* Dual LGPL v2.1/GPL v2 license.
*/
+#define _GNU_SOURCE
#include <sys/types.h>
#include <sys/mman.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <urcu/compiler.h>
#include <urcu/ref.h>
+#include <helper.h>
#include "smp.h"
-#include <ust/ringbuffer-config.h>
+#include <lttng/ringbuffer-config.h>
+#include "vatomic.h"
#include "backend.h"
#include "frontend.h"
#include "shm.h"
__thread unsigned int lib_ring_buffer_nesting;
+/*
+ * TODO: this is unused. Errors are saved within the ring buffer.
+ * Eventually, allow consumerd to print these errors.
+ */
static
void lib_ring_buffer_print_errors(struct channel *chan,
struct lttng_ust_lib_ring_buffer *buf, int cpu,
- struct lttng_ust_shm_handle *handle);
-
-/*
- * Must be called under cpu hotplug protection.
- */
-void lib_ring_buffer_free(struct lttng_ust_lib_ring_buffer *buf,
- struct lttng_ust_shm_handle *handle)
-{
- struct channel *chan = shmp(handle, buf->backend.chan);
-
- lib_ring_buffer_print_errors(chan, buf, buf->backend.cpu, handle);
- /* buf->commit_hot will be freed by shm teardown */
- /* buf->commit_cold will be freed by shm teardown */
-
- lib_ring_buffer_backend_free(&buf->backend);
-}
+ struct lttng_ust_shm_handle *handle)
+ __attribute__((unused));
/**
* lib_ring_buffer_reset - Reset ring buffer to initial values.
{
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;
- unsigned int num_subbuf;
+ void *priv = channel_get_private(chan);
size_t subbuf_header_size;
- u64 tsc;
+ uint64_t tsc;
int ret;
/* Test for cpu hotplug */
goto free_commit;
}
- num_subbuf = chan->backend.num_subbuf;
- //init_waitqueue_head(&buf->read_wait);
-
/*
* Write the subbuffer header for first subbuffer so we know the total
* duration of data gathering.
free_commit:
/* commit_hot will be freed by shm teardown */
free_chanbuf:
- lib_ring_buffer_backend_free(&buf->backend);
return ret;
}
* 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.
+ * @priv_data_init: initialization data for private data.
* @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 *priv_data_init,
+ 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 **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;
/* Calculate the shm allocation layout */
shmsize = sizeof(struct channel);
+ shmsize += offset_align(shmsize, __alignof__(struct lttng_ust_lib_ring_buffer_shmp));
if (config->alloc == RING_BUFFER_ALLOC_PER_CPU)
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, sizeof(struct channel)));
+ 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);
+ memcpy(*priv_data, priv_data_init, priv_data_size);
+ } 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->alloc == RING_BUFFER_ALLOC_PER_CPU) {
- for_each_channel_cpu(cpu, chan) {
- struct lttng_ust_lib_ring_buffer *buf = shmp(handle, chan->backend.buf[cpu].shmp);
-
- if (config->cb.buffer_finalize)
- config->cb.buffer_finalize(buf,
- chan->backend.priv,
- cpu, handle);
- if (buf->backend.allocated)
- lib_ring_buffer_switch_slow(buf, SWITCH_FLUSH,
- handle);
- /*
- * Perform flush before writing to finalized.
- */
- cmm_smp_wmb();
- CMM_ACCESS_ONCE(buf->finalized) = 1;
- //wake_up_interruptible(&buf->read_wait);
- }
- } else {
- struct lttng_ust_lib_ring_buffer *buf = shmp(handle, chan->backend.buf[0].shmp);
+ /*
+ * Note: the consumer takes care of finalizing and switching the
+ * buffers.
+ */
- if (config->cb.buffer_finalize)
- config->cb.buffer_finalize(buf, chan->backend.priv, -1, handle);
- if (buf->backend.allocated)
- lib_ring_buffer_switch_slow(buf, SWITCH_FLUSH,
- handle);
- /*
- * Perform flush before writing to finalized.
