/* * Copyright (c) 2013-2019, Intel Corporation * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions are met: * * * Redistributions of source code must retain the above copyright notice, * this list of conditions and the following disclaimer. * * Redistributions in binary form must reproduce the above copyright notice, * this list of conditions and the following disclaimer in the documentation * and/or other materials provided with the distribution. * * Neither the name of Intel Corporation nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE * POSSIBILITY OF SUCH DAMAGE. */ #ifndef PT_EVENT_QUEUE_H #define PT_EVENT_QUEUE_H #include "intel-pt.h" #include /* Events are grouped by the packet the event binds to. */ enum pt_event_binding { evb_psbend, evb_tip, evb_fup, evb_max }; enum { /* The maximal number of pending events - should be a power of two. */ evq_max = 8 }; /* A queue of events. */ struct pt_event_queue { /* A collection of event queues, one per binding. */ struct pt_event queue[evb_max][evq_max]; /* The begin and end indices for the above event queues. */ uint8_t begin[evb_max]; uint8_t end[evb_max]; /* A standalone event to be published immediately. */ struct pt_event standalone; }; /* Initialize (or reset) an event queue. */ extern void pt_evq_init(struct pt_event_queue *); /* Get a standalone event. * * Returns a pointer to the standalone event on success. * Returns NULL if @evq is NULL. */ extern struct pt_event *pt_evq_standalone(struct pt_event_queue *evq); /* Enqueue an event. * * Adds a new event to @evq for binding @evb. * * Returns a pointer to the new event on success. * Returns NULL if @evq is NULL or @evb is invalid. * Returns NULL if @evq is full. */ extern struct pt_event *pt_evq_enqueue(struct pt_event_queue *evq, enum pt_event_binding evb); /* Dequeue an event. * * Removes the first event for binding @evb from @evq. * * Returns a pointer to the dequeued event on success. * Returns NULL if @evq is NULL or @evb is invalid. * Returns NULL if @evq is empty. */ extern struct pt_event *pt_evq_dequeue(struct pt_event_queue *evq, enum pt_event_binding evb); /* Clear a queue and discard events. * * Removes all events for binding @evb from @evq. * * Returns zero on success, a negative error code otherwise. * Returns -pte_internal if @evq is NULL or @evb is invalid. */ extern int pt_evq_clear(struct pt_event_queue *evq, enum pt_event_binding evb); /* Check for emptiness. * * Check if @evq for binding @evb is empty. * * Returns a positive number if @evq is empty. * Returns zero if @evq is not empty. * Returns -pte_internal if @evq is NULL or @evb is invalid. */ extern int pt_evq_empty(const struct pt_event_queue *evq, enum pt_event_binding evb); /* Check for non-emptiness. * * Check if @evq for binding @evb contains pending events. * * Returns a positive number if @evq is not empty. * Returns zero if @evq is empty. * Returns -pte_internal if @evq is NULL or @evb is invalid. */ extern int pt_evq_pending(const struct pt_event_queue *evq, enum pt_event_binding evb); /* Find an event by type. * * Searches @evq for binding @evb for an event of type @evt. * * Returns a pointer to the first matching event on success. * Returns NULL if there is no such event. * Returns NULL if @evq is NULL. * Returns NULL if @evb or @evt is invalid. */ extern struct pt_event *pt_evq_find(struct pt_event_queue *evq, enum pt_event_binding evb, enum pt_event_type evt); #endif /* PT_EVENT_QUEUE_H */