X-Git-Url: http://git.lttng.org./?a=blobdiff_plain;f=include%2Flttng%2Fringbuffer-context.h;h=e22fee19943c4bd1c7bff321292a4e16e73ede10;hb=b62f8205216d20d7ef16b536efd81389dc6fdd2f;hp=b335d81a8ed167cc7c19b38c02d6e8e0bc60a940;hpb=aab8b172425eb52f2cd5bd71ce03f8a5624f83df;p=lttng-ust.git diff --git a/include/lttng/ringbuffer-context.h b/include/lttng/ringbuffer-context.h index b335d81a..e22fee19 100644 --- a/include/lttng/ringbuffer-context.h +++ b/include/lttng/ringbuffer-context.h @@ -16,19 +16,18 @@ #include #include -#include +#include #include struct lttng_ust_lib_ring_buffer; struct lttng_ust_lib_ring_buffer_channel; struct lttng_ust_lib_ring_buffer_ctx; -struct lttng_ust_shm_handle; /* * ring buffer context * * Context passed to lib_ring_buffer_reserve(), lib_ring_buffer_commit(), - * lib_ring_buffer_try_discard_reserve(), lib_ring_buffer_align_ctx() and + * lib_ring_buffer_try_discard_reserve(), lttng_ust_lib_ring_buffer_align_ctx() and * lib_ring_buffer_write(). * * IMPORTANT: this structure is part of the ABI between the probe and @@ -40,41 +39,42 @@ struct lttng_ust_shm_handle; * at the end of the structure. */ struct lttng_ust_lib_ring_buffer_ctx { - uint32_t struct_size; /* Size of this structure. */ + uint32_t struct_size; /* Size of this structure. */ - /* input received by lib_ring_buffer_reserve(), saved here. */ + /* input received by lib_ring_buffer_reserve(). */ struct lttng_ust_lib_ring_buffer_channel *chan; /* channel */ - void *priv; /* client private data */ - size_t data_size; /* size of payload */ - int largest_align; /* - * alignment of the largest element - * in the payload - */ + void *priv; /* client private data */ + size_t data_size; /* size of payload */ + int largest_align; /* + * alignment of the largest element + * in the payload + */ /* output from lib_ring_buffer_reserve() */ - int reserve_cpu; /* processor id updated by the 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 - */ - 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 */ + * buffer corresponding to processor id + * for this channel + */ struct lttng_ust_lib_ring_buffer_backend_pages *backend_pages; /* End of base ABI. Fields below should be used after checking struct_size. */ }; /** - * lib_ring_buffer_ctx_init - initialize ring buffer context + * lttng_ust_lib_ring_buffer_ctx_init - initialize ring buffer context * @ctx: ring buffer context to initialize * @chan: channel * @priv: client private data @@ -82,11 +82,11 @@ struct lttng_ust_lib_ring_buffer_ctx { * @largest_align: largest alignment within data payload types */ static inline lttng_ust_notrace -void lib_ring_buffer_ctx_init(struct lttng_ust_lib_ring_buffer_ctx *ctx, +void lttng_ust_lib_ring_buffer_ctx_init(struct lttng_ust_lib_ring_buffer_ctx *ctx, struct lttng_ust_lib_ring_buffer_channel *chan, void *priv, size_t data_size, int largest_align); static inline -void lib_ring_buffer_ctx_init(struct lttng_ust_lib_ring_buffer_ctx *ctx, +void lttng_ust_lib_ring_buffer_ctx_init(struct lttng_ust_lib_ring_buffer_ctx *ctx, struct lttng_ust_lib_ring_buffer_channel *chan, void *priv, size_t data_size, int largest_align) { @@ -101,57 +101,64 @@ void lib_ring_buffer_ctx_init(struct lttng_ust_lib_ring_buffer_ctx *ctx, } /* - * We need to define RING_BUFFER_ALIGN_ATTR so it is known early at + * We need to define LTTNG_UST_RING_BUFFER_ALIGN_ATTR so it is known early at * compile-time. We have to duplicate the "config->align" information and the * definition here because config->align is used both in the slow and fast - * paths, but RING_BUFFER_ALIGN_ATTR is only available for the client code. + * paths, but LTTNG_UST_RING_BUFFER_ALIGN_ATTR is only available for the client + * code. */ -#ifdef RING_BUFFER_ALIGN +#ifdef LTTNG_UST_RING_BUFFER_NATURAL_ALIGN -# define RING_BUFFER_ALIGN_ATTR /* Default arch alignment */ +# define LTTNG_UST_RING_BUFFER_ALIGN_ATTR /* Default arch alignment */ /* - * Calculate the offset needed to align the type. - * size_of_type must be non-zero. + * lttng_ust_lib_ring_buffer_align - Calculate the offset needed to align the type. + * @align_drift: object offset from an "alignment"-aligned address. + * @size_of_type: Must be non-zero, power of 2. */ static inline lttng_ust_notrace -unsigned int lib_ring_buffer_align(size_t align_drift, size_t size_of_type); +unsigned int lttng_ust_lib_ring_buffer_align(size_t align_drift, size_t size_of_type); static inline -unsigned int lib_ring_buffer_align(size_t align_drift, size_t size_of_type) +unsigned int lttng_ust_lib_ring_buffer_align(size_t align_drift, size_t size_of_type) { return lttng_ust_offset_align(align_drift, size_of_type); } #else -# define RING_BUFFER_ALIGN_ATTR __attribute__((packed)) +# define LTTNG_UST_RING_BUFFER_ALIGN_ATTR __attribute__((packed)) /* - * Calculate the offset needed to align the type. - * size_of_type must be non-zero. + * lttng_ust_lib_ring_buffer_align - Calculate the offset needed to align the type. + * @align_drift: object offset from an "alignment"-aligned address. + * @size_of_type: Must be non-zero, power of 2. */ static inline lttng_ust_notrace -unsigned int lib_ring_buffer_align(size_t align_drift, size_t size_of_type); +unsigned int lttng_ust_lib_ring_buffer_align(size_t align_drift, size_t size_of_type); static inline -unsigned int lib_ring_buffer_align(size_t align_drift, size_t size_of_type) +unsigned int lttng_ust_lib_ring_buffer_align(size_t align_drift, size_t size_of_type) { + /* + * On architectures with efficient unaligned memory access, the content + * of the ringbuffer is packed and so the offset is always zero. + */ return 0; } #endif /** - * lib_ring_buffer_align_ctx - Align context offset on "alignment" + * lttng_ust_lib_ring_buffer_align_ctx - Align context offset on "alignment" * @ctx: ring buffer context. */ static inline lttng_ust_notrace -void lib_ring_buffer_align_ctx(struct lttng_ust_lib_ring_buffer_ctx *ctx, +void lttng_ust_lib_ring_buffer_align_ctx(struct lttng_ust_lib_ring_buffer_ctx *ctx, size_t alignment); static inline -void lib_ring_buffer_align_ctx(struct lttng_ust_lib_ring_buffer_ctx *ctx, +void lttng_ust_lib_ring_buffer_align_ctx(struct lttng_ust_lib_ring_buffer_ctx *ctx, size_t alignment) { - ctx->buf_offset += lib_ring_buffer_align(ctx->buf_offset, + ctx->buf_offset += lttng_ust_lib_ring_buffer_align(ctx->buf_offset, alignment); }