struct ltt_channel_ops {
struct ltt_channel *(*channel_create)(const char *name,
- struct ltt_channel *ltt_chan,
void *buf_addr,
size_t subbuf_size, size_t num_subbuf,
unsigned int switch_timer_interval,
};
struct ltt_channel {
- unsigned int id;
+ /*
+ * The pointers located in this private data are NOT safe to be
+ * dereferenced by the consumer. The only operations the
+ * consumer process is designed to be allowed to do is to read
+ * and perform subbuffer flush.
+ */
struct channel *chan; /* Channel buffers */
int enabled;
struct lttng_ctx *ctx;
int header_type; /* 0: unset, 1: compact, 2: large */
struct lttng_ust_shm_handle *handle; /* shared-memory handle */
int metadata_dumped:1;
+
+ /* Channel ID, available for consumer too */
+ unsigned int id;
+ /* Copy of session UUID for consumer (availability through shm) */
+ uuid_t uuid; /* Trace session unique ID */
};
struct ltt_session {
int *shm_fd, int *wait_fd,
uint64_t *memory_map_size)
{
- struct ltt_channel *chan;
+ struct ltt_channel *chan = NULL;
struct ltt_transport *transport;
if (session->been_active)
transport_name);
goto notransport;
}
- chan = zmalloc(sizeof(struct ltt_channel));
- if (!chan)
- goto nomem;
- chan->session = session;
- chan->id = session->free_chan_id++;
/*
* Note: the channel creation op already writes into the packet
* headers. Therefore the "chan" information used as input
* should be already accessible.
*/
- transport->ops.channel_create("[lttng]", chan, buf_addr,
+ chan = transport->ops.channel_create("[lttng]", buf_addr,
subbuf_size, num_subbuf, switch_timer_interval,
read_timer_interval, shm_fd, wait_fd,
memory_map_size);
- if (!chan->chan)
+ if (!chan)
goto create_error;
+ chan->session = session;
+ chan->id = session->free_chan_id++;
chan->enabled = 1;
chan->ops = &transport->ops;
cds_list_add(&chan->list, &session->chan);
return chan;
create_error:
- free(chan);
-nomem:
notransport:
active:
return NULL;
static
void _ltt_channel_destroy(struct ltt_channel *chan)
{
- chan->ops->channel_destroy(chan);
cds_list_del(&chan->list);
lttng_destroy_context(chan->ctx);
- free(chan);
+ chan->ops->channel_destroy(chan);
}
/*
subbuf_idx * chan->backend.subbuf_size,
handle);
struct ltt_channel *ltt_chan = channel_get_private(chan);
- struct ltt_session *session = ltt_chan->session;
header->magic = CTF_MAGIC_NUMBER;
- memcpy(header->uuid, session->uuid, sizeof(session->uuid));
+ memcpy(header->uuid, ltt_chan->uuid, sizeof(ltt_chan->uuid));
header->stream_id = ltt_chan->id;
header->ctx.timestamp_begin = tsc;
header->ctx.timestamp_end = 0;
static
struct ltt_channel *_channel_create(const char *name,
- struct ltt_channel *ltt_chan, void *buf_addr,
+ void *buf_addr,
size_t subbuf_size, size_t num_subbuf,
unsigned int switch_timer_interval,
unsigned int read_timer_interval,
int *shm_fd, int *wait_fd,
uint64_t *memory_map_size)
{
- ltt_chan->handle = channel_create(&client_config, name, ltt_chan, buf_addr,
- subbuf_size, num_subbuf, switch_timer_interval,
- read_timer_interval, shm_fd, wait_fd,
- memory_map_size);
- if (!ltt_chan->handle)
+ void *priv;
+ struct ltt_channel *ltt_chan = NULL;
+ struct lttng_ust_shm_handle *handle;
+
+ handle = channel_create(&client_config, name,
+ &priv, __alignof__(*ltt_chan), sizeof(*ltt_chan),
+ buf_addr, subbuf_size, num_subbuf,
+ switch_timer_interval, read_timer_interval,
+ shm_fd, wait_fd, memory_map_size);
+ if (!handle)
return NULL;
+ ltt_chan = priv;
+ ltt_chan->handle = handle;
ltt_chan->chan = shmp(ltt_chan->handle, ltt_chan->handle->chan);
return ltt_chan;
}
subbuf_idx * chan->backend.subbuf_size,
handle);
struct ltt_channel *ltt_chan = channel_get_private(chan);
- struct ltt_session *session = ltt_chan->session;
header->magic = TSDL_MAGIC_NUMBER;
- memcpy(header->uuid, session->uuid, sizeof(session->uuid));
+ memcpy(header->uuid, ltt_chan->uuid, sizeof(ltt_chan->uuid));
header->checksum = 0; /* 0 if unused */
header->content_size = 0xFFFFFFFF; /* in bits, for debugging */
header->packet_size = 0xFFFFFFFF; /* in bits, for debugging */
static
struct ltt_channel *_channel_create(const char *name,
- struct ltt_channel *ltt_chan, void *buf_addr,
+ void *buf_addr,
size_t subbuf_size, size_t num_subbuf,
unsigned int switch_timer_interval,
unsigned int read_timer_interval,
int *shm_fd, int *wait_fd,
uint64_t *memory_map_size)
{
- ltt_chan->handle = channel_create(&client_config, name, ltt_chan, buf_addr,
- subbuf_size, num_subbuf, switch_timer_interval,
- read_timer_interval, shm_fd, wait_fd,
