1 // SPDX-License-Identifier: GPL-2.0
4 #include "../kselftest.h"
7 #define PMD_SIZE_FILE_PATH "/sys/kernel/mm/transparent_hugepage/hpage_pmd_size"
8 #define SMAP_FILE_PATH "/proc/self/smaps"
9 #define MAX_LINE_LENGTH 500
11 uint64_t pagemap_get_entry(int fd, char *start)
13 const unsigned long pfn = (unsigned long)start / getpagesize();
17 ret = pread(fd, &entry, sizeof(entry), pfn * sizeof(entry));
18 if (ret != sizeof(entry))
19 ksft_exit_fail_msg("reading pagemap failed\n");
23 bool pagemap_is_softdirty(int fd, char *start)
25 uint64_t entry = pagemap_get_entry(fd, start);
27 // Check if dirty bit (55th bit) is set
28 return entry & 0x0080000000000000ull;
31 bool pagemap_is_swapped(int fd, char *start)
33 uint64_t entry = pagemap_get_entry(fd, start);
35 return entry & 0x4000000000000000ull;
38 bool pagemap_is_populated(int fd, char *start)
40 uint64_t entry = pagemap_get_entry(fd, start);
42 /* Present or swapped. */
43 return entry & 0xc000000000000000ull;
46 unsigned long pagemap_get_pfn(int fd, char *start)
48 uint64_t entry = pagemap_get_entry(fd, start);
50 /* If present (63th bit), PFN is at bit 0 -- 54. */
51 if (entry & 0x8000000000000000ull)
52 return entry & 0x007fffffffffffffull;
56 void clear_softdirty(void)
59 const char *ctrl = "4";
60 int fd = open("/proc/self/clear_refs", O_WRONLY);
63 ksft_exit_fail_msg("opening clear_refs failed\n");
64 ret = write(fd, ctrl, strlen(ctrl));
66 if (ret != strlen(ctrl))
67 ksft_exit_fail_msg("writing clear_refs failed\n");
70 bool check_for_pattern(FILE *fp, const char *pattern, char *buf, size_t len)
72 while (fgets(buf, len, fp)) {
73 if (!strncmp(buf, pattern, strlen(pattern)))
79 uint64_t read_pmd_pagesize(void)
85 fd = open(PMD_SIZE_FILE_PATH, O_RDONLY);
87 ksft_exit_fail_msg("Open hpage_pmd_size failed\n");
89 num_read = read(fd, buf, 19);
92 ksft_exit_fail_msg("Read hpage_pmd_size failed\n");
97 return strtoul(buf, NULL, 10);
100 bool __check_huge(void *addr, char *pattern, int nr_hpages,
106 char buffer[MAX_LINE_LENGTH];
107 char addr_pattern[MAX_LINE_LENGTH];
109 ret = snprintf(addr_pattern, MAX_LINE_LENGTH, "%08lx-",
110 (unsigned long) addr);
111 if (ret >= MAX_LINE_LENGTH)
112 ksft_exit_fail_msg("%s: Pattern is too long\n", __func__);
114 fp = fopen(SMAP_FILE_PATH, "r");
116 ksft_exit_fail_msg("%s: Failed to open file %s\n", __func__, SMAP_FILE_PATH);
118 if (!check_for_pattern(fp, addr_pattern, buffer, sizeof(buffer)))
122 * Fetch the pattern in the same block and check the number of
125 if (!check_for_pattern(fp, pattern, buffer, sizeof(buffer)))
128 snprintf(addr_pattern, MAX_LINE_LENGTH, "%s%%9ld kB", pattern);
130 if (sscanf(buffer, addr_pattern, &thp) != 1)
131 ksft_exit_fail_msg("Reading smap error\n");
135 return thp == (nr_hpages * (hpage_size >> 10));
138 bool check_huge_anon(void *addr, int nr_hpages, uint64_t hpage_size)
140 return __check_huge(addr, "AnonHugePages: ", nr_hpages, hpage_size);
143 bool check_huge_file(void *addr, int nr_hpages, uint64_t hpage_size)
145 return __check_huge(addr, "FilePmdMapped:", nr_hpages, hpage_size);
148 bool check_huge_shmem(void *addr, int nr_hpages, uint64_t hpage_size)
150 return __check_huge(addr, "ShmemPmdMapped:", nr_hpages, hpage_size);