/*
- * ring_buffer_backend.c
+ * SPDX-License-Identifier: LGPL-2.1-only
*
- * Copyright (C) 2005-2010 - Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
- *
- * Dual LGPL v2.1/GPL v2 license.
+ * Copyright (C) 2005-2012 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
*/
+#define _LGPL_SOURCE
+#include <stddef.h>
+#include <stdint.h>
+#include <unistd.h>
#include <urcu/arch.h>
+#include <limits.h>
-#include "ust/core.h"
-
-#include <ust/ringbuffer-config.h>
+#include <lttng/align.h>
+#include <lttng/ringbuffer-config.h>
+#include "vatomic.h"
#include "backend.h"
#include "frontend.h"
#include "smp.h"
* @extra_reader_sb: need extra subbuffer for reader
*/
static
-int lib_ring_buffer_backend_allocate(const struct lib_ring_buffer_config *config,
- struct lib_ring_buffer_backend *bufb,
+int lib_ring_buffer_backend_allocate(const struct lttng_ust_lib_ring_buffer_config *config,
+ struct lttng_ust_lib_ring_buffer_backend *bufb,
size_t size, size_t num_subbuf,
int extra_reader_sb,
- struct shm_handle *handle,
+ struct lttng_ust_shm_handle *handle,
struct shm_object *shmobj)
{
- struct channel_backend *chanb = &shmp(handle, bufb->chan)->backend;
+ struct channel_backend *chanb;
unsigned long subbuf_size, mmap_offset = 0;
unsigned long num_subbuf_alloc;
unsigned long i;
+ long page_size;
+
+ chanb = &shmp(handle, bufb->chan)->backend;
+ if (!chanb)
+ return -EINVAL;
subbuf_size = chanb->subbuf_size;
num_subbuf_alloc = num_subbuf;
if (extra_reader_sb)
num_subbuf_alloc++;
- align_shm(shmobj, __alignof__(struct lib_ring_buffer_backend_pages_shmp));
+ page_size = LTTNG_UST_PAGE_SIZE;
+ if (page_size <= 0) {
+ goto page_size_error;
+ }
+
+ align_shm(shmobj, __alignof__(struct lttng_ust_lib_ring_buffer_backend_pages_shmp));
set_shmp(bufb->array, zalloc_shm(shmobj,
- sizeof(struct lib_ring_buffer_backend_pages_shmp) * num_subbuf_alloc));
- if (unlikely(!shmp(handle, bufb->array)))
+ sizeof(struct lttng_ust_lib_ring_buffer_backend_pages_shmp) * num_subbuf_alloc));
+ if (caa_unlikely(!shmp(handle, bufb->array)))
goto array_error;
/*
* This is the largest element (the buffer pages) which needs to
- * be aligned on PAGE_SIZE.
+ * be aligned on page size.
*/
- align_shm(shmobj, PAGE_SIZE);
+ align_shm(shmobj, page_size);
set_shmp(bufb->memory_map, zalloc_shm(shmobj,
subbuf_size * num_subbuf_alloc));
- if (unlikely(!shmp(handle, bufb->memory_map)))
+ if (caa_unlikely(!shmp(handle, bufb->memory_map)))
goto memory_map_error;
/* Allocate backend pages array elements */
for (i = 0; i < num_subbuf_alloc; i++) {
- align_shm(shmobj, __alignof__(struct lib_ring_buffer_backend_pages));
+ align_shm(shmobj, __alignof__(struct lttng_ust_lib_ring_buffer_backend_pages));
set_shmp(shmp_index(handle, bufb->array, i)->shmp,
zalloc_shm(shmobj,
- sizeof(struct lib_ring_buffer_backend_pages)));
+ sizeof(struct lttng_ust_lib_ring_buffer_backend_pages)));
if (!shmp(handle, shmp_index(handle, bufb->array, i)->shmp))
goto free_array;
}
/* Allocate write-side subbuffer table */
- align_shm(shmobj, __alignof__(struct lib_ring_buffer_backend_subbuffer));
+ align_shm(shmobj, __alignof__(struct lttng_ust_lib_ring_buffer_backend_subbuffer));
set_shmp(bufb->buf_wsb, zalloc_shm(shmobj,