- */
- cmm_smp_wmb();
- CMM_ACCESS_ONCE(buf->finalized) = 1;
- //wake_up_interruptible(&buf->read_wait);
- }
- CMM_ACCESS_ONCE(chan->finalized) = 1;
- //wake_up_interruptible(&chan->hp_wait);
- //wake_up_interruptible(&chan->read_wait);
/*
* 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(
const struct lttng_ust_lib_ring_buffer_config *config,
struct channel *chan, int cpu,
struct lttng_ust_shm_handle *handle,
- int *shm_fd, int *wait_fd,
- uint64_t *memory_map_size)
+ int **shm_fd, int **wait_fd,
+ uint64_t **memory_map_size)
{
struct shm_ref *ref;
commit_count_sb = v_read(config, &shmp_index(handle, buf->commit_cold, cons_idx)->cc_sb);
if (subbuf_offset(commit_count, chan) != 0)
- ERRMSG("ring buffer %s, cpu %d: "
+ DBG("ring buffer %s, cpu %d: "
"commit count in subbuffer %lu,\n"
"expecting multiples of %lu bytes\n"
" [ %lu bytes committed, %lu bytes reader-visible ]\n",
chan->backend.subbuf_size,
commit_count, commit_count_sb);
- ERRMSG("ring buffer: %s, cpu %d: %lu bytes committed\n",
+ DBG("ring buffer: %s, cpu %d: %lu bytes committed\n",
chan->backend.name, cpu, commit_count);
}
const struct lttng_ust_lib_ring_buffer_config *config = &chan->backend.config;
unsigned long write_offset, cons_offset;
- /*
- * Can be called in the error path of allocation when
- * trans_channel_data is not yet set.
- */
- if (!chan)
- return;
/*
* No need to order commit_count, write_offset and cons_offset reads
* because we execute at teardown when no more writer nor reader
write_offset = v_read(config, &buf->offset);
cons_offset = uatomic_read(&buf->consumed);
if (write_offset != cons_offset)
- ERRMSG("ring buffer %s, cpu %d: "
+ DBG("ring buffer %s, cpu %d: "
"non-consumed data\n"
" [ %lu bytes written, %lu bytes read ]\n",
chan->backend.name, cpu, write_offset, cons_offset);
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, "
+ DBG("ring buffer %s, cpu %d: %lu records written, "
"%lu records overrun\n",
chan->backend.name, cpu,
v_read(config, &buf->records_count),
if (v_read(config, &buf->records_lost_full)
|| v_read(config, &buf->records_lost_wrap)
|| v_read(config, &buf->records_lost_big))
- ERRMSG("ring buffer %s, cpu %d: records were lost. Caused by:\n"
+ DBG("ring buffer %s, cpu %d: records were lost. Caused by:\n"
" [ %lu buffer full, %lu nest buffer wrap-around, "
"%lu event too big ]\n",
chan->backend.name, cpu,
void lib_ring_buffer_switch_old_start(struct lttng_ust_lib_ring_buffer *buf,
struct channel *chan,
struct switch_offsets *offsets,
- u64 tsc,
+ uint64_t tsc,
struct lttng_ust_shm_handle *handle)
{
const struct lttng_ust_lib_ring_buffer_config *config = &chan->backend.config;
void lib_ring_buffer_switch_old_end(struct lttng_ust_lib_ring_buffer *buf,
struct channel *chan,
struct switch_offsets *offsets,
- u64 tsc,
+ uint64_t tsc,
struct lttng_ust_shm_handle *handle)
{
const struct lttng_ust_lib_ring_buffer_config *config = &chan->backend.config;
void lib_ring_buffer_switch_new_start(struct lttng_ust_lib_ring_buffer *buf,
struct channel *chan,
struct switch_offsets *offsets,
- u64 tsc,
+ uint64_t tsc,
struct lttng_ust_shm_handle *handle)
{
const struct lttng_ust_lib_ring_buffer_config *config = &chan->backend.config;
void lib_ring_buffer_switch_new_end(struct lttng_ust_lib_ring_buffer *buf,
struct channel *chan,
struct switch_offsets *offsets,
- u64 tsc,
+ uint64_t tsc,
struct lttng_ust_shm_handle *handle)
{
const struct lttng_ust_lib_ring_buffer_config *config = &chan->backend.config;
struct lttng_ust_lib_ring_buffer *buf,
struct channel *chan,
struct switch_offsets *offsets,
- u64 *tsc)
+ uint64_t *tsc)
{
const struct lttng_ust_lib_ring_buffer_config *config = &chan->backend.config;
unsigned long off;
* quiescence guarantees for the fusion merge.
