2 * page-types: Tool for querying page flags
4 * Copyright (C) 2009 Intel corporation
6 * Authors: Wu Fengguang <fengguang.wu@intel.com>
8 * Released under the General Public License (GPL).
11 #define _LARGEFILE64_SOURCE
21 #include <sys/types.h>
22 #include <sys/errno.h>
23 #include <sys/fcntl.h>
27 * pagemap kernel ABI bits
30 #define PM_ENTRY_BYTES sizeof(uint64_t)
31 #define PM_STATUS_BITS 3
32 #define PM_STATUS_OFFSET (64 - PM_STATUS_BITS)
33 #define PM_STATUS_MASK (((1LL << PM_STATUS_BITS) - 1) << PM_STATUS_OFFSET)
34 #define PM_STATUS(nr) (((nr) << PM_STATUS_OFFSET) & PM_STATUS_MASK)
35 #define PM_PSHIFT_BITS 6
36 #define PM_PSHIFT_OFFSET (PM_STATUS_OFFSET - PM_PSHIFT_BITS)
37 #define PM_PSHIFT_MASK (((1LL << PM_PSHIFT_BITS) - 1) << PM_PSHIFT_OFFSET)
38 #define PM_PSHIFT(x) (((u64) (x) << PM_PSHIFT_OFFSET) & PM_PSHIFT_MASK)
39 #define PM_PFRAME_MASK ((1LL << PM_PSHIFT_OFFSET) - 1)
40 #define PM_PFRAME(x) ((x) & PM_PFRAME_MASK)
42 #define PM_PRESENT PM_STATUS(4LL)
43 #define PM_SWAP PM_STATUS(2LL)
51 #define PROC_KPAGEFLAGS "/proc/kpageflags"
53 /* copied from kpageflags_read() */
56 #define KPF_REFERENCED 2
57 #define KPF_UPTODATE 3
62 #define KPF_WRITEBACK 8
66 /* [11-20] new additions in 2.6.31 */
69 #define KPF_SWAPCACHE 13
70 #define KPF_SWAPBACKED 14
71 #define KPF_COMPOUND_HEAD 15
72 #define KPF_COMPOUND_TAIL 16
74 #define KPF_UNEVICTABLE 18
75 #define KPF_HWPOISON 19
79 /* [32-] kernel hacking assistances */
80 #define KPF_RESERVED 32
81 #define KPF_MLOCKED 33
82 #define KPF_MAPPEDTODISK 34
83 #define KPF_PRIVATE 35
84 #define KPF_PRIVATE_2 36
85 #define KPF_OWNER_PRIVATE 37
87 #define KPF_UNCACHED 39
89 /* [48-] take some arbitrary free slots for expanding overloaded flags
90 * not part of kernel API
92 #define KPF_READAHEAD 48
93 #define KPF_SLOB_FREE 49
94 #define KPF_SLUB_FROZEN 50
95 #define KPF_SLUB_DEBUG 51
97 #define KPF_ALL_BITS ((uint64_t)~0ULL)
98 #define KPF_HACKERS_BITS (0xffffULL << 32)
99 #define KPF_OVERLOADED_BITS (0xffffULL << 48)
100 #define BIT(name) (1ULL << KPF_##name)
101 #define BITS_COMPOUND (BIT(COMPOUND_HEAD) | BIT(COMPOUND_TAIL))
103 static char *page_flag_names
[] = {
104 [KPF_LOCKED
] = "L:locked",
105 [KPF_ERROR
] = "E:error",
106 [KPF_REFERENCED
] = "R:referenced",
107 [KPF_UPTODATE
] = "U:uptodate",
108 [KPF_DIRTY
] = "D:dirty",
110 [KPF_ACTIVE
] = "A:active",
111 [KPF_SLAB
] = "S:slab",
112 [KPF_WRITEBACK
] = "W:writeback",
113 [KPF_RECLAIM
] = "I:reclaim",
114 [KPF_BUDDY
] = "B:buddy",
116 [KPF_MMAP
] = "M:mmap",
117 [KPF_ANON
] = "a:anonymous",
118 [KPF_SWAPCACHE
] = "s:swapcache",
119 [KPF_SWAPBACKED
] = "b:swapbacked",
120 [KPF_COMPOUND_HEAD
] = "H:compound_head",
121 [KPF_COMPOUND_TAIL
] = "T:compound_tail",
122 [KPF_HUGE
] = "G:huge",
123 [KPF_UNEVICTABLE
] = "u:unevictable",
124 [KPF_HWPOISON
