2 * page-types: Tool for querying page flags
4 * Copyright (C) 2009 Intel corporation
5 * Copyright (C) 2009 Wu Fengguang <fengguang.wu@intel.com>
8 #define _LARGEFILE64_SOURCE
18 #include <sys/types.h>
19 #include <sys/errno.h>
20 #include <sys/fcntl.h>
24 * pagemap kernel ABI bits
27 #define PM_ENTRY_BYTES sizeof(uint64_t)
28 #define PM_STATUS_BITS 3
29 #define PM_STATUS_OFFSET (64 - PM_STATUS_BITS)
30 #define PM_STATUS_MASK (((1LL << PM_STATUS_BITS) - 1) << PM_STATUS_OFFSET)
31 #define PM_STATUS(nr) (((nr) << PM_STATUS_OFFSET) & PM_STATUS_MASK)
32 #define PM_PSHIFT_BITS 6
33 #define PM_PSHIFT_OFFSET (PM_STATUS_OFFSET - PM_PSHIFT_BITS)
34 #define PM_PSHIFT_MASK (((1LL << PM_PSHIFT_BITS) - 1) << PM_PSHIFT_OFFSET)
35 #define PM_PSHIFT(x) (((u64) (x) << PM_PSHIFT_OFFSET) & PM_PSHIFT_MASK)
36 #define PM_PFRAME_MASK ((1LL << PM_PSHIFT_OFFSET) - 1)
37 #define PM_PFRAME(x) ((x) & PM_PFRAME_MASK)
39 #define PM_PRESENT PM_STATUS(4LL)
40 #define PM_SWAP PM_STATUS(2LL)
48 #define PROC_KPAGEFLAGS "/proc/kpageflags"
50 /* copied from kpageflags_read() */
53 #define KPF_REFERENCED 2
54 #define KPF_UPTODATE 3
59 #define KPF_WRITEBACK 8
63 /* [11-20] new additions in 2.6.31 */
66 #define KPF_SWAPCACHE 13
67 #define KPF_SWAPBACKED 14
68 #define KPF_COMPOUND_HEAD 15
69 #define KPF_COMPOUND_TAIL 16
71 #define KPF_UNEVICTABLE 18
72 #define KPF_HWPOISON 19
76 /* [32-] kernel hacking assistances */
77 #define KPF_RESERVED 32
78 #define KPF_MLOCKED 33
79 #define KPF_MAPPEDTODISK 34
80 #define KPF_PRIVATE 35
81 #define KPF_PRIVATE_2 36
82 #define KPF_OWNER_PRIVATE 37
84 #define KPF_UNCACHED 39
86 /* [48-] take some arbitrary free slots for expanding overloaded flags
87 * not part of kernel API
89 #define KPF_READAHEAD 48
90 #define KPF_SLOB_FREE 49
91 #define KPF_SLUB_FROZEN 50
92 #define KPF_SLUB_DEBUG 51
94 #define KPF_ALL_BITS ((uint64_t)~0ULL)
95 #define KPF_HACKERS_BITS (0xffffULL << 32)
96 #define KPF_OVERLOADED_BITS (0xffffULL << 48)
97 #define BIT(name) (1ULL << KPF_##name)
98 #define BITS_COMPOUND (BIT(COMPOUND_HEAD) | BIT(COMPOUND_TAIL))
100 static char *page_flag_names[] = {
101 [KPF_LOCKED] = "L:locked",
102 [KPF_ERROR] = "E:error",
103 [KPF_REFERENCED] = "R:referenced",
104 [KPF_UPTODATE] = "U:uptodate",
105 [KPF_DIRTY] = "D:dirty",
107 [KPF_ACTIVE] = "A:active",
108 [KPF_SLAB] = "S:slab",
109 [KPF_WRITEBACK] = "W:writeback",
110 [KPF_RECLAIM] = "I:reclaim",
111 [KPF_BUDDY] = "B:buddy",
113 [KPF_MMAP] = "M:mmap",
114 [KPF_ANON] = "a:anonymous",
115 [KPF_SWAPCACHE] = "s:swapcache",
116 [KPF_SWAPBACKED] = "b:swapbacked",
117 [KPF_COMPOUND_HEAD] = "H:compound_head",
118 [KPF_COMPOUND_TAIL] = "T:compound_tail",
119 [KPF_HUGE] = "G:huge",
120 [KPF_UNEVICTABLE] = "u:unevictable",
121 [KPF_HWPOISON] = "X:hwpoison",
122 [KPF_NOPAGE] = "n:nopage",
125 [KPF_RESERVED] = "r:reserved",
126 [KPF_MLOCKED] = "m:mlocked",
127 [KPF_MAPPEDTODISK] = "d:mappedtodisk",
128 [KPF_PRIVATE] = "P:private",
129 [KPF_PRIVATE_2] = "p:private_2",
130 [KPF_OWNER_PRIVATE] = "O:owner_private",
131 [KPF_ARCH] = "h:arch",
132 [KPF_UNCACHED] = "c:uncached",
134 [KPF_READAHEAD] = "I:readahead",
135 [KPF_SLOB_FREE] = "P:slob_free",
136 [KPF_SLUB_FROZEN] = "A:slub_frozen",
137 [KPF_SLUB_DEBUG] = "E:slub_debug",
145 static int opt_raw; /* for kernel developers */
146 static int opt_list; /* list pages (in ranges) */
