numam-dpdk/drivers/event/opdl/opdl_ring.h
John McNamara 8bd5f07c7a doc: fix spelling reported by aspell in comments
Fix spelling errors in the doxygen docs.

Signed-off-by: John McNamara <john.mcnamara@intel.com>
2019-05-03 00:38:14 +02:00

615 lines
19 KiB
C

/* SPDX-License-Identifier: BSD-3-Clause
* Copyright(c) 2017 Intel Corporation
*/
#ifndef _OPDL_H_
#define _OPDL_H_
/**
* @file
* The "opdl_ring" is a data structure that contains a fixed number of slots,
* with each slot having the same, but configurable, size. Entries are input
* into the opdl_ring by copying into available slots. Once in the opdl_ring,
* an entry is processed by a number of stages, with the ordering of stage
* processing controlled by making stages dependent on one or more other stages.
* An entry is not available for a stage to process until it has been processed
* by that stages dependencies. Entries are always made available for
* processing in the same order that they were input in to the opdl_ring.
* Inputting is considered as a stage that depends on all other stages,
* and is also a dependency of all stages.
*
* Inputting and processing in a stage can support multi-threading. Note that
* multi-thread processing can also be done by making stages co-operate e.g. two
* stages where one processes the even packets and the other processes odd
* packets.
*
* A opdl_ring can be used as the basis for pipeline based applications. Instead
* of each stage in a pipeline dequeuing from a ring, processing and enqueuing
* to another ring, it can process entries in-place on the ring. If stages do
* not depend on each other, they can run in parallel.
*
* The opdl_ring works with entries of configurable size, these could be
* pointers to mbufs, pointers to mbufs with application specific meta-data,
* tasks etc.
*/
#include <stdbool.h>
#include <stdint.h>
#include <stdio.h>
#include <rte_eventdev.h>
#ifdef __cplusplus
extern "C" {
#endif
#ifndef OPDL_DISCLAIMS_PER_LCORE
/** Multi-threaded processing allows one thread to process multiple batches in a
* stage, while another thread is processing a single large batch. This number
* controls how many non-contiguous batches one stage can process before being
* blocked by the other stage.
*/
#define OPDL_DISCLAIMS_PER_LCORE 8
#endif
/** Opaque handle to a opdl_ring instance */
struct opdl_ring;
/** Opaque handle to a single stage in a opdl_ring */
struct opdl_stage;
/**
* Create a new instance of a opdl_ring.
*
* @param name
* String containing the name to give the new opdl_ring instance.
* @param num_slots
* How many slots the opdl_ring contains. Must be a power a 2!
* @param slot_size
* How many bytes in each slot.
* @param max_num_stages
* Maximum number of stages.
* @param socket
* The NUMA socket (or SOCKET_ID_ANY) to allocate the memory used for this
* opdl_ring instance.
* @param threadsafe
* Whether to support multiple threads inputting to the opdl_ring or not.
* Enabling this may have a negative impact on performance if only one thread
* will be inputting.
*
* @return
* A pointer to a new opdl_ring instance, or NULL on error.
*/
struct opdl_ring *
opdl_ring_create(const char *name, uint32_t num_slots, uint32_t slot_size,
uint32_t max_num_stages, int socket);
/**
* Get pointer to individual slot in a opdl_ring.
*
* @param t
* The opdl_ring.
* @param index
* Index of slot. If greater than the number of slots it will be masked to be
* within correct range.
*
* @return
* A pointer to that slot.
*/
void *
opdl_ring_get_slot(const struct opdl_ring *t, uint32_t index);
/**
* Get NUMA socket used by a opdl_ring.
*
* @param t
* The opdl_ring.
*
* @return
* NUMA socket.
*/
int
opdl_ring_get_socket(const struct opdl_ring *t);
/**
* Get number of slots in a opdl_ring.
*
* @param t
* The opdl_ring.
*
* @return
* Number of slots.
*/
uint32_t
opdl_ring_get_num_slots(const struct opdl_ring *t);
/**
* Get name of a opdl_ring.
*
* @param t
* The opdl_ring.
*
* @return
* Name string.
*/
const char *
opdl_ring_get_name(const struct opdl_ring *t);
/**
* Adds a new processing stage to a specified opdl_ring instance. Adding a stage
* while there are entries in the opdl_ring being processed will cause undefined
* behaviour.
*
* @param t
* The opdl_ring to add the stage to.
