+++ /dev/null
-/*
- * SPDX-License-Identifier: LGPL-2.1-only
- *
- * Copyright (C) 2010-2012 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
- *
- * LTTng lib ring buffer client template.
- */
-
-#include <stddef.h>
-#include <stdint.h>
-#include <lttng/ust-events.h>
-#include "ust-bitfield.h"
-#include "ust-compat.h"
-#include "clock.h"
-#include "lttng-tracer.h"
-#include "../libringbuffer/frontend_types.h"
-
-#define LTTNG_COMPACT_EVENT_BITS 5
-#define LTTNG_COMPACT_TSC_BITS 27
-
-enum app_ctx_mode {
- APP_CTX_DISABLED,
- APP_CTX_ENABLED,
-};
-
-/*
- * Keep the natural field alignment for _each field_ within this structure if
- * you ever add/remove a field from this header. Packed attribute is not used
- * because gcc generates poor code on at least powerpc and mips. Don't ever
- * let gcc add padding between the structure elements.
- */
-
-struct packet_header {
- /* Trace packet header */
- uint32_t magic; /*
- * Trace magic number.
- * contains endianness information.
- */
- uint8_t uuid[LTTNG_UST_UUID_LEN];
- uint32_t stream_id;
- uint64_t stream_instance_id;
-
- struct {
- /* Stream packet context */
- uint64_t timestamp_begin; /* Cycle count at subbuffer start */
- uint64_t timestamp_end; /* Cycle count at subbuffer end */
- uint64_t content_size; /* Size of data in subbuffer */
- uint64_t packet_size; /* Subbuffer size (include padding) */
- uint64_t packet_seq_num; /* Packet sequence number */
- unsigned long events_discarded; /*
- * Events lost in this subbuffer since
- * the beginning of the trace.
- * (may overflow)
- */
- uint32_t cpu_id; /* CPU id associated with stream */
- uint8_t header_end; /* End of header */
- } ctx;
-};
-
-struct lttng_client_ctx {
- size_t packet_context_len;
- size_t event_context_len;
-};
-
-static inline uint64_t lib_ring_buffer_clock_read(struct channel *chan)
-{
- return trace_clock_read64();
-}
-
-static inline
-size_t ctx_get_aligned_size(size_t offset, struct lttng_ctx *ctx,
- size_t ctx_len)
-{
- size_t orig_offset = offset;
-
- if (caa_likely(!ctx))
- return 0;
- offset += lib_ring_buffer_align(offset, ctx->largest_align);
- offset += ctx_len;
- return offset - orig_offset;
-}
-
-static inline
-void ctx_get_struct_size(struct lttng_ctx *ctx, size_t *ctx_len,
- enum app_ctx_mode mode)
-{
- int i;
- size_t offset = 0;
-
- if (caa_likely(!ctx)) {
- *ctx_len = 0;
- return;
- }
- for (i = 0; i < ctx->nr_fields; i++) {
- if (mode == APP_CTX_ENABLED) {
- offset += ctx->fields[i].get_size(&ctx->fields[i], offset);
- } else {
- if (lttng_context_is_app(ctx->fields[i].event_field.name)) {
- /*
- * Before UST 2.8, we cannot use the
- * application context, because we
- * cannot trust that the handler used
- * for get_size is the same used for
- * ctx_record, which would result in
- * corrupted traces when tracing
- * concurrently with application context
- * register/unregister.
- */
- offset += lttng_ust_dummy_get_size(&ctx->fields[i], offset);
- } else {
- offset += ctx->fields[i].get_size(&ctx->fields[i], offset);
- }
- }
- }
- *ctx_len = offset;
-}
-
-static inline
-void ctx_record(struct lttng_ust_lib_ring_buffer_ctx *bufctx,
- struct lttng_channel *chan,
- struct lttng_ctx *ctx,
- enum app_ctx_mode mode)
-{
- int i;
-
- if (caa_likely(!ctx))
- return;
- lib_ring_buffer_align_ctx(bufctx, ctx->largest_align);
- for (i = 0; i < ctx->nr_fields; i++) {
- if (mode == APP_CTX_ENABLED) {
- ctx->fields[i].record(&ctx->fields[i], bufctx, chan);
- } else {
- if (lttng_context_is_app(ctx->fields[i].event_field.name)) {
- /*
- * Before UST 2.8, we cannot use the
- * application context, because we
- * cannot trust that the handler used
- * for get_size is the same used for
- * ctx_record, which would result in
- * corrupted traces when tracing
- * concurrently with application context
- * register/unregister.
