =
+ DEFAULT_UST_PID_CHANNEL_SWITCH_TIMER;
+ chan->attr.read_timer_interval =
+ DEFAULT_UST_PID_CHANNEL_READ_TIMER;
+ chan->attr.live_timer_interval =
+ DEFAULT_UST_PID_CHANNEL_LIVE_TIMER;
+ extended_attr->blocking_timeout = DEFAULT_UST_PID_CHANNEL_BLOCKING_TIMEOUT;
+ extended_attr->monitor_timer_interval =
+ DEFAULT_UST_PID_CHANNEL_MONITOR_TIMER;
+ break;
+ }
+ break;
+ default:
+ goto error; /* Not implemented */
+ }
+
+ if (snprintf(chan->name, sizeof(chan->name), "%s",
+ channel_name) < 0) {
+ PERROR("snprintf default channel name");
+ goto error;
+ }
+ return chan;
+
+error:
+ free(extended_attr);
+ free(chan);
+error_alloc:
+ return NULL;
+}
+
+void channel_attr_destroy(struct lttng_channel *channel)
+{
+ if (!channel) {
+ return;
+ }
+ free(channel->attr.extended.ptr);
+ free(channel);
+}
+
+/*
+ * Disable kernel channel of the kernel session.
+ */
+int channel_kernel_disable(struct ltt_kernel_session *ksession,
+ char *channel_name)
+{
+ int ret;
+ struct ltt_kernel_channel *kchan;
+
+ LTTNG_ASSERT(ksession);
+ LTTNG_ASSERT(channel_name);
+
+ kchan = trace_kernel_get_channel_by_name(channel_name, ksession);
+ if (kchan == NULL) {
+ ret = LTTNG_ERR_KERN_CHAN_NOT_FOUND;
+ goto error;
+ }
+
+ /* Only if channel is enabled disable it. */
+ if (kchan->enabled == 1) {
+ ret = kernel_disable_channel(kchan);
+ if (ret < 0 && ret != -EEXIST) {
+ ret = LTTNG_ERR_KERN_CHAN_DISABLE_FAIL;
+ goto error;
+ }
+ }
+
+ ret = LTTNG_OK;
+
+error:
+ return ret;
+}
+
+/*
+ * Enable kernel channel of the kernel session.
+ */
+int channel_kernel_enable(struct ltt_kernel_session *ksession,
+ struct ltt_kernel_channel *kchan)
+{
+ int ret;
+
+ LTTNG_ASSERT(ksession);
+ LTTNG_ASSERT(kchan);
+
+ if (kchan->enabled == 0) {
+ ret = kernel_enable_channel(kchan);
+ if (ret < 0) {
+ ret = LTTNG_ERR_KERN_CHAN_ENABLE_FAIL;
+ goto error;
+ }
+ } else {
+ ret = LTTNG_ERR_KERN_CHAN_EXIST;
+ goto error;
+ }
+
+ ret = LTTNG_OK;
+
+error:
+ return ret;
+}
+
+static int channel_validate(struct lttng_channel *attr)
+{
+ /*
+ * The ringbuffer (both in user space and kernel) behaves badly
+ * in overwrite mode and with less than 2 subbuffers so block it
+ * right away and send back an invalid attribute error.
+ */
+ if (attr->attr.overwrite && attr->attr.num_subbuf < 2) {
+ return -1;
+ }
+ return 0;
+}
+
+static int channel_validate_kernel(struct lttng_channel *attr)
+{
+ /* Kernel channels do not support blocking timeout. */
+ if (((struct lttng_channel_extended *)attr->attr.extended.ptr)->blocking_timeout) {
+ return -1;
+ }
+ return 0;
+}
+
+/*
+ * Create kernel channel of the kernel session and notify kernel thread.
+ */
+int channel_kernel_create(struct ltt_kernel_session *ksession,
+ struct lttng_channel *attr, int kernel_pipe)
+{
+ int ret;
+ struct lttng_channel *defattr = NULL;
+
+ LTTNG_ASSERT(ksession);
+
+ /* Creating channel attributes if needed */
+ if (attr == NULL) {
+ defattr = channel_new_default_attr(LTTNG_DOMAIN_KERNEL,
+ LTTNG_BUFFER_GLOBAL);
+ if (defattr == NULL) {
+ ret = LTTNG_ERR_FATAL;
+ goto error;
+ }
+ attr = defattr;
+ }
+
+ /*
+ * Set the overwrite mode for this channel based on the session
+ * type unless the client explicitly overrides the channel mode.