* @param deps
* An array of pointers to other stages that this stage depends on. The other
* stages must be part of the same opdl_ring! Note that input is an implied
* dependency. This can be NULL if num_deps is 0.
* @param num_deps
* The size of the deps array.
* @param threadsafe
* Whether to support multiple threads processing this stage or not.
* Enabling this may have a negative impact on performance if only one thread
* will be processing this stage.
* @param is_input
* Indication to initialise the stage with all slots available or none
*
* @return
* A pointer to the new stage, or NULL on error.
*/
struct opdl_stage *
opdl_stage_add(struct opdl_ring *t, bool threadsafe, bool is_input);
/**
* Returns the input stage of a opdl_ring to be used by other API functions.
*
* @param t
* The opdl_ring.
*
* @return
* A pointer to the input stage.
*/
struct opdl_stage *
opdl_ring_get_input_stage(const struct opdl_ring *t);
/**
* Sets the dependencies for a stage (clears all the previous deps!). Changing
* dependencies while there are entries in the opdl_ring being processed will
* cause undefined behaviour.
*
* @param s
* The stage to set the dependencies for.
* @param deps
* An array of pointers to other stages that this stage will depends on. The
* other stages must be part of the same opdl_ring!
* @param num_deps
* The size of the deps array. This must be > 0.
*
* @return
* 0 on success, a negative value on error.
*/
int
opdl_stage_set_deps(struct opdl_stage *s, struct opdl_stage *deps[],
uint32_t num_deps);
/**
* Returns the opdl_ring that a stage belongs to.
*
* @param s
* The stage
*
* @return
* A pointer to the opdl_ring that the stage belongs to.
*/
struct opdl_ring *
opdl_stage_get_opdl_ring(const struct opdl_stage *s);
/**
* Inputs a new batch of entries into the opdl_ring. This function is only
* threadsafe (with the same opdl_ring parameter) if the threadsafe parameter of
* opdl_ring_create() was true. For performance reasons, this function does not
* check input parameters.
*
* @param t
* The opdl_ring to input entries in to.
* @param entries
* An array of entries that will be copied in to the opdl_ring.
* @param num_entries
* The size of the entries array.
* @param block
* If this is true, the function blocks until enough slots are available to
* input all the requested entries. If false, then the function inputs as
* many entries as currently possible.
*
* @return
* The number of entries successfully input.
*/
uint32_t
opdl_ring_input(struct opdl_ring *t, const void *entries, uint32_t num_entries,
bool block);
/**
* Inputs a new batch of entries into a opdl stage. This function is only
* threadsafe (with the same opdl parameter) if the threadsafe parameter of
* opdl_create() was true. For performance reasons, this function does not
* check input parameters.
*
* @param t
* The opdl ring to input entries in to.
* @param s
* The stage to copy entries to.
* @param entries
* An array of entries that will be copied in to the opdl ring.
* @param num_entries
* The size of the entries array.
* @param block
* If this is true, the function blocks until enough slots are available to
* input all the requested entries. If false, then the function inputs as
* many entries as currently possible.
*
* @return
* The number of entries successfully input.
*/
uint32_t
opdl_ring_copy_from_burst(struct opdl_ring *t, struct opdl_stage *s,
const void *entries, uint32_t num_entries, bool block);
/**
* Copy a batch of entries from the opdl ring. This function is only
* threadsafe (with the same opdl parameter) if the threadsafe parameter of
* opdl_create() was true. For performance reasons, this function does not
* check input parameters.
*
* @param t
* The opdl ring to copy entries from.
* @param s
* The stage to copy entries from.
* @param entries
* An array of entries that will be copied from the opdl ring.
* @param num_entries
* The size of the entries array.
* @param block
* If this is true, the function blocks until enough slots are available to
* input all the requested entries. If false, then the function inputs as
* many entries as currently possible.
*
* @return
* The number of entries successfully input.
*/
uint32_t
opdl_ring_copy_to_burst(struct opdl_ring *t, struct opdl_stage *s,
void *entries, uint32_t num_entries, bool block);
/**
* Before processing a batch of entries, a stage must first claim them to get
* access. This function is threadsafe using same opdl_stage parameter if
* the stage was created with threadsafe set to true, otherwise it is only
* threadsafe with a different opdl_stage per thread. For performance
* reasons, this function does not check input parameters.
*
* @param s
* The opdl_ring stage to read entries in.
* @param entries
* An array of pointers to entries that will be filled in by this function.
* @param num_entries
* The number of entries to attempt to claim for processing (and the size of
* the entries array).