- sizeof(struct lib_ring_buffer_backend_subbuffer)
+ sizeof(struct lttng_ust_lib_ring_buffer_backend_subbuffer)
* num_subbuf));
- if (unlikely(!shmp(handle, bufb->buf_wsb)))
+ if (caa_unlikely(!shmp(handle, bufb->buf_wsb)))
goto free_array;
- for (i = 0; i < num_subbuf; i++)
- shmp_index(handle, bufb->buf_wsb, i)->id = subbuffer_id(config, 0, 1, i);
+ for (i = 0; i < num_subbuf; i++) {
+ struct lttng_ust_lib_ring_buffer_backend_subbuffer *sb;
+
+ sb = shmp_index(handle, bufb->buf_wsb, i);
+ if (!sb)
+ goto free_array;
+ sb->id = subbuffer_id(config, 0, 1, i);
+ }
/* Assign read-side subbuffer table */
if (extra_reader_sb)
else
bufb->buf_rsb.id = subbuffer_id(config, 0, 1, 0);
+ /* Allocate subbuffer packet counter table */
+ align_shm(shmobj, __alignof__(struct lttng_ust_lib_ring_buffer_backend_counts));
+ set_shmp(bufb->buf_cnt, zalloc_shm(shmobj,
+ sizeof(struct lttng_ust_lib_ring_buffer_backend_counts)
+ * num_subbuf));
+ if (caa_unlikely(!shmp(handle, bufb->buf_cnt)))
+ goto free_wsb;
+
/* Assign pages to page index */
for (i = 0; i < num_subbuf_alloc; i++) {
+ struct lttng_ust_lib_ring_buffer_backend_pages_shmp *sbp;
+ struct lttng_ust_lib_ring_buffer_backend_pages *pages;
struct shm_ref ref;
ref.index = bufb->memory_map._ref.index;
ref.offset = bufb->memory_map._ref.offset;
ref.offset += i * subbuf_size;
- set_shmp(shmp(handle, shmp_index(handle, bufb->array, i)->shmp)->p,
- ref);
+ sbp = shmp_index(handle, bufb->array, i);
+ if (!sbp)
+ goto free_array;
+ pages = shmp(handle, sbp->shmp);
+ if (!pages)
+ goto free_array;
+ set_shmp(pages->p, ref);
if (config->output == RING_BUFFER_MMAP) {
- shmp(handle, shmp_index(handle, bufb->array, i)->shmp)->mmap_offset = mmap_offset;
+ pages->mmap_offset = mmap_offset;
mmap_offset += subbuf_size;
}
}
-
return 0;
+free_wsb:
+ /* bufb->buf_wsb will be freed by shm teardown */
free_array:
/* bufb->array[i] will be freed by shm teardown */
memory_map_error:
/* bufb->array will be freed by shm teardown */
array_error:
+page_size_error:
return -ENOMEM;
}
-int lib_ring_buffer_backend_create(struct lib_ring_buffer_backend *bufb,
+int lib_ring_buffer_backend_create(struct lttng_ust_lib_ring_buffer_backend *bufb,
struct channel_backend *chanb, int cpu,
- struct shm_handle *handle,
+ struct lttng_ust_shm_handle *handle,
struct shm_object *shmobj)
{
- const struct lib_ring_buffer_config *config = chanb->config;
+ const struct lttng_ust_lib_ring_buffer_config *config = &chanb->config;
set_shmp(bufb->chan, handle->chan._ref);
bufb->cpu = cpu;
handle, shmobj);
}
-void lib_ring_buffer_backend_free(struct lib_ring_buffer_backend *bufb)
+void lib_ring_buffer_backend_reset(struct lttng_ust_lib_ring_buffer_backend *bufb,
+ struct lttng_ust_shm_handle *handle)
{
- /* bufb->buf_wsb will be freed by shm teardown */
- /* bufb->array[i] will be freed by shm teardown */
- /* bufb->array will be freed by shm teardown */
- bufb->allocated = 0;
-}
-
-void lib_ring_buffer_backend_reset(struct lib_ring_buffer_backend *bufb,
- struct shm_handle *handle)
-{
- struct channel_backend *chanb = &shmp(handle, bufb->chan)->backend;
- const struct lib_ring_buffer_config *config = chanb->config;
+ struct channel_backend *chanb;
+ const struct lttng_ust_lib_ring_buffer_config *config;
