/*
* ring_buffer_frontend.c
*
- * (C) Copyright 2005-2010 - Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
+ * Copyright (C) 2005-2012 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
+ *
*
* Ring buffer wait-free buffer synchronization. Producer-consumer and flight
* recorder (overwrite) modes. See thesis:
* - splice one subbuffer worth of data to a pipe
* - splice the data from pipe to disk/network
* - put_subbuf
- *
- * Dual LGPL v2.1/GPL v2 license.
*/
#define _GNU_SOURCE
#include "backend.h"
#include "frontend.h"
#include "shm.h"
+#include "tlsfixup.h"
#ifndef max
#define max(a, b) ((a) > (b) ? (a) : (b))
#endif
+/* Print DBG() messages about events lost only every 1048576 hits */
+#define DBG_PRINT_NR_LOST (1UL << 20)
+
/*
* Use POSIX SHM: shm_open(3) and shm_unlink(3).
* close(2) to close the fd returned by shm_open.
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, char **shm_path,
+ int **wait_fd, char **wait_pipe_path, uint64_t **memory_map_size)
{
int ret, cpu;
size_t shmsize, chansize;
lib_ring_buffer_start_read_timer(buf, handle);
}
ref = &handle->chan._ref;
- shm_get_object_data(handle, ref, shm_fd, wait_fd, memory_map_size);
+ shm_get_object_data(handle, ref, shm_fd, shm_path, wait_fd, wait_pipe_path, memory_map_size);
return handle;
error_backend_init:
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,
+ int **shm_fd, char **shm_path,
+ int **wait_fd, char **wait_pipe_path,
uint64_t **memory_map_size)
{
struct shm_ref *ref;
if (config->alloc == RING_BUFFER_ALLOC_GLOBAL) {
ref = &chan->backend.buf[0].shmp._ref;
- shm_get_object_data(handle, ref, shm_fd, wait_fd,
- memory_map_size);
+ shm_get_object_data(handle, ref, shm_fd, shm_path,
+ wait_fd, wait_pipe_path, memory_map_size);
return shmp(handle, chan->backend.buf[0].shmp);
} else {
if (cpu >= num_possible_cpus())
return NULL;
ref = &chan->backend.buf[cpu].shmp._ref;
- shm_get_object_data(handle, ref, shm_fd, wait_fd,
- memory_map_size);
+ shm_get_object_data(handle, ref, shm_fd, shm_path,
+ wait_fd, wait_pipe_path, memory_map_size);
return shmp(handle, chan->backend.buf[cpu].shmp);
}
}
const struct lttng_ust_lib_ring_buffer_config *config = &chan->backend.config;
void *priv = channel_get_private(chan);
- DBG("ring buffer %s, cpu %d: %lu records written, "
- "%lu records overrun\n",
- chan->backend.name, cpu,
- v_read(config, &buf->records_count),
- v_read(config, &buf->records_overrun));
-
- if (v_read(config, &buf->records_lost_full)
- || v_read(config, &buf->records_lost_wrap)
- || v_read(config, &buf->records_lost_big))
- 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,
- v_read(config, &buf->records_lost_full),
- v_read(config, &buf->records_lost_wrap),
- v_read(config, &buf->records_lost_big));
-
+ if (!strcmp(chan->backend.name, "relay-metadata-mmap")) {
+ DBG("ring buffer %s: %lu records written, "
+ "%lu records overrun\n",
+ chan->backend.name,
+ v_read(config, &buf->records_count),
+ v_read(config, &buf->records_overrun));
+ } else {
+ DBG("ring buffer %s, cpu %d: %lu records written, "
+ "%lu records overrun\n",
+ chan->backend.name, cpu,
+ v_read(config, &buf->records_count),
+ v_read(config, &buf->records_overrun));
+
+ if (v_read(config, &buf->records_lost_full)
+ || v_read(config, &buf->records_lost_wrap)
+ || v_read(config, &buf->records_lost_big))
+ 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,
+ v_read(config, &buf->records_lost_full),
+ v_read(config, &buf->records_lost_wrap),
+ v_read(config, &buf->records_lost_big));
+ }
lib_ring_buffer_print_buffer_errors(buf, chan, priv, cpu, handle);
}
- subbuf_trunc((unsigned long)
uatomic_read(&buf->consumed), chan)
>= chan->backend.buf_size)) {
+ unsigned long nr_lost;
+
/*
* We do not overwrite non consumed buffers
* and we are full : record is lost.
*/
+ nr_lost = v_read(config, &buf->records_lost_full);
v_inc(config, &buf->records_lost_full);
- DBG("Record lost: buffer is full\n");
+ if ((nr_lost & (DBG_PRINT_NR_LOST - 1)) == 0) {
+ DBG("%lu or more records lost in (%s:%d) (buffer full)\n",
+ nr_lost + 1, chan->backend.name,
+ buf->backend.cpu);
+ }
return -ENOBUFS;
} else {
/*
*/
}
} else {
+ unsigned long nr_lost;
+
/*
* Next subbuffer reserve offset does not match the
* commit offset. Drop record in producer-consumer and
* overwrite mode. Caused by either a writer OOPS or too
* many nested writes over a reserve/commit pair.
*/
+ nr_lost = v_read(config, &buf->records_lost_wrap);
v_inc(config, &buf->records_lost_wrap);
- DBG("Record lost: buffer wrap-around\n");
+ if ((nr_lost & (DBG_PRINT_NR_LOST - 1)) == 0) {
+ DBG("%lu or more records lost in (%s:%d) (wrap-around)\n",
+ nr_lost + 1, chan->backend.name,
+ buf->backend.cpu);
+ }
return -EIO;
}
offsets->size =
+ ctx->data_size;
if (caa_unlikely(subbuf_offset(offsets->begin, chan)
+ offsets->size > chan->backend.subbuf_size)) {
+ unsigned long nr_lost;
+
/*
* Record too big for subbuffers, report error, don't
* complete the sub-buffer switch.
*/
+ nr_lost = v_read(config, &buf->records_lost_big);
v_inc(config, &buf->records_lost_big);
- DBG("Record lost: record size (%zu bytes) is too large for buffer\n", offsets->size);
+ if ((nr_lost & (DBG_PRINT_NR_LOST - 1)) == 0) {
+ DBG("%lu or more records lost in (%s:%d) record size "
+ " of %zu bytes is too large for buffer\n",
+ nr_lost + 1, chan->backend.name,
+ buf->backend.cpu, offsets->size);
+ }
return -ENOSPC;
} else {
/*
ctx->buf_offset = offsets.begin + offsets.pre_header_padding;
return 0;
}
+
+/*
+ * Force a read (imply TLS fixup for dlopen) of TLS variables.
+ */
+void lttng_fixup_ringbuffer_tls(void)
+{
+ asm volatile ("" : : "m" (lib_ring_buffer_nesting));
+}
projects / lttng-ust.git / blobdiff