- */
- lttng_ust_dummy_record(&ctx->fields[i], bufctx, chan);
- } else {
- ctx->fields[i].record(&ctx->fields[i], bufctx, chan);
- }
- }
- }
-}
-
-/*
- * record_header_size - Calculate the header size and padding necessary.
- * @config: ring buffer instance configuration
- * @chan: channel
- * @offset: offset in the write buffer
- * @pre_header_padding: padding to add before the header (output)
- * @ctx: reservation context
- *
- * Returns the event header size (including padding).
- *
- * The payload must itself determine its own alignment from the biggest type it
- * contains.
- */
-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,
- struct lttng_client_ctx *client_ctx)
-{
- struct lttng_channel *lttng_chan = channel_get_private(chan);
- struct lttng_event *event = ctx->priv;
- struct lttng_stack_ctx *lttng_ctx = ctx->priv2;
- size_t orig_offset = offset;
- size_t padding;
-
- switch (lttng_chan->header_type) {
- case 1: /* compact */
- padding = lib_ring_buffer_align(offset, lttng_alignof(uint32_t));
- offset += padding;
- if (!(ctx->rflags & (RING_BUFFER_RFLAG_FULL_TSC | LTTNG_RFLAG_EXTENDED))) {
- offset += sizeof(uint32_t); /* id and timestamp */
- } else {
- /* Minimum space taken by LTTNG_COMPACT_EVENT_BITS id */
- offset += (LTTNG_COMPACT_EVENT_BITS + CHAR_BIT - 1) / CHAR_BIT;
- /* Align extended struct on largest member */
- offset += lib_ring_buffer_align(offset, lttng_alignof(uint64_t));
- offset += sizeof(uint32_t); /* id */
- offset += lib_ring_buffer_align(offset, lttng_alignof(uint64_t));
- offset += sizeof(uint64_t); /* timestamp */
- }
- break;
- case 2: /* large */
- padding = lib_ring_buffer_align(offset, lttng_alignof(uint16_t));
- offset += padding;
- offset += sizeof(uint16_t);
- if (!(ctx->rflags & (RING_BUFFER_RFLAG_FULL_TSC | LTTNG_RFLAG_EXTENDED))) {
- offset += lib_ring_buffer_align(offset, lttng_alignof(uint32_t));
- offset += sizeof(uint32_t); /* timestamp */
- } else {
- /* Align extended struct on largest member */
- offset += lib_ring_buffer_align(offset, lttng_alignof(uint64_t));
- offset += sizeof(uint32_t); /* id */
- offset += lib_ring_buffer_align(offset, lttng_alignof(uint64_t));
- offset += sizeof(uint64_t); /* timestamp */
- }
- break;
- default:
- padding = 0;
- WARN_ON_ONCE(1);
- }
- if (lttng_ctx) {
- /* 2.8+ probe ABI. */
- offset += ctx_get_aligned_size(offset, lttng_ctx->chan_ctx,
- client_ctx->packet_context_len);
- offset += ctx_get_aligned_size(offset, lttng_ctx->event_ctx,
- client_ctx->event_context_len);
- } else {
- /* Pre 2.8 probe ABI. */
- offset += ctx_get_aligned_size(offset, lttng_chan->ctx,
- client_ctx->packet_context_len);
- offset += ctx_get_aligned_size(offset, event->ctx,
- client_ctx->event_context_len);
- }
- *pre_header_padding = padding;
- return offset - orig_offset;
-}
-
-#include "../libringbuffer/api.h"
-#include "lttng-rb-clients.h"
-
-static
-void lttng_write_event_header_slow(const struct lttng_ust_lib_ring_buffer_config *config,
- struct lttng_ust_lib_ring_buffer_ctx *ctx,
- uint32_t event_id);
-
-/*
- * lttng_write_event_header
- *
- * Writes the event header to the offset (already aligned on 32-bits).