unsigned long num_subbuf_alloc;
unsigned int i;
+ chanb = &shmp(handle, bufb->chan)->backend;
+ if (!chanb)
+ return;
+ config = &chanb->config;
+
num_subbuf_alloc = chanb->num_subbuf;
if (chanb->extra_reader_sb)
num_subbuf_alloc++;
- for (i = 0; i < chanb->num_subbuf; i++)
- shmp_index(handle, bufb->buf_wsb, i)->id = subbuffer_id(config, 0, 1, i);
+ for (i = 0; i < chanb->num_subbuf; i++) {
+ struct lttng_ust_lib_ring_buffer_backend_subbuffer *sb;
+
+ sb = shmp_index(handle, bufb->buf_wsb, i);
+ if (!sb)
+ return;
+ sb->id = subbuffer_id(config, 0, 1, i);
+ }
if (chanb->extra_reader_sb)
bufb->buf_rsb.id = subbuffer_id(config, 0, 1,
num_subbuf_alloc - 1);
bufb->buf_rsb.id = subbuffer_id(config, 0, 1, 0);
for (i = 0; i < num_subbuf_alloc; i++) {
+ struct lttng_ust_lib_ring_buffer_backend_pages_shmp *sbp;
+ struct lttng_ust_lib_ring_buffer_backend_pages *pages;
+
+ sbp = shmp_index(handle, bufb->array, i);
+ if (!sbp)
+ return;
+ pages = shmp(handle, sbp->shmp);
+ if (!pages)
+ return;
/* Don't reset mmap_offset */
- v_set(config, &shmp(handle, shmp_index(handle, bufb->array, i)->shmp)->records_commit, 0);
- v_set(config, &shmp(handle, shmp_index(handle, bufb->array, i)->shmp)->records_unread, 0);
- shmp(handle, shmp_index(handle, bufb->array, i)->shmp)->data_size = 0;
+ v_set(config, &pages->records_commit, 0);
+ v_set(config, &pages->records_unread, 0);
+ pages->data_size = 0;
/* Don't reset backend page and virt addresses */
}
/* Don't reset num_pages_per_subbuf, cpu, allocated */
void channel_backend_reset(struct channel_backend *chanb)
{
struct channel *chan = caa_container_of(chanb, struct channel, backend);
- const struct lib_ring_buffer_config *config = chanb->config;
+ const struct lttng_ust_lib_ring_buffer_config *config = &chanb->config;
/*
* Don't reset buf_size, subbuf_size, subbuf_size_order,
* @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)
+ * @subbuf_size: size of sub-buffers (> page size, power of 2)
* @num_subbuf: number of sub-buffers (power of 2)
- * @shm_handle: shared memory handle
+ * @lttng_ust_shm_handle: shared memory handle
+ * @stream_fds: stream file descriptors.
*
* Returns channel pointer if successful, %NULL otherwise.
*
*/
int channel_backend_init(struct channel_backend *chanb,
const char *name,
- const struct lib_ring_buffer_config *config,
- void *priv, size_t subbuf_size, size_t num_subbuf,
- struct shm_handle *handle)
+ const struct lttng_ust_lib_ring_buffer_config *config,
+ size_t subbuf_size, size_t num_subbuf,
+ struct lttng_ust_shm_handle *handle,
+ const int *stream_fds)
{
struct channel *chan = caa_container_of(chanb, struct channel, backend);
unsigned int i;
int ret;
size_t shmsize = 0, num_subbuf_alloc;
+ long page_size;
if (!name)
return -EPERM;
- if (!(subbuf_size && num_subbuf))
- return -EPERM;
-
+ page_size = LTTNG_UST_PAGE_SIZE;
+ if (page_size <= 0) {
+ return -ENOMEM;
+ }
/* Check that the subbuffer size is larger than a page. */
- if (subbuf_size < PAGE_SIZE)
+ if (subbuf_size < page_size)
return -EINVAL;
/*
- * Make sure the number of subbuffers and subbuffer size are power of 2.
+ * Make sure the number of subbuffers and subbuffer size are
+ * power of 2, and nonzero.
