mirror of
https://github.com/AuxXxilium/linux_dsm_epyc7002.git
synced 2024-12-25 07:43:57 +07:00
25763b3c86
Based on 1 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of version 2 of the gnu general public license as published by the free software foundation extracted by the scancode license scanner the SPDX license identifier GPL-2.0-only has been chosen to replace the boilerplate/reference in 107 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Allison Randal <allison@lohutok.net> Reviewed-by: Richard Fontana <rfontana@redhat.com> Reviewed-by: Steve Winslow <swinslow@gmail.com> Reviewed-by: Alexios Zavras <alexios.zavras@intel.com> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190528171438.615055994@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
119 lines
2.5 KiB
C
119 lines
2.5 KiB
C
// SPDX-License-Identifier: GPL-2.0-only
|
|
/* Copyright (c) 2016 Facebook
|
|
*/
|
|
#include "percpu_freelist.h"
|
|
|
|
int pcpu_freelist_init(struct pcpu_freelist *s)
|
|
{
|
|
int cpu;
|
|
|
|
s->freelist = alloc_percpu(struct pcpu_freelist_head);
|
|
if (!s->freelist)
|
|
return -ENOMEM;
|
|
|
|
for_each_possible_cpu(cpu) {
|
|
struct pcpu_freelist_head *head = per_cpu_ptr(s->freelist, cpu);
|
|
|
|
raw_spin_lock_init(&head->lock);
|
|
head->first = NULL;
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
void pcpu_freelist_destroy(struct pcpu_freelist *s)
|
|
{
|
|
free_percpu(s->freelist);
|
|
}
|
|
|
|
static inline void ___pcpu_freelist_push(struct pcpu_freelist_head *head,
|
|
struct pcpu_freelist_node *node)
|
|
{
|
|
raw_spin_lock(&head->lock);
|
|
node->next = head->first;
|
|
head->first = node;
|
|
raw_spin_unlock(&head->lock);
|
|
}
|
|
|
|
void __pcpu_freelist_push(struct pcpu_freelist *s,
|
|
struct pcpu_freelist_node *node)
|
|
{
|
|
struct pcpu_freelist_head *head = this_cpu_ptr(s->freelist);
|
|
|
|
___pcpu_freelist_push(head, node);
|
|
}
|
|
|
|
void pcpu_freelist_push(struct pcpu_freelist *s,
|
|
struct pcpu_freelist_node *node)
|
|
{
|
|
unsigned long flags;
|
|
|
|
local_irq_save(flags);
|
|
__pcpu_freelist_push(s, node);
|
|
local_irq_restore(flags);
|
|
}
|
|
|
|
void pcpu_freelist_populate(struct pcpu_freelist *s, void *buf, u32 elem_size,
|
|
u32 nr_elems)
|
|
{
|
|
struct pcpu_freelist_head *head;
|
|
unsigned long flags;
|
|
int i, cpu, pcpu_entries;
|
|
|
|
pcpu_entries = nr_elems / num_possible_cpus() + 1;
|
|
i = 0;
|
|
|
|
/* disable irq to workaround lockdep false positive
|
|
* in bpf usage pcpu_freelist_populate() will never race
|
|
* with pcpu_freelist_push()
|
|
*/
|
|
local_irq_save(flags);
|
|
for_each_possible_cpu(cpu) {
|
|
again:
|
|
head = per_cpu_ptr(s->freelist, cpu);
|
|
___pcpu_freelist_push(head, buf);
|
|
i++;
|
|
buf += elem_size;
|
|
if (i == nr_elems)
|
|
break;
|
|
if (i % pcpu_entries)
|
|
goto again;
|
|
}
|
|
local_irq_restore(flags);
|
|
}
|
|
|
|
struct pcpu_freelist_node *__pcpu_freelist_pop(struct pcpu_freelist *s)
|
|
{
|
|
struct pcpu_freelist_head *head;
|
|
struct pcpu_freelist_node *node;
|
|
int orig_cpu, cpu;
|
|
|
|
orig_cpu = cpu = raw_smp_processor_id();
|
|
while (1) {
|
|
head = per_cpu_ptr(s->freelist, cpu);
|
|
raw_spin_lock(&head->lock);
|
|
node = head->first;
|
|
if (node) {
|
|
head->first = node->next;
|
|
raw_spin_unlock(&head->lock);
|
|
return node;
|
|
}
|
|
raw_spin_unlock(&head->lock);
|
|
cpu = cpumask_next(cpu, cpu_possible_mask);
|
|
if (cpu >= nr_cpu_ids)
|
|
cpu = 0;
|
|
if (cpu == orig_cpu)
|
|
return NULL;
|
|
}
|
|
}
|
|
|
|
struct pcpu_freelist_node *pcpu_freelist_pop(struct pcpu_freelist *s)
|
|
{
|
|
struct pcpu_freelist_node *ret;
|
|
unsigned long flags;
|
|
|
|
local_irq_save(flags);
|
|
ret = __pcpu_freelist_pop(s);
|
|
local_irq_restore(flags);
|
|
return ret;
|
|
}
|