X-Git-Url: https://gerrit.fd.io/r/gitweb?a=blobdiff_plain;f=src%2Fsvm%2Fsvm_fifo.h;h=791b513a4a61419088b5aad5048d45649c109486;hb=4744ddbfe0012861895dbd33487569e46b81554b;hp=80e5b0f2d39c23d3e07d46d44627ac82a534d1df;hpb=3e350af5d3e9744a4529a28dd293b2d4601442f7;p=vpp.git diff --git a/src/svm/svm_fifo.h b/src/svm/svm_fifo.h index 80e5b0f2d39..791b513a4a6 100644 --- a/src/svm/svm_fifo.h +++ b/src/svm/svm_fifo.h @@ -23,45 +23,48 @@ #include #include -typedef enum -{ - SVM_FIFO_TAG_NOT_HELD = 0, - SVM_FIFO_TAG_DEQUEUE, - SVM_FIFO_TAG_ENQUEUE, -} svm_lock_tag_t; - /** Out-of-order segment */ typedef struct { u32 next; /**< Next linked-list element pool index */ u32 prev; /**< Previous linked-list element pool index */ - u32 fifo_position; /**< Start of segment, normalized*/ - u32 length; /**< Length of segment */ + u32 start; /**< Start of segment, normalized*/ + u32 length; /**< Length of segment */ } ooo_segment_t; -#define OOO_SEGMENT_INVALID_INDEX ((u32)~0) +format_function_t format_ooo_segment; +format_function_t format_ooo_list; + +#define SVM_FIFO_TRACE (0) +#define OOO_SEGMENT_INVALID_INDEX ((u32)~0) +#define SVM_FIFO_INVALID_SESSION_INDEX ((u32)~0) typedef struct +{ + u32 offset; + u32 len; + u32 action; +} svm_fifo_trace_elem_t; + +typedef struct _svm_fifo { volatile u32 cursize; /**< current fifo size */ u32 nitems; CLIB_CACHE_LINE_ALIGN_MARK (end_cursize); - pthread_mutex_t mutex; /* 8 bytes */ - pthread_cond_t condvar; /* 8 bytes */ - svm_lock_tag_t tag; - - volatile u8 has_event; /**< non-zero if deq event exists */ - u32 owner_pid; + volatile u32 has_event; /**< non-zero if deq event exists */ /* Backpointers */ - u32 server_session_index; + u32 master_session_index; u32 client_session_index; - u8 server_thread_index; + u8 master_thread_index; u8 client_thread_index; + u32 segment_manager; + u32 ct_session_index; /**< Local session index for vpp */ CLIB_CACHE_LINE_ALIGN_MARK (end_shared); u32 head; + volatile u32 want_tx_evt; /**< producer wants nudge */ CLIB_CACHE_LINE_ALIGN_MARK (end_consumer); /* producer */ @@ -70,38 +73,59 @@ typedef struct ooo_segment_t *ooo_segments; /**< Pool of ooo segments */ u32 ooos_list_head; /**< Head of out-of-order linked-list */ u32 ooos_newest; /**< Last segment to have been updated */ - + struct _svm_fifo *next; /**< next in freelist/active chain */ + struct _svm_fifo *prev; /**< prev in active chain */ +#if SVM_FIFO_TRACE + svm_fifo_trace_elem_t *trace; +#endif + u32 freelist_index; /**< aka log2(allocated_size) - const. */ + i8 refcnt; /**< reference count */ CLIB_CACHE_LINE_ALIGN_MARK (data); } svm_fifo_t; -static inline int -svm_fifo_lock (svm_fifo_t * f, u32 pid, u32 tag, int nowait) +typedef enum { - if (PREDICT_TRUE (nowait == 0)) - pthread_mutex_lock (&f->mutex); - else - { - if (pthread_mutex_trylock (&f->mutex)) - return -1; - } - f->owner_pid = pid; - f->tag = tag; - return 0; -} + SVM_FIFO_FULL = -2, +} svm_fifo_err_t; -static inline void -svm_fifo_unlock (svm_fifo_t * f) +typedef struct svm_fifo_segment_ { - f->owner_pid = 0; - f->tag = 0; - CLIB_MEMORY_BARRIER (); - pthread_mutex_unlock (&f->mutex); + u8 *data; + u32 