+ */
+ if (!subbuf_size || (subbuf_size & (subbuf_size - 1)))
+ return -EINVAL;
+ if (!num_subbuf || (num_subbuf & (num_subbuf - 1)))
+ return -EINVAL;
+ /*
+ * Overwrite mode buffers require at least 2 subbuffers per
+ * buffer.
*/
- CHAN_WARN_ON(chanb, hweight32(subbuf_size) != 1);
- CHAN_WARN_ON(chanb, hweight32(num_subbuf) != 1);
+ if (config->mode == RING_BUFFER_OVERWRITE && num_subbuf < 2)
+ return -EINVAL;
ret = subbuffer_id_check_index(config, num_subbuf);
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);
chanb->num_subbuf = num_subbuf;
strncpy(chanb->name, name, NAME_MAX);
chanb->name[NAME_MAX - 1] = '\0';
- chanb->config = config;
+ memcpy(&chanb->config, config, sizeof(*config));
/* Per-cpu buffer size: control (prior to backend) */
- shmsize = offset_align(shmsize, __alignof__(struct lib_ring_buffer));
- shmsize += sizeof(struct lib_ring_buffer);
+ shmsize = lttng_ust_offset_align(shmsize, __alignof__(struct lttng_ust_lib_ring_buffer));
+ shmsize += sizeof(struct lttng_ust_lib_ring_buffer);
+ shmsize += lttng_ust_offset_align(shmsize, __alignof__(struct commit_counters_hot));
+ shmsize += sizeof(struct commit_counters_hot) * num_subbuf;
+ shmsize += lttng_ust_offset_align(shmsize, __alignof__(struct commit_counters_cold));
+ shmsize += sizeof(struct commit_counters_cold) * num_subbuf;
+ /* Sampled timestamp end */
+ shmsize += lttng_ust_offset_align(shmsize, __alignof__(uint64_t));
+ shmsize += sizeof(uint64_t) * num_subbuf;
/* Per-cpu buffer size: backend */
/* num_subbuf + 1 is the worse case */
num_subbuf_alloc = num_subbuf + 1;
- shmsize += offset_align(shmsize, __alignof__(struct lib_ring_buffer_backend_pages_shmp));
- shmsize += sizeof(struct lib_ring_buffer_backend_pages_shmp) * num_subbuf_alloc;
- shmsize += offset_align(shmsize, PAGE_SIZE);
+ shmsize += lttng_ust_offset_align(shmsize, __alignof__(struct lttng_ust_lib_ring_buffer_backend_pages_shmp));
+ shmsize += sizeof(struct lttng_ust_lib_ring_buffer_backend_pages_shmp) * num_subbuf_alloc;
+ shmsize += lttng_ust_offset_align(shmsize, page_size);
shmsize += subbuf_size * num_subbuf_alloc;
- shmsize += offset_align(shmsize, __alignof__(struct lib_ring_buffer_backend_pages));
- shmsize += sizeof(struct lib_ring_buffer_backend_pages) * num_subbuf_alloc;
- shmsize += offset_align(shmsize, __alignof__(struct lib_ring_buffer_backend_subbuffer));
- shmsize += sizeof(struct lib_ring_buffer_backend_subbuffer) * num_subbuf;
- /* Per-cpu buffer size: control (after backend) */
- shmsize += offset_align(shmsize, __alignof__(struct commit_counters_hot));
- shmsize += sizeof(struct commit_counters_hot) * num_subbuf;
- shmsize += offset_align(shmsize, __alignof__(struct commit_counters_cold));
- shmsize += sizeof(struct commit_counters_cold) * num_subbuf;
+ shmsize += lttng_ust_offset_align(shmsize, __alignof__(struct lttng_ust_lib_ring_buffer_backend_pages));
+ shmsize += sizeof(struct lttng_ust_lib_ring_buffer_backend_pages) * num_subbuf_alloc;
+ shmsize += lttng_ust_offset_align(shmsize, __alignof__(struct lttng_ust_lib_ring_buffer_backend_subbuffer));
+ shmsize += sizeof(struct lttng_ust_lib_ring_buffer_backend_subbuffer) * num_subbuf;
+ shmsize += lttng_ust_offset_align(shmsize, __alignof__(struct lttng_ust_lib_ring_buffer_backend_counts));
+ shmsize += sizeof(struct lttng_ust_lib_ring_buffer_backend_counts) * num_subbuf;
if (config->alloc == RING_BUFFER_ALLOC_PER_CPU) {
- struct lib_ring_buffer *buf;
+ struct lttng_ust_lib_ring_buffer *buf;
/*
* We need to allocate for all possible cpus.