147 static int opt_no_summary; /* don't show summary */
148 static pid_t opt_pid; /* process to walk */
150 #define MAX_ADDR_RANGES 1024
151 static int nr_addr_ranges;
152 static unsigned long opt_offset[MAX_ADDR_RANGES];
153 static unsigned long opt_size[MAX_ADDR_RANGES];
155 #define MAX_VMAS 10240
157 static unsigned long pg_start[MAX_VMAS];
158 static unsigned long pg_end[MAX_VMAS];
159 static unsigned long voffset;
161 static int pagemap_fd;
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 #define PAGES_BATCH (64 << 10) /* 64k pages */
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);
219 static char *page_flag_name(uint64_t flags)
225 for (i = 0, j = 0; i < ARRAY_SIZE(page_flag_names); i++) {
226 present = (flags >> i) & 1;
227 if (!page_flag_names[i]) {
229 fatal("unkown flag bit %d\n", i);
232 buf[j++] = present ? page_flag_names[i][0] : '_';
238 static char *page_flag_longname(uint64_t flags)
240 static char buf[1024];
243 for (i = 0, n = 0; i < ARRAY_SIZE(page_flag_names); i++) {
244 if (!page_flag_names[i])
246 if ((flags >> i) & 1)
247 n += snprintf(buf + n, sizeof(buf) - n, "%s,",
248 page_flag_names[i] + 2);
259 * page list and summary
262 static void show_page_range(unsigned long offset, uint64_t flags)
264 static uint64_t flags0;
265 static unsigned long voff;
266 static unsigned long index;
267 static unsigned long count;
269 if (flags == flags0 && offset == index + count &&
270 (!opt_pid || voffset == voff + count)) {
277 printf("%lx\t", voff);
278 printf("%lx\t%lx\t%s\n",
279 index, count, page_flag_name(flags0));
288 static void show_page(unsigned long offset, uint64_t flags)
291 printf("%lx\t", voffset);
292 printf("%lx\t%s\n", offset, page_flag_name(flags));
295 static void show_summary(void)
299 printf(" flags\tpage-count MB"
300 " symbolic-flags\t\t\tlong-symbolic-flags\n");
302 for (i = 0; i < ARRAY_SIZE(nr_pages); i++) {
304 printf("0x%016llx\t%10lu %8lu %s\t%s\n",
305 (unsigned long long)page_flags[i],
307 pages2mb(nr_pages[i]),
308 page_flag_name(page_flags[i]),
309 page_flag_longname(page_flags[i]));
312 printf(" total\t%10lu %8lu\n",
313 total_pages, pages2mb(total_pages));
321 static int bit_mask_ok(uint64_t flags)
325 for (i = 0; i < nr_bit_filters; i++) {
326 if (opt_bits[i] == KPF_ALL_BITS) {
327 if ((flags & opt_mask[i]) == 0)
330 if ((flags & opt_mask[i]) != opt_bits[i])
338 static uint64_t expand_overloaded_flags(uint64_t flags)
340 /* SLOB/SLUB overload several page flags */
341 if (flags & BIT(SLAB)) {
342 if (flags & BIT(PRIVATE))
343 flags ^= BIT(PRIVATE) | BIT(SLOB_FREE);
344 if (flags & BIT(ACTIVE))
345 flags ^= BIT(ACTIVE) | BIT(SLUB_FROZEN);
346 if (flags & BIT(ERROR))
347 flags ^= BIT(ERROR) | BIT(SLUB_DEBUG);
350 /* PG_reclaim is overloaded as PG_readahead in the read path */
351 if ((flags & (BIT(RECLAIM) | BIT(WRITEBACK))) == BIT(RECLAIM))
352 flags ^= BIT(RECLAIM) | BIT(READAHEAD);
357 static uint64_t well_known_flags(uint64_t flags)
359 /* hide flags intended only for kernel hacker */
360 flags &= ~KPF_HACKERS_BITS;
362 /* hide non-hugeTLB compound pages */
363 if ((flags & BITS_COMPOUND) && !(flags & BIT(HUGE)))
364 flags &= ~BITS_COMPOUND;
374 static int hash_slot(uint64_t flags)
376 int k = HASH_KEY(flags);
379 /* Explicitly reserve slot 0 for flags 0: the following logic
380 * cannot distinguish an unoccupied slot from slot (flags==0).
