diff options
Diffstat (limited to 'Documentation')
| -rw-r--r-- | Documentation/vm/page-types.c | 200 |
1 files changed, 180 insertions, 20 deletions
diff --git a/Documentation/vm/page-types.c b/Documentation/vm/page-types.c index 3eda8ea0085..fa1a30d9e9d 100644 --- a/Documentation/vm/page-types.c +++ b/Documentation/vm/page-types.c @@ -5,6 +5,7 @@ * Copyright (C) 2009 Wu Fengguang <fengguang.wu@intel.com> */ +#define _LARGEFILE64_SOURCE #include <stdio.h> #include <stdlib.h> #include <unistd.h> @@ -13,12 +14,33 @@ #include <string.h> #include <getopt.h> #include <limits.h> +#include <assert.h> #include <sys/types.h> #include <sys/errno.h> #include <sys/fcntl.h> /* + * pagemap kernel ABI bits + */ + +#define PM_ENTRY_BYTES sizeof(uint64_t) +#define PM_STATUS_BITS 3 +#define PM_STATUS_OFFSET (64 - PM_STATUS_BITS) +#define PM_STATUS_MASK (((1LL << PM_STATUS_BITS) - 1) << PM_STATUS_OFFSET) +#define PM_STATUS(nr) (((nr) << PM_STATUS_OFFSET) & PM_STATUS_MASK) +#define PM_PSHIFT_BITS 6 +#define PM_PSHIFT_OFFSET (PM_STATUS_OFFSET - PM_PSHIFT_BITS) +#define PM_PSHIFT_MASK (((1LL << PM_PSHIFT_BITS) - 1) << PM_PSHIFT_OFFSET) +#define PM_PSHIFT(x) (((u64) (x) << PM_PSHIFT_OFFSET) & PM_PSHIFT_MASK) +#define PM_PFRAME_MASK ((1LL << PM_PSHIFT_OFFSET) - 1) +#define PM_PFRAME(x) ((x) & PM_PFRAME_MASK) + +#define PM_PRESENT PM_STATUS(4LL) +#define PM_SWAP PM_STATUS(2LL) + + +/* * kernel page flags */ @@ -126,6 +148,14 @@ 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]; +static unsigned long voffset; + +static int pagemap_fd; + #define MAX_BIT_FILTERS 64 static int nr_bit_filters; static uint64_t opt_mask[MAX_BIT_FILTERS]; @@ -135,7 +165,6 @@ static int page_size; #define PAGES_BATCH (64 << 10) /* 64k pages */ static int kpageflags_fd; -static uint64_t kpageflags_buf[KPF_BYTES * PAGES_BATCH]; #define HASH_SHIFT 13 #define HASH_SIZE (1 << HASH_SHIFT) @@ -158,6 +187,11 @@ static uint64_t page_flags[HASH_SIZE]; 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; @@ -224,26 +258,34 @@ static char *page_flag_longname(uint64_t flags) static void show_page_range(unsigned long offset, uint64_t flags) { static uint64_t flags0; + static unsigned long voff; static unsigned long index; static unsigned long count; - if (flags == flags0 && offset == index + count) { + if (flags == flags0 && offset == index + count && + (!opt_pid || voffset == voff + count)) { count++; return; } - if (count) - printf("%lu\t%lu\t%s\n", + if (count) { + if (opt_pid) + printf("%lx\t", voff); + printf("%lx\t%lx\t%s\n", index, count, page_flag_name(flags0)); + } flags0 = flags; index = offset; + voff = voffset; count = 1; } static void show_page(unsigned long offset, uint64_t flags) { - printf("%lu\t%s\n", offset, page_flag_name(flags)); + if (opt_pid) + printf("%lx\t", voffset); + printf("%lx\t%s\n", offset, page_flag_name(flags)); } static void show_summary(void) @@ -383,6 +425,8 @@ static void walk_pfn(unsigned long index, unsigned long count) lseek(kpageflags_fd, index * KPF_BYTES, SEEK_SET); while (count) { + uint64_t kpageflags_buf[KPF_BYTES * PAGES_BATCH]; + batch = min_t(unsigned long, count, PAGES_BATCH); n = read(kpageflags_fd, kpageflags_buf, batch * KPF_BYTES); if (n == 0) @@ -404,6 +448,81 @@ static void walk_pfn(unsigned long index, unsigned