+ */
+ if (attr->attr.overwrite == DEFAULT_CHANNEL_OVERWRITE) {
+ attr->attr.overwrite = !!ksession->snapshot_mode;
+ }
+
+ /* Validate common channel properties. */
+ if (channel_validate(attr) < 0) {
+ ret = LTTNG_ERR_INVALID;
+ goto error;
+ }
+
+ if (channel_validate_kernel(attr) < 0) {
+ ret = LTTNG_ERR_INVALID;
+ goto error;
+ }
+
+ /* Channel not found, creating it */
+ ret = kernel_create_channel(ksession, attr);
+ if (ret < 0) {
+ ret = LTTNG_ERR_KERN_CHAN_FAIL;
+ goto error;
+ }
+
+ /* Notify kernel thread that there is a new channel */
+ ret = notify_thread_pipe(kernel_pipe);
+ if (ret < 0) {
+ ret = LTTNG_ERR_FATAL;
+ goto error;
+ }
+
+ ret = LTTNG_OK;
+error:
+ channel_attr_destroy(defattr);
+ return ret;
+}
+
+/*
+ * Enable UST channel for session and domain.
+ */
+int channel_ust_enable(struct ltt_ust_session *usess,
+ struct ltt_ust_channel *uchan)
+{
+ int ret = LTTNG_OK;
+
+ LTTNG_ASSERT(usess);
+ LTTNG_ASSERT(uchan);
+
+ /* If already enabled, everything is OK */
+ if (uchan->enabled) {
+ DBG3("Channel %s already enabled. Skipping", uchan->name);
+ ret = LTTNG_ERR_UST_CHAN_EXIST;
+ goto end;
+ } else {
+ uchan->enabled = 1;
+ DBG2("Channel %s enabled successfully", uchan->name);
+ }
+
+ if (!usess->active) {
+ /*
+ * The channel will be activated against the apps
+ * when the session is started as part of the
+ * application channel "synchronize" operation.
+ */
+ goto end;
+ }
+
+ DBG2("Channel %s being enabled in UST domain", uchan->name);
+
+ /*
+ * Enable channel for UST global domain on all applications. Ignore return
+ * value here since whatever error we got, it means that the channel was
+ * not created on one or many registered applications and we can not report
+ * this to the user yet. However, at this stage, the channel was
+ * successfully created on the session daemon side so the enable-channel
+ * command is a success.
+ */
+ (void) ust_app_enable_channel_glb(usess, uchan);
+
+
+end:
+ return ret;
+}
+
+/*
+ * Create UST channel for session and domain.
+ */
+int channel_ust_create(struct ltt_ust_session *usess,
+ struct lttng_channel *attr, enum lttng_buffer_type type)
+{
+ int ret = LTTNG_OK;
+ struct ltt_ust_channel *uchan = NULL;
+ struct lttng_channel *defattr = NULL;
+ enum lttng_domain_type domain = LTTNG_DOMAIN_UST;
+ bool chan_published = false;
+
+ LTTNG_ASSERT(usess);
+
+ /* Creating channel attributes if needed */
+ if (attr == NULL) {
+ defattr = channel_new_default_attr(LTTNG_DOMAIN_UST, type);
+ if (defattr == NULL) {
+ ret = LTTNG_ERR_FATAL;
+ goto error;
+ }
+ attr = defattr;
+ } else {
+ /*
+ * HACK: Set the channel's subdomain (JUL, Log4j, Python, etc.)
+ * based on the default name.
+ */
+ if (!strcmp(attr->name, DEFAULT_JUL_CHANNEL_NAME)) {
+ domain = LTTNG_DOMAIN_JUL;
+ } else if (!strcmp(attr->name, DEFAULT_LOG4J_CHANNEL_NAME)) {
+ domain = LTTNG_DOMAIN_LOG4J;
+ } else if (!strcmp(attr->name, DEFAULT_PYTHON_CHANNEL_NAME)) {
+ domain = LTTNG_DOMAIN_PYTHON;
+ }
+ }
+
+ /*
+ * Set the overwrite mode for this channel based on the session
+ * type unless the client explicitly overrides the channel mode.
+ */
+ if (attr->attr.overwrite == DEFAULT_CHANNEL_OVERWRITE) {
+ attr->attr.overwrite = !!usess->snapshot_mode;
+ }
+
+ /* Enforce mmap output for snapshot sessions. */
+ if (usess->snapshot_mode) {
+ attr->attr.output = LTTNG_EVENT_MMAP;
+ }
+
+ /* Validate common channel properties. */
+ if (channel_validate(attr) < 0) {
+ ret = LTTNG_ERR_INVALID;
+ goto error;
+ }
+
+ /*
+ * Validate UST buffer size and number of buffers: must both be power of 2
+ * and nonzero. We validate right here for UST, because applications will
+ * not report the error to the user (unlike kernel tracing).
+ */
+ if (!attr->attr.subbuf_size ||
+ (attr->attr.subbuf_size & (attr->attr.subbuf_size - 1))) {
+ ret = LTTNG_ERR_INVALID;
+ goto error;
+ }
+
+ /*
+ * Invalid subbuffer size if it's lower then the page size.