] = "X:hwpoison",
125 [KPF_NOPAGE
] = "n:nopage",
128 [KPF_RESERVED
] = "r:reserved",
129 [KPF_MLOCKED
] = "m:mlocked",
130 [KPF_MAPPEDTODISK
] = "d:mappedtodisk",
131 [KPF_PRIVATE
] = "P:private",
132 [KPF_PRIVATE_2
] = "p:private_2",
133 [KPF_OWNER_PRIVATE
] = "O:owner_private",
134 [KPF_ARCH
] = "h:arch",
135 [KPF_UNCACHED
] = "c:uncached",
137 [KPF_READAHEAD
] = "I:readahead",
138 [KPF_SLOB_FREE
] = "P:slob_free",
139 [KPF_SLUB_FROZEN
] = "A:slub_frozen",
140 [KPF_SLUB_DEBUG
] = "E:slub_debug",
148 static int opt_raw
; /* for kernel developers */
149 static int opt_list
; /* list pages (in ranges) */
150 static int opt_no_summary
; /* don't show summary */
151 static pid_t opt_pid
; /* process to walk */
153 #define MAX_ADDR_RANGES 1024
154 static int nr_addr_ranges
;
155 static unsigned long opt_offset
[MAX_ADDR_RANGES
];
156 static unsigned long opt_size
[MAX_ADDR_RANGES
];
158 #define MAX_VMAS 10240
160 static unsigned long pg_start
[MAX_VMAS
];
161 static unsigned long pg_end
[MAX_VMAS
];
163 #define MAX_BIT_FILTERS 64
164 static int nr_bit_filters
;
165 static uint64_t opt_mask
[MAX_BIT_FILTERS
];
166 static uint64_t opt_bits
[MAX_BIT_FILTERS
];
168 static int page_size
;
170 static int pagemap_fd
;
171 static int kpageflags_fd
;
173 #define HASH_SHIFT 13
174 #define HASH_SIZE (1 << HASH_SHIFT)
175 #define HASH_MASK (HASH_SIZE - 1)
176 #define HASH_KEY(flags) (flags & HASH_MASK)
178 static unsigned long total_pages
;
179 static unsigned long nr_pages
[HASH_SIZE
];
180 static uint64_t page_flags
[HASH_SIZE
];
187 #define ARRAY_SIZE(x) (sizeof(x) / sizeof((x)[0]))
189 #define min_t(type, x, y) ({ \
192 __min1 < __min2 ? __min1 : __min2; })
194 #define max_t(type, x, y) ({ \
197 __max1 > __max2 ? __max1 : __max2; })
199 static unsigned long pages2mb(unsigned long pages
)
201 return (pages
* page_size
) >> 20;
204 static void fatal(const char *x
, ...)
209 vfprintf(stderr
, x
, ap
);
214 int checked_open(const char *pathname
, int flags
)
216 int fd
= open(pathname
, flags
);
227 * pagemap/kpageflags routines
230 static unsigned long do_u64_read(int fd
, char *name
,
237 if (index
> ULONG_MAX
/ 8)
238 fatal("index overflow: %lu\n", index
);
240 if (lseek(fd
, index
* 8, SEEK_SET
) < 0) {
245 bytes
= read(fd
, buf
, count
* 8);
251 fatal("partial read: %lu bytes\n", bytes
);
256 static unsigned long kpageflags_read(uint64_t *buf
,
260 return do_u64_read(kpageflags_fd
, PROC_KPAGEFLAGS
, buf
, index
, pages
);
263 static unsigned long pagemap_read(uint64_t *buf
,
267 return do_u64_read(pagemap_fd
, "/proc/pid/pagemap", buf
, index
, pages
);
270 static unsigned long pagemap_pfn(uint64_t val
)
274 if (val
& PM_PRESENT
)
275 pfn
= PM_PFRAME(val
);
287 static char *page_flag_name(uint64_t flags
)
293 for (i
= 0, j
= 0; i
< ARRAY_SIZE(page_flag_names