- *
- * @config: ring buffer instance configuration
- * @ctx: reservation context
- * @event_id: event ID
- */
-static __inline__
-void lttng_write_event_header(const struct lttng_ust_lib_ring_buffer_config *config,
- struct lttng_ust_lib_ring_buffer_ctx *ctx,
- uint32_t event_id)
-{
- struct lttng_channel *lttng_chan = channel_get_private(ctx->chan);
- struct lttng_event *event = ctx->priv;
- struct lttng_stack_ctx *lttng_ctx = ctx->priv2;
-
- if (caa_unlikely(ctx->rflags))
- goto slow_path;
-
- switch (lttng_chan->header_type) {
- case 1: /* compact */
- {
- uint32_t id_time = 0;
-
- bt_bitfield_write(&id_time, uint32_t,
- 0,
- LTTNG_COMPACT_EVENT_BITS,
- event_id);
- bt_bitfield_write(&id_time, uint32_t,
- LTTNG_COMPACT_EVENT_BITS,
- LTTNG_COMPACT_TSC_BITS,
- ctx->tsc);
- lib_ring_buffer_write(config, ctx, &id_time, sizeof(id_time));
- break;
- }
- case 2: /* large */
- {
- uint32_t timestamp = (uint32_t) ctx->tsc;
- uint16_t id = event_id;
-
- lib_ring_buffer_write(config, ctx, &id, sizeof(id));
- lib_ring_buffer_align_ctx(ctx, lttng_alignof(uint32_t));
- lib_ring_buffer_write(config, ctx, ×tamp, sizeof(timestamp));
- break;
- }
- default:
- WARN_ON_ONCE(1);
- }
-
- if (lttng_ctx) {
- /* 2.8+ probe ABI. */
- ctx_record(ctx, lttng_chan, lttng_ctx->chan_ctx, APP_CTX_ENABLED);
- ctx_record(ctx, lttng_chan, lttng_ctx->event_ctx, APP_CTX_ENABLED);
- } else {
- /* Pre 2.8 probe ABI. */
- ctx_record(ctx, lttng_chan, lttng_chan->ctx, APP_CTX_DISABLED);
- ctx_record(ctx, lttng_chan, event->ctx, APP_CTX_DISABLED);
- }
- lib_ring_buffer_align_ctx(ctx, ctx->largest_align);
-
- return;
-
-slow_path:
- lttng_write_event_header_slow(config, ctx, event_id);
-}
-
-static
-void lttng_write_event_header_slow(const struct lttng_ust_lib_ring_buffer_config *config,
- struct lttng_ust_lib_ring_buffer_ctx *ctx,
- uint32_t event_id)
-{
- struct lttng_channel *lttng_chan = channel_get_private(ctx->chan);
- struct lttng_event *event = ctx->priv;
- struct lttng_stack_ctx *lttng_ctx = ctx->priv2;
-
- switch (lttng_chan->header_type) {
- case 1: /* compact */
- if (!(ctx->rflags & (RING_BUFFER_RFLAG_FULL_TSC | LTTNG_RFLAG_EXTENDED))) {
- uint32_t id_time = 0;
-
- bt_bitfield_write(&id_time, uint32_t,
- 0,
- LTTNG_COMPACT_EVENT_BITS,
- event_id);
- bt_bitfield_write(&id_time, uint32_t,
- LTTNG_COMPACT_EVENT_BITS,
- LTTNG_COMPACT_TSC_BITS,
- ctx->tsc);
- lib_ring_buffer_write(config, ctx, &id_time, sizeof(id_time));
- } else {
- uint8_t id = 0;
- uint64_t timestamp = ctx->tsc;
-
- bt_bitfield_write(&id, uint8_t,
- 0,
- LTTNG_COMPACT_EVENT_BITS,
- 31);
- lib_ring_buffer_write(config, ctx, &id, sizeof(id));
- /* Align extended struct on largest member */
- lib_ring_buffer_align_ctx(ctx, lttng_alignof(uint64_t));
- lib_ring_buffer_write(config, ctx, &event_id, sizeof(event_id));
- lib_ring_buffer_align_ctx(ctx, lttng_alignof(uint64_t));
- lib_ring_buffer_write(config, ctx, ×tamp, sizeof(timestamp));
- }
- break;
- case 2: /* large */
- {
- if (!(ctx->rflags & (RING_BUFFER_RFLAG_FULL_TSC | LTTNG_RFLAG_EXTENDED))) {
- uint32_t timestamp = (uint32_t) ctx->tsc;
- uint16_t id = event_id;
-
- lib_ring_buffer_write(config, ctx, &id, sizeof(id));