- memory_map_size);
- if (!ltt_chan->handle)
+ void *priv;
+ struct ltt_channel *ltt_chan = NULL;
+ struct lttng_ust_shm_handle *handle;
+
+ handle = channel_create(&client_config, name,
+ &priv, __alignof__(*ltt_chan), sizeof(*ltt_chan),
+ buf_addr, subbuf_size, num_subbuf,
+ switch_timer_interval, read_timer_interval,
+ shm_fd, wait_fd, memory_map_size);
+ if (!handle)
return NULL;
+ ltt_chan = priv;
+ ltt_chan->handle = handle;
ltt_chan->chan = shmp(ltt_chan->handle, ltt_chan->handle->chan);
return ltt_chan;
}
session->metadata = chan;
lttng_metadata_create_events(chan_objd);
}
-
/* The channel created holds a reference on the session */
objd_ref(session_objd);
+ /* Copy of session UUID for consumer (availability through shm) */
+ memcpy(chan->uuid, session->uuid, sizeof(session->uuid));
return chan_objd;
int channel_backend_init(struct channel_backend *chanb,
const char *name,
const struct lttng_ust_lib_ring_buffer_config *config,
- void *priv, size_t subbuf_size,
+ size_t subbuf_size,
size_t num_subbuf, struct lttng_ust_shm_handle *handle);
void channel_backend_free(struct channel_backend *chanb,
struct lttng_ust_shm_handle *handle);
int extra_reader_sb:1; /* Bool: has extra reader subbuffer */
unsigned long num_subbuf; /* Number of sub-buffers for writer */
u64 start_tsc; /* Channel creation TSC value */
- void *priv; /* Client-specific information */
+ DECLARE_SHMP(void *, priv_data);/* Client-specific information */
struct lttng_ust_lib_ring_buffer_config config; /* Ring buffer configuration */
char name[NAME_MAX]; /* Channel name */
struct lttng_ust_lib_ring_buffer_shmp buf[];
* buf_addr is a pointer the the beginning of the preallocated buffer contiguous
* address mapping. It is used only by RING_BUFFER_STATIC configuration. It can
* be set to NULL for other backends.
+ *
+ * priv_data (output) is set to a pointer into a "priv_data_len"-sized
+ * memory area for client-specific data. This memory is managed by lib
+ * ring buffer. priv_data_align is the alignment required for the
+ * private data area.
*/
extern
struct lttng_ust_shm_handle *channel_create(const struct lttng_ust_lib_ring_buffer_config *config,
- const char *name, void *priv,
+ const char *name,
+ void **priv_data,
+ size_t priv_data_align,
+ size_t priv_data_size,
void *buf_addr,
size_t subbuf_size, size_t num_subbuf,
unsigned int switch_timer_interval,
int shm_fd, int wait_fd, uint64_t memory_map_size);
/*
- * channel_destroy returns the private data pointer. It finalizes all channel's
- * buffers, waits for readers to release all references, and destroys the
- * channel.
+ * channel_destroy finalizes all channel's buffers, waits for readers to
+ * release all references, and destroys the channel.
*/
extern
-void *channel_destroy(struct channel *chan, struct lttng_ust_shm_handle *handle,
+void channel_destroy(struct channel *chan, struct lttng_ust_shm_handle *handle,
int shadow);
unsigned long read_timer_interval; /* Reader wakeup (jiffies) */
//wait_queue_head_t read_wait; /* reader wait queue */
int finalized; /* Has channel been finalized */
+ size_t priv_data_offset;
/*
* Associated backend contains a variable-length array. Needs to
* be last member.
static inline
void *channel_get_private(struct channel *chan)
{
- return chan->backend.priv;
+ return ((char *) chan) + chan->priv_data_offset;
}
/*
* @chanb: channel backend
* @name: channel name
* @config: client ring buffer configuration
- * @priv: client private data
* @parent: dentry of parent directory, %NULL for root directory
* @subbuf_size: size of sub-buffers (> PAGE_SIZE, power of 2)
* @num_subbuf: number of sub-buffers (power of 2)
int channel_backend_init(struct channel_backend *chanb,
const char *name,
const struct lttng_ust_lib_ring_buffer_config *config,
- void *priv, size_t subbuf_size, size_t num_subbuf,
+ size_t subbuf_size, size_t num_subbuf,
struct lttng_ust_shm_handle *handle)
{
struct channel *chan = caa_container_of(chanb, struct channel, backend);
if (ret)
return ret;
- chanb->priv = priv;
chanb->buf_size = num_subbuf * subbuf_size;
chanb->subbuf_size = subbuf_size;
chanb->buf_size_order = get_count_order(chanb->buf_size);
{
const struct lttng_ust_lib_ring_buffer_config *config = &chanb->config;
struct channel *chan = caa_container_of(chanb, struct channel, backend);
- void *priv = chanb->priv;
+ void *priv = channel_get_private(chan);
unsigned int num_subbuf;
size_t subbuf_header_size;
u64 tsc;
* channel_create - Create channel.
