X-Git-Url: http://git.lttng.org/?a=blobdiff_plain;f=libringbuffer%2Fbackend_internal.h;h=050c98ac530dfc34f267ff9f23cb9bf8db84bbfd;hb=273973c0f59628f3dc242fdf1a41d5f275b290e2;hp=16d8598525172188aa505627a06932e578b3fe52;hpb=4cfec15c93af7e0cfe3ce769ee90486bb8ab7c37;p=lttng-ust.git diff --git a/libringbuffer/backend_internal.h b/libringbuffer/backend_internal.h index 16d85985..050c98ac 100644 --- a/libringbuffer/backend_internal.h +++ b/libringbuffer/backend_internal.h @@ -1,20 +1,32 @@ -#ifndef _LINUX_RING_BUFFER_BACKEND_INTERNAL_H -#define _LINUX_RING_BUFFER_BACKEND_INTERNAL_H +#ifndef _LTTNG_RING_BUFFER_BACKEND_INTERNAL_H +#define _LTTNG_RING_BUFFER_BACKEND_INTERNAL_H /* - * linux/ringbuffer/backend_internal.h - * - * Copyright (C) 2008-2010 - Mathieu Desnoyers + * libringbuffer/backend_internal.h * * Ring buffer backend (internal helpers). * - * Dual LGPL v2.1/GPL v2 license. + * Copyright (C) 2005-2012 Mathieu Desnoyers + * + * 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 */ #include #include -#include +#include #include "backend_types.h" #include "frontend_types.h" #include "shm.h" @@ -32,7 +44,7 @@ void lib_ring_buffer_backend_free(struct lttng_ust_lib_ring_buffer_backend *bufb int channel_backend_init(struct channel_backend *chanb, const char *name, const struct lttng_ust_lib_ring_buffer_config *config, - void *priv, size_t subbuf_size, + size_t subbuf_size, size_t num_subbuf, struct lttng_ust_shm_handle *handle); void channel_backend_free(struct channel_backend *chanb, struct lttng_ust_shm_handle *handle); @@ -318,7 +330,7 @@ void lib_ring_buffer_clear_noref(const struct lttng_ust_lib_ring_buffer_config * id = CMM_ACCESS_ONCE(shmp_index(handle, bufb->buf_wsb, idx)->id); for (;;) { /* This check is called on the fast path for each record. */ - if (likely(!subbuffer_id_is_noref(config, id))) { + if (caa_likely(!subbuffer_id_is_noref(config, id))) { /* * Store after load dependency ordering the writes to * the subbuffer after load and test of the noref flag @@ -330,7 +342,7 @@ void lib_ring_buffer_clear_noref(const struct lttng_ust_lib_ring_buffer_config * new_id = id; subbuffer_id_clear_noref(config, &new_id); new_id = uatomic_cmpxchg(&shmp_index(handle, bufb->buf_wsb, idx)->id, id, new_id); - if (likely(new_id == id)) + if (caa_likely(new_id == id)) break; id = new_id; } @@ -391,13 +403,13 @@ int update_read_sb_index(const struct lttng_ust_lib_ring_buffer_config *config, * following cmpxchg(). */ old_id = shmp_index(handle, bufb->buf_wsb, consumed_idx)->id; - if (unlikely(!subbuffer_id_is_noref(config, old_id))) + if (caa_unlikely(!subbuffer_id_is_noref(config, old_id))) return -EAGAIN; /* * Make sure the offset count we are expecting matches the one * indicated by the writer. */ - if (unlikely(!subbuffer_id_compare_offset(config, old_id, + if (caa_unlikely(!subbuffer_id_compare_offset(config, old_id, consumed_count))) return -EAGAIN; CHAN_WARN_ON(shmp(handle, bufb->chan), @@ -406,7 +418,7 @@ int update_read_sb_index(const struct lttng_ust_lib_ring_buffer_config *config, consumed_count); new_id = uatomic_cmpxchg(&shmp_index(handle, bufb->buf_wsb, consumed_idx)->id, old_id, bufb->buf_rsb.id); - if (unlikely(old_id != new_id)) + if (caa_unlikely(old_id != new_id)) return -EAGAIN; bufb->buf_rsb.id = new_id; } else { @@ -416,6 +428,10 @@ int update_read_sb_index(const struct lttng_ust_lib_ring_buffer_config *config, return 0; } +#ifndef inline_memcpy +#define inline_memcpy(dest, src, n) memcpy(dest, src, n) +#endif + /* * Use the architecture-specific memcpy implementation for constant-sized * inputs, but rely on an inline memcpy for length statically unknown. @@ -430,4 +446,45 @@ do { \ inline_memcpy(dest, src, __len); \ } while (0) -#endif /* _LINUX_RING_BUFFER_BACKEND_INTERNAL_H */ +/* arch-agnostic implementation */ + +static inline int lttng_ust_fls(unsigned int x) +{ + int r = 32; + + if (!x) + return 0; + if (!(x & 0xFFFF0000U)) { + x <<= 16; + r -= 16; + } + if (!(x & 0xFF000000U)) { + x <<= 8; + r -= 8; + } + if (!(x & 0xF0000000U)) { + x <<= 4; + r -= 4; + } + if (!(x & 0xC0000000U)) { + x <<= 2; + r -= 2; + } + if (!(x & 0x80000000U)) { + x <<= 1; + r -= 1; + } + return r; +} + +static inline int get_count_order(unsigned int count) +{ + int order; + + order = lttng_ust_fls(count) - 1; + if (count & (count - 1)) + order++; + return order; +} + +#endif /* _LTTNG_RING_BUFFER_BACKEND_INTERNAL_H */