/
task_mmu.c
2034 lines (1752 loc) · 49.2 KB
/
task_mmu.c
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// SPDX-License-Identifier: GPL-2.0
#include <linux/pagewalk.h>
#include <linux/mm_inline.h>
#include <linux/hugetlb.h>
#include <linux/huge_mm.h>
#include <linux/mount.h>
#include <linux/seq_file.h>
#include <linux/highmem.h>
#include <linux/ptrace.h>
#include <linux/slab.h>
#include <linux/pagemap.h>
#include <linux/mempolicy.h>
#include <linux/rmap.h>
#include <linux/swap.h>
#include <linux/sched/mm.h>
#include <linux/swapops.h>
#include <linux/mmu_notifier.h>
#include <linux/page_idle.h>
#include <linux/shmem_fs.h>
#include <linux/uaccess.h>
#include <linux/pkeys.h>
#include <asm/elf.h>
#include <asm/tlb.h>
#include <asm/tlbflush.h>
#include "internal.h"
#define SEQ_PUT_DEC(str, val) \
seq_put_decimal_ull_width(m, str, (val) << (PAGE_SHIFT-10), 8)
void task_mem(struct seq_file *m, struct mm_struct *mm)
{
unsigned long text, lib, swap, anon, file, shmem;
unsigned long hiwater_vm, total_vm, hiwater_rss, total_rss;
anon = get_mm_counter(mm, MM_ANONPAGES);
file = get_mm_counter(mm, MM_FILEPAGES);
shmem = get_mm_counter(mm, MM_SHMEMPAGES);
/*
* Note: to minimize their overhead, mm maintains hiwater_vm and
* hiwater_rss only when about to *lower* total_vm or rss. Any
* collector of these hiwater stats must therefore get total_vm
* and rss too, which will usually be the higher. Barriers? not
* worth the effort, such snapshots can always be inconsistent.
*/
hiwater_vm = total_vm = mm->total_vm;
if (hiwater_vm < mm->hiwater_vm)
hiwater_vm = mm->hiwater_vm;
hiwater_rss = total_rss = anon + file + shmem;
if (hiwater_rss < mm->hiwater_rss)
hiwater_rss = mm->hiwater_rss;
/* split executable areas between text and lib */
text = PAGE_ALIGN(mm->end_code) - (mm->start_code & PAGE_MASK);
text = min(text, mm->exec_vm << PAGE_SHIFT);
lib = (mm->exec_vm << PAGE_SHIFT) - text;
swap = get_mm_counter(mm, MM_SWAPENTS);
SEQ_PUT_DEC("VmPeak:\t", hiwater_vm);
SEQ_PUT_DEC(" kB\nVmSize:\t", total_vm);
SEQ_PUT_DEC(" kB\nVmLck:\t", mm->locked_vm);
SEQ_PUT_DEC(" kB\nVmPin:\t", atomic64_read(&mm->pinned_vm));
SEQ_PUT_DEC(" kB\nVmHWM:\t", hiwater_rss);
SEQ_PUT_DEC(" kB\nVmRSS:\t", total_rss);
SEQ_PUT_DEC(" kB\nRssAnon:\t", anon);
SEQ_PUT_DEC(" kB\nRssFile:\t", file);
SEQ_PUT_DEC(" kB\nRssShmem:\t", shmem);
SEQ_PUT_DEC(" kB\nVmData:\t", mm->data_vm);
SEQ_PUT_DEC(" kB\nVmStk:\t", mm->stack_vm);
seq_put_decimal_ull_width(m,
" kB\nVmExe:\t", text >> 10, 8);
seq_put_decimal_ull_width(m,
" kB\nVmLib:\t", lib >> 10, 8);
seq_put_decimal_ull_width(m,
" kB\nVmPTE:\t", mm_pgtables_bytes(mm) >> 10, 8);
SEQ_PUT_DEC(" kB\nVmSwap:\t", swap);
seq_puts(m, " kB\n");
hugetlb_report_usage(m, mm);
}
#undef SEQ_PUT_DEC
unsigned long task_vsize(struct mm_struct *mm)
{
return PAGE_SIZE * mm->total_vm;
}
unsigned long task_statm(struct mm_struct *mm,
unsigned long *shared, unsigned long *text,
unsigned long *data, unsigned long *resident)
{
*shared = get_mm_counter(mm, MM_FILEPAGES) +
get_mm_counter(mm, MM_SHMEMPAGES);
*text = (PAGE_ALIGN(mm->end_code) - (mm->start_code & PAGE_MASK))
>> PAGE_SHIFT;
*data = mm->data_vm + mm->stack_vm;
*resident = *shared + get_mm_counter(mm, MM_ANONPAGES);
return mm->total_vm;
}
#ifdef CONFIG_NUMA
/*
* Save get_task_policy() for show_numa_map().