- lib_ring_buffer_align_ctx(ctx, lttng_alignof(uint32_t));
- lib_ring_buffer_write(config, ctx, ×tamp, sizeof(timestamp));
- } else {
- uint16_t id = 65535;
- uint64_t timestamp = ctx->tsc;
-
- lib_ring_buffer_write(config, ctx, &id, sizeof(id));
- /* Align extended struct on largest member */
- lib_ring_buffer_align_ctx(ctx, lttng_alignof(uint64_t));
- lib_ring_buffer_write(config, ctx, &event_id, sizeof(event_id));
- lib_ring_buffer_align_ctx(ctx, lttng_alignof(uint64_t));
- lib_ring_buffer_write(config, ctx, ×tamp, sizeof(timestamp));
- }
- break;
- }
- default:
- WARN_ON_ONCE(1);
- }
- if (lttng_ctx) {
- /* 2.8+ probe ABI. */
- ctx_record(ctx, lttng_chan, lttng_ctx->chan_ctx, APP_CTX_ENABLED);
- ctx_record(ctx, lttng_chan, lttng_ctx->event_ctx, APP_CTX_ENABLED);
- } else {
- /* Pre 2.8 probe ABI. */
- ctx_record(ctx, lttng_chan, lttng_chan->ctx, APP_CTX_DISABLED);
- ctx_record(ctx, lttng_chan, event->ctx, APP_CTX_DISABLED);
- }
- lib_ring_buffer_align_ctx(ctx, ctx->largest_align);
-}
-
-static const struct lttng_ust_lib_ring_buffer_config client_config;
-
-static uint64_t client_ring_buffer_clock_read(struct channel *chan)
-{
- return lib_ring_buffer_clock_read(chan);
-}
-
-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 record_header_size(config, chan, offset,
- pre_header_padding, ctx, client_ctx);
-}
-
-/**
- * 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 packet_header, ctx.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 packet_header *header =
- (struct 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);
- uint64_t cnt = shmp_index(handle, buf->backend.buf_cnt, subbuf_idx)->seq_cnt;
-
- assert(header);
- if (!header)
- return;
- header->magic = CTF_MAGIC_NUMBER;
- memcpy(header->uuid, lttng_chan->uuid, sizeof(lttng_chan->uuid));
- header->stream_id = lttng_chan->id;
- header->stream_instance_id = buf->backend.cpu;
- header->ctx.timestamp_begin = tsc;
- header->ctx.timestamp_end = 0;
- header->ctx.content_size = ~0ULL; /* for debugging */
- header->ctx.packet_size = ~0ULL;
- header->ctx.packet_seq_num = chan->backend.num_subbuf * cnt + subbuf_idx;
- header->ctx.events_discarded = 0;
- header->ctx.cpu_id = buf->backend.cpu;
-}
-
-/*
- * 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 packet_header *header =
- (struct 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->ctx.timestamp_end = tsc;
- header->ctx.content_size =
- (uint64_t) data_size * CHAR_BIT; /* in bits */
- header->ctx.packet_size =
- (uint64_t) LTTNG_UST_PAGE_ALIGN(data_size) * CHAR_BIT; /* in bits */
-
- records_lost += 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);
- header->ctx.events_discarded = records_lost;
-}
-
-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 void client_content_size_field(const struct lttng_ust_lib_ring_buffer_config *config,
- size_t *offset, size_t *length)
-{
- *offset = offsetof(struct packet_header, ctx.content_size);
- *length = sizeof(((struct packet_header *) NULL)->ctx.content_size);
-}
-
-static void client_packet_size_field(const struct lttng_ust_lib_ring_buffer_config *config,
- size_t *offset, size_t *length)
-{