); i
++) {
294 present
= (flags
>> i
) & 1;
295 if (!page_flag_names
[i
]) {
297 fatal("unkown flag bit %d\n", i
);
300 buf
[j
++] = present
? page_flag_names
[i
][0] : '_';
306 static char *page_flag_longname(uint64_t flags
)
308 static char buf
[1024];
311 for (i
= 0, n
= 0; i
< ARRAY_SIZE(page_flag_names
); i
++) {
312 if (!page_flag_names
[i
])
314 if ((flags
>> i
) & 1)
315 n
+= snprintf(buf
+ n
, sizeof(buf
) - n
, "%s,",
316 page_flag_names
[i
] + 2);
327 * page list and summary
330 static void show_page_range(unsigned long voffset
,
331 unsigned long offset
, uint64_t flags
)
333 static uint64_t flags0
;
334 static unsigned long voff
;
335 static unsigned long index
;
336 static unsigned long count
;
338 if (flags
== flags0
&& offset
== index
+ count
&&
339 (!opt_pid
|| voffset
== voff
+ count
)) {
346 printf("%lx\t", voff
);
347 printf("%lx\t%lx\t%s\n",
348 index
, count
, page_flag_name(flags0
));
357 static void show_page(unsigned long voffset
,
358 unsigned long offset
, uint64_t flags
)
361 printf("%lx\t", voffset
);
362 printf("%lx\t%s\n", offset
, page_flag_name(flags
));
365 static void show_summary(void)
369 printf(" flags\tpage-count MB"
370 " symbolic-flags\t\t\tlong-symbolic-flags\n");
372 for (i
= 0; i
< ARRAY_SIZE(nr_pages
); i
++) {
374 printf("0x%016llx\t%10lu %8lu %s\t%s\n",
375 (unsigned long long)page_flags
[i
],
377 pages2mb(nr_pages
[i
]),
378 page_flag_name(page_flags
[i
]),
379 page_flag_longname(page_flags
[i
]));
382 printf(" total\t%10lu %8lu\n",
383 total_pages
, pages2mb(total_pages
));
391 static int bit_mask_ok(uint64_t flags
)
395 for (i
= 0; i
< nr_bit_filters
; i
++) {
396 if (opt_bits
[i
] == KPF_ALL_BITS
) {
397 if ((flags
& opt_mask
[i
]) == 0)
400 if ((flags
& opt_mask
[i
]) != opt_bits
[i
])
408 static uint64_t expand_overloaded_flags(uint64_t flags
)
410 /* SLOB/SLUB overload several page flags */
411 if (flags
& BIT(SLAB
)) {
412 if (flags
& BIT(PRIVATE
))
413 flags
^= BIT(PRIVATE
) | BIT(SLOB_FREE
);
414 if (flags
& BIT(ACTIVE
))
415 flags
^= BIT(ACTIVE
) | BIT(SLUB_FROZEN
);
416 if (flags
& BIT(ERROR
))
417 flags
^= BIT(ERROR
) | BIT(SLUB_DEBUG
);
420 /* PG_reclaim is overloaded as PG_readahead in the read path */
421 if ((flags
& (BIT(RECLAIM
) | BIT(WRITEBACK
))) == BIT(RECLAIM
))
422 flags
^= BIT(RECLAIM
) | BIT(READAHEAD
);
427 static uint64_t well_known_flags(uint64_t flags
)
429 /* hide flags intended only for kernel hacker */
430 flags
&= ~KPF_HACKERS_BITS
;
432 /* hide non-hugeTLB compound pages */
433 if ((flags
& BITS_COMPOUND
) && !(flags
& BIT(HUGE
)))
434 flags
&= ~BITS_COMPOUND
;
443 static int hash_slot(uint64_t flags
)
445 int k
= HASH_KEY(flags
);
448 /* Explicitly reserve slot 0 for flags 0: the following logic
449 * cannot distinguish an unoccupied slot from slot (flags==0).
