/*
* lttng-ring-buffer-client.h
*
* LTTng lib ring buffer client template.
*
* Copyright (C) 2010-2012 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; only
* version 2.1 of the License.
*
* This library 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
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include <stdint.h>
#include <lttng/ust-events.h>
#include "lttng/bitfield.h"
#include "lttng-tracer.h"
#include "../libringbuffer/frontend_types.h"
struct metadata_packet_header {
uint32_t magic; /* 0x75D11D57 */
uint8_t uuid[LTTNG_UST_UUID_LEN]; /* Unique Universal Identifier */
uint32_t checksum; /* 0 if unused */
uint32_t content_size; /* in bits */
uint32_t packet_size; /* in bits */
uint8_t compression_scheme; /* 0 if unused */
uint8_t encryption_scheme; /* 0 if unused */
uint8_t checksum_scheme; /* 0 if unused */
uint8_t major; /* CTF spec major version number */
uint8_t minor; /* CTF spec minor version number */
uint8_t header_end[0];
};
struct metadata_record_header {
uint8_t header_end[0]; /* End of header */
};
static const struct lttng_ust_lib_ring_buffer_config client_config;
static inline uint64_t lib_ring_buffer_clock_read(struct channel *chan)
{
return 0;
}
static inline
size_t record_header_size(const struct lttng_ust_lib_ring_buffer_config *config,
struct channel *chan, size_t offset,
size_t *pre_header_padding,
struct lttng_ust_lib_ring_buffer_ctx *ctx,
void *client_ctx)
{
return 0;
}
#include "../libringbuffer/api.h"
#include "lttng-rb-clients.h"
static uint64_t client_ring_buffer_clock_read(struct channel *chan)
{
return 0;
}
static
size_t client_record_header_size(const struct lttng_ust_lib_ring_buffer_config *config,
struct channel *chan, size_t offset,
size_t *pre_header_padding,
struct lttng_ust_lib_ring_buffer_ctx *ctx,
void *client_ctx)
{
return 0;
}
/**
* client_packet_header_size - called on buffer-switch to a new sub-buffer
*
* Return header size without padding after the structure. Don't use packed
* structure because gcc generates inefficient code on some architectures
* (powerpc, mips..)
*/
static size_t client_packet_header_size(void)
{
return offsetof(struct metadata_packet_header, header_end);
}
static void client_buffer_begin(struct lttng_ust_lib_ring_buffer *buf, uint64_t tsc,
unsigned int subbuf_idx,
struct lttng_ust_shm_handle *handle)
{
struct channel *chan = shmp(handle, buf->backend.chan);
struct metadata_packet_header *header =
(struct metadata_packet_header *)
lib_ring_buffer_offset_address(&buf->backend,
subbuf_idx * chan->backend.subbuf_size,
handle);
struct lttng_channel *lttng_chan = channel_get_private(chan);
assert(header);
if (!header)
return;
header->magic = TSDL_MAGIC_NUMBER;
memcpy(header->uuid, lttng_chan->uuid, sizeof(lttng_chan->uuid));
header->checksum = 0; /* 0 if unused */
header->content_size = 0xFFFFFFFF; /* in bits, for debugging */
header->packet_size = 0xFFFFFFFF; /* in bits, for debugging */
header->compression_scheme = 0; /* 0 if unused */
header->encryption_scheme = 0; /* 0 if unused */
header->checksum_scheme = 0; /* 0 if unused */
header->major = CTF_SPEC_MAJOR;
header->minor = CTF_SPEC_MINOR;
}
/*
* offset is assumed to never be 0 here : never deliver a completely empty
* subbuffer. data_size is between 1 and subbuf_size.
