-#ifndef _LTTNG_RING_BUFFER_FRONTEND_TYPES_H
-#define _LTTNG_RING_BUFFER_FRONTEND_TYPES_H
-
/*
- * libringbuffer/frontend_types.h
- *
- * Ring Buffer Library Synchronization Header (types).
+ * SPDX-License-Identifier: LGPL-2.1-only
*
* 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
- *
- * Author:
- * Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
+ * Ring Buffer Library Synchronization Header (types).
*
* See ring_buffer_frontend.c for more information on wait-free algorithms.
*/
+#ifndef _LTTNG_RING_BUFFER_FRONTEND_TYPES_H
+#define _LTTNG_RING_BUFFER_FRONTEND_TYPES_H
+
+#include <stdint.h>
#include <string.h>
#include <time.h> /* for timer_t */
#include <urcu/list.h>
#include <urcu/uatomic.h>
-#include <lttng/ringbuffer-config.h>
+#include <lttng/ringbuffer-context.h>
+#include "ringbuffer-config.h"
#include <usterr-signal-safe.h>
#include "backend_types.h"
#include "shm_internal.h"
#include "shm_types.h"
#include "vatomic.h"
+#define LIB_RING_BUFFER_MAX_NESTING 5
+
/*
* A switch is done during tracing or as a final flush after tracing (so it
* won't write in the new sub-buffer).
/* channel: collection of per-cpu ring buffers. */
#define RB_CHANNEL_PADDING 32
-struct channel {
+struct lttng_ust_lib_ring_buffer_channel {
int record_disabled;
unsigned long commit_count_mask; /*
* Commit count mask, removing
int read_timer_enabled;
int finalized; /* Has channel been finalized */
- size_t priv_data_offset;
+ size_t priv_data_offset; /* Offset of private data channel config */
unsigned int nr_streams; /* Number of streams */
struct lttng_ust_shm_handle *handle;
- char padding[RB_CHANNEL_PADDING];
+ /* Extended options. */
+ union {
+ struct {
+ int32_t blocking_timeout_ms;
+ void *priv; /* Private data pointer. */
+ } s;
+ char padding[RB_CHANNEL_PADDING];
+ } u;
/*
* Associated backend contains a variable-length array. Needs to
* be last member.
} __attribute__((aligned(CAA_CACHE_LINE_SIZE)));
/* ring buffer state */
-#define RB_RING_BUFFER_PADDING 64
+#define RB_CRASH_DUMP_ABI_LEN 256
+#define RB_RING_BUFFER_PADDING 60
+
+#define RB_CRASH_DUMP_ABI_MAGIC_LEN 16
+
+/*
+ * The 128-bit magic number is xor'd in the process data so it does not
+ * cause a false positive when searching for buffers by scanning memory.
