kernel/include/kernel/percpu.h

// Copyright 2017 The Fuchsia Authors
//
// Use of this source code is governed by a MIT-style
// license that can be found in the LICENSE file or at
// https://opensource.org/licenses/MIT
#pragma once

#include <arch/ops.h>
#include <kernel/align.h>
#include <kernel/event.h>
#include <kernel/fair_scheduler.h>
#include <kernel/stats.h>
#include <kernel/thread.h>
#include <kernel/timer.h>
#include <list.h>
#include <sys/types.h>
#include <zircon/compiler.h>

__BEGIN_CDECLS

struct percpu {
    // per cpu timer queue
    struct list_node timer_queue;

    // per cpu preemption timer; ZX_TIME_INFINITE means not set
    zx_time_t preempt_timer_deadline;

    // deadline of this cpu's platform timer or ZX_TIME_INFINITE if not set
    zx_time_t next_timer_deadline;

    // per cpu run queue and bitmap to indicate which queues are non empty
    struct list_node run_queue[NUM_PRIORITIES];
    uint32_t run_queue_bitmap;

#if WITH_FAIR_SCHEDULER
    FairScheduler fair_runqueue;
#endif

#if WITH_LOCK_DEP
    // state for runtime lock validation when in irq context
    lockdep_state_t lock_state;
#endif

    // thread/cpu level statistics
    struct cpu_stats stats;

    // per cpu idle thread
    thread_t idle_thread;

    // kernel counters arena
    int64_t* counters;

    // dpc context
    list_node_t dpc_list;
    event_t dpc_event;
    // request the dpc thread to stop by setting to true; guarded by dpc_lock
    bool dpc_stop;
    // each cpu has a dedicated thread for processing dpcs
    thread_t* dpc_thread;
} __CPU_ALIGN;

// the kernel per-cpu structure
extern struct percpu percpu[SMP_MAX_CPUS];

// make sure the bitmap is large enough to cover our number of priorities
static_assert(NUM_PRIORITIES <= sizeof(percpu[0].run_queue_bitmap) * CHAR_BIT, "");

static inline struct percpu* get_local_percpu(void) {
    return &percpu[arch_curr_cpu_num()];
}

__END_CDECLS