*/
static void hold_task_mempolicy(struct proc_maps_private *priv)
{
struct task_struct *task = priv->task;
task_lock(task);
priv->task_mempolicy = get_task_policy(task);
mpol_get(priv->task_mempolicy);
task_unlock(task);
}
static void release_task_mempolicy(struct proc_maps_private *priv)
{
mpol_put(priv->task_mempolicy);
}
#else
static void hold_task_mempolicy(struct proc_maps_private *priv)
{
}
static void release_task_mempolicy(struct proc_maps_private *priv)
{
}
#endif
static struct vm_area_struct *proc_get_vma(struct proc_maps_private *priv,
loff_t *ppos)
{
struct vm_area_struct *vma = vma_next(&priv->iter);
if (vma) {
*ppos = vma->vm_start;
} else {
*ppos = -2UL;
vma = get_gate_vma(priv->mm);
}
return vma;
}
static void *m_start(struct seq_file *m, loff_t *ppos)
{
struct proc_maps_private *priv = m->private;
unsigned long last_addr = *ppos;
struct mm_struct *mm;
/* See m_next(). Zero at the start or after lseek. */
if (last_addr == -1UL)
return NULL;
priv->task = get_proc_task(priv->inode);
if (!priv->task)
return ERR_PTR(-ESRCH);
mm = priv->mm;
if (!mm || !mmget_not_zero(mm)) {
put_task_struct(priv->task);
priv->task = NULL;
return NULL;
}
if (mmap_read_lock_killable(mm)) {
mmput(mm);
put_task_struct(priv->task);
priv->task = NULL;
return ERR_PTR(-EINTR);
}
vma_iter_init(&priv->iter, mm, last_addr);
hold_task_mempolicy(priv);
if (last_addr == -2UL)
return get_gate_vma(mm);
return proc_get_vma(priv, ppos);
}
static void *m_next(struct seq_file *m, void *v, loff_t *ppos)
{
if (*ppos == -2UL) {
*ppos = -1UL;
return NULL;
}
return proc_get_vma(m->private, ppos);
}
static void m_stop(struct seq_file *m, void *v)
{
struct proc_maps_private *priv = m->private;
struct mm_struct *mm = priv->mm;
if (!priv->task)
return;
release_task_mempolicy(priv);
mmap_read_unlock(mm);
mmput(mm);
put_task_struct(priv->task);
priv->task = NULL;
}
static int proc_maps_open(struct inode *inode, struct file *file,
const struct seq_operations *ops, int psize)
{
struct proc_maps_private *priv = __seq_open_private(file, ops, psize);
if (!priv)
return -ENOMEM;
priv->inode = inode;
priv->mm = proc_mem_open(inode, PTRACE_MODE_READ);
if (IS_ERR(priv->mm)) {
int err = PTR_ERR(priv->mm);
seq_release_private(inode, file);
return err;
}
return 0;
}
static int proc_map_release(struct inode *inode, struct file *file)
{
struct seq_file *seq = file->private_data;
struct proc_maps_private *priv = seq->private;
if (priv->mm)
mmdrop(priv->mm);
return seq_release_private(inode, file);
}
static int do_maps_open(struct inode *inode, struct file *file,
const struct seq_operations *ops)
{
return proc_maps_open(inode, file, ops,
sizeof(struct proc_maps_private));
}
/*
* Indicate if the VMA is a stack for the given task; for
* /proc/PID/maps that is the stack of the main task.
*/
static int is_stack(struct vm_area_struct *vma)
{
/*
* We make no effort to guess what a given thread considers to be
* its "stack". It's not even well-defined for programs written
* languages like Go.