*/
for_each_possible_cpu(i) {
struct shm_object *shmobj;
- shmobj = shm_object_table_append(handle->table, shmsize);
+ shmobj = shm_object_table_alloc(handle->table, shmsize,
+ SHM_OBJECT_SHM, stream_fds[i], i);
if (!shmobj)
goto end;
- align_shm(shmobj, __alignof__(struct lib_ring_buffer));
- set_shmp(chanb->buf[i].shmp, zalloc_shm(shmobj, sizeof(struct lib_ring_buffer)));
+ align_shm(shmobj, __alignof__(struct lttng_ust_lib_ring_buffer));
+ set_shmp(chanb->buf[i].shmp, zalloc_shm(shmobj, sizeof(struct lttng_ust_lib_ring_buffer)));
buf = shmp(handle, chanb->buf[i].shmp);
if (!buf)
goto end;
}
} else {
struct shm_object *shmobj;
- struct lib_ring_buffer *buf;
+ struct lttng_ust_lib_ring_buffer *buf;
- shmobj = shm_object_table_append(handle->table, shmsize);
+ shmobj = shm_object_table_alloc(handle->table, shmsize,
+ SHM_OBJECT_SHM, stream_fds[0], -1);
if (!shmobj)
goto end;
- align_shm(shmobj, __alignof__(struct lib_ring_buffer));
- set_shmp(chanb->buf[0].shmp, zalloc_shm(shmobj, sizeof(struct lib_ring_buffer)));
+ align_shm(shmobj, __alignof__(struct lttng_ust_lib_ring_buffer));
+ set_shmp(chanb->buf[0].shmp, zalloc_shm(shmobj, sizeof(struct lttng_ust_lib_ring_buffer)));
buf = shmp(handle, chanb->buf[0].shmp);
if (!buf)
goto end;
+ set_shmp(buf->self, chanb->buf[0].shmp._ref);
ret = lib_ring_buffer_create(buf, chanb, -1,
handle, shmobj);
if (ret)
return 0;
free_bufs:
- if (config->alloc == RING_BUFFER_ALLOC_PER_CPU) {
- for_each_possible_cpu(i) {
- struct lib_ring_buffer *buf = shmp(handle, chanb->buf[i].shmp);
-
- if (!buf->backend.allocated)
- continue;
- lib_ring_buffer_free(buf, handle);
- }
- }
/* We only free the buffer data upon shm teardown */
end:
return -ENOMEM;
* Destroy all channel buffers and frees the channel.
*/
void channel_backend_free(struct channel_backend *chanb,
- struct shm_handle *handle)
+ struct lttng_ust_shm_handle *handle)
{
- const struct lib_ring_buffer_config *config = chanb->config;
- unsigned int i;
-
- if (config->alloc == RING_BUFFER_ALLOC_PER_CPU) {
- for_each_possible_cpu(i) {
- struct lib_ring_buffer *buf = shmp(handle, chanb->buf[i].shmp);
-
- if (!buf->backend.allocated)
- continue;
- lib_ring_buffer_free(buf, handle);
- }
- } else {
- struct lib_ring_buffer *buf = shmp(handle, chanb->buf[0].shmp);
-
- CHAN_WARN_ON(chanb, !buf->backend.allocated);
- lib_ring_buffer_free(buf, handle);
- }
- /* We only free the buffer data upon shm teardown */
+ /* SHM teardown takes care of everything */
}
/**
* Should be protected by get_subbuf/put_subbuf.
* Returns the length copied.