long count) } } + +#define PAGEMAP_BATCH 4096 +static unsigned long task_pfn(unsigned long pgoff) +{ + static uint64_t buf[PAGEMAP_BATCH]; + static unsigned long start; + static long count; + uint64_t pfn; + + if (pgoff < start || pgoff >= start + count) { + if (lseek64(pagemap_fd, + (uint64_t)pgoff * PM_ENTRY_BYTES, + SEEK_SET) < 0) { + perror("pagemap seek"); + exit(EXIT_FAILURE); + } + count = read(pagemap_fd, buf, sizeof(buf)); + if (count == 0) + return 0; + if (count < 0) { + perror("pagemap read"); + exit(EXIT_FAILURE); + } + if (count % PM_ENTRY_BYTES) { + fatal("pagemap read not aligned.\n"); + exit(EXIT_FAILURE); + } + count /= PM_ENTRY_BYTES; + start = pgoff; + } + + pfn = buf[pgoff - start]; + if (pfn & PM_PRESENT) + pfn = PM_PFRAME(pfn); + else + pfn = 0; + + return pfn; +} + +static void walk_task(unsigned long index, unsigned long count) +{ + int i = 0; + const unsigned long end = index + count; + + while (index < end) { + + while (pg_end[i] <= index) + if (++i >= nr_vmas) + return; + if (pg_start[i] >= end) + return; + + voffset = max_t(unsigned long, pg_start[i], index); + index = min_t(unsigned long, pg_end[i], end); + + assert(voffset < index); + for (; voffset < index; voffset++) { + unsigned long pfn = task_pfn(voffset); + if (pfn) + walk_pfn(pfn, 1); + } + } +} + +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; @@ -415,10 +534,13 @@ static void walk_addr_ranges(void) } if (!nr_addr_ranges) - walk_pfn(0, ULONG_MAX); + add_addr_range(0, ULONG_MAX); for (i = 0; i < nr_addr_ranges; i++) - walk_pfn(opt_offset[i], opt_size[i]); + if (!opt_pid) + walk_pfn(opt_offset[i], opt_size[i]); + else + walk_task(opt_offset[i], opt_size[i]); close(kpageflags_fd); } @@ -446,8 +568,8 @@ static void usage(void) " -r|--raw Raw mode, for kernel developers\n" " -a|--addr addr-spec Walk a range of pages\n" " -b|--bits bits-spec Walk pages with specified bits\n" -#if 0 /* planned features */ " -p|--pid pid Walk process address space\n" +#if 0 /* planned features */ " -f|--file filename Walk file address space\n" #endif " -l|--list Show page details in ranges\n" @@ -459,7 +581,7 @@ static void usage(void) " 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\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" @@ -496,21 +618,57 @@ static unsigned long long parse_number(const char *str) static void parse_pid(const char *str) { + FILE *file; + char buf[5000]; + opt_pid = parse_number(str); -} -static void parse_file(const char *name) -{ + sprintf(buf, "/proc/%d/pagemap", opt_pid); + pagemap_fd = open(buf, O_RDONLY); + if (pagemap_fd < 0) { + perror(buf); + exit(EXIT_FAILURE); + } + + 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 add_addr_range(unsigned long offset, unsigned long size) +static void parse_file(const char *name) { - if (nr_addr_ranges >= MAX_ADDR_RANGES) - fatal("too much addr ranges\n"); - - opt_offset[nr_addr_ranges] = offset; - opt_size[nr_addr_ranges] = size; - nr_addr_ranges++; } static void parse_addr_range(const char *optarg) @@ -676,8 +834,10 @@ int main(int argc, char *argv[]) } } + if (opt_list && opt_pid) + printf("voffset\t"); if (opt_list == 1) - printf("offset\tcount\tflags\n"); + printf("offset\tlen\tflags\n"); if (opt_list == 2) printf("offset\tflags\n"); |