*/
return vma->vm_start <= vma->vm_mm->start_stack &&
vma->vm_end >= vma->vm_mm->start_stack;
}
static void show_vma_header_prefix(struct seq_file *m,
unsigned long start, unsigned long end,
vm_flags_t flags, unsigned long long pgoff,
dev_t dev, unsigned long ino)
{
seq_setwidth(m, 25 + sizeof(void *) * 6 - 1);
seq_put_hex_ll(m, NULL, start, 8);
seq_put_hex_ll(m, "-", end, 8);
seq_putc(m, ' ');
seq_putc(m, flags & VM_READ ? 'r' : '-');
seq_putc(m, flags & VM_WRITE ? 'w' : '-');
seq_putc(m, flags & VM_EXEC ? 'x' : '-');
seq_putc(m, flags & VM_MAYSHARE ? 's' : 'p');
seq_put_hex_ll(m, " ", pgoff, 8);
seq_put_hex_ll(m, " ", MAJOR(dev), 2);
seq_put_hex_ll(m, ":", MINOR(dev), 2);
seq_put_decimal_ull(m, " ", ino);
seq_putc(m, ' ');
}
static void
show_map_vma(struct seq_file *m, struct vm_area_struct *vma)
{
struct anon_vma_name *anon_name = NULL;
struct mm_struct *mm = vma->vm_mm;
struct file *file = vma->vm_file;
vm_flags_t flags = vma->vm_flags;
unsigned long ino = 0;
unsigned long long pgoff = 0;
unsigned long start, end;
dev_t dev = 0;
const char *name = NULL;
if (file) {
struct inode *inode = file_inode(vma->vm_file);
dev = inode->i_sb->s_dev;
ino = inode->i_ino;
pgoff = ((loff_t)vma->vm_pgoff) << PAGE_SHIFT;
}
start = vma->vm_start;
end = vma->vm_end;
show_vma_header_prefix(m, start, end, flags, pgoff, dev, ino);
if (mm)
anon_name = anon_vma_name(vma);
/*
* Print the dentry name for named mappings, and a
* special [heap] marker for the heap:
*/
if (file) {
seq_pad(m, ' ');
/*
* If user named this anon shared memory via
* prctl(PR_SET_VMA ..., use the provided name.
*/
if (anon_name)
seq_printf(m, "[anon_shmem:%s]", anon_name->name);
else
seq_file_path(m, file, "\n");
goto done;
}
if (vma->vm_ops && vma->vm_ops->name) {
name = vma->vm_ops->name(vma);
if (name)
goto done;
}
name = arch_vma_name(vma);
if (!name) {
if (!mm) {
name = "[vdso]";
goto done;
}
if (vma->vm_start <= mm->brk &&
vma->vm_end >= mm->start_brk) {
name = "[heap]";
goto done;
}
if (is_stack(vma)) {
name = "[stack]";
goto done;
}
if (anon_name) {
seq_pad(m, ' ');
seq_printf(m, "[anon:%s]", anon_name->name);
}
}
done:
if (name) {
seq_pad(m, ' ');
seq_puts(m, name);
}
seq_putc(m, '\n');
}
static int show_map(struct seq_file *m, void *v)
{
show_map_vma(m, v);
return 0;
}
static const struct seq_operations proc_pid_maps_op = {
.start = m_start,
.next = m_next,
.stop = m_stop,
.show = show_map
};
static int pid_maps_open(struct inode *inode, struct file *file)
{
return do_maps_open(inode, file, &proc_pid_maps_op);
}
const struct file_operations proc_pid_maps_operations = {
.open = pid_maps_open,
.read = seq_read,
.llseek = seq_lseek,
.release = proc_map_release,
};
/*
* Proportional Set Size(PSS): my share of RSS.
*
* PSS of a process is the count of pages it has in memory, where each
* page is divided by the number of processes sharing it. So if a
* process has 1000 pages all to itself, and 1000 shared with one other
* process, its PSS will be 1500.
*
* To keep (accumulated) division errors low, we adopt a 64bit
* fixed-point pss counter to minimize division errors. So (pss >>
* PSS_SHIFT) would be the real byte count.
*
* A shift of 12 before division means (assuming 4K page size):
* - 1M 3-user-pages add up to 8KB errors;
* - supports mapcount up to 2^24, or 16M;
* - supports PSS up to 2^52 bytes, or 4PB.