* @config: ring buffer instance configuration
* @name: name of the channel
- * @priv: ring buffer client private data
+ * @priv_data: ring buffer client private data area pointer (output)
+ * @priv_data_size: length, in bytes, of the private data area.
* @buf_addr: pointer the the beginning of the preallocated buffer contiguous
* address mapping. It is used only by RING_BUFFER_STATIC
* configuration. It can be set to NULL for other backends.
* Returns NULL on failure.
*/
struct lttng_ust_shm_handle *channel_create(const struct lttng_ust_lib_ring_buffer_config *config,
- const char *name, void *priv, void *buf_addr,
- size_t subbuf_size,
+ const char *name,
+ void **priv_data,
+ size_t priv_data_align,
+ size_t priv_data_size,
+ void *buf_addr, size_t subbuf_size,
size_t num_subbuf, unsigned int switch_timer_interval,
unsigned int read_timer_interval,
int *shm_fd, int *wait_fd, uint64_t *memory_map_size)
{
int ret, cpu;
- size_t shmsize;
+ size_t shmsize, chansize;
struct channel *chan;
struct lttng_ust_shm_handle *handle;
struct shm_object *shmobj;
shmsize += sizeof(struct lttng_ust_lib_ring_buffer_shmp) * num_possible_cpus();
else
shmsize += sizeof(struct lttng_ust_lib_ring_buffer_shmp);
+ chansize = shmsize;
+ shmsize += offset_align(shmsize, priv_data_align);
+ shmsize += priv_data_size;
shmobj = shm_object_table_append(handle->table, shmsize);
if (!shmobj)
goto error_append;
/* struct channel is at object 0, offset 0 (hardcoded) */
- set_shmp(handle->chan, zalloc_shm(shmobj, shmsize));
+ set_shmp(handle->chan, zalloc_shm(shmobj, chansize));
assert(handle->chan._ref.index == 0);
assert(handle->chan._ref.offset == 0);
chan = shmp(handle, handle->chan);
if (!chan)
goto error_append;
- ret = channel_backend_init(&chan->backend, name, config, priv,
+ /* space for private data */
+ if (priv_data_size) {
+ DECLARE_SHMP(void, priv_data_alloc);
+
+ align_shm(shmobj, priv_data_align);
+ chan->priv_data_offset = shmobj->allocated_len;
+ set_shmp(priv_data_alloc, zalloc_shm(shmobj, priv_data_size));
+ if (!shmp(handle, priv_data_alloc))
+ goto error_append;
+ *priv_data = channel_get_private(chan);
+ } else {
+ chan->priv_data_offset = -1;
+ *priv_data = NULL;
+ }
+
+ ret = channel_backend_init(&chan->backend, name, config,
subbuf_size, num_subbuf, handle);
if (ret)
goto error_backend_init;
* Call "destroy" callback, finalize channels, decrement the channel
* reference count. Note that when readers have completed data
* consumption of finalized channels, get_subbuf() will return -ENODATA.
- * They should release their handle at that point. Returns the private
- * data pointer.
+ * They should release their handle at that point.
*/
-void *channel_destroy(struct channel *chan, struct lttng_ust_shm_handle *handle,
+void channel_destroy(struct channel *chan, struct lttng_ust_shm_handle *handle,
int shadow)
{
const struct lttng_ust_lib_ring_buffer_config *config = &chan->backend.config;
- void *priv;
int cpu;
if (shadow) {
channel_release(chan, handle, shadow);
- return NULL;
+ return;
}
channel_unregister_notifiers(chan, handle);
if (config->cb.buffer_finalize)
config->cb.buffer_finalize(buf,
- chan->backend.priv,
+ channel_get_private(chan),
cpu, handle);
if (buf->backend.allocated)
lib_ring_buffer_switch_slow(buf, SWITCH_FLUSH,
struct lttng_ust_lib_ring_buffer *buf = shmp(handle, chan->backend.buf[0].shmp);
if (config->cb.buffer_finalize)
- config->cb.buffer_finalize(buf, chan->backend.priv, -1, handle);
+ config->cb.buffer_finalize(buf, channel_get_private(chan), -1, handle);
if (buf->backend.allocated)
lib_ring_buffer_switch_slow(buf, SWITCH_FLUSH,
handle);
* sessiond/consumer are keeping a reference on the shm file
* descriptor directly. No need to refcount.
*/
- priv = chan->backend.priv;
channel_release(chan, handle, shadow);
- return priv;
+ return;
}
struct lttng_ust_lib_ring_buffer *channel_get_ring_buffer(
struct lttng_ust_shm_handle *handle)
{
const struct lttng_ust_lib_ring_buffer_config *config = &chan->backend.config;
- void *priv = chan->backend.priv;
+ void *priv = channel_get_private(chan);
ERRMSG("ring buffer %s, cpu %d: %lu records written, "
"%lu records overrun\n",
projects / lttng-ust.git / commitdiff
