// SPDX-License-Identifier: GPL-2.0-only /* * page-types: Tool for querying page flags * * Copyright (C) 2009 Intel corporation * * Authors: Wu Fengguang <fengguang.wu@intel.com> */ #define _FILE_OFFSET_BITS 64 #define _GNU_SOURCE #include <stdio.h> #include <stdlib.h> #include <unistd.h> #include <stdint.h> #include <stdarg.h> #include <string.h> #include <getopt.h> #include <limits.h> #include <assert.h> #include <ftw.h> #include <time.h> #include <setjmp.h> #include <signal.h> #include <sys/types.h> #include <sys/errno.h> #include <sys/fcntl.h> #include <sys/mount.h> #include <sys/statfs.h> #include <sys/mman.h> #include "../../include/uapi/linux/magic.h" #include "../../include/uapi/linux/kernel-page-flags.h" #include <api/fs/fs.h> #ifndef MAX_PATH # define MAX_PATH 256 #endif #ifndef STR # define _STR(x) #x # define STR(x) _STR(x) #endif /* * pagemap kernel ABI bits */ #define PM_ENTRY_BYTES 8 #define PM_PFRAME_BITS 55 #define PM_PFRAME_MASK ((1LL << PM_PFRAME_BITS) - 1) #define PM_PFRAME(x) ((x) & PM_PFRAME_MASK) #define MAX_SWAPFILES_SHIFT 5 #define PM_SWAP_OFFSET(x) (((x) & PM_PFRAME_MASK) >> MAX_SWAPFILES_SHIFT) #define PM_SOFT_DIRTY (1ULL << 55) #define PM_MMAP_EXCLUSIVE (1ULL << 56) #define PM_FILE (1ULL << 61) #define PM_SWAP (1ULL << 62) #define PM_PRESENT (1ULL << 63) /* * kernel page flags */ #define KPF_BYTES 8 #define PROC_KPAGEFLAGS "/proc/kpageflags" #define PROC_KPAGECOUNT "/proc/kpagecount" #define PROC_KPAGECGROUP "/proc/kpagecgroup" #define SYS_KERNEL_MM_PAGE_IDLE "/sys/kernel/mm/page_idle/bitmap" /* [32-] kernel hacking assistances */ #define KPF_RESERVED 32 #define KPF_MLOCKED 33 #define KPF_MAPPEDTODISK 34 #define KPF_PRIVATE 35 #define KPF_PRIVATE_2 36 #define KPF_OWNER_PRIVATE 37 #define KPF_ARCH 38 #define KPF_UNCACHED 39 #define KPF_SOFTDIRTY 40 #define KPF_ARCH_2 41 /* [47-] take some arbitrary free slots for expanding overloaded flags * not part of kernel API */ #define KPF_ANON_EXCLUSIVE 47 #define KPF_READAHEAD 48 #define KPF_SLUB_FROZEN 50 #define KPF_SLUB_DEBUG 51 #define KPF_FILE 61 #define KPF_SWAP 62 #define KPF_MMAP_EXCLUSIVE 63 #define KPF_ALL_BITS ((uint64_t)~0ULL) #define KPF_HACKERS_BITS (0xffffULL << 32) #define KPF_OVERLOADED_BITS (0xffffULL << 48) #define BIT(name) (1ULL << KPF_##name) #define BITS_COMPOUND (BIT(COMPOUND_HEAD) | BIT(COMPOUND_TAIL)) static const char * const page_flag_names[] = { [KPF_LOCKED] = "L:locked", [KPF_ERROR] = "E:error", [KPF_REFERENCED] = "R:referenced", [KPF_UPTODATE] = "U:uptodate", [KPF_DIRTY] = "D:dirty", [KPF_LRU] = "l:lru", [KPF_ACTIVE] = "A:active", [KPF_SLAB] = "S:slab", [KPF_WRITEBACK] = "W:writeback", [KPF_RECLAIM] = "I:reclaim", [KPF_BUDDY] = "B:buddy", [KPF_MMAP] = "M:mmap", [KPF_ANON] = "a:anonymous", [KPF_SWAPCACHE] = "s:swapcache", [KPF_SWAPBACKED] = "b:swapbacked", [KPF_COMPOUND_HEAD] = "H:compound_head", [KPF_COMPOUND_TAIL] = "T:compound_tail", [KPF_HUGE] = "G:huge", [KPF_UNEVICTABLE] = "u:unevictable", [KPF_HWPOISON] = "X:hwpoison", [KPF_NOPAGE] = "n:nopage", [KPF_KSM] = "x:ksm", [KPF_THP] = "t:thp", [KPF_OFFLINE] = "o:offline", [KPF_PGTABLE] = "g:pgtable", [KPF_ZERO_PAGE] = "z:zero_page", [KPF_IDLE] = "i:idle_page", [KPF_RESERVED] = "r:reserved", [KPF_MLOCKED] = "m:mlocked", [KPF_MAPPEDTODISK] = "d:mappedtodisk", [KPF_PRIVATE] = "P:private", [KPF_PRIVATE_2] = "p:private_2", [KPF_OWNER_PRIVATE] = "O:owner_private", [KPF_ARCH] = "h:arch", [KPF_UNCACHED] = "c:uncached", [KPF_SOFTDIRTY] = "f:softdirty", [KPF_ARCH_2] = "H:arch_2", [KPF_ANON_EXCLUSIVE] = "d:anon_exclusive", [KPF_READAHEAD] = "I:readahead", [KPF_SLUB_FROZEN] = "A:slub_frozen", [KPF_SLUB_DEBUG] = "E:slub_debug", [KPF_FILE] = "F:file", [KPF_SWAP] = "w:swap", [KPF_MMAP_EXCLUSIVE] = "1:mmap_exclusive", }; /* * data