*/
-size_t lib_ring_buffer_read(struct lib_ring_buffer_backend *bufb, size_t offset,
- void *dest, size_t len, struct shm_handle *handle)
+size_t lib_ring_buffer_read(struct lttng_ust_lib_ring_buffer_backend *bufb, size_t offset,
+ void *dest, size_t len, struct lttng_ust_shm_handle *handle)
{
- struct channel_backend *chanb = &shmp(handle, bufb->chan)->backend;
- const struct lib_ring_buffer_config *config = chanb->config;
+ struct channel_backend *chanb;
+ const struct lttng_ust_lib_ring_buffer_config *config;
ssize_t orig_len;
- struct lib_ring_buffer_backend_pages_shmp *rpages;
+ struct lttng_ust_lib_ring_buffer_backend_pages_shmp *rpages;
+ struct lttng_ust_lib_ring_buffer_backend_pages *backend_pages;
unsigned long sb_bindex, id;
+ void *src;
+ chanb = &shmp(handle, bufb->chan)->backend;
+ if (!chanb)
+ return 0;
+ config = &chanb->config;
orig_len = len;
offset &= chanb->buf_size - 1;
- if (unlikely(!len))
+ if (caa_unlikely(!len))
return 0;
id = bufb->buf_rsb.id;
sb_bindex = subbuffer_id_get_index(config, id);
rpages = shmp_index(handle, bufb->array, sb_bindex);
+ if (!rpages)
+ return 0;
/*
* Underlying layer should never ask for reads across
* subbuffers.
CHAN_WARN_ON(chanb, offset >= chanb->buf_size);
CHAN_WARN_ON(chanb, config->mode == RING_BUFFER_OVERWRITE
&& subbuffer_id_is_noref(config, id));
- memcpy(dest, shmp_index(handle, shmp(handle, rpages->shmp)->p, offset & (chanb->subbuf_size - 1)), len);
+ backend_pages = shmp(handle, rpages->shmp);
+ if (!backend_pages)
+ return 0;
+ src = shmp_index(handle, backend_pages->p, offset & (chanb->subbuf_size - 1));
+ if (caa_unlikely(!src))
+ return 0;
+ memcpy(dest, src, len);
return orig_len;
}
* @dest : destination address
* @len : destination's length
*
- * return string's length
+ * Return string's length, or -EINVAL on error.
* Should be protected by get_subbuf/put_subbuf.
+ * Destination length should be at least 1 to hold '\0'.
*/
-int lib_ring_buffer_read_cstr(struct lib_ring_buffer_backend *bufb, size_t offset,
- void *dest, size_t len, struct shm_handle *handle)
+int lib_ring_buffer_read_cstr(struct lttng_ust_lib_ring_buffer_backend *bufb, size_t offset,
+ void *dest, size_t len, struct lttng_ust_shm_handle *handle)
{
- struct channel_backend *chanb = &shmp(handle, bufb->chan)->backend;
- const struct lib_ring_buffer_config *config = chanb->config;
+ struct channel_backend *chanb;
+ const struct lttng_ust_lib_ring_buffer_config *config;
ssize_t string_len, orig_offset;
char *str;
- struct lib_ring_buffer_backend_pages_shmp *rpages;
+ struct lttng_ust_lib_ring_buffer_backend_pages_shmp *rpages;
+ struct lttng_ust_lib_ring_buffer_backend_pages *backend_pages;
unsigned long sb_bindex, id;
+ chanb = &shmp(handle, bufb->chan)->backend;
+ if (!chanb)
+ return -EINVAL;
+ config = &chanb->config;
+ if (caa_unlikely(!len))
+ return -EINVAL;
offset &= chanb->buf_size - 1;
orig_offset = offset;
id = bufb->buf_rsb.id;
sb_bindex = subbuffer_id_get_index(config, id);
rpages = shmp_index(handle, bufb->array, sb_bindex);
+ if (!rpages)
+ return -EINVAL;
/*
* Underlying layer should never ask for reads across
* subbuffers.
CHAN_WARN_ON(chanb, offset >= chanb->buf_size);
CHAN_WARN_ON(chanb, config->mode == RING_BUFFER_OVERWRITE
&& subbuffer_id_is_noref(config, id));
- str = shmp_index(handle, shmp(handle, rpages->shmp)->p, offset & (chanb->subbuf_size - 1));
+ backend_pages = shmp(handle, rpages->shmp);
+ if (!backend_pages)
+ return -EINVAL;
+ str = shmp_index(handle, backend_pages->p, offset & (chanb->subbuf_size - 1));
+ if (caa_unlikely(!str))
+ return -EINVAL;
string_len = strnlen(str, len);
if (dest && len) {
memcpy(dest, str, string_len);
*
* Return the address where a given offset is located (for read).