- *offset = offsetof(struct packet_header, ctx.packet_size);
- *length = sizeof(((struct packet_header *) NULL)->ctx.packet_size);
-}
-
-static struct packet_header *client_packet_header(struct lttng_ust_lib_ring_buffer *buf,
- struct lttng_ust_shm_handle *handle)
-{
- return lib_ring_buffer_read_offset_address(&buf->backend, 0, handle);
-}
-
-static int client_timestamp_begin(struct lttng_ust_lib_ring_buffer *buf,
- struct lttng_ust_shm_handle *handle,
- uint64_t *timestamp_begin)
-{
- struct packet_header *header;
-
- header = client_packet_header(buf, handle);
- if (!header)
- return -1;
- *timestamp_begin = header->ctx.timestamp_begin;
- return 0;
-}
-
-static int client_timestamp_end(struct lttng_ust_lib_ring_buffer *buf,
- struct lttng_ust_shm_handle *handle,
- uint64_t *timestamp_end)
-{
- struct packet_header *header;
-
- header = client_packet_header(buf, handle);
- if (!header)
- return -1;
- *timestamp_end = header->ctx.timestamp_end;
- return 0;
-}
-
-static int client_events_discarded(struct lttng_ust_lib_ring_buffer *buf,
- struct lttng_ust_shm_handle *handle,
- uint64_t *events_discarded)
-{
- struct packet_header *header;
-
- header = client_packet_header(buf, handle);
- if (!header)
- return -1;
- *events_discarded = header->ctx.events_discarded;
- return 0;
-}
-
-static int client_content_size(struct lttng_ust_lib_ring_buffer *buf,
- struct lttng_ust_shm_handle *handle,
- uint64_t *content_size)
-{
- struct packet_header *header;
-
- header = client_packet_header(buf, handle);
- if (!header)
- return -1;
- *content_size = header->ctx.content_size;
- return 0;
-}
-
-static int client_packet_size(struct lttng_ust_lib_ring_buffer *buf,
- struct lttng_ust_shm_handle *handle,
- uint64_t *packet_size)
-{
- struct packet_header *header;
-
- header = client_packet_header(buf, handle);
- if (!header)
- return -1;
- *packet_size = header->ctx.packet_size;
- return 0;
-}
-
-static int client_stream_id(struct lttng_ust_lib_ring_buffer *buf,
- struct lttng_ust_shm_handle *handle,
- uint64_t *stream_id)
-{
- struct channel *chan = shmp(handle, buf->backend.chan);
- struct lttng_channel *lttng_chan = channel_get_private(chan);
-
- *stream_id = lttng_chan->id;
-
- return 0;
-}
-
-static int client_current_timestamp(struct lttng_ust_lib_ring_buffer *buf,
- struct lttng_ust_shm_handle *handle,
- uint64_t *ts)
-{
- struct channel *chan;
-
- chan = shmp(handle, handle->chan);
- *ts = client_ring_buffer_clock_read(chan);
-
- return 0;
-}
-
-static int client_sequence_number(struct lttng_ust_lib_ring_buffer *buf,
- struct lttng_ust_shm_handle *handle,
- uint64_t *seq)
-{
- struct packet_header *header;
-
- header = client_packet_header(buf, handle);
- if (!header)
- return -1;
- *seq = header->ctx.packet_seq_num;
- return 0;
-}
-
-static int client_instance_id(struct lttng_ust_lib_ring_buffer *buf,
- struct lttng_ust_shm_handle *handle,
- uint64_t *id)
-{
- *id = buf->backend.cpu;
-
- return 0;
-}
-
-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,
- .content_size_field = client_content_size_field,
- .packet_size_field = client_packet_size_field,
- },
- .timestamp_begin = client_timestamp_begin,