structures */ static int opt_raw; /* for kernel developers */ static int opt_list; /* list pages (in ranges) */ static int opt_mark_idle; /* set accessed bit */ static int opt_no_summary; /* don't show summary */ static pid_t opt_pid; /* process to walk */ const char *opt_file; /* file or directory path */ static uint64_t opt_cgroup; /* cgroup inode */ static int opt_list_cgroup;/* list page cgroup */ static int opt_list_mapcnt;/* list page map count */ static const char *opt_kpageflags;/* kpageflags file to parse */ #define MAX_ADDR_RANGES 1024 static int nr_addr_ranges; static unsigned long opt_offset[MAX_ADDR_RANGES]; static unsigned long opt_size[MAX_ADDR_RANGES]; #define MAX_VMAS 10240 static int nr_vmas; static unsigned long pg_start[MAX_VMAS]; static unsigned long pg_end[MAX_VMAS]; #define MAX_BIT_FILTERS 64 static int nr_bit_filters; static uint64_t opt_mask[MAX_BIT_FILTERS]; static uint64_t opt_bits[MAX_BIT_FILTERS]; static int page_size; static int pagemap_fd; static int kpageflags_fd; static int kpagecount_fd = -1; static int kpagecgroup_fd = -1; static int page_idle_fd = -1; static int opt_hwpoison; static int opt_unpoison; static const char *hwpoison_debug_fs; static int hwpoison_inject_fd; static int hwpoison_forget_fd; #define HASH_SHIFT 13 #define HASH_SIZE (1 << HASH_SHIFT) #define HASH_MASK (HASH_SIZE - 1) #define HASH_KEY(flags) (flags & HASH_MASK) static unsigned long total_pages; static unsigned long nr_pages[HASH_SIZE]; static uint64_t page_flags[HASH_SIZE]; /* * helper functions */ #define ARRAY_SIZE(x) (sizeof(x) / sizeof((x)[0])) #define min_t(type, x, y) ({ \ type __min1 = (x); \ type __min2 = (y); \ __min1 < __min2 ? __min1 : __min2; }) #define max_t(type, x, y) ({ \ type __max1 = (x); \ type __max2 = (y); \ __max1 > __max2 ? __max1 : __max2; }) static unsigned long pages2mb(unsigned long pages) { return (pages * page_size) >> 20; } static void fatal(const char *x, ...) { va_list ap; va_start(ap, x); vfprintf(stderr, x, ap); va_end(ap); exit(EXIT_FAILURE); } static int checked_open(const char *pathname, int flags) { int fd = open(pathname, flags); if (fd < 0) { perror(pathname); exit(EXIT_FAILURE); } return fd; } /* * pagemap/kpageflags routines */ static unsigned long do_u64_read(int fd, const char *name, uint64_t *buf, unsigned long index, unsigned long count) { long bytes; if (index > ULONG_MAX / 8) fatal("index overflow: %lu\n", index); bytes = pread(fd, buf, count * 8, (off_t)index * 8); if (bytes < 0) { perror(name); exit(EXIT_FAILURE); } if (bytes % 8) fatal("partial read: %lu bytes\n", bytes); return bytes / 8; } static unsigned long kpageflags_read(uint64_t *buf, unsigned long index, unsigned long pages) { return do_u64_read(kpageflags_fd, opt_kpageflags, buf, index, pages); } static unsigned long kpagecgroup_read(uint64_t *buf, unsigned long index, unsigned long pages) { if (kpagecgroup_fd < 0) return pages; return do_u64_read(kpagecgroup_fd, opt_kpageflags, buf, index, pages); } static unsigned long kpagecount_read(uint64_t *buf, unsigned long index, unsigned long pages) { return kpagecount_fd < 0 ? pages : do_u64_read(kpagecount_fd, PROC_KPAGECOUNT, buf, index, pages); } static unsigned long pagemap_read(uint64_t *buf, unsigned long index, unsigned long pages) { return do_u64_read(pagemap_fd, "/proc/pid/pagemap", buf, index, pages); } static