X-Git-Url: https://gerrit.fd.io/r/gitweb?a=blobdiff_plain;f=src%2Fsvm%2Fsvm_fifo.h;h=4a119341d8b3cb3a519e360c4ab6c56331e86e26;hb=c5df8c71c;hp=f32ef41da7da78477edeab38cc78a67866667417;hpb=f03a59ab008908f98fd7d1b187a8c0fb78b01add;p=vpp.git diff --git a/src/svm/svm_fifo.h b/src/svm/svm_fifo.h index f32ef41da7d..4a119341d8b 100644 --- a/src/svm/svm_fifo.h +++ b/src/svm/svm_fifo.h @@ -1,5 +1,5 @@ /* - * Copyright (c) 2016 Cisco and/or its affiliates. + * Copyright (c) 2016-2019 Cisco and/or its affiliates. * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at: @@ -36,27 +36,51 @@ typedef struct format_function_t format_ooo_segment; format_function_t format_ooo_list; -#define OOO_SEGMENT_INVALID_INDEX ((u32)~0) +#define SVM_FIFO_TRACE (0) +#define OOO_SEGMENT_INVALID_INDEX ((u32)~0) +#define SVM_FIFO_INVALID_SESSION_INDEX ((u32)~0) +#define SVM_FIFO_INVALID_INDEX ((u32)~0) +#define SVM_FIFO_MAX_EVT_SUBSCRIBERS 8 + +enum +{ + SVM_FIFO_NO_TX_NOTIF = 0, + SVM_FIFO_WANT_TX_NOTIF = 1, + SVM_FIFO_WANT_TX_NOTIF_IF_FULL = 2, +}; + +typedef struct +{ + u32 offset; + u32 len; + u32 action; +} svm_fifo_trace_elem_t; typedef struct _svm_fifo { + CLIB_CACHE_LINE_ALIGN_MARK (shared_first); volatile u32 cursize; /**< current fifo size */ u32 nitems; - CLIB_CACHE_LINE_ALIGN_MARK (end_cursize); + CLIB_CACHE_LINE_ALIGN_MARK (shared_second); volatile u32 has_event; /**< non-zero if deq event exists */ - /* Backpointers */ u32 master_session_index; u32 client_session_index; u8 master_thread_index; u8 client_thread_index; u32 segment_manager; - CLIB_CACHE_LINE_ALIGN_MARK (end_shared); + u32 segment_index; + u32 ct_session_index; /**< Local session index for vpp */ + u32 freelist_index; /**< aka log2(allocated_size) - const. */ + i8 refcnt; /**< reference count */ + + CLIB_CACHE_LINE_ALIGN_MARK (consumer); u32 head; - CLIB_CACHE_LINE_ALIGN_MARK (end_consumer); + volatile u32 want_tx_ntf; /**< producer wants nudge */ + volatile u32 has_tx_ntf; - /* producer */ + CLIB_CACHE_LINE_ALIGN_MARK (producer); u32 tail; ooo_segment_t *ooo_segments; /**< Pool of ooo segments */ @@ -64,13 +88,59 @@ typedef struct _svm_fifo 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 */ + volatile u8 n_subscribers; + u8 subscribers[SVM_FIFO_MAX_EVT_SUBSCRIBERS]; + +#if SVM_FIFO_TRACE + svm_fifo_trace_elem_t *trace; +#endif + CLIB_CACHE_LINE_ALIGN_MARK (data); } svm_fifo_t; +typedef enum +{ + SVM_FIFO_FULL = -2, +} svm_fifo_err_t; + +typedef struct svm_fifo_segment_ +{ + 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 @@ -79,6 +149,12 @@ 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) { @@ -88,42 +164,155 @@ 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 !clib_atomic_swap_rel_n (&f->has_event, 1); } /** * Unsets fifo event flag. + * + * Also acts as an acquire 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_release (&f->has_event); + clib_atomic_swap_acq_n (&f->has_event, 0); } svm_fifo_t *svm_fifo_create (u32 data_size_in_bytes); void svm_fifo_free (svm_fifo_t * f); int svm_fifo_enqueue_nowait (svm_fifo_t * f, u32 