The patch titled
page-types: add feature for walking process address space
has been added to the -mm tree. Its filename is
page-types-add-feature-for-walking-process-address-space.patch
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*** Remember to use Documentation/SubmitChecklist when testing your code ***
See http://userweb.kernel.org/~akpm/stuff/added-to-mm.txt to find
out what to do about this
The current -mm tree may be found at http://userweb.kernel.org/~akpm/mmotm/
------------------------------------------------------
Subject: page-types: add feature for walking process address space
From: Wu Fengguang <fengguang.wu@xxxxxxxxx>
Introduce "-p|--pid <pid>" for walking the process address space. The
default action is to walk raw memory PFNs.
Both the virtual address and physhcal address of each present pages will be listed:
# ./tools/vm/page-types -lp $$ | head -3
voffset offset len flags
400 11bebe 1 __RU_lA____M______________________
402 11bebc 1 __RU_lA____M______________________
Note that voffset/offset/len are now showed as hex numbers.
Cc: Andi Kleen <andi@xxxxxxxxxxxxxx>
Signed-off-by: Wu Fengguang <fengguang.wu@xxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
Documentation/vm/page-types.c | 200 ++++++++++++++++++++++++++++----
1 file changed, 180 insertions(+), 20 deletions(-)
diff -puN Documentation/vm/page-types.c~page-types-add-feature-for-walking-process-address-space Documentation/vm/page-types.c
--- a/Documentation/vm/page-types.c~page-types-add-feature-for-walking-process-address-space
+++ a/Documentation/vm/page-types.c
@@ -5,6 +5,7 @@
* Copyright (C) 2009 Wu Fengguang <fengguang.wu@xxxxxxxxx>
*/
+#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
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
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
}
}
+
+#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(c
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");
_
Patches currently in -mm which might be from fengguang.wu@xxxxxxxxx are
linux-next.patch
mm-memory-failure-remove-config_unevictable_lru-config-option.patch
readahead-add-blk_run_backing_dev.patch
readahead-add-blk_run_backing_dev-fix.patch
readahead-add-blk_run_backing_dev-fix-fix-2.patch
mm-clean-up-page_remove_rmap.patch
mm-oom-analysis-add-per-zone-statistics-to-show_free_areas.patch
mm-oom-analysis-add-buffer-cache-information-to-show_free_areas.patch
mm-oom-analysis-add-shmem-vmstat.patch
mm-shrink_inactive_list-nr_scan-accounting-fix-fix.patch
mm-vmstat-add-isolate-pages.patch
mm-vmstat-add-isolate-pages-fix.patch
vmscan-throttle-direct-reclaim-when-too-many-pages-are-isolated-already.patch
mm-remove-__addsub_zone_page_state.patch
mm-count-only-reclaimable-lru-pages-v2.patch
vmscan-move-clearpageactive-from-move_active_pages-to-shrink_active_list.patch
vmscan-kill-unnecessary-page-flag-test.patch
vmscan-kill-unnecessary-prefetch.patch
ksm-add-mmu_notifier-set_pte_at_notify.patch
ksm-first-tidy-up-madvise_vma.patch
ksm-define-madv_mergeable-and-madv_unmergeable.patch
ksm-the-mm-interface-to-ksm.patch
ksm-no-debug-in-page_dup_rmap.patch
ksm-identify-pageksm-pages.patch
ksm-kernel-samepage-merging.patch
ksm-prevent-mremap-move-poisoning.patch
ksm-change-copyright-message.patch
ksm-change-ksm-nice-level-to-be-5.patch
mm-do-batched-scans-for-mem_cgroup.patch
mm-vsmcan-check-shrink_active_list-sc-isolate_pages-return-value.patch
documentation-vm-gitignore-add-page-types.patch
page-types-add-feature-for-walking-process-address-space.patch
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