+ * The actual magic number is:
+ * 0x17, 0x7B, 0xF1, 0x77, 0xBF, 0x17, 0x7B, 0xF1,
+ * 0x77, 0xBF, 0x17, 0x7B, 0xF1, 0x77, 0xBF, 0x17,
+ */
+#define RB_CRASH_DUMP_ABI_MAGIC_XOR \
+ { \
+ 0x17 ^ 0xFF, 0x7B ^ 0xFF, 0xF1 ^ 0xFF, 0x77 ^ 0xFF, \
+ 0xBF ^ 0xFF, 0x17 ^ 0xFF, 0x7B ^ 0xFF, 0xF1 ^ 0xFF, \
+ 0x77 ^ 0xFF, 0xBF ^ 0xFF, 0x17 ^ 0xFF, 0x7B ^ 0xFF, \
+ 0xF1 ^ 0xFF, 0x77 ^ 0xFF, 0xBF ^ 0xFF, 0x17 ^ 0xFF, \
+ }
+
+#define RB_CRASH_ENDIAN 0x1234
+
+#define RB_CRASH_DUMP_ABI_MAJOR 0
+#define RB_CRASH_DUMP_ABI_MINOR 0
+
+enum lttng_crash_type {
+ LTTNG_CRASH_TYPE_UST = 0,
+ LTTNG_CRASH_TYPE_KERNEL = 1,
+};
+
+struct lttng_crash_abi {
+ uint8_t magic[RB_CRASH_DUMP_ABI_MAGIC_LEN];
+ uint64_t mmap_length; /* Overall lenght of crash record */
+ uint16_t endian; /*
+ * { 0x12, 0x34 }: big endian
+ * { 0x34, 0x12 }: little endian
+ */
+ uint16_t major; /* Major number. */
+ uint16_t minor; /* Minor number. */
+ uint8_t word_size; /* Word size (bytes). */
+ uint8_t layout_type; /* enum lttng_crash_type */
+
+ struct {
+ uint32_t prod_offset;
+ uint32_t consumed_offset;
+ uint32_t commit_hot_array;
+ uint32_t commit_hot_seq;
+ uint32_t buf_wsb_array;
+ uint32_t buf_wsb_id;
+ uint32_t sb_array;
+ uint32_t sb_array_shmp_offset;
+ uint32_t sb_backend_p_offset;
+ uint32_t content_size;
+ uint32_t packet_size;
+ } __attribute__((packed)) offset;
+ struct {
+ uint8_t prod_offset;
+ uint8_t consumed_offset;
+ uint8_t commit_hot_seq;
+ uint8_t buf_wsb_id;
+ uint8_t sb_array_shmp_offset;
+ uint8_t sb_backend_p_offset;
+ uint8_t content_size;
+ uint8_t packet_size;
+ } __attribute__((packed)) length;
+ struct {
+ uint32_t commit_hot_array;
+ uint32_t buf_wsb_array;
+ uint32_t sb_array;
+ } __attribute__((packed)) stride;
+
+ uint64_t buf_size; /* Size of the buffer */
+ uint64_t subbuf_size; /* Sub-buffer size */
+ uint64_t num_subbuf; /* Number of sub-buffers for writer */
+ uint32_t mode; /* Buffer mode: 0: overwrite, 1: discard */
+} __attribute__((packed));
+
struct lttng_ust_lib_ring_buffer {
- /* First 32 bytes cache-hot cacheline */
- union v_atomic offset; /* Current offset in the buffer */
+ /* First 32 bytes are for the buffer crash dump ABI */
+ struct lttng_crash_abi crash_abi;
+
+ /* 32 bytes cache-hot cacheline */
+ union v_atomic __attribute__((aligned(32))) offset;
+ /* Current offset in the buffer */
DECLARE_SHMP(struct commit_counters_hot, commit_hot);
/* Commit count per sub-buffer */
long consumed; /*
* standard atomic access (shared)
*/
int record_disabled;
- /* End of first 32 bytes cacheline */
+ /* End of cache-hot 32 bytes cacheline */
+
union v_atomic last_tsc; /*
* Last timestamp written in the buffer.
*/
- struct lttng_ust_lib_ring_buffer_backend backend; /* Associated backend */
+ struct lttng_ust_lib_ring_buffer_backend backend;
+ /* Associated backend */
DECLARE_SHMP(struct commit_counters_cold, commit_cold);
/* Commit count per sub-buffer */
+ DECLARE_SHMP(uint64_t, ts_end); /*
+ * timestamp_end per sub-buffer.
+ * Time is sampled by the
+ * switch_*_end() callbacks
+ * which are the last space
+ * reservation performed in the
+ * sub-buffer before it can be
+ * fully committed and
+ * delivered. This time value is
+ * then read by the deliver
+ * callback, performed by the
+ * last commit before the buffer
+ * becomes readable.
