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// SPDX-License-Identifier: GPL-2.0
#include <sys/mman.h>
#include <internal/mmap.h>
#include <internal/lib.h>
#include <linux/kernel.h>
void perf_mmap__init(struct perf_mmap *map, bool overwrite,
libperf_unmap_cb_t unmap_cb)
{
map->fd = -1;
map->overwrite = overwrite;
map->unmap_cb = unmap_cb;
refcount_set(&map->refcnt, 0);
}
size_t perf_mmap__mmap_len(struct perf_mmap *map)
{
return map->mask + 1 + page_size;
}
int perf_mmap__mmap(struct perf_mmap *map, struct perf_mmap_param *mp,
int fd, int cpu)
{
map->prev = 0;
map->mask = mp->mask;
map->base = mmap(NULL, perf_mmap__mmap_len(map), mp->prot,
MAP_SHARED, fd, 0);
if (map->base == MAP_FAILED) {
map->base = NULL;
return -1;
}
map->fd = fd;
map->cpu = cpu;
return 0;
}
void perf_mmap__munmap(struct perf_mmap *map)
{
if (map && map->base != NULL) {
munmap(map->base, perf_mmap__mmap_len(map));
map->base = NULL;
map->fd = -1;
refcount_set(&map->refcnt, 0);
}
if (map && map->unmap_cb)
map->unmap_cb(map);
}
void perf_mmap__get(struct perf_mmap *map)
{
refcount_inc(&map->refcnt);
}
void perf_mmap__put(struct perf_mmap *map)
{
BUG_ON(map->base && refcount_read(&map->refcnt) == 0);
if (refcount_dec_and_test(&map->refcnt))
perf_mmap__munmap(map);
}
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