--- /dev/null
+/*
+ * Copyright (C) 2013 - Julien Desfossez <jdesfossez@efficios.com>
+ * David Goulet <dgoulet@efficios.com>
+ *
+ * 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.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+
+#define _LGPL_SOURCE
+#include <assert.h>
+#include <pthread.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/types.h>
+#include <unistd.h>
+#include <inttypes.h>
+
+#include <common/common.h>
+#include <common/utils.h>
+#include <common/sessiond-comm/sessiond-comm.h>
+#include <common/ust-consumer/ust-consumer.h>
+#include <common/consumer/consumer.h>
+
+#include "consumer-metadata-cache.h"
+
+extern struct lttng_consumer_global_data consumer_data;
+
+/*
+ * Extend the allocated size of the metadata cache. Called only from
+ * lttng_ustconsumer_write_metadata_cache.
+ *
+ * Return 0 on success, a negative value on error.
+ */
+static int extend_metadata_cache(struct lttng_consumer_channel *channel,
+ unsigned int size)
+{
+ int ret = 0;
+ char *tmp_data_ptr;
+ unsigned int new_size, old_size;
+
+ assert(channel);
+ assert(channel->metadata_cache);
+
+ old_size = channel->metadata_cache->cache_alloc_size;
+ new_size = max_t(unsigned int, old_size + size, old_size << 1);
+ DBG("Extending metadata cache to %u", new_size);
+ tmp_data_ptr = realloc(channel->metadata_cache->data, new_size);
+ if (!tmp_data_ptr) {
+ ERR("Reallocating metadata cache");
+ free(channel->metadata_cache->data);
+ ret = -1;
+ goto end;
+ }
+ /* Zero newly allocated memory */
+ memset(tmp_data_ptr + old_size, 0, new_size - old_size);
+ channel->metadata_cache->data = tmp_data_ptr;
+ channel->metadata_cache->cache_alloc_size = new_size;
+
+end:
+ return ret;
+}
+
+/*
+ * Write metadata to the cache, extend the cache if necessary. We support
+ * overlapping updates, but they need to be contiguous. Send the
+ * contiguous metadata in cache to the ring buffer. The metadata cache
+ * lock MUST be acquired to write in the cache.
+ *
+ * Return 0 on success, a negative value on error.
+ */
+int consumer_metadata_cache_write(struct lttng_consumer_channel *channel,
+ unsigned int offset, unsigned int len, char *data)
+{
+ int ret = 0;
+ int size_ret;
+ struct consumer_metadata_cache *cache;
+
+ assert(channel);
+ assert(channel->metadata_cache);
+
+ cache = channel->metadata_cache;
+ DBG("Writing %u bytes from offset %u in metadata cache", len, offset);
+
+ if (offset + len > cache->cache_alloc_size) {
+ ret = extend_metadata_cache(channel,
+ len - cache->cache_alloc_size + offset);
+ if (ret < 0) {
+ ERR("Extending metadata cache");
+ goto end;
+ }
+ }
+
+ memcpy(cache->data + offset, data, len);
+ if (offset + len > cache->max_offset) {
+ char dummy = 'c';
+
+ cache->max_offset = offset + len;
+ if (channel->monitor) {
+ size_ret = lttng_write(channel->metadata_stream->ust_metadata_poll_pipe[1],
+ &dummy, 1);
+ if (size_ret < 1) {
+ ERR("Wakeup UST metadata pipe");
+ ret = -1;
+ goto end;
+ }
+ }
+ }
+
+end:
+ return ret;
+}
+
+/*
+ * Create the metadata cache, original allocated size: max_sb_size
+ *
+ * Return 0 on success, a negative value on error.
+ */
+int consumer_metadata_cache_allocate(struct lttng_consumer_channel *channel)
+{
+ int ret;
+
+ assert(channel);
+
+ channel->metadata_cache = zmalloc(
+ sizeof(struct consumer_metadata_cache));
+ if (!channel->metadata_cache) {
+ PERROR("zmalloc metadata cache struct");
+ ret = -1;
+ goto end;
+ }
+ ret = pthread_mutex_init(&channel->metadata_cache->lock, NULL);
+ if (ret != 0) {
+ PERROR("mutex init");
+ goto end_free_cache;
+ }
+
+ channel->metadata_cache->cache_alloc_size = DEFAULT_METADATA_CACHE_SIZE;
+ channel->metadata_cache->data = zmalloc(
+ channel->metadata_cache->cache_alloc_size * sizeof(char));
+ if (!channel->metadata_cache->data) {
+ PERROR("zmalloc metadata cache data");
+ ret = -1;
+ goto end_free_mutex;
+ }
+ DBG("Allocated metadata cache of %" PRIu64 " bytes",
+ channel->metadata_cache->cache_alloc_size);
+
+ ret = 0;
+ goto end;
+
+end_free_mutex:
+ pthread_mutex_destroy(&channel->metadata_cache->lock);
+end_free_cache:
+ free(channel->metadata_cache);
+end:
+ return ret;
+}
+
+/*
+ * Destroy and free the metadata cache
+ */
+void consumer_metadata_cache_destroy(struct lttng_consumer_channel *channel)
+{
+ if (!channel || !channel->metadata_cache) {
+ return;
+ }
+
+ DBG("Destroying metadata cache");
+
+ pthread_mutex_destroy(&channel->metadata_cache->lock);
+ free(channel->metadata_cache->data);
+ free(channel->metadata_cache);
+}
+
+/*
+ * Check if the cache is flushed up to the offset passed in parameter.
+ *
+ * Return 0 if everything has been flushed, 1 if there is data not flushed.
+ */
+int consumer_metadata_cache_flushed(struct lttng_consumer_channel *channel,
+ uint64_t offset, int timer)
+{
+ int ret = 0;
+ struct lttng_consumer_stream *metadata_stream;
+
+ assert(channel);
+ assert(channel->metadata_cache);
+
+ /*
+ * If not called from a timer handler, we have to take the
+ * channel lock to be mutually exclusive with channel teardown.
+ * Timer handler does not need to take this lock because it is
+ * already synchronized by timer stop (and, more importantly,
+ * taking this lock in a timer handler would cause a deadlock).
+ */
+ if (!timer) {
+ pthread_mutex_lock(&channel->lock);
+ }
+ pthread_mutex_lock(&channel->timer_lock);
+ pthread_mutex_lock(&channel->metadata_cache->lock);
+
+ metadata_stream = channel->metadata_stream;
+
+ if (!metadata_stream) {
+ /*
+ * Having no metadata stream means the channel is being destroyed so there
+ * is no cache to flush anymore.
+ */
+ ret = 0;
+ } else if (metadata_stream->ust_metadata_pushed >= offset) {
+ ret = 0;
+ } else if (channel->metadata_stream->endpoint_status !=
+ CONSUMER_ENDPOINT_ACTIVE) {
+ /* An inactive endpoint means we don't have to flush anymore. */
+ ret = 0;
+ } else {
+ /* Still not completely flushed. */
+ ret = 1;
+ }
+
+ pthread_mutex_unlock(&channel->metadata_cache->lock);
+ pthread_mutex_unlock(&channel->timer_lock);
+ if (!timer) {
+ pthread_mutex_unlock(&channel->lock);
+ }
+
+ return ret;
+}
projects / lttng-tools.git / blobdiff