max_bytes, - u8 * copy_from_here); + 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_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); -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_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); void svm_fifo_init_pointers (svm_fifo_t * f, u32 pointer); - +void svm_fifo_overwrite_head (svm_fifo_t * f, u8 * data, u32 len); +void svm_fifo_add_subscriber (svm_fifo_t * f, u8 subscriber); +void svm_fifo_del_subscriber (svm_fifo_t * f, u8 subscriber); format_function_t format_svm_fifo; +/** + * 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; + clib_atomic_fetch_add_rel (&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 +svm_fifo_nitems (svm_fifo_t * f) +{ + return f->nitems; +} + +static inline void +svm_fifo_add_want_tx_ntf (svm_fifo_t * f, u8 ntf_type) +{ + f->want_tx_ntf |= ntf_type; +} + +static inline void +svm_fifo_del_want_tx_ntf (svm_fifo_t * f, u8 ntf_type) +{ + f->want_tx_ntf &= ~ntf_type; +} + +static inline void +svm_fifo_clear_tx_ntf (svm_fifo_t * f) +{ + /* Set the flag if want_tx_notif_if_full was the only ntf requested */ + f->has_tx_ntf = f->want_tx_ntf == SVM_FIFO_WANT_TX_NOTIF_IF_FULL; + svm_fifo_del_want_tx_ntf (f, SVM_FIFO_WANT_TX_NOTIF); +} + +static inline void +svm_fifo_reset_tx_ntf (svm_fifo_t * f) +{ + f->has_tx_ntf = 0; +} + +static inline u8 +svm_fifo_needs_tx_ntf (svm_fifo_t * f, u32 n_last_deq) +{ + u8 want_ntf = f->want_tx_ntf; + + if (PREDICT_TRUE (want_ntf == SVM_FIFO_NO_TX_NOTIF)) + return 0; + else if (want_ntf & SVM_FIFO_WANT_TX_NOTIF) + return 1; + else if (want_ntf & SVM_FIFO_WANT_TX_NOTIF_IF_FULL) + { + u32 max_deq = svm_fifo_max_dequeue (f); + u32 nitems = svm_fifo_nitems (f); + if (!f->has_tx_ntf && max_deq < nitems + && max_deq + n_last_deq >= nitems) + return 1; + + return 0; + } + return 0; +} + +always_inline u8 +svm_fifo_n_subscribers (svm_fifo_t * f) +{ + return f->n_subscribers; +} + +u32 svm_fifo_number_ooo_segments (svm_fifo_t * f); +ooo_segment_t *svm_fifo_first_ooo_segment (svm_fifo_t * f); + always_inline ooo_segment_t * svm_fifo_newest_ooo_segment (svm_fifo_t * f) { @@ -132,26 +321,38 @@ svm_fifo_newest_ooo_segment (svm_fifo_t * f) 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; +} + always_inline u32 -ooo_segment_distance_to_tail (svm_fifo_t * f, u32 a) +ooo_segment_distance_from_tail (svm_fifo_t * f, u32 pos) { /* Ambiguous. Assumption is that ooo segments don't touch tail */ - if (a == f->tail && f->tail == f->head) + if (PREDICT_FALSE (pos == f->tail && f->tail == f->head)) return f->nitems; - return ((f->nitems + a - f->tail) % 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 ooo_segment_distance_to_tail (f, s->start); + 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 ooo_segment_distance_to_tail (f, s->start) + s->length; + return ooo_segment_distance_from_tail (f, s->start) + s->length; } always_inline u32 @@ -168,6 +369,14 @@ ooo_segment_get_prev (svm_fifo_t * f, ooo_segment_t * s) 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__ */ /*