onvm_threading.h

/*********************************************************************
 *                     openNetVM
 *              https://sdnfv.github.io
 *
 *   BSD LICENSE
 *
 *   Copyright(c)
 *            2015-2019 George Washington University
 *            2015-2019 University of California Riverside
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 *
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 *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
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 *   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 *   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
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 *
 * onvm_threading.h - threading helper functions
 ********************************************************************/

#ifndef _ONVM_THREADING_H_
#define _ONVM_THREADING_H_

#include "onvm_common.h"

/********************************Global variables*****************************/

extern struct onvm_nf *nfs;

/********************************Interfaces***********************************/

/**
 * Gets the total number of cores.
 */
int
onvm_threading_get_num_cores(void);

/**
 * Get the core id for a new NF to run on.
 * If no flags are passed finds the core with the least number of NFs running on it,
 * will reserve the core unless the share core flag is set
 * For manual core assignment: the user picks the core
 * For shared core will allow other NFs to share assigned core
 *
 * @param core_value
 *    A pointer to set the core for NF to run on
 *    if manual core mode is used, a preferred core id is accessed from this pointer
 * @param flags
 *    Flags is a bitmask for specific core assignment options
 *    Bit MANUAL_CORE_ASSIGNMENT_BIT: for manually choosing a core by the user
 *    Bit SHARE_CORE_BIT: allow other NFs(also with SHARE_CORE_BIT enabled) to start on assigned core
 * @param cores
 *    A pointer to the core_status map containing core information
 *
 * @return
 *    0 on success
 *    NF_NO_CORES or NF_NO_DEDICATED_CORES or NF_CORE_OUT_OF_RANGE or NF_CORE_BUSY on error
 */
int
onvm_threading_get_core(uint16_t *core_value, uint8_t flags, struct core_status *cores);

/**
 * Uses the dpdk function to reaffinitize the calling pthread to another core.
 *
 * @param info
 *    An integer core value to bind the pthread to
 * @return
 *    0 on success, or a negative value on failure
 */
int
onvm_threading_core_affinitize(int core);

/**
 * Based on current core usage decides if any NF should be moved to passed candidate core.
 *
 * @param candidate_core
 *    An integer core value to possibly move a NF to
 * @param cores
 *    A pointer to the core_status map containing core information
 *
 * @return
 *    An instance ID of a candidate NF that should be moved to candidate_core
 */
int
onvm_threading_find_nf_to_reassign_core(uint16_t candidate_core, struct core_status *cores);

#endif  // _ONVM_THREADING_H_