*/
static void client_buffer_end(struct lttng_ust_lib_ring_buffer *buf, uint64_t tsc,
unsigned int subbuf_idx, unsigned long data_size,
struct lttng_ust_shm_handle *handle)
{
struct channel *chan = shmp(handle, buf->backend.chan);
struct metadata_packet_header *header =
(struct metadata_packet_header *)
lib_ring_buffer_offset_address(&buf->backend,
subbuf_idx * chan->backend.subbuf_size,
handle);
unsigned long records_lost = 0;
assert(header);
if (!header)
return;
header->content_size = data_size * CHAR_BIT; /* in bits */
header->packet_size = PAGE_ALIGN(data_size) * CHAR_BIT; /* in bits */
/*
* We do not care about the records lost count, because the metadata
* channel waits and retry.
*/
(void) lib_ring_buffer_get_records_lost_full(&client_config, buf);
records_lost += lib_ring_buffer_get_records_lost_wrap(&client_config, buf);
records_lost += lib_ring_buffer_get_records_lost_big(&client_config, buf);
WARN_ON_ONCE(records_lost != 0);
}
static int client_buffer_create(struct lttng_ust_lib_ring_buffer *buf, void *priv,
int cpu, const char *name,
struct lttng_ust_shm_handle *handle)
{
return 0;
}
static void client_buffer_finalize(struct lttng_ust_lib_ring_buffer *buf,
void *priv, int cpu,
struct lttng_ust_shm_handle *handle)
{
}
static const
struct lttng_ust_client_lib_ring_buffer_client_cb client_cb = {
.parent = {
.ring_buffer_clock_read = client_ring_buffer_clock_read,
.record_header_size = client_record_header_size,
.subbuffer_header_size = client_packet_header_size,
.buffer_begin = client_buffer_begin,
.buffer_end = client_buffer_end,
.buffer_create = client_buffer_create,
.buffer_finalize = client_buffer_finalize,
},
};
static const struct lttng_ust_lib_ring_buffer_config client_config = {
.cb.ring_buffer_clock_read = client_ring_buffer_clock_read,
.cb.record_header_size = client_record_header_size,
.cb.subbuffer_header_size = client_packet_header_size,
.cb.buffer_begin = client_buffer_begin,
.cb.buffer_end = client_buffer_end,
.cb.buffer_create = client_buffer_create,
.cb.buffer_finalize = client_buffer_finalize,
.tsc_bits = 0,
.alloc = RING_BUFFER_ALLOC_GLOBAL,
.sync = RING_BUFFER_SYNC_GLOBAL,
.mode = RING_BUFFER_MODE_TEMPLATE,
.backend = RING_BUFFER_PAGE,
.output = RING_BUFFER_MMAP,
.oops = RING_BUFFER_OOPS_CONSISTENCY,
.ipi = RING_BUFFER_NO_IPI_BARRIER,
.wakeup = RING_BUFFER_WAKEUP_BY_WRITER,
.client_type = LTTNG_CLIENT_TYPE,
.cb_ptr = &client_cb.parent,
};
const struct lttng_ust_client_lib_ring_buffer_client_cb *LTTNG_CLIENT_CALLBACKS = &client_cb;
static
struct lttng_channel *_channel_create(const char *name,
void *buf_addr,
size_t subbuf_size, size_t num_subbuf,
unsigned int switch_timer_interval,
unsigned int read_timer_interval,
unsigned char *uuid,
uint32_t chan_id,
const int *stream_fds, int nr_stream_fds,
int64_t blocking_timeout)
{
struct lttng_channel chan_priv_init;
struct lttng_ust_shm_handle *handle;
struct lttng_channel *lttng_chan;
void *priv;
memset(&chan_priv_init, 0, sizeof(chan_priv_init));
memcpy(chan_priv_init.uuid, uuid, LTTNG_UST_UUID_LEN);
chan_priv_init.id = chan_id;
handle = channel_create(&client_config, name,
&priv, __alignof__(struct lttng_channel),
sizeof(struct lttng_channel),
&chan_priv_init,
buf_addr, subbuf_size, num_subbuf,
switch_timer_interval, read_timer_interval,