*/
if (mode == SWITCH_FLUSH || off > 0) {
- if (unlikely(off == 0)) {
+ if (caa_unlikely(off == 0)) {
/*
* The client does not save any header information.
* Don't switch empty subbuffer on finalize, because it
const struct lttng_ust_lib_ring_buffer_config *config = &chan->backend.config;
struct switch_offsets offsets;
unsigned long oldidx;
- u64 tsc;
+ uint64_t tsc;
offsets.size = 0;
if (last_tsc_overflow(config, buf, ctx->tsc))
ctx->rflags |= RING_BUFFER_RFLAG_FULL_TSC;
- if (unlikely(subbuf_offset(offsets->begin, ctx->chan) == 0)) {
+ if (caa_unlikely(subbuf_offset(offsets->begin, ctx->chan) == 0)) {
offsets->switch_new_start = 1; /* For offsets->begin */
} else {
offsets->size = config->cb.record_header_size(config, chan,
lib_ring_buffer_align(offsets->begin + offsets->size,
ctx->largest_align)
+ ctx->data_size;
- if (unlikely(subbuf_offset(offsets->begin, chan) +
+ if (caa_unlikely(subbuf_offset(offsets->begin, chan) +
offsets->size > chan->backend.subbuf_size)) {
offsets->switch_old_end = 1; /* For offsets->old */
offsets->switch_new_start = 1; /* For offsets->begin */
}
}
- if (unlikely(offsets->switch_new_start)) {
+ if (caa_unlikely(offsets->switch_new_start)) {
unsigned long sb_index;
/*
* We are typically not filling the previous buffer completely.
*/
- if (likely(offsets->switch_old_end))
+ if (caa_likely(offsets->switch_old_end))
offsets->begin = subbuf_align(offsets->begin, chan);
offsets->begin = offsets->begin
+ config->cb.subbuffer_header_size();
- ((unsigned long) v_read(config,
&shmp_index(handle, buf->commit_cold, sb_index)->cc_sb)
& chan->commit_count_mask);
- if (likely(reserve_commit_diff == 0)) {
+ if (caa_likely(reserve_commit_diff == 0)) {
/* Next subbuffer not being written to. */
- if (unlikely(config->mode != RING_BUFFER_OVERWRITE &&
+ if (caa_unlikely(config->mode != RING_BUFFER_OVERWRITE &&
subbuf_trunc(offsets->begin, chan)
- subbuf_trunc((unsigned long)
uatomic_read(&buf->consumed), chan)
lib_ring_buffer_align(offsets->begin + offsets->size,
ctx->largest_align)
+ ctx->data_size;
- if (unlikely(subbuf_offset(offsets->begin, chan)
+ if (caa_unlikely(subbuf_offset(offsets->begin, chan)
+ offsets->size > chan->backend.subbuf_size)) {
/*
* Record too big for subbuffers, report error, don't
}
offsets->end = offsets->begin + offsets->size;
- if (unlikely(subbuf_offset(offsets->end, chan) == 0)) {
+ if (caa_unlikely(subbuf_offset(offsets->end, chan) == 0)) {
/*
* The offset_end will fall at the very beginning of the next
* subbuffer.
do {
ret = lib_ring_buffer_try_reserve_slow(buf, chan, &offsets,
ctx);
- if (unlikely(ret))
+ if (caa_unlikely(ret))
return ret;
- } while (unlikely(v_cmpxchg(config, &buf->offset, offsets.old,
+ } while (caa_unlikely(v_cmpxchg(config, &buf->offset, offsets.old,
offsets.end)
!= offsets.old));
/*
* Switch old subbuffer if needed.
*/
- if (unlikely(offsets.switch_old_end)) {
+ if (caa_unlikely(offsets.switch_old_end)) {
lib_ring_buffer_clear_noref(config, &buf->backend,
subbuf_index(offsets.old - 1, chan),
handle);
/*
* Populate new subbuffer.
*/
- if (unlikely(offsets.switch_new_start))
+ if (caa_unlikely(offsets.switch_new_start))
lib_ring_buffer_switch_new_start(buf, chan, &offsets, ctx->tsc, handle);
- if (unlikely(offsets.switch_new_end))
+ if (caa_unlikely(offsets.switch_new_end))
lib_ring_buffer_switch_new_end(buf, chan, &offsets, ctx->tsc, handle);
ctx->slot_size = offsets.size;