385 /* search through the remaining (HASH_SIZE-1) slots */
386 for (i = 1; i < ARRAY_SIZE(page_flags); i++, k++) {
387 if (!k || k >= ARRAY_SIZE(page_flags))
389 if (page_flags[k] == 0) {
390 page_flags[k] = flags;
393 if (page_flags[k] == flags)
397 fatal("hash table full: bump up HASH_SHIFT?\n");
401 static void add_page(unsigned long offset, uint64_t flags)
403 flags = expand_overloaded_flags(flags);
406 flags = well_known_flags(flags);
408 if (!bit_mask_ok(flags))
412 show_page_range(offset, flags);
413 else if (opt_list == 2)
414 show_page(offset, flags);
416 nr_pages[hash_slot(flags)]++;
420 static void walk_pfn(unsigned long index, unsigned long count)
426 if (index > ULONG_MAX / KPF_BYTES)
427 fatal("index overflow: %lu\n", index);
429 lseek(kpageflags_fd, index * KPF_BYTES, SEEK_SET);
432 uint64_t kpageflags_buf[KPF_BYTES * PAGES_BATCH];
434 batch = min_t(unsigned long, count, PAGES_BATCH);
435 n = read(kpageflags_fd, kpageflags_buf, batch * KPF_BYTES);
439 perror(PROC_KPAGEFLAGS);
443 if (n % KPF_BYTES != 0)
444 fatal("partial read: %lu bytes\n", n);
447 for (i = 0; i < n; i++)
448 add_page(index + i, kpageflags_buf[i]);
456 #define PAGEMAP_BATCH 4096
457 static unsigned long task_pfn(unsigned long pgoff)
459 static uint64_t buf[PAGEMAP_BATCH];
460 static unsigned long start;
464 if (pgoff < start || pgoff >= start + count) {
465 if (lseek64(pagemap_fd,
466 (uint64_t)pgoff * PM_ENTRY_BYTES,
468 perror("pagemap seek");
471 count = read(pagemap_fd, buf, sizeof(buf));
475 perror("pagemap read");
478 if (count % PM_ENTRY_BYTES) {
479 fatal("pagemap read not aligned.\n");
482 count /= PM_ENTRY_BYTES;
486 pfn = buf[pgoff - start];
487 if (pfn & PM_PRESENT)
488 pfn = PM_PFRAME(pfn);
495 static void walk_task(unsigned long index, unsigned long count)
498 const unsigned long end = index + count;
500 while (index < end) {
502 while (pg_end[i] <= index)
505 if (pg_start[i] >= end)
508 voffset = max_t(unsigned long, pg_start[i], index);
509 index = min_t(unsigned long, pg_end[i], end);
511 assert(voffset < index);
512 for (; voffset < index; voffset++) {
513 unsigned long pfn = task_pfn(voffset);
520 static void add_addr_range(unsigned long offset, unsigned long size)
522 if (nr_addr_ranges >= MAX_ADDR_RANGES)
523 fatal("too many addr ranges\n");
525 opt_offset[nr_addr_ranges] = offset;
526 opt_size[nr_addr_ranges] = min_t(unsigned long, size, ULONG_MAX-offset);
530 static void walk_addr_ranges(void)
534 kpageflags_fd = open(PROC_KPAGEFLAGS, O_RDONLY);
535 if (kpageflags_fd < 0) {
536 perror(PROC_KPAGEFLAGS);
541 add_addr_range(0, ULONG_MAX);
543 for (i = 0; i < nr_addr_ranges; i++)
545 walk_pfn(opt_offset[i], opt_size[i]);
547 walk_task(opt_offset[i], opt_size[i]);
549 close(kpageflags_fd);
557 static const char *page_flag_type(uint64_t flag)
559 if (flag & KPF_HACKERS_BITS)
561 if (flag & KPF_OVERLOADED_BITS)
566 static void usage(void)
571 "page-types [options]\n"
572 " -r|--raw Raw mode, for kernel developers\n"
573 " -a|--addr addr-spec Walk a range of pages\n"
574 " -b|--bits bits-spec Walk pages with specified bits\n"
575 " -p|--pid pid Walk process address space\n"
576 #if 0 /* planned features */
577 " -f|--file filename Walk file address space\n"
579 " -l|--list Show page details in ranges\n"
580 " -L|--list-each Show page details one by one\n"
581 " -N|--no-summary Don't show summay info\n"
582 " -h|--help Show this usage message\n"
584 " N one page at offset N (unit: pages)\n"
585 " N+M pages range from N to N+M-1\n"
586 " N,M pages range from N to M-1\n"