+ */
+ if (attr->attr.subbuf_size < the_page_size) {
+ ret = LTTNG_ERR_INVALID;
+ goto error;
+ }
+
+ if (!attr->attr.num_subbuf ||
+ (attr->attr.num_subbuf & (attr->attr.num_subbuf - 1))) {
+ ret = LTTNG_ERR_INVALID;
+ goto error;
+ }
+
+ if (attr->attr.output != LTTNG_EVENT_MMAP) {
+ ret = LTTNG_ERR_NOT_SUPPORTED;
+ goto error;
+ }
+
+ /*
+ * The tracefile_size should not be < to the subbuf_size, otherwise
+ * we won't be able to write the packets on disk
+ */
+ if ((attr->attr.tracefile_size > 0) &&
+ (attr->attr.tracefile_size < attr->attr.subbuf_size)) {
+ ret = LTTNG_ERR_INVALID;
+ goto error;
+ }
+
+ /* Validate buffer type. */
+ switch (type) {
+ case LTTNG_BUFFER_PER_PID:
+ break;
+ case LTTNG_BUFFER_PER_UID:
+ break;
+ default:
+ ret = LTTNG_ERR_BUFFER_NOT_SUPPORTED;
+ goto error;
+ }
+
+ /* Create UST channel */
+ uchan = trace_ust_create_channel(attr, domain);
+ if (uchan == NULL) {
+ ret = LTTNG_ERR_FATAL;
+ goto error;
+ }
+
+ uchan->enabled = 1;
+ if (trace_ust_is_max_id(usess->used_channel_id)) {
+ ret = LTTNG_ERR_UST_CHAN_FAIL;
+ goto error;
+ }
+ uchan->id = trace_ust_get_next_chan_id(usess);
+
+ DBG2("Channel %s is being created for UST with buffer %d and id %" PRIu64,
+ uchan->name, type, uchan->id);
+
+ /* Flag session buffer type. */
+ if (!usess->buffer_type_changed) {
+ usess->buffer_type = type;
+ usess->buffer_type_changed = 1;
+ } else if (usess->buffer_type != type) {
+ /* Buffer type was already set. Refuse to create channel. */
+ ret = LTTNG_ERR_BUFFER_TYPE_MISMATCH;
+ goto error_free_chan;
+ }
+
+ /* Adding the channel to the channel hash table. */
+ rcu_read_lock();
+ if (strncmp(uchan->name, DEFAULT_METADATA_NAME,
+ sizeof(uchan->name))) {
+ lttng_ht_add_unique_str(usess->domain_global.channels, &uchan->node);
+ chan_published = true;
+ } else {
+ /*
+ * Copy channel attribute to session if this is metadata so if NO
+ * application exists we can access that data in the shadow copy during
+ * the global update of newly registered application.
+ */
+ memcpy(&usess->metadata_attr, &uchan->attr,
+ sizeof(usess->metadata_attr));
+ }
+ rcu_read_unlock();
+
+ DBG2("Channel %s created successfully", uchan->name);
+ if (domain != LTTNG_DOMAIN_UST) {
+ struct agent *agt = trace_ust_find_agent(usess, domain);
+
+ if (!agt) {
+ agt = agent_create(domain);
+ if (!agt) {
+ ret = LTTNG_ERR_NOMEM;
+ goto error_remove_chan;
+ }
+ agent_add(agt, usess->agents);
+ }
+ }
+
+ channel_attr_destroy(defattr);
+ return LTTNG_OK;
+
+error_remove_chan:
+ if (chan_published) {
+ trace_ust_delete_channel(usess->domain_global.channels, uchan);
+ }
+error_free_chan:
+ trace_ust_destroy_channel(uchan);
+error:
+ channel_attr_destroy(defattr);
+ return ret;
+}
+
+/*
+ * Disable UST channel for session and domain.
+ */
+int channel_ust_disable(struct ltt_ust_session *usess,
+ struct ltt_ust_channel *uchan)
+{
+ int ret = LTTNG_OK;
+
+ LTTNG_ASSERT(usess);
+ LTTNG_ASSERT(uchan);
+
+ /* Already disabled */
+ if (uchan->enabled == 0) {
+ DBG2("Channel UST %s already disabled", uchan->name);
+ goto end;
+ }
+
+ uchan->enabled = 0;
+
+ /*
+ * If session is inactive we don't notify the tracer right away. We
+ * wait for the next synchronization.
+ */
+ if (!usess->active) {
+ goto end;
+ }
+
+ DBG2("Channel %s being disabled in UST global domain", uchan->name);
+ /* Disable channel for global domain */
+ ret = ust_app_disable_channel_glb(usess, uchan);
+ if (ret < 0 && ret != -LTTNG_UST_ERR_EXIST) {
+ ret = LTTNG_ERR_UST_CHAN_DISABLE_FAIL;
+ goto error;
+ }
+
+ DBG2("Channel %s disabled successfully", uchan->name);
+
+ return LTTNG_OK;
+
+end:
+error:
+ return ret;
+}
projects / lttng-tools.git / blobdiff