* @param seq
* If not NULL, this is set to the value of the internal stage sequence number
* associated with the first entry returned.
* @param block
* If this is true, the function blocks until num_entries slots are available
* to process. If false, then the function claims as many entries as
* currently possible.
*
* @param atomic
* if this is true, the function will return event according to event flow id
* @return
* The number of pointers to entries filled in to the entries array.
*/
uint32_t
opdl_stage_claim(struct opdl_stage *s, void *entries,
uint32_t num_entries, uint32_t *seq, bool block, bool atomic);
uint32_t
opdl_stage_deps_add(struct opdl_ring *t, struct opdl_stage *s,
uint32_t nb_instance, uint32_t instance_id,
struct opdl_stage *deps[], uint32_t num_deps);
/**
* A function to check how many entries are ready to be claimed.
*
* @param entries
* An array of pointers to entries.
* @param num_entries
* Number of entries in an array.
* @param arg
* An opaque pointer to data passed to the claim function.
* @param block
* When set to true, the function should wait until num_entries are ready to
* be processed. Otherwise it should return immediately.
*
* @return
* Number of entries ready to be claimed.
*/
typedef uint32_t (opdl_ring_check_entries_t)(void *entries[],
uint32_t num_entries, void *arg, bool block);
/**
* Before processing a batch of entries, a stage must first claim them to get
* access. Each entry is checked by the passed check() function and depending
* on block value, it waits until num_entries are ready or returns immediately.
* This function is only threadsafe with a different opdl_stage per thread.
*
* @param s
* The opdl_ring stage to read entries in.
* @param entries
* An array of pointers to entries that will be filled in by this function.
* @param num_entries
* The number of entries to attempt to claim for processing (and the size of
* the entries array).
* @param seq
* If not NULL, this is set to the value of the internal stage sequence number
* associated with the first entry returned.
* @param block
* If this is true, the function blocks until num_entries ready slots are
* available to process. If false, then the function claims as many ready
* entries as currently possible.
* @param check
* Pointer to a function called to check entries.
* @param arg
* Opaque data passed to check() function.
*
* @return
* The number of pointers to ready entries filled in to the entries array.
*/
uint32_t
opdl_stage_claim_check(struct opdl_stage *s, void **entries,
uint32_t num_entries, uint32_t *seq, bool block,
opdl_ring_check_entries_t *check, void *arg);
/**
* Before processing a batch of entries, a stage must first claim them to get
* access. This function is threadsafe using same opdl_stage parameter if
* the stage was created with threadsafe set to true, otherwise it is only
* threadsafe with a different opdl_stage per thread.
*
* The difference between this function and opdl_stage_claim() is that this
* function copies the entries from the opdl_ring. Note that any changes made to
* the copied entries will not be reflected back in to the entries in the
* opdl_ring, so this function probably only makes sense if the entries are
* pointers to other data. For performance reasons, this function does not check
* input parameters.
*
* @param s
* The opdl_ring stage to read entries in.
* @param entries
* An array of entries that will be filled in by this function.
* @param num_entries
* The number of entries to attempt to claim for processing (and the size of
* the entries array).
* @param seq
* If not NULL, this is set to the value of the internal stage sequence number
* associated with the first entry returned.
* @param block
* If this is true, the function blocks until num_entries slots are available
* to process. If false, then the function claims as many entries as
* currently possible.
*
* @return
* The number of entries copied in to the entries array.
*/
uint32_t
opdl_stage_claim_copy(struct opdl_stage *s, void *entries,
uint32_t num_entries, uint32_t *seq, bool block);
/**
* This function must be called when a stage has finished its processing of
* entries, to make them available to any dependent stages. All entries that are
* claimed by the calling thread in the stage will be disclaimed. It is possible
* to claim multiple batches before disclaiming. For performance reasons, this
* function does not check input parameters.
*
* @param s
* The opdl_ring stage in which to disclaim all claimed entries.
*
* @param block
* Entries are always made available to a stage in the same order that they
* were input in the stage. If a stage is multithread safe, this may mean that
* full disclaiming of a batch of entries can not be considered complete until
* all earlier threads in the stage have disclaimed. If this parameter is true
* then the function blocks until all entries are fully disclaimed, otherwise
* it disclaims as many as currently possible, with non fully disclaimed
* batches stored until the next call to a claim or disclaim function for this
* stage on this thread.
*
* If a thread is not going to process any more entries in this stage, it
* *must* first call this function with this parameter set to true to ensure
* it does not block the entire opdl_ring.