587 " N, pages range from N to end\n"
588 " ,M pages range from 0 to M-1\n"
590 " bit1,bit2 (flags & (bit1|bit2)) != 0\n"
591 " bit1,bit2=bit1 (flags & (bit1|bit2)) == bit1\n"
592 " bit1,~bit2 (flags & (bit1|bit2)) == bit1\n"
593 " =bit1,bit2 flags == (bit1|bit2)\n"
597 for (i = 0, j = 0; i < ARRAY_SIZE(page_flag_names); i++) {
598 if (!page_flag_names[i])
600 printf("%16s%s", page_flag_names[i] + 2,
601 page_flag_type(1ULL << i));
608 "(r) raw mode bits (o) overloaded bits\n");
611 static unsigned long long parse_number(const char *str)
613 unsigned long long n;
615 n = strtoll(str, NULL, 0);
617 if (n == 0 && str[0] != '0')
618 fatal("invalid name or number: %s\n", str);
623 static void parse_pid(const char *str)
628 opt_pid = parse_number(str);
630 sprintf(buf, "/proc/%d/pagemap", opt_pid);
631 pagemap_fd = open(buf, O_RDONLY);
632 if (pagemap_fd < 0) {
637 sprintf(buf, "/proc/%d/maps", opt_pid);
638 file = fopen(buf, "r");
644 while (fgets(buf, sizeof(buf), file) != NULL) {
645 unsigned long vm_start;
646 unsigned long vm_end;
647 unsigned long long pgoff;
653 n = sscanf(buf, "%lx-%lx %c%c%c%c %llx %x:%x %lu",
661 fprintf(stderr, "unexpected line: %s\n", buf);
664 pg_start[nr_vmas] = vm_start / page_size;
665 pg_end[nr_vmas] = vm_end / page_size;
666 if (++nr_vmas >= MAX_VMAS) {
667 fprintf(stderr, "too many VMAs\n");
674 static void parse_file(const char *name)
678 static void parse_addr_range(const char *optarg)
680 unsigned long offset;
684 p = strchr(optarg, ',');
686 p = strchr(optarg, '+');
690 size = parse_number(p + 1);
692 offset = parse_number(optarg);
696 size = parse_number(p + 1);
699 fatal("invalid range: %lu,%lu\n",
705 offset = parse_number(optarg);
709 add_addr_range(offset, size);
712 static void add_bits_filter(uint64_t mask, uint64_t bits)
714 if (nr_bit_filters >= MAX_BIT_FILTERS)
715 fatal("too much bit filters\n");
717 opt_mask[nr_bit_filters] = mask;
718 opt_bits[nr_bit_filters] = bits;
722 static uint64_t parse_flag_name(const char *str, int len)
729 if (len <= 8 && !strncmp(str, "compound", len))
730 return BITS_COMPOUND;
732 for (i = 0; i < ARRAY_SIZE(page_flag_names); i++) {
733 if (!page_flag_names[i])
735 if (!strncmp(str, page_flag_names[i] + 2, len))
739 return parse_number(str);
742 static uint64_t parse_flag_names(const char *str, int all)
748 if (*p == ',' || *p == '=' || *p == '\0') {
749 if ((*str != '~') || (*str == '~' && all && *++str))
750 flags |= parse_flag_name(str, p - str);
761 static void parse_bits_mask(const char *optarg)
767 p = strchr(optarg, '=');
770 bits = parse_flag_names(p + 1, 0);
772 mask = parse_flag_names(optarg, 0);
773 bits = parse_flag_names(p + 1, 0);
774 } else if (strchr(optarg, '~')) {
775 mask = parse_flag_names(optarg, 1);
776 bits = parse_flag_names(optarg, 0);
778 mask = parse_flag_names(optarg, 0);
782 add_bits_filter(mask, bits);
786 static struct option opts[] = {
787 { "raw" , 0, NULL, 'r' },
788 { "pid" , 1, NULL, 'p' },
789 { "file" , 1, NULL, 'f' },
790 { "addr" , 1, NULL, 'a' },
791 { "bits" , 1, NULL, 'b' },
792 { "list" , 0, NULL, 'l' },
793 { "list-each" , 0, NULL, 'L' },
794 { "no-summary", 0, NULL, 'N' },
795 { "help" , 0, NULL, 'h' },
796 { NULL , 0, NULL, 0 }
799 int main(int argc, char *argv[])
803 page_size = getpagesize();
805 while ((c = getopt_long(argc, argv,
806 "rp:f:a:b:lLNh", opts, NULL)) != -1) {
818 parse_addr_range(optarg);
821 parse_bits_mask(optarg);
841 if (opt_list && opt_pid)
844 printf("offset\tlen\tflags\n");
846 printf("offset\tflags\n");
851 show_page_range(0, 0); /* drain the buffer */