*/
#define PSS_SHIFT 12
#ifdef CONFIG_PROC_PAGE_MONITOR
struct mem_size_stats {
unsigned long resident;
unsigned long shared_clean;
unsigned long shared_dirty;
unsigned long private_clean;
unsigned long private_dirty;
unsigned long referenced;
unsigned long anonymous;
unsigned long lazyfree;
unsigned long anonymous_thp;
unsigned long shmem_thp;
unsigned long file_thp;
unsigned long swap;
unsigned long shared_hugetlb;
unsigned long private_hugetlb;
u64 pss;
u64 pss_anon;
u64 pss_file;
u64 pss_shmem;
u64 pss_dirty;
u64 pss_locked;
u64 swap_pss;
};
static void smaps_page_accumulate(struct mem_size_stats *mss,
struct page *page, unsigned long size, unsigned long pss,
bool dirty, bool locked, bool private)
{
mss->pss += pss;
if (PageAnon(page))
mss->pss_anon += pss;
else if (PageSwapBacked(page))
mss->pss_shmem += pss;
else
mss->pss_file += pss;
if (locked)
mss->pss_locked += pss;
if (dirty || PageDirty(page)) {
mss->pss_dirty += pss;
if (private)
mss->private_dirty += size;
else
mss->shared_dirty += size;
} else {
if (private)
mss->private_clean += size;
else
mss->shared_clean += size;
}
}
static void smaps_account(struct mem_size_stats *mss, struct page *page,
bool compound, bool young, bool dirty, bool locked,
bool migration)
{
int i, nr = compound ? compound_nr(page) : 1;
unsigned long size = nr * PAGE_SIZE;
/*
* First accumulate quantities that depend only on |size| and the type
* of the compound page.
*/
if (PageAnon(page)) {
mss->anonymous += size;
if (!PageSwapBacked(page) && !dirty && !PageDirty(page))
mss->lazyfree += size;
}
mss->resident += size;
/* Accumulate the size in pages that have been accessed. */
if (young || page_is_young(page) || PageReferenced(page))
mss->referenced += size;
/*
* Then accumulate quantities that may depend on sharing, or that may
* differ page-by-page.
*
* page_count(page) == 1 guarantees the page is mapped exactly once.
* If any subpage of the compound page mapped with PTE it would elevate
* page_count().
*
* The page_mapcount() is called to get a snapshot of the mapcount.
* Without holding the page lock this snapshot can be slightly wrong as
* we cannot always read the mapcount atomically. It is not safe to
* call page_mapcount() even with PTL held if the page is not mapped,
* especially for migration entries. Treat regular migration entries
* as mapcount == 1.
*/
if ((page_count(page) == 1) || migration) {
smaps_page_accumulate(mss, page, size, size << PSS_SHIFT, dirty,
locked, true);
return;
}
for (i = 0; i < nr; i++, page++) {
int mapcount = page_mapcount(page);
unsigned long pss = PAGE_SIZE << PSS_SHIFT;
if (mapcount >= 2)
pss /= mapcount;
smaps_page_accumulate(mss, page, PAGE_SIZE, pss, dirty, locked,
mapcount < 2);
}
}
#ifdef CONFIG_SHMEM
static int smaps_pte_hole(unsigned long addr, unsigned long end,
__always_unused int depth, struct mm_walk *walk)
{
struct mem_size_stats *mss = walk->private;
struct vm_area_struct *vma = walk->vma;
mss->swap += shmem_partial_swap_usage(walk->vma->vm_file->f_mapping,
linear_page_index(vma, addr),
linear_page_index(vma, end));
return 0;
}
#else
#define smaps_pte_hole NULL
#endif /* CONFIG_SHMEM */
static void smaps_pte_hole_lookup(unsigned long addr, struct mm_walk *walk)
{
#ifdef CONFIG_SHMEM
if (walk->ops->pte_hole) {
/* depth is not used */
smaps_pte_hole(addr, addr + PAGE_SIZE, 0, walk);
}
#endif
}
static void smaps_pte_entry(pte_t *pte, unsigned long addr,
struct mm_walk *walk)
{
struct mem_size_stats *mss = walk->private;
struct vm_area_struct *vma = walk->vma;