unsigned long pagemap_pfn(uint64_t val) { unsigned long pfn; if (val & PM_PRESENT) pfn = PM_PFRAME(val); else pfn = 0; return pfn; } static unsigned long pagemap_swap_offset(uint64_t val) { return val & PM_SWAP ? PM_SWAP_OFFSET(val) : 0; } /* * page flag names */ static char *page_flag_name(uint64_t flags) { static char buf[65]; int present; size_t i, j; for (i = 0, j = 0; i < ARRAY_SIZE(page_flag_names); i++) { present = (flags >> i) & 1; if (!page_flag_names[i]) { if (present) fatal("unknown flag bit %d\n", i); continue; } buf[j++] = present ? page_flag_names[i][0] : '_'; } return buf; } static char *page_flag_longname(uint64_t flags) { static char buf[1024]; size_t i, n; for (i = 0, n = 0; i < ARRAY_SIZE(page_flag_names); i++) { if (!page_flag_names[i]) continue; if ((flags >> i) & 1) n += snprintf(buf + n, sizeof(buf) - n, "%s,", page_flag_names[i] + 2); } if (n) n--; buf[n] = '\0'; return buf; } /* * page list and summary */ static void show_page_range(unsigned long voffset, unsigned long offset, unsigned long size, uint64_t flags, uint64_t cgroup, uint64_t mapcnt) { static uint64_t flags0; static uint64_t cgroup0; static uint64_t mapcnt0; static unsigned long voff; static unsigned long index; static unsigned long count; if (flags == flags0 && cgroup == cgroup0 && mapcnt == mapcnt0 && offset == index + count && size && voffset == voff + count) { count += size; return; } if (count) { if (opt_pid) printf("%lx\t", voff); if (opt_file) printf("%lx\t", voff); if (opt_list_cgroup) printf("@%llu\t", (unsigned long long)cgroup0); if (opt_list_mapcnt) printf("%lu\t", mapcnt0); printf("%lx\t%lx\t%s\n", index, count, page_flag_name(flags0)); } flags0 = flags; cgroup0 = cgroup; mapcnt0 = mapcnt; index = offset; voff = voffset; count = size; } static void flush_page_range(void) { show_page_range(0, 0, 0, 0, 0, 0); } static void show_page(unsigned long voffset, unsigned long offset, uint64_t flags, uint64_t cgroup, uint64_t mapcnt) { if (opt_pid) printf("%lx\t", voffset); if (opt_file) printf("%lx\t", voffset); if (opt_list_cgroup) printf("@%llu\t", (unsigned long long)cgroup); if (opt_list_mapcnt) printf("%lu\t", mapcnt); printf("%lx\t%s\n", offset, page_flag_name(flags)); } static void show_summary(void) { size_t i; printf(" flags\tpage-count MB" " symbolic-flags\t\t\tlong-symbolic-flags\n"); for (i = 0; i < ARRAY_SIZE(nr_pages); i++) { if (nr_pages[i]) printf("0x%016llx\t%10lu %8lu %s\t%s\n", (unsigned long long)page_flags[i], nr_pages[i], pages2mb(nr_pages[i]), page_flag_name(page_flags[i]), page_flag_longname(page_flags[i])); } printf(" total\t%10lu %8lu\n", total_pages, pages2mb(total_pages)); } /* * page flag filters */ static int bit_mask_ok(uint64_t flags) { int i; for (i = 0; i < nr_bit_filters; i++) { if (opt_bits[i] == KPF_ALL_BITS) { if ((flags & opt_mask[i]) == 0) return 0; } else { if ((flags & opt_mask[i]) != opt_bits[i]) return 0; } } return 1; } static uint64_t expand_overloaded_flags(uint64_t flags, uint64_t pme) { /* Anonymous pages overload PG_mappedtodisk */ if ((flags & BIT(ANON)) && (flags & BIT(MAPPEDTODISK))) flags ^= BIT(MAPPEDTODISK) | BIT(ANON_EXCLUSIVE); /* SLUB overloads several page flags */ if (flags & BIT(SLAB)) { if (flags & BIT(ACTIVE)) flags ^= BIT(ACTIVE) | BIT(SLUB_FROZEN); if (flags & BIT(ERROR)) flags ^= BIT(ERROR) | BIT(SLUB_DEBUG); } /* PG_reclaim is overloaded as PG_readahead in the read path */ if ((flags & (BIT(RECLAIM) | BIT(WRITEBACK))) == BIT(RECLAIM)) flags ^= BIT(RECLAIM) | BIT(READAHEAD); if (pme & PM_SOFT_DIRTY) flags |= BIT(SOFTDIRTY); if (pme & PM_FILE) flags |= BIT(FILE); if (pme & PM_SWAP) flags |= BIT(SWAP); if (pme & PM_MMAP_EXCLUSIVE) flags |= BIT(MMAP_EXCLUSIVE); return flags; } static uint64_t well_known_flags(uint64_t flags) { /* hide flags intended only for kernel hacker */ flags &= ~KPF_HACKERS_BITS; /* hide non-hugeTLB compound pages */ if ((flags & BITS_COMPOUND) && !