*
* In a single threaded stage, this parameter has no effect.
*/
int
opdl_stage_disclaim(struct opdl_stage *s, uint32_t num_entries,
bool block);
/**
* This function can be called when a stage has finished its processing of
* entries, to make them available to any dependent stages. The difference
* between this function and opdl_stage_disclaim() is that here only a
* portion of entries are disclaimed, not all of them. For performance reasons,
* this function does not check input parameters.
*
* @param s
* The opdl_ring stage in which to disclaim entries.
*
* @param num_entries
* The number of entries to disclaim.
*
* @param block
* Entries are always made available to a stage in the same order that they
* were input in the stage. If a stage is multithread safe, this may mean that
* full disclaiming of a batch of entries can not be considered complete until
* all earlier threads in the stage have disclaimed. If this parameter is true
* then the function blocks until the specified number of entries has been
* disclaimed (or there are no more entries to disclaim). Otherwise it
* disclaims as many claims as currently possible and an attempt to disclaim
* them is made the next time a claim or disclaim function for this stage on
* this thread is called.
*
* In a single threaded stage, this parameter has no effect.
*/
void
opdl_stage_disclaim_n(struct opdl_stage *s, uint32_t num_entries,
bool block);
/**
* Check how many entries can be input.
*
* @param t
* The opdl_ring instance to check.
*
* @return
* The number of new entries currently allowed to be input.
*/
uint32_t
opdl_ring_available(struct opdl_ring *t);
/**
* Check how many entries can be processed in a stage.
*
* @param s
* The stage to check.
*
* @return
* The number of entries currently available to be processed in this stage.
*/
uint32_t
opdl_stage_available(struct opdl_stage *s);
/**
* Check how many entries are available to be processed.
*
* NOTE : DOES NOT CHANGE ANY STATE WITHIN THE STAGE
*
* @param s
* The stage to check.
*
* @param num_entries
* The number of entries to check for availability.
*
* @return
* The number of entries currently available to be processed in this stage.
*/
uint32_t
opdl_stage_find_num_available(struct opdl_stage *s, uint32_t num_entries);
/**
* Create empty stage instance and return the pointer.
*
* @param t
* The pointer of opdl_ring.
*
* @param threadsafe
* enable multiple thread or not.
* @return
* The pointer of one empty stage instance.
*/
struct opdl_stage *
opdl_stage_create(struct opdl_ring *t, bool threadsafe);
/**
* Set the internal queue id for each stage instance.
*
* @param s
* The pointer of stage instance.
*
* @param queue_id
* The value of internal queue id.
*/
void
opdl_stage_set_queue_id(struct opdl_stage *s,
uint32_t queue_id);
/**
* Prints information on opdl_ring instance and all its stages
*
* @param t
* The stage to print info on.
* @param f
* Where to print the info.
*/
void
opdl_ring_dump(const struct opdl_ring *t, FILE *f);
/**
* Blocks until all entries in a opdl_ring have been processed by all stages.
*
* @param t
* The opdl_ring instance to flush.
*/
void
opdl_ring_flush(struct opdl_ring *t);
/**
* Deallocates all resources used by a opdl_ring instance
*
* @param t
* The opdl_ring instance to free.
*/
void
opdl_ring_free(struct opdl_ring *t);
/**
* Search for a opdl_ring by its name
*
* @param name
* The name of the opdl_ring.
* @return
* The pointer to the opdl_ring matching the name, or NULL if not found.
*
*/
struct opdl_ring *
opdl_ring_lookup(const char *name);
/**
* Set a opdl_stage to threadsafe variable.
*
* @param s
* The opdl_stage.
* @param threadsafe
* Threadsafe value.
*/
void
opdl_ring_set_stage_threadsafe(struct opdl_stage *s, bool threadsafe);
/**
* Compare the event descriptor with original version in the ring.
* if key field event descriptor is changed by application, then
* update the slot in the ring otherwise do nothing with it.
* the key field is flow_id, priority, mbuf, impl_opaque
*
* @param s
* The opdl_stage.
* @param ev
* pointer of the event descriptor.
* @param index
* index of the event descriptor.
* @param atomic
* queue type associate with the stage.
* @return
* if the event key field is changed compare with previous record.
*/
bool
opdl_ring_cas_slot(struct opdl_stage *s, const struct rte_event *ev,
uint32_t index, bool atomic);
#ifdef __cplusplus
}
#endif
#endif /* _OPDL_H_ */