len; +} svm_fifo_segment_t; + +#if SVM_FIFO_TRACE +#define svm_fifo_trace_add(_f, _s, _l, _t) \ +{ \ + svm_fifo_trace_elem_t *trace_elt; \ + vec_add2(_f->trace, trace_elt, 1); \ + trace_elt->offset = _s; \ + trace_elt->len = _l; \ + trace_elt->action = _t; \ } +#else +#define svm_fifo_trace_add(_f, _s, _l, _t) +#endif + +u8 *svm_fifo_dump_trace (u8 * s, svm_fifo_t * f); +u8 *svm_fifo_replay (u8 * s, svm_fifo_t * f, u8 no_read, u8 verbose); static inline u32 svm_fifo_max_dequeue (svm_fifo_t * f) { - return f->cursize; + return clib_atomic_load_acq_n (&f->cursize); +} + +static inline int +svm_fifo_is_full (svm_fifo_t * f) +{ + return (clib_atomic_load_acq_n (&f->cursize) == f->nitems); +} + +static inline int +svm_fifo_is_empty (svm_fifo_t * f) +{ + return (clib_atomic_load_acq_n (&f->cursize) == 0); } static inline u32 @@ -110,6 +134,12 @@ svm_fifo_max_enqueue (svm_fifo_t * f) return f->nitems - svm_fifo_max_dequeue (f); } +static inline int +svm_fifo_has_event (svm_fifo_t * f) +{ + return f->has_event; +} + static inline u8 svm_fifo_has_ooo_data (svm_fifo_t * f) { @@ -119,57 +149,167 @@ svm_fifo_has_ooo_data (svm_fifo_t * f) /** * Sets fifo event flag. * + * Also acts as a release barrier. + * * @return 1 if flag was not set. */ always_inline u8 svm_fifo_set_event (svm_fifo_t * f) { - /* Probably doesn't need to be atomic. Still, better avoid surprises */ - return __sync_lock_test_and_set (&f->has_event, 1) == 0; + /* return __sync_lock_test_and_set (&f->has_event, 1) == 0; + return __sync_bool_compare_and_swap (&f->has_event, 0, 1); */ + return !__atomic_exchange_n (&f->has_event, 1, __ATOMIC_RELEASE); } /** * Unsets fifo event flag. + * + * Also acts as a release barrier. */ always_inline void svm_fifo_unset_event (svm_fifo_t * f) { - /* Probably doesn't need to be atomic. Still, better avoid surprises */ - __sync_lock_test_and_set (&f->has_event, 0); + clib_atomic_release (&f->has_event); } -svm_fifo_t *svm_fifo_create (u32 data_size_in_bytes); +static inline void +svm_fifo_set_want_tx_evt (svm_fifo_t * f, u8 want_evt) +{ + f->want_tx_evt = want_evt; +} + +static inline u8 +svm_fifo_want_tx_evt (svm_fifo_t * f) +{ + return f->want_tx_evt; +} -int svm_fifo_enqueue_nowait (svm_fifo_t * f, int pid, u32 max_bytes, - u8 * copy_from_here); +svm_fifo_t *svm_fifo_create (u32 data_size_in_bytes); +void svm_fifo_free (svm_fifo_t * f); -int svm_fifo_enqueue_with_offset (svm_fifo_t * f, int pid, - u32 offset, u32 required_bytes, - u8 * copy_from_here); +int svm_fifo_enqueue_nowait (svm_fifo_t * f, u32 max_bytes, + const u8 * copy_from_here); +int svm_fifo_enqueue_with_offset (svm_fifo_t * f, u32 offset, + u32 required_bytes, u8 * copy_from_here); +int svm_fifo_dequeue_nowait (svm_fifo_t * f, u32 max_bytes, u8 * copy_here); -int svm_fifo_dequeue_nowait (svm_fifo_t * f, int pid, u32 max_bytes, - u8 * copy_here); +int svm_fifo_peek (svm_fifo_t * f, u32 offset, u32 max_bytes, u8 * copy_here); +int svm_fifo_dequeue_drop (svm_fifo_t * f, u32 max_bytes); +void svm_fifo_dequeue_drop_all (svm_fifo_t * f); +int svm_fifo_segments (svm_fifo_t * f, svm_fifo_segment_t * fs); +void svm_fifo_segments_free (svm_fifo_t * f, svm_fifo_segment_t * fs); +u32 svm_fifo_number_ooo_segments (svm_fifo_t * f); +ooo_segment_t *svm_fifo_first_ooo_segment (svm_fifo_t * f); +void svm_fifo_init_pointers (svm_fifo_t * f, u32 pointer); +void svm_fifo_overwrite_head (svm_fifo_t * f, u8 * data, u32 len); -int svm_fifo_peek (svm_fifo_t * f, int pid, u32 offset, u32 max_bytes, - u8 * copy_here); -int svm_fifo_dequeue_drop (svm_fifo_t * f, int pid, u32 max_bytes); +format_function_t format_svm_fifo; always_inline ooo_segment_t * svm_fifo_newest_ooo_segment (svm_fifo_t * f) { - return f->ooo_segments + f->ooos_newest; + if (f->ooos_newest == OOO_SEGMENT_INVALID_INDEX) + return 0; + return pool_elt_at_index (f->ooo_segments, f->ooos_newest); +} + +always_inline void +svm_fifo_newest_ooo_segment_reset (svm_fifo_t * f) +{ + f->ooos_newest = OOO_SEGMENT_INVALID_INDEX; +} + +/** + * Max contiguous chunk of data that can be read + */ +always_inline u32 +svm_fifo_max_read_chunk (svm_fifo_t * f) +{ + return ((f->tail > f->head) ? (f->tail - f->head) : (f->nitems - f->head)); +} + +/** + * Max contiguous chunk of data that can be written + */ +always_inline u32 +svm_fifo_max_write_chunk (svm_fifo_t * f) +{ + return ((f->tail >= f->head) ? (f->nitems - f->tail) : (f->head - f->tail)); +} + +/** + * Advance tail pointer + * + * Useful for moving tail pointer after external enqueue. + */ +always_inline void +svm_fifo_enqueue_nocopy (svm_fifo_t * f, u32 bytes) +{ + ASSERT (bytes <= svm_fifo_max_enqueue (f)); + f->tail = (f->tail + bytes) % f->nitems; + f->cursize += bytes; +} + +always_inline u8 * +svm_fifo_head (svm_fifo_t * f) +{ + return (f->data + f->head); +} + +always_inline u8 * +svm_fifo_tail (svm_fifo_t * f) +{ + return (f->data + f->tail); +} + +always_inline u32 +ooo_segment_distance_from_tail (svm_fifo_t * f, u32 pos) +{ + /* Ambiguous. Assumption is that ooo segments don't touch tail */ + if (PREDICT_FALSE (pos == f->tail && f->tail == f->head)) + return f->nitems; + + return (((f->nitems + pos) - f->tail) % f->nitems); +} + +always_inline u32 +ooo_segment_distance_to_tail (svm_fifo_t * f, u32 pos) +{ + return (((f->nitems + f->tail) - pos) % f->nitems); } always_inline u32 ooo_segment_offset (svm_fifo_t * f, ooo_segment_t * s) { - return ((f->nitems + s->fifo_position - f->tail) % f->nitems); + return ooo_segment_distance_from_tail (f, s->start); } always_inline u32 ooo_segment_end_offset (svm_fifo_t * f, ooo_segment_t * s) { - return ((f->nitems + s->fifo_position + s->length - f->tail) % f->nitems); + return ooo_segment_distance_from_tail (f, s->start) + s->length; +} + +always_inline u32 +ooo_segment_length (svm_fifo_t * f, ooo_segment_t * s) +{ + return s->length; +} + +always_inline ooo_segment_t * +ooo_segment_get_prev (svm_fifo_t * f, ooo_segment_t * s) +{ + if (s->prev == OOO_SEGMENT_INVALID_INDEX) + return 0; + return pool_elt_at_index (f->ooo_segments, s->prev); +} + +always_inline ooo_segment_t * +ooo_segment_next (svm_fifo_t * f, ooo_segment_t * s) +{ + if (s->next == OOO_SEGMENT_INVALID_INDEX) + return 0; + return pool_elt_at_index (f->ooo_segments, s->next); } #endif /* __included_ssvm_fifo_h__ */