454 /* search through the remaining (HASH_SIZE-1) slots */
455 for (i
= 1; i
< ARRAY_SIZE(page_flags
); i
++, k
++) {
456 if (!k
|| k
>= ARRAY_SIZE(page_flags
))
458 if (page_flags
[k
] == 0) {
459 page_flags
[k
] = flags
;
462 if (page_flags
[k
] == flags
)
466 fatal("hash table full: bump up HASH_SHIFT?\n");
470 static void add_page(unsigned long voffset
,
471 unsigned long offset
, uint64_t flags
)
473 flags
= expand_overloaded_flags(flags
);
476 flags
= well_known_flags(flags
);
478 if (!bit_mask_ok(flags
))
482 show_page_range(voffset
, offset
, flags
);
483 else if (opt_list
== 2)
484 show_page(voffset
, offset
, flags
);
486 nr_pages
[hash_slot(flags
)]++;
490 #define KPAGEFLAGS_BATCH (64 << 10) /* 64k pages */
491 static void walk_pfn(unsigned long voffset
,
495 uint64_t buf
[KPAGEFLAGS_BATCH
];
501 batch
= min_t(unsigned long, count
, KPAGEFLAGS_BATCH
);
502 pages
= kpageflags_read(buf
, index
, batch
);
506 for (i
= 0; i
< pages
; i
++)
507 add_page(voffset
+ i
, index
+ i
, buf
[i
]);
514 #define PAGEMAP_BATCH (64 << 10)
515 static void walk_vma(unsigned long index
, unsigned long count
)
517 uint64_t buf
[PAGEMAP_BATCH
];
524 batch
= min_t(unsigned long, count
, PAGEMAP_BATCH
);
525 pages
= pagemap_read(buf
, index
, batch
);
529 for (i
= 0; i
< pages
; i
++) {
530 pfn
= pagemap_pfn(buf
[i
]);
532 walk_pfn(index
+ i
, pfn
, 1);
540 static void walk_task(unsigned long index
, unsigned long count
)
542 const unsigned long end
= index
+ count
;
546 while (index
< end
) {
548 while (pg_end
[i
] <= index
)
551 if (pg_start
[i
] >= end
)
554 start
= max_t(unsigned long, pg_start
[i
], index
);
555 index
= min_t(unsigned long, pg_end
[i
], end
);
557 assert(start
< index
);
558 walk_vma(start
, index
- start
);
562 static void add_addr_range(unsigned long offset
, unsigned long size
)
564 if (nr_addr_ranges
>= MAX_ADDR_RANGES
)
565 fatal("too many addr ranges\n");
567 opt_offset
[nr_addr_ranges
] = offset
;
568 opt_size
[nr_addr_ranges
] = min_t(unsigned long, size
, ULONG_MAX
-offset
);
572 static void walk_addr_ranges(void)
576 kpageflags_fd
= checked_open(PROC_KPAGEFLAGS
, O_RDONLY
);
579 add_addr_range(0, ULONG_MAX
);
581 for (i
= 0; i
< nr_addr_ranges
; i
++)
583 walk_pfn(0, opt_offset
[i
], opt_size
[i
]);
585 walk_task(opt_offset
[i
], opt_size
[i
]);
587 close(kpageflags_fd
);
595 static const char *page_flag_type(uint64_t flag
)
597 if (flag
& KPF_HACKERS_BITS
)
599 if (flag
& KPF_OVERLOADED_BITS
)
604 static void usage(void)
609 "page-types [options]\n"
610 " -r|--raw Raw mode, for kernel developers\n"
611 " -a|--addr addr-spec Walk a range of pages\n"
612 " -b|--bits bits-spec Walk pages with specified bits\n"
613 " -p|--pid pid Walk process address space\n"
614 #if 0 /* planned features */
615 " -f|--file filename Walk file address space\n"
617 " -l|--list Show page details in ranges\n"
618 " -L|--list-each Show page details one by one\n"
619 " -N|--no-summary Don't show summay info\n"
620 " -h|--help Show this usage message\n"
622 " N one page at offset N (unit: pages)\n"
623 " N+M pages range from N to N+M-1\n"
624 " N,M pages range from N to M-1\n"
625 " N, pages range from N to end\n"
626 " ,M pages range from 0 to M-1\n"
628 " bit1,bit2 (flags & (bit1|bit2)) != 0\n"
629 " bit1,bit2=bit1 (flags & (bit1|bit2)) == bit1\n"
630 " bit1,~bit2 (flags & (bit1|bit2)) == bit1\n"
631 " =bit1,bit2 flags == (bit1|bit2)\n"