(flags & BIT(HUGE))) flags &= ~BITS_COMPOUND; return flags; } static uint64_t kpageflags_flags(uint64_t flags, uint64_t pme) { if (opt_raw) flags = expand_overloaded_flags(flags, pme); else flags = well_known_flags(flags); return flags; } /* * page actions */ static void prepare_hwpoison_fd(void) { char buf[MAX_PATH + 1]; hwpoison_debug_fs = debugfs__mount(); if (!hwpoison_debug_fs) { perror("mount debugfs"); exit(EXIT_FAILURE); } if (opt_hwpoison && !hwpoison_inject_fd) { snprintf(buf, MAX_PATH, "%s/hwpoison/corrupt-pfn", hwpoison_debug_fs); hwpoison_inject_fd = checked_open(buf, O_WRONLY); } if (opt_unpoison && !hwpoison_forget_fd) { snprintf(buf, MAX_PATH, "%s/hwpoison/unpoison-pfn", hwpoison_debug_fs); hwpoison_forget_fd = checked_open(buf, O_WRONLY); } } static int hwpoison_page(unsigned long offset) { char buf[100]; int len; len = sprintf(buf, "0x%lx\n", offset); len = write(hwpoison_inject_fd, buf, len); if (len < 0) { perror("hwpoison inject"); return len; } return 0; } static int unpoison_page(unsigned long offset) { char buf[100]; int len; len = sprintf(buf, "0x%lx\n", offset); len = write(hwpoison_forget_fd, buf, len); if (len < 0) { perror("hwpoison forget"); return len; } return 0; } static int mark_page_idle(unsigned long offset) { static unsigned long off; static uint64_t buf; int len; if ((offset / 64 == off / 64) || buf == 0) { buf |= 1UL << (offset % 64); off = offset; return 0; } len = pwrite(page_idle_fd, &buf, 8, 8 * (off / 64)); if (len < 0) { perror("mark page idle"); return len; } buf = 1UL << (offset % 64); off = offset; return 0; } /* * page frame walker */ static size_t hash_slot(uint64_t flags) { size_t k = HASH_KEY(flags); size_t i; /* Explicitly reserve slot 0 for flags 0: the following logic * cannot distinguish an unoccupied slot from slot (flags==0). */ if (flags == 0) return 0; /* search through the remaining (HASH_SIZE-1) slots */ for (i = 1; i < ARRAY_SIZE(page_flags); i++, k++) { if (!k || k >= ARRAY_SIZE(page_flags)) k = 1; if (page_flags[k] == 0) { page_flags[k] = flags; return k; } if (page_flags[k] == flags) return k; } fatal("hash table full: bump up HASH_SHIFT?\n"); exit(EXIT_FAILURE); } static void add_page(unsigned long voffset, unsigned long offset, uint64_t flags, uint64_t cgroup, uint64_t mapcnt, uint64_t pme) { flags = kpageflags_flags(flags, pme); if (!bit_mask_ok(flags)) return; if (opt_cgroup && cgroup != (uint64_t)opt_cgroup) return; if (opt_hwpoison) hwpoison_page(offset); if (opt_unpoison) unpoison_page(offset); if (opt_mark_idle) mark_page_idle(offset); if (opt_list == 1) show_page_range(voffset, offset, 1, flags, cgroup, mapcnt); else if (opt_list == 2) show_page(voffset, offset, flags, cgroup, mapcnt); nr_pages[hash_slot(flags)]++; total_pages++; } #define KPAGEFLAGS_BATCH (64 << 10) /* 64k pages */ static void walk_pfn(unsigned long voffset, unsigned long index, unsigned long count, uint64_t pme) { uint64_t buf[KPAGEFLAGS_BATCH]; uint64_t cgi[KPAGEFLAGS_BATCH]; uint64_t cnt[KPAGEFLAGS_BATCH]; unsigned long batch; unsigned long pages; unsigned long i; /* * kpagecgroup_read() reads only if kpagecgroup were opened, but * /proc/kpagecgroup might even not exist, so it's better to fill * them with zeros here. */ if (count == 1) cgi[0] = 0; else memset(cgi, 0, sizeof cgi); while (count) { batch = min_t(unsigned long, count, KPAGEFLAGS_BATCH); pages = kpageflags_read(buf, index, batch); if (pages == 0) break; if (kpagecgroup_read(cgi, index, pages) != pages) fatal("kpagecgroup returned fewer pages than expected"); if (kpagecount_read(cnt, index, pages) != pages) fatal("kpagecount returned fewer pages than expected"); for (i = 0; i < pages; i++) add_page(voffset + i, index + i, buf[i], cgi[i], cnt[i], pme); index += pages; count -= pages; } } static void walk_swap(unsigned long voffset, uint64_t pme) { uint64_t flags = kpageflags_flags(0, pme); if (!bit_mask_ok(flags)) return; if (opt_cgroup) return; if (opt_list == 1) show_page_range(voffset, pagemap_swap_offset(pme), 1, flags, 0, 0); else if (opt_list == 2) show_page(voffset, pagemap_swap_offset(pme), flags, 0, 0); nr_pages[hash_slot(flags)]++; total_pages++; } #define PAGEMAP_BATCH (64 << 10) static void walk_vma(unsigned long index, unsigned long count) { uint64_t buf[PAGEMAP_BATCH]; unsigned long batch; unsigned long pages; unsigned long pfn; unsigned long i; while (count) { batch = min_t(unsigned long, count, PAGEMAP_BATCH); pages = pagemap_read(buf, index, batch); if (pages == 0) break; for (i = 0; i < pages; i++) { pfn = pagemap_pfn(buf[i]); if (pfn) walk_pfn(index + i, pfn, 1, buf[i]); if (buf[i] & PM_SWAP) walk_swap(index + i, buf[i]); } index += pages; count -= pages; } } static void walk_task(unsigned long index, unsigned long count) { const unsigned long end = index + count; unsigned long start; int i = 0; while (index < end) { while (pg_end[i] <= index) if (++i >= nr_vmas) return; if (pg_start[i] >= end) return; start = max_t(unsigned long, pg_start[i], index); index = min_t(unsigned long, pg_end[i], end); assert(start < index); walk_vma(start, index - start); } } static void add_addr_range(unsigned long offset, unsigned long size) { if (nr_addr_ranges >= MAX_ADDR_RANGES) fatal("too many addr ranges\n"); opt_offset[nr_addr_ranges] = offset; opt_size[nr_addr_ranges] = min_t(unsigned long, size, ULONG_MAX-offset); nr_addr_ranges++; } static void walk_addr_ranges(void) { int i; kpageflags_fd = checked_open(opt_kpageflags, O_RDONLY); if (!nr_addr_ranges) add_addr_range(0, ULONG_MAX); for (i = 0; i < nr_addr_ranges; i++) if (!opt_pid) walk_pfn(opt_offset[i], opt_offset[i], opt_size[i], 0); else walk_task(opt_offset[i], opt_size[i]); if (opt_mark_idle) mark_page_idle(0); close(kpageflags_fd); } /* * user interface */ static const char *page_flag_type(uint64_t flag) { if (flag & KPF_HACKERS_BITS) return "(r)"; if (flag & KPF_OVERLOADED_BITS) return "(o)"; return " "; } static void usage(void) { size_t i, j; printf( "page-types [options]\n" " -r|--raw Raw mode, for kernel developers\n" " -d|--describe flags Describe flags\n" " -a|--addr addr-spec Walk a range of pages\n" " -b|--bits bits-spec Walk pages with specified bits\n" " -c|--cgroup path|@inode Walk pages within memory cgroup\n" " -p|--pid pid Walk process address space\n" " -f|--file filename Walk file address space\n" " -i|--mark-idle Mark pages idle\n" " -l|--list Show page details in ranges\n" " -L|--list-each Show page details one by one\n" " -C|--list-cgroup Show cgroup inode for pages\n" " -M|--list-mapcnt Show page map count\n" " -N|--no-summary Don't show summary info\n" " -X|--hwpoison hwpoison pages\n" " -x|--unpoison unpoison pages\n" " -F|--kpageflags filename kpageflags file to parse\n" " -h|--help Show this usage message\n" "flags:\n" " 0x10 bitfield format, e.g.