[PATCH v1 3/3] tools/vm/page-types.c: support swap entry

From: Naoya Horiguchi
Date: Thu Feb 04 2016 - 02:09:13 EST


/proc/pid/pagemap (pte_to_pagemap_entry() internally) already reports about
swap entry, so let's make the in-kernel utility aware of it.

Signed-off-by: Naoya Horiguchi <n-horiguchi@xxxxxxxxxxxxx>
---
tools/vm/page-types.c | 30 +++++++++++++++++++++++++++++-
1 file changed, 29 insertions(+), 1 deletion(-)

diff --git v4.5-rc2-mmotm-2016-02-02-17-08/tools/vm/page-types.c v4.5-rc2-mmotm-2016-02-02-17-08_patched/tools/vm/page-types.c
index 5a60162..ec62ab4 100644
--- v4.5-rc2-mmotm-2016-02-02-17-08/tools/vm/page-types.c
+++ v4.5-rc2-mmotm-2016-02-02-17-08_patched/tools/vm/page-types.c
@@ -61,6 +61,8 @@
#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)
@@ -92,7 +94,8 @@
#define KPF_SLOB_FREE 49
#define KPF_SLUB_FROZEN 50
#define KPF_SLUB_DEBUG 51
-#define KPF_FILE 62
+#define KPF_FILE 61
+#define KPF_SWAP 62
#define KPF_MMAP_EXCLUSIVE 63

#define KPF_ALL_BITS ((uint64_t)~0ULL)
@@ -146,6 +149,7 @@ static const char * const page_flag_names[] = {
[KPF_SLUB_DEBUG] = "E:slub_debug",

[KPF_FILE] = "F:file",
+ [KPF_SWAP] = "w:swap",
[KPF_MMAP_EXCLUSIVE] = "1:mmap_exclusive",
};

@@ -297,6 +301,10 @@ static unsigned long pagemap_pfn(uint64_t val)
return pfn;
}

+static unsigned long pagemap_swap_offset(uint64_t val)
+{
+ return val & PM_SWAP ? PM_SWAP_OFFSET(val) : 0;
+}

/*
* page flag names
@@ -452,6 +460,8 @@ static uint64_t expand_overloaded_flags(uint64_t flags, uint64_t pme)
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);

@@ -613,6 +623,22 @@ static void walk_pfn(unsigned long voffset,
}
}

+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_list == 1)
+ show_page_range(voffset, pagemap_swap_offset(pme), 1, flags);
+ else if (opt_list == 2)
+ show_page(voffset, pagemap_swap_offset(pme), flags);
+
+ nr_pages[hash_slot(flags)]++;
+ total_pages++;
+}
+
#define PAGEMAP_BATCH (64 << 10)
static void walk_vma(unsigned long index, unsigned long count)
{
@@ -632,6 +658,8 @@ static void walk_vma(unsigned long index, unsigned long count)
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;
--
2.7.0