bool locked = !!(vma->vm_flags & VM_LOCKED);
struct page *page = NULL;
bool migration = false, young = false, dirty = false;
if (pte_present(*pte)) {
page = vm_normal_page(vma, addr, *pte);
young = pte_young(*pte);
dirty = pte_dirty(*pte);
} else if (is_swap_pte(*pte)) {
swp_entry_t swpent = pte_to_swp_entry(*pte);
if (!non_swap_entry(swpent)) {
int mapcount;
mss->swap += PAGE_SIZE;
mapcount = swp_swapcount(swpent);
if (mapcount >= 2) {
u64 pss_delta = (u64)PAGE_SIZE << PSS_SHIFT;
do_div(pss_delta, mapcount);
mss->swap_pss += pss_delta;
} else {
mss->swap_pss += (u64)PAGE_SIZE << PSS_SHIFT;
}
} else if (is_pfn_swap_entry(swpent)) {
if (is_migration_entry(swpent))
migration = true;
page = pfn_swap_entry_to_page(swpent);
}
} else {
smaps_pte_hole_lookup(addr, walk);
return;
}
if (!page)
return;
smaps_account(mss, page, false, young, dirty, locked, migration);
}
#ifdef CONFIG_TRANSPARENT_HUGEPAGE
static void smaps_pmd_entry(pmd_t *pmd, unsigned long addr,
struct mm_walk *walk)
{
struct mem_size_stats *mss = walk->private;
struct vm_area_struct *vma = walk->vma;
bool locked = !!(vma->vm_flags & VM_LOCKED);
struct page *page = NULL;
bool migration = false;
if (pmd_present(*pmd)) {
/* FOLL_DUMP will return -EFAULT on huge zero page */
page = follow_trans_huge_pmd(vma, addr, pmd, FOLL_DUMP);
} else if (unlikely(thp_migration_supported() && is_swap_pmd(*pmd))) {
swp_entry_t entry = pmd_to_swp_entry(*pmd);
if (is_migration_entry(entry)) {
migration = true;
page = pfn_swap_entry_to_page(entry);
}
}
if (IS_ERR_OR_NULL(page))
return;
if (PageAnon(page))
mss->anonymous_thp += HPAGE_PMD_SIZE;
else if (PageSwapBacked(page))
mss->shmem_thp += HPAGE_PMD_SIZE;
else if (is_zone_device_page(page))
/* pass */;
else
mss->file_thp += HPAGE_PMD_SIZE;
smaps_account(mss, page, true, pmd_young(*pmd), pmd_dirty(*pmd),
locked, migration);
}
#else
static void smaps_pmd_entry(pmd_t *pmd, unsigned long addr,
struct mm_walk *walk)
{
}
#endif
static int smaps_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end,
struct mm_walk *walk)
{
struct vm_area_struct *vma = walk->vma;
pte_t *pte;
spinlock_t *ptl;
ptl = pmd_trans_huge_lock(pmd, vma);
if (ptl) {
smaps_pmd_entry(pmd, addr, walk);
spin_unlock(ptl);
goto out;
}
if (pmd_trans_unstable(pmd))
goto out;
/*
* The mmap_lock held all the way back in m_start() is what
* keeps khugepaged out of here and from collapsing things
* in here.
*/
pte = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl);
for (; addr != end; pte++, addr += PAGE_SIZE)
smaps_pte_entry(pte, addr, walk);
pte_unmap_unlock(pte - 1, ptl);
out:
cond_resched();
return 0;
}
static void show_smap_vma_flags(struct seq_file *m, struct vm_area_struct *vma)
{
/*
* Don't forget to update Documentation/ on changes.
*/
static const char mnemonics[BITS_PER_LONG][2] = {
/*
* In case if we meet a flag we don't know about.
*/
[0 ... (BITS_PER_LONG-1)] = "??",
[ilog2(VM_READ)] = "rd",
[ilog2(VM_WRITE)] = "wr",
[ilog2(VM_EXEC)] = "ex",
[ilog2(VM_SHARED)] = "sh",
[ilog2(VM_MAYREAD)] = "mr",
[ilog2(VM_MAYWRITE)] = "mw",
[ilog2(VM_MAYEXEC)] = "me",
[ilog2(VM_MAYSHARE)] = "ms",
[ilog2(VM_GROWSDOWN)] = "gd",
[ilog2(VM_PFNMAP)] = "pf",
[ilog2(VM_LOCKED)] = "lo",
[ilog2(VM_IO)] = "io",
[ilog2(VM_SEQ_READ)] = "sr",
[ilog2(VM_RAND_READ)] = "rr",
[ilog2(VM_DONTCOPY)] = "dc",
[ilog2(VM_DONTEXPAND)] = "de",
[ilog2(VM_LOCKONFAULT)] = "lf",
[ilog2(VM_ACCOUNT)] = "ac",
[ilog2(VM_NORESERVE)] = "nr",
[ilog2(VM_HUGETLB)] = "ht",
[ilog2(VM_SYNC)] = "sf",
[ilog2(VM_ARCH_1)] = "ar",
[ilog2(VM_WIPEONFORK