\n" " anon bit-name, e.g.\n" " 0x10,anon comma-separated list, e.g.\n" "addr-spec:\n" " N one page at offset N (unit: pages)\n" " N+M pages range from N to N+M-1\n" " N,M pages range from N to M-1\n" " N, pages range from N to end\n" " ,M pages range from 0 to M-1\n" "bits-spec:\n" " bit1,bit2 (flags & (bit1|bit2)) != 0\n" " bit1,bit2=bit1 (flags & (bit1|bit2)) == bit1\n" " bit1,~bit2 (flags & (bit1|bit2)) == bit1\n" " =bit1,bit2 flags == (bit1|bit2)\n" "bit-names:\n" ); for (i = 0, j = 0; i < ARRAY_SIZE(page_flag_names); i++) { if (!page_flag_names[i]) continue; printf("%16s%s", page_flag_names[i] + 2, page_flag_type(1ULL << i)); if (++j > 3) { j = 0; putchar('\n'); } } printf("\n " "(r) raw mode bits (o) overloaded bits\n"); } static unsigned long long parse_number(const char *str) { unsigned long long n; n = strtoll(str, NULL, 0); if (n == 0 && str[0] != '0') fatal("invalid name or number: %s\n", str); return n; } static void parse_pid(const char *str) { FILE *file; char buf[5000]; opt_pid = parse_number(str); sprintf(buf, "/proc/%d/pagemap", opt_pid); pagemap_fd = checked_open(buf, O_RDONLY); sprintf(buf, "/proc/%d/maps", opt_pid); file = fopen(buf, "r"); if (!file) { perror(buf); exit(EXIT_FAILURE); } while (fgets(buf, sizeof(buf), file) != NULL) { unsigned long vm_start; unsigned long vm_end; unsigned long long pgoff; int major, minor; char r, w, x, s; unsigned long ino; int n; n = sscanf(buf, "%lx-%lx %c%c%c%c %llx %x:%x %lu", &vm_start, &vm_end, &r, &w, &x, &s, &pgoff, &major, &minor, &ino); if (n < 10) { fprintf(stderr, "unexpected line: %s\n", buf); continue; } pg_start[nr_vmas] = vm_start / page_size; pg_end[nr_vmas] = vm_end / page_size; if (++nr_vmas >= MAX_VMAS) { fprintf(stderr, "too many VMAs\n"); break; } } fclose(file); } static void show_file(const char *name, const struct stat *st) { unsigned long long size = st->st_size; char atime[64], mtime[64]; long now = time(NULL); printf("%s\tInode: %u\tSize: %llu (%llu pages)\n", name, (unsigned)st->st_ino, size, (size + page_size - 1) / page_size); strftime(atime, sizeof(atime), "%c", localtime(&st->st_atime)); strftime(mtime, sizeof(mtime), "%c", localtime(&st->st_mtime)); printf("Modify: %s (%ld seconds ago)\nAccess: %s (%ld seconds ago)\n", mtime, now - st->st_mtime, atime, now - st->st_atime); } static sigjmp_buf sigbus_jmp; static void * volatile sigbus_addr; static void sigbus_handler(int sig, siginfo_t *info, void *ucontex) { (void)sig; (void)ucontex; sigbus_addr = info ? info->si_addr : NULL; siglongjmp(sigbus_jmp, 1); } static struct sigaction sigbus_action = { .sa_sigaction = sigbus_handler, .sa_flags = SA_SIGINFO, }; static void walk_file_range(const char *name, int fd, unsigned long off, unsigned long end) { uint8_t vec[PAGEMAP_BATCH]; uint64_t buf[PAGEMAP_BATCH], flags; uint64_t cgroup = 0; uint64_t mapcnt = 0; unsigned long nr_pages, pfn, i; ssize_t len; void *ptr; int first = 1; for (; off < end; off += len) { nr_pages = (end - off + page_size - 1) / page_size; if (nr_pages > PAGEMAP_BATCH) nr_pages = PAGEMAP_BATCH; len = nr_pages * page_size; ptr = mmap(NULL, len, PROT_READ, MAP_SHARED, fd, off); if (ptr == MAP_FAILED) fatal("mmap failed: %s", name); /* determine cached pages */ if (mincore(ptr, len, vec)) fatal("mincore failed: %s", name); /* turn off readahead */ if (madvise(ptr, len, MADV_RANDOM)) fatal("madvice failed: %s", name); if (sigsetjmp(sigbus_jmp, 1)) { end = off + sigbus_addr ? sigbus_addr - ptr : 0; fprintf(stderr, "got sigbus at offset %lld: %s\n", (long long)end, name); goto got_sigbus; } /* populate ptes */ for (i = 0; i < nr_pages ; i++) { if (vec[i] & 1) (void)*(volatile int *)(ptr + i * page_size); } got_sigbus: /* turn off harvesting reference bits */ if (madvise(ptr, len, MADV_SEQUENTIAL)) fatal("madvice failed: %s", name); if (pagemap_read(buf, (unsigned long)ptr / page_size, nr_pages) != nr_pages) fatal("cannot read pagemap"); munmap(ptr, len); for (i = 0; i < nr_pages; i++) { pfn = pagemap_pfn(buf[i]); if (!pfn) continue; if (!kpageflags_read(&flags, pfn, 1)) continue; if (!kpagecgroup_read(&cgroup, pfn, 1)) fatal("kpagecgroup_read failed"); if (!kpagecount_read(&mapcnt, pfn, 1)) fatal("kpagecount_read failed"); if (first && opt_list) { first = 0; flush_page_range(); } add_page(off / page_size + i, pfn, flags, cgroup, mapcnt, buf[i]); } } } static void walk_file(const char *name, const struct stat *st) { int i; int fd; fd = checked_open(name, O_RDONLY|O_NOATIME|O_NOFOLLOW); if (!nr_addr_ranges) add_addr_range(0, st->st_size / page_size); for (i = 0; i < nr_addr_ranges; i++) walk_file_range(name, fd, opt_offset[i] * page_size, (opt_offset[i] + opt_size[i]) * page_size); close(fd); } int walk_tree(const char *name, const struct stat *st, int type, struct FTW *f) { (void)f; switch (type) { case FTW_F: if (S_ISREG(st->st_mode)) walk_file(name, st); break; case FTW_DNR: fprintf(stderr, "cannot read dir: %s\n", name); break; } return 0; } struct stat st; static void walk_page_cache(void) { kpageflags_fd = checked_open(opt_kpageflags, O_RDONLY); pagemap_fd = checked_open("/proc/self/pagemap", O_RDONLY); sigaction(SIGBUS, &sigbus_action, NULL); if (stat(opt_file, &st)) fatal("stat failed: %s\n", opt_file); if (S_ISREG(st.st_mode)) { walk_file(opt_file, &st); } else if (S_ISDIR(st.st_mode)) { /* do not follow symlinks and mountpoints */ if (nftw(opt_file, walk_tree, 64, FTW_MOUNT | FTW_PHYS) < 0) fatal("nftw failed: %s\n", opt_file); } else fatal("unhandled file type: %s\n", opt_file); close(kpageflags_fd); close(pagemap_fd); signal(SIGBUS, SIG_DFL); } static void parse_file(const char *name) { opt_file = name; } static void parse_cgroup(const char *path) { if (path[0] == '@') { opt_cgroup = parse_number(path + 1); return; } struct stat st; if (stat(path, &st)) fatal("stat failed: %s: %m\n", path); if (!S_ISDIR(st.st_mode)) fatal("cgroup supposed to be a directory: %s\n", path); opt_cgroup = st.st_ino; } static void parse_addr_range(const char *optarg) { unsigned long offset; unsigned long size; char *p; p = strchr(optarg, ','); if (!p) p = strchr(optarg, '+'); if (p == optarg) { offset = 0; size = parse_number(p + 1); } else if (p) { offset = parse_number(optarg); if (p[1] == '\0') size = ULONG_MAX; else { size = parse_number(p + 1); if (*p == ',') { if (size < offset) fatal("invalid range: %lu,%lu\n", offset, size); size -= offset; } } } else { offset = parse_number(optarg); size = 1; } add_addr_range(offset, size); } static void add_bits_filter(uint64_t mask, uint64_t bits) { if (nr_bit_filters >= MAX_BIT_FILTERS) fatal("too much bit filters\n"); opt_mask[nr_bit_filters] = mask; opt_bits[nr_bit_filters] = bits; nr_bit_filters++; } static uint64_t parse_flag_name(const char *str, int len) { size_t i; if (!