stream_fds, nr_stream_fds, blocking_timeout);
if (!handle)
return NULL;
lttng_chan = priv;
lttng_chan->handle = handle;
lttng_chan->chan = shmp(handle, handle->chan);
return lttng_chan;
}
static
void lttng_channel_destroy(struct lttng_channel *chan)
{
channel_destroy(chan->chan, chan->handle, 1);
}
static
int lttng_event_reserve(struct lttng_ust_lib_ring_buffer_ctx *ctx, uint32_t event_id)
{
int ret;
ret = lib_ring_buffer_reserve(&client_config, ctx, NULL);
if (ret)
return ret;
if (caa_likely(ctx->ctx_len
>= sizeof(struct lttng_ust_lib_ring_buffer_ctx))) {
if (lib_ring_buffer_backend_get_pages(&client_config, ctx,
&ctx->backend_pages))
return -EPERM;
}
return 0;
}
static
void lttng_event_commit(struct lttng_ust_lib_ring_buffer_ctx *ctx)
{
lib_ring_buffer_commit(&client_config, ctx);
}
static
void lttng_event_write(struct lttng_ust_lib_ring_buffer_ctx *ctx, const void *src,
size_t len)
{
lib_ring_buffer_write(&client_config, ctx, src, len);
}
static
size_t lttng_packet_avail_size(struct channel *chan, struct lttng_ust_shm_handle *handle)
{
unsigned long o_begin;
struct lttng_ust_lib_ring_buffer *buf;
buf = shmp(handle, chan->backend.buf[0].shmp); /* Only for global buffer ! */
o_begin = v_read(&client_config, &buf->offset);
if (subbuf_offset(o_begin, chan) != 0) {
return chan->backend.subbuf_size - subbuf_offset(o_begin, chan);
} else {
return chan->backend.subbuf_size - subbuf_offset(o_begin, chan)
- sizeof(struct metadata_packet_header);
}
}
#if 0
static
wait_queue_head_t *lttng_get_reader_wait_queue(struct channel *chan)
{
return &chan->read_wait;
}
static
wait_queue_head_t *lttng_get_hp_wait_queue(struct channel *chan)
{
return &chan->hp_wait;
}
#endif //0
static
int lttng_is_finalized(struct channel *chan)
{
return lib_ring_buffer_channel_is_finalized(chan);
}
static
int lttng_is_disabled(struct channel *chan)
{
return lib_ring_buffer_channel_is_disabled(chan);
}
static
int lttng_flush_buffer(struct channel *chan, struct lttng_ust_shm_handle *handle)
{
struct lttng_ust_lib_ring_buffer *buf;
int shm_fd, wait_fd, wakeup_fd;
uint64_t memory_map_size;
buf = channel_get_ring_buffer(&client_config, chan,
0, handle, &shm_fd, &wait_fd, &wakeup_fd,
&memory_map_size);
lib_ring_buffer_switch(&client_config, buf,
SWITCH_ACTIVE, handle);
return 0;
}
static struct lttng_transport lttng_relay_transport = {
.name = "relay-" RING_BUFFER_MODE_TEMPLATE_STRING "-mmap",
.ops = {
.channel_create = _channel_create,
.channel_destroy = lttng_channel_destroy,
.event_reserve = lttng_event_reserve,
.event_commit = lttng_event_commit,
.event_write = lttng_event_write,
.packet_avail_size = lttng_packet_avail_size,
//.get_reader_wait_queue = lttng_get_reader_wait_queue,
//.get_hp_wait_queue = lttng_get_hp_wait_queue,
.is_finalized = lttng_is_finalized,
.is_disabled = lttng_is_disabled,
.flush_buffer = lttng_flush_buffer,
},
.client_config = &client_config,
};
void RING_BUFFER_MODE_TEMPLATE_INIT(void)
{
DBG("LTT : ltt ring buffer client \"%s\" init\n",
"relay-" RING_BUFFER_MODE_TEMPLATE_STRING "-mmap");
lttng_transport_register(<tng_relay_transport);
}
void RING_BUFFER_MODE_TEMPLATE_EXIT(void)
{
DBG("LTT : ltt ring buffer client \"%s\" exit\n",
"relay-" RING_BUFFER_MODE_TEMPLATE_STRING "-mmap");
lttng_transport_unregister(<tng_relay_transport);
}