linux-yocto/tools/testing/selftests/mm/vm_util.h
Alexander Zhu 391e869711 mm: selftest to verify zero-filled pages are mapped to zeropage
When a THP is split, any subpage that is zero-filled will be mapped to the
shared zeropage, hence saving memory.  Add selftest to verify this by
allocating zero-filled THP and comparing RssAnon before and after split.

Link: https://lkml.kernel.org/r/20240830100438.3623486-4-usamaarif642@gmail.com
Signed-off-by: Alexander Zhu <alexlzhu@fb.com>
Signed-off-by: Usama Arif <usamaarif642@gmail.com>
Acked-by: Rik van Riel <riel@surriel.com>
Cc: Barry Song <baohua@kernel.org>
Cc: David Hildenbrand <david@redhat.com>
Cc: Domenico Cerasuolo <cerasuolodomenico@gmail.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Kairui Song <ryncsn@gmail.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Nico Pache <npache@redhat.com>
Cc: Roman Gushchin <roman.gushchin@linux.dev>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Cc: Shakeel Butt <shakeel.butt@linux.dev>
Cc: Shuang Zhai <zhais@google.com>
Cc: Yu Zhao <yuzhao@google.com>
Cc: Shuang Zhai <szhai2@cs.rochester.edu>
Cc: Hugh Dickins <hughd@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-09-09 16:39:03 -07:00

65 lines
2.1 KiB
C

/* SPDX-License-Identifier: GPL-2.0 */
#include <stdint.h>
#include <stdbool.h>
#include <sys/mman.h>
#include <err.h>
#include <strings.h> /* ffsl() */
#include <unistd.h> /* _SC_PAGESIZE */
#define BIT_ULL(nr) (1ULL << (nr))
#define PM_SOFT_DIRTY BIT_ULL(55)
#define PM_MMAP_EXCLUSIVE BIT_ULL(56)
#define PM_UFFD_WP BIT_ULL(57)
#define PM_FILE BIT_ULL(61)
#define PM_SWAP BIT_ULL(62)
#define PM_PRESENT BIT_ULL(63)
extern unsigned int __page_size;
extern unsigned int __page_shift;
static inline unsigned int psize(void)
{
if (!__page_size)
__page_size = sysconf(_SC_PAGESIZE);
return __page_size;
}
static inline unsigned int pshift(void)
{
if (!__page_shift)
__page_shift = (ffsl(psize()) - 1);
return __page_shift;
}
uint64_t pagemap_get_entry(int fd, char *start);
bool pagemap_is_softdirty(int fd, char *start);
bool pagemap_is_swapped(int fd, char *start);
bool pagemap_is_populated(int fd, char *start);
unsigned long pagemap_get_pfn(int fd, char *start);
void clear_softdirty(void);
bool check_for_pattern(FILE *fp, const char *pattern, char *buf, size_t len);
uint64_t read_pmd_pagesize(void);
unsigned long rss_anon(void);
bool check_huge_anon(void *addr, int nr_hpages, uint64_t hpage_size);
bool check_huge_file(void *addr, int nr_hpages, uint64_t hpage_size);
bool check_huge_shmem(void *addr, int nr_hpages, uint64_t hpage_size);
int64_t allocate_transhuge(void *ptr, int pagemap_fd);
unsigned long default_huge_page_size(void);
int detect_hugetlb_page_sizes(size_t sizes[], int max);
int uffd_register(int uffd, void *addr, uint64_t len,
bool miss, bool wp, bool minor);
int uffd_unregister(int uffd, void *addr, uint64_t len);
int uffd_register_with_ioctls(int uffd, void *addr, uint64_t len,
bool miss, bool wp, bool minor, uint64_t *ioctls);
unsigned long get_free_hugepages(void);
/*
* On ppc64 this will only work with radix 2M hugepage size
*/
#define HPAGE_SHIFT 21
#define HPAGE_SIZE (1 << HPAGE_SHIFT)
#define PAGEMAP_PRESENT(ent) (((ent) & (1ull << 63)) != 0)
#define PAGEMAP_PFN(ent) ((ent) & ((1ull << 55) - 1))