*str || !len) return 0; if (len <= 8 && !strncmp(str, "compound", len)) return BITS_COMPOUND; for (i = 0; i < ARRAY_SIZE(page_flag_names); i++) { if (!page_flag_names[i]) continue; if (!strncmp(str, page_flag_names[i] + 2, len)) return 1ULL << i; } return parse_number(str); } static uint64_t parse_flag_names(const char *str, int all) { const char *p = str; uint64_t flags = 0; while (1) { if (*p == ',' || *p == '=' || *p == '\0') { if ((*str != '~') || (*str == '~' && all && *++str)) flags |= parse_flag_name(str, p - str); if (*p != ',') break; str = p + 1; } p++; } return flags; } static void parse_bits_mask(const char *optarg) { uint64_t mask; uint64_t bits; const char *p; p = strchr(optarg, '='); if (p == optarg) { mask = KPF_ALL_BITS; bits = parse_flag_names(p + 1, 0); } else if (p) { mask = parse_flag_names(optarg, 0); bits = parse_flag_names(p + 1, 0); } else if (strchr(optarg, '~')) { mask = parse_flag_names(optarg, 1); bits = parse_flag_names(optarg, 0); } else { mask = parse_flag_names(optarg, 0); bits = KPF_ALL_BITS; } add_bits_filter(mask, bits); } static void parse_kpageflags(const char *name) { opt_kpageflags = name; } static void describe_flags(const char *optarg) { uint64_t flags = parse_flag_names(optarg, 0); printf("0x%016llx\t%s\t%s\n", (unsigned long long)flags, page_flag_name(flags), page_flag_longname(flags)); } static const struct option opts[] = { { "raw" , 0, NULL, 'r' }, { "pid" , 1, NULL, 'p' }, { "file" , 1, NULL, 'f' }, { "addr" , 1, NULL, 'a' }, { "bits" , 1, NULL, 'b' }, { "cgroup" , 1, NULL, 'c' }, { "describe" , 1, NULL, 'd' }, { "mark-idle" , 0, NULL, 'i' }, { "list" , 0, NULL, 'l' }, { "list-each" , 0, NULL, 'L' }, { "list-cgroup", 0, NULL, 'C' }, { "list-mapcnt", 0, NULL, 'M' }, { "no-summary", 0, NULL, 'N' }, { "hwpoison" , 0, NULL, 'X' }, { "unpoison" , 0, NULL, 'x' }, { "kpageflags", 0, NULL, 'F' }, { "help" , 0, NULL, 'h' }, { NULL , 0, NULL, 0 } }; int main(int argc, char *argv[]) { int c; page_size = getpagesize(); while ((c = getopt_long(argc, argv, "rp:f:a:b:d:c:CilLMNXxF:h", opts, NULL)) != -1) { switch (c) { case 'r': opt_raw = 1; break; case 'p': parse_pid(optarg); break; case 'f': parse_file(optarg); break; case 'a': parse_addr_range(optarg); break; case 'b': parse_bits_mask(optarg); break; case 'c': parse_cgroup(optarg); break; case 'C': opt_list_cgroup = 1; break; case 'd': describe_flags(optarg); exit(0); case 'i': opt_mark_idle = 1; break; case 'l': opt_list = 1; break; case 'L': opt_list = 2; break; case 'M': opt_list_mapcnt = 1; break; case 'N': opt_no_summary = 1; break; case 'X': opt_hwpoison = 1; prepare_hwpoison_fd(); break; case 'x': opt_unpoison = 1; prepare_hwpoison_fd(); break; case 'F': parse_kpageflags(optarg); break; case 'h': usage(); exit(0); default: usage(); exit(1); } } if (!opt_kpageflags) opt_kpageflags = PROC_KPAGEFLAGS; if (opt_cgroup || opt_list_cgroup) kpagecgroup_fd = checked_open(PROC_KPAGECGROUP, O_RDONLY); if (opt_list && opt_list_mapcnt) kpagecount_fd = checked_open(PROC_KPAGECOUNT, O_RDONLY); if (opt_mark_idle) page_idle_fd = checked_open(SYS_KERNEL_MM_PAGE_IDLE, O_RDWR); if (opt_list && opt_pid) printf("voffset\t"); if (opt_list && opt_file) printf("foffset\t"); if (opt_list && opt_list_cgroup) printf("cgroup\t"); if (opt_list && opt_list_mapcnt) printf("map-cnt\t"); if (opt_list == 1) printf("offset\tlen\tflags\n"); if (opt_list == 2) printf("offset\tflags\n"); if (opt_file) walk_page_cache(); else walk_addr_ranges(); if (opt_list == 1) flush_page_range(); if (opt_no_summary) return 0; if (opt_list) printf("\n\n"); if (opt_file) { show_file(opt_file, &st); printf("\n"); } show_summary(); if (opt_list_mapcnt) close(kpagecount_fd); if (page_idle_fd >= 0) close(page_idle_fd); return 0; }