X-Git-Url: http://git.lttng.org./?a=blobdiff_plain;f=libringbuffer%2Fbackend_internal.h;h=c9ed81be0e5b5c559ba8de23846a6052ecc8ddea;hb=bfd265823dd6c3b272b92c6e39456e851bfd51ce;hp=16d8598525172188aa505627a06932e578b3fe52;hpb=4cfec15c93af7e0cfe3ce769ee90486bb8ab7c37;p=lttng-ust.git diff --git a/libringbuffer/backend_internal.h b/libringbuffer/backend_internal.h index 16d85985..c9ed81be 100644 --- a/libringbuffer/backend_internal.h +++ b/libringbuffer/backend_internal.h @@ -14,7 +14,7 @@ #include #include -#include +#include #include "backend_types.h" #include "frontend_types.h" #include "shm.h" @@ -32,7 +32,7 @@ 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 +318,7 @@ 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 +330,7 @@ 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 +391,13 @@ 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 +406,7 @@ 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 +416,10 @@ 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 +434,61 @@ do { \ inline_memcpy(dest, src, __len); \ } while (0) +/* 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; +} + +static inline +unsigned int hweight32(unsigned int value) +{ + unsigned int r; + + r = value; + r = r - ((r >> 1) & 0x55555555); + r = (r & 0x33333333) + ((r >> 2) & 0x33333333); + r += r >> 4; + r &= 0x0F0F0F0F; + r += r >> 8; + r += r >> 16; + r &= 0x000000FF; + return r; +} + #endif /* _LINUX_RING_BUFFER_BACKEND_INTERNAL_H */