635 for (i
= 0, j
= 0; i
< ARRAY_SIZE(page_flag_names
); i
++) {
636 if (!page_flag_names
[i
])
638 printf("%16s%s", page_flag_names
[i
] + 2,
639 page_flag_type(1ULL << i
));
646 "(r) raw mode bits (o) overloaded bits\n");
649 static unsigned long long parse_number(const char *str
)
651 unsigned long long n
;
653 n
= strtoll(str
, NULL
, 0);
655 if (n
== 0 && str
[0] != '0')
656 fatal("invalid name or number: %s\n", str
);
661 static void parse_pid(const char *str
)
666 opt_pid
= parse_number(str
);
668 sprintf(buf
, "/proc/%d/pagemap", opt_pid
);
669 pagemap_fd
= checked_open(buf
, O_RDONLY
);
671 sprintf(buf
, "/proc/%d/maps", opt_pid
);
672 file
= fopen(buf
, "r");
678 while (fgets(buf
, sizeof(buf
), file
) != NULL
) {
679 unsigned long vm_start
;
680 unsigned long vm_end
;
681 unsigned long long pgoff
;
687 n
= sscanf(buf
, "%lx-%lx %c%c%c%c %llx %x:%x %lu",
695 fprintf(stderr
, "unexpected line: %s\n", buf
);
698 pg_start
[nr_vmas
] = vm_start
/ page_size
;
699 pg_end
[nr_vmas
] = vm_end
/ page_size
;
700 if (++nr_vmas
>= MAX_VMAS
) {
701 fprintf(stderr
, "too many VMAs\n");
708 static void parse_file(const char *name
)
712 static void parse_addr_range(const char *optarg
)
714 unsigned long offset
;
718 p
= strchr(optarg
, ',');
720 p
= strchr(optarg
, '+');
724 size
= parse_number(p
+ 1);
726 offset
= parse_number(optarg
);
730 size
= parse_number(p
+ 1);
733 fatal("invalid range: %lu,%lu\n",
739 offset
= parse_number(optarg
);
743 add_addr_range(offset
, size
);
746 static void add_bits_filter(uint64_t mask
, uint64_t bits
)
748 if (nr_bit_filters
>= MAX_BIT_FILTERS
)
749 fatal("too much bit filters\n");
751 opt_mask
[nr_bit_filters
] = mask
;
752 opt_bits
[nr_bit_filters
] = bits
;
756 static uint64_t parse_flag_name(const char *str
, int len
)
763 if (len
<= 8 && !strncmp(str
, "compound", len
))
764 return BITS_COMPOUND
;
766 for (i
= 0; i
< ARRAY_SIZE(page_flag_names
); i
++) {
767 if (!page_flag_names
[i
])
769 if (!strncmp(str
, page_flag_names
[i
] + 2, len
))
773 return parse_number(str
);
776 static uint64_t parse_flag_names(const char *str
, int all
)
782 if (*p
== ',' || *p
== '=' || *p
== '\0') {
783 if ((*str
!= '~') || (*str
== '~' && all
&& *++str
))
784 flags
|= parse_flag_name(str
, p
- str
);
795 static void parse_bits_mask(const char *optarg
)
801 p
= strchr(optarg
, '=');
804 bits
= parse_flag_names(p
+ 1, 0);
806 mask
= parse_flag_names(optarg
, 0);
807 bits
= parse_flag_names(p
+ 1, 0);
808 } else if (strchr(optarg
, '~')) {
809 mask
= parse_flag_names(optarg
, 1);
810 bits
= parse_flag_names(optarg
, 0);
812 mask
= parse_flag_names(optarg
, 0);
816 add_bits_filter(mask
, bits
);
820 static struct option opts
[] = {
821 { "raw" , 0, NULL
, 'r' },
822 { "pid" , 1, NULL
, 'p' },
823 { "file" , 1, NULL
, 'f' },
824 { "addr" , 1, NULL
, 'a' },
825 { "bits" , 1, NULL
, 'b' },
826 { "list" , 0, NULL
, 'l' },
827 { "list-each" , 0, NULL
, 'L' },
828 { "no-summary", 0, NULL
, 'N' },
829 { "help" , 0, NULL
, 'h' },
830 { NULL
, 0, NULL
, 0 }
833 int main(int argc
, char *argv
[])
837 page_size
= getpagesize();
839 while ((c
= getopt_long(argc
, argv
,
840 "rp:f:a:b:lLNh", opts
, NULL
)) != -1) {
852 parse_addr_range(optarg
);
855 parse_bits_mask(optarg
);
875 if (opt_list
&& opt_pid
)
878 printf("offset\tlen\tflags\n");
880 printf("offset\tflags\n");
885 show_page_range(0, 0, 0); /* drain the buffer */