+++ /dev/null
-/*
- * Copyright (C) 2013 Julien Desfossez <jdesfossez@efficios.com>
- * Copyright (C) 2013 David Goulet <dgoulet@efficios.com>
- *
- * SPDX-License-Identifier: GPL-2.0-only
- *
- */
-
-#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;
-}
-
-/*
- * Reset the metadata cache.
- */
-static
-void metadata_cache_reset(struct consumer_metadata_cache *cache)
-{
- memset(cache->data, 0, cache->cache_alloc_size);
- cache->max_offset = 0;
-}
-
-/*
- * Check if the metadata cache version changed.
- * If it did, reset the metadata cache.
- * The metadata cache lock MUST be held.
- *
- * Returns 0 on success, a negative value on error.
- */
-static
-int metadata_cache_check_version(struct consumer_metadata_cache *cache,
- uint64_t version)
-{
- int ret = 0;
-
- if (cache->version == version) {
- goto end;
- }
-
- DBG("Metadata cache version update to %" PRIu64, version);
- metadata_cache_reset(cache);
- cache->version = version;
-
-end:
- return ret;
-}
-
-/*
- * Write a character on the metadata poll pipe to wake the metadata thread.
- * Returns 0 on success, -1 on error.
- */
-int consumer_metadata_wakeup_pipe(const struct lttng_consumer_channel *channel)
-{
- int ret = 0;
- const char dummy = 'c';
-
- if (channel->monitor && channel->metadata_stream) {
- ssize_t write_ret;
-
- write_ret = lttng_write(channel->metadata_stream->ust_metadata_poll_pipe[1],
- &dummy, 1);
- if (write_ret < 1) {
- if (errno == EWOULDBLOCK) {
- /*
- * This is fine, the metadata poll thread
- * is having a hard time keeping-up, but
- * it will eventually wake-up and consume
- * the available data.
- */
- ret = 0;
- } else {
- PERROR("Wake-up UST metadata pipe");
- ret = -1;
- goto end;
- }
- }
- }
-
-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, uint64_t version,
- char *data)
-{
- int ret = 0;
- struct consumer_metadata_cache *cache;
-
- assert(channel);
- assert(channel->metadata_cache);
-
- cache = channel->metadata_cache;
-
- ret = metadata_cache_check_version(cache, version);
- if (ret < 0) {
- goto end;
- }
-
- 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) {
- cache->max_offset = offset + len;
- ret = consumer_metadata_wakeup_pipe(channel);
- }
-
-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);
- 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;
- goto end_unlock_channel;
- }
-
- pthread_mutex_lock(&metadata_stream->lock);
- pthread_mutex_lock(&channel->metadata_cache->lock);
-
- 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(&metadata_stream->lock);
-end_unlock_channel:
- pthread_mutex_unlock(&channel->timer_lock);
- if (!timer) {
- pthread_mutex_unlock(&channel->lock);
- }
-
- return ret;
-}
projects / lttng-tools.git / blobdiff