- .timestamp_end = client_timestamp_end,
- .events_discarded = client_events_discarded,
- .content_size = client_content_size,
- .packet_size = client_packet_size,
- .stream_id = client_stream_id,
- .current_timestamp = client_current_timestamp,
- .sequence_number = client_sequence_number,
- .instance_id = client_instance_id,
-};
-
-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,
- .cb.content_size_field = client_content_size_field,
- .cb.packet_size_field = client_packet_size_field,
-
- .tsc_bits = LTTNG_COMPACT_TSC_BITS,
- .alloc = RING_BUFFER_ALLOC_PER_CPU,
- .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 = LTTNG_CLIENT_WAKEUP,
- .client_type = LTTNG_CLIENT_TYPE,
-
- .cb_ptr = &client_cb.parent,
-};
-
-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)
-{
- struct lttng_channel *lttng_chan = channel_get_private(ctx->chan);
- struct lttng_event *event = ctx->priv;
- struct lttng_stack_ctx *lttng_ctx = ctx->priv2;
- struct lttng_client_ctx client_ctx;
- int ret, cpu;
-
- /* Compute internal size of context structures. */
-
- if (lttng_ctx) {
- /* 2.8+ probe ABI. */
- ctx_get_struct_size(lttng_ctx->chan_ctx, &client_ctx.packet_context_len,
- APP_CTX_ENABLED);
- ctx_get_struct_size(lttng_ctx->event_ctx, &client_ctx.event_context_len,
- APP_CTX_ENABLED);
- } else {
- /* Pre 2.8 probe ABI. */
- ctx_get_struct_size(lttng_chan->ctx, &client_ctx.packet_context_len,
- APP_CTX_DISABLED);
- ctx_get_struct_size(event->ctx, &client_ctx.event_context_len,
- APP_CTX_DISABLED);
- }
-
- cpu = lib_ring_buffer_get_cpu(&client_config);
- if (cpu < 0)
- return -EPERM;
- ctx->cpu = cpu;
-
- switch (lttng_chan->header_type) {
- case 1: /* compact */
- if (event_id > 30)
- ctx->rflags |= LTTNG_RFLAG_EXTENDED;
- break;
- case 2: /* large */
- if (event_id > 65534)
- ctx->rflags |= LTTNG_RFLAG_EXTENDED;
- break;
- default:
- WARN_ON_ONCE(1);
- }
-
- ret = lib_ring_buffer_reserve(&client_config, ctx, &client_ctx);
- if (caa_unlikely(ret))
- goto put;
- 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)) {
- ret = -EPERM;
- goto put;
- }
- }
- lttng_write_event_header(&client_config, ctx, event_id);
- return 0;
-put:
- lib_ring_buffer_put_cpu(&client_config);
- return ret;
-}
-
-static
-void lttng_event_commit(struct lttng_ust_lib_ring_buffer_ctx *ctx)
-{
- lib_ring_buffer_commit(&client_config, ctx);
- lib_ring_buffer_put_cpu(&client_config);
-}
-
-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
-void lttng_event_strcpy(struct lttng_ust_lib_ring_buffer_ctx *ctx, const char *src,
- size_t len)
-{
- lib_ring_buffer_strcpy(&client_config, ctx, src, len, '#');
-}
-
-#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 cpu;
-
- for_each_channel_cpu(cpu, chan) {
- int shm_fd, wait_fd, wakeup_fd;
- uint64_t memory_map_size;
-
- buf = channel_get_ring_buffer(&client_config, chan,
- cpu, 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 = NULL, /* Would be racy anyway */
- .is_finalized = lttng_is_finalized,
- .is_disabled = lttng_is_disabled,
- .flush_buffer = lttng_flush_buffer,
- .event_strcpy = lttng_event_strcpy,
- },
- .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);
-}