* Should be used to get the current subbuffer header pointer. Given we know
- * it's never on a page boundary, it's safe to write directly to this address,
- * as long as the write is never bigger than a page size.
+ * it's never on a page boundary, it's safe to read/write directly
+ * from/to this address, as long as the read/write is never bigger than
+ * a page size.
*/
-void *lib_ring_buffer_read_offset_address(struct lib_ring_buffer_backend *bufb,
+void *lib_ring_buffer_read_offset_address(struct lttng_ust_lib_ring_buffer_backend *bufb,
size_t offset,
- struct shm_handle *handle)
+ struct lttng_ust_shm_handle *handle)
{
- struct lib_ring_buffer_backend_pages_shmp *rpages;
- struct channel_backend *chanb = &shmp(handle, bufb->chan)->backend;
- const struct lib_ring_buffer_config *config = chanb->config;
+ struct lttng_ust_lib_ring_buffer_backend_pages_shmp *rpages;
+ struct lttng_ust_lib_ring_buffer_backend_pages *backend_pages;
+ struct channel_backend *chanb;
+ const struct lttng_ust_lib_ring_buffer_config *config;
unsigned long sb_bindex, id;
+ chanb = &shmp(handle, bufb->chan)->backend;
+ if (!chanb)
+ return NULL;
+ config = &chanb->config;
offset &= chanb->buf_size - 1;
id = bufb->buf_rsb.id;
sb_bindex = subbuffer_id_get_index(config, id);
rpages = shmp_index(handle, bufb->array, sb_bindex);
+ if (!rpages)
+ return NULL;
CHAN_WARN_ON(chanb, config->mode == RING_BUFFER_OVERWRITE
&& subbuffer_id_is_noref(config, id));
- return shmp_index(handle, shmp(handle, rpages->shmp)->p, offset & (chanb->subbuf_size - 1));
+ backend_pages = shmp(handle, rpages->shmp);
+ if (!backend_pages)
+ return NULL;
+ return shmp_index(handle, backend_pages->p, offset & (chanb->subbuf_size - 1));
}
/**
* it's always at the beginning of a page, it's safe to write directly to this
* address, as long as the write is never bigger than a page size.
*/
-void *lib_ring_buffer_offset_address(struct lib_ring_buffer_backend *bufb,
+void *lib_ring_buffer_offset_address(struct lttng_ust_lib_ring_buffer_backend *bufb,
size_t offset,
- struct shm_handle *handle)
+ struct lttng_ust_shm_handle *handle)
{
size_t sbidx;
- struct lib_ring_buffer_backend_pages_shmp *rpages;
- struct channel_backend *chanb = &shmp(handle, bufb->chan)->backend;
- const struct lib_ring_buffer_config *config = chanb->config;
+ struct lttng_ust_lib_ring_buffer_backend_pages_shmp *rpages;
+ struct lttng_ust_lib_ring_buffer_backend_pages *backend_pages;
+ struct channel_backend *chanb;
+ const struct lttng_ust_lib_ring_buffer_config *config;
unsigned long sb_bindex, id;
- void *ret;
+ struct lttng_ust_lib_ring_buffer_backend_subbuffer *sb;
+ chanb = &shmp(handle, bufb->chan)->backend;
+ if (!chanb)
+ return NULL;
+ config = &chanb->config;
offset &= chanb->buf_size - 1;
sbidx = offset >> chanb->subbuf_size_order;
- id = shmp_index(handle, bufb->buf_wsb, sbidx)->id;
+ sb = shmp_index(handle, bufb->buf_wsb, sbidx);
+ if (!sb)
+ return NULL;
+ id = sb->id;
sb_bindex = subbuffer_id_get_index(config, id);
rpages = shmp_index(handle, bufb->array, sb_bindex);
+ if (!rpages)
+ return NULL;
CHAN_WARN_ON(chanb, config->mode == RING_BUFFER_OVERWRITE
&& subbuffer_id_is_noref(config, id));
- return shmp_index(handle, shmp(handle, rpages->shmp)->p, offset & (chanb->subbuf_size - 1));
+ backend_pages = shmp(handle, rpages->shmp);
+ if (!backend_pages)
+ return NULL;
+ return shmp_index(handle, backend_pages->p, offset & (chanb->subbuf_size - 1));
}
projects / lttng-ust.git / blobdiff