+ */
long active_readers; /*
* Active readers count
* standard atomic access (shared)
char padding[RB_RING_BUFFER_PADDING];
} __attribute__((aligned(CAA_CACHE_LINE_SIZE)));
+/*
+ * ring buffer private context
+ *
+ * Private context passed to lib_ring_buffer_reserve(), lib_ring_buffer_commit(),
+ * lib_ring_buffer_try_discard_reserve(), lttng_ust_lib_ring_buffer_align_ctx() and
+ * lib_ring_buffer_write().
+ *
+ * This context is allocated on an internal shadow-stack by a successful reserve
+ * operation, used by align/write, and freed by commit.
+ */
+
+struct lttng_ust_lib_ring_buffer_ctx_private {
+ /* input received by lib_ring_buffer_reserve(). */
+ struct lttng_ust_lib_ring_buffer_ctx *pub;
+ struct lttng_ust_lib_ring_buffer_channel *chan; /* channel */
+
+ /* output from lib_ring_buffer_reserve() */
+ int reserve_cpu; /* processor id updated by the reserve */
+ size_t slot_size; /* size of the reserved slot */
+ unsigned long buf_offset; /* offset following the record header */
+ unsigned long pre_offset; /*
+ * Initial offset position _before_
+ * the record is written. Positioned
+ * prior to record header alignment
+ * padding.
+ */
+ uint64_t tsc; /* time-stamp counter value */
+ unsigned int rflags; /* reservation flags */
+ void *ip; /* caller ip address */
+
+ struct lttng_ust_lib_ring_buffer *buf; /*
+ * buffer corresponding to processor id
+ * for this channel
+ */
+ struct lttng_ust_lib_ring_buffer_backend_pages *backend_pages;
+};
+
static inline
-void *channel_get_private(struct channel *chan)
+void *channel_get_private_config(struct lttng_ust_lib_ring_buffer_channel *chan)
{
return ((char *) chan) + chan->priv_data_offset;
}
+static inline
+void *channel_get_private(struct lttng_ust_lib_ring_buffer_channel *chan)
+{
+ return chan->u.s.priv;
+}
+
+static inline
+void channel_set_private(struct lttng_ust_lib_ring_buffer_channel *chan, void *priv)
+{
+ chan->u.s.priv = priv;
+}
+
#ifndef __rb_same_type
#define __rb_same_type(a, b) __builtin_types_compatible_p(typeof(a), typeof(b))
#endif
*/
#define CHAN_WARN_ON(c, cond) \
({ \
- struct channel *__chan; \
+ struct lttng_ust_lib_ring_buffer_channel *__chan; \
int _____ret = caa_unlikely(cond); \
if (_____ret) { \
if (__rb_same_type(*(c), struct channel_backend)) \
__chan = caa_container_of((void *) (c), \
- struct channel, \
- backend); \
- else if (__rb_same_type(*(c), struct channel)) \
+ struct lttng_ust_lib_ring_buffer_channel, \
+ backend); \
+ else if (__rb_same_type(*(c), \
+ struct lttng_ust_lib_ring_buffer_channel)) \
__chan = (void *) (c); \
else \
BUG_ON(1); \
_____ret = _____ret; /* For clang "unused result". */ \
})
+/**
+ * lttng_ust_lib_ring_buffer_align_ctx - Align context offset on "alignment"
+ * @ctx: ring buffer context.
+ */
+static inline
+void lttng_ust_lib_ring_buffer_align_ctx(struct lttng_ust_lib_ring_buffer_ctx *ctx,
+ size_t alignment)
+ lttng_ust_notrace;
+static inline
+void lttng_ust_lib_ring_buffer_align_ctx(struct lttng_ust_lib_ring_buffer_ctx *ctx,
+ size_t alignment)
+{
+ struct lttng_ust_lib_ring_buffer_ctx_private *ctx_private = ctx->priv;
+
+ ctx_private->buf_offset += lttng_ust_lib_ring_buffer_align(ctx_private->buf_offset,
+ alignment);
+}
+
#endif /* _LTTNG_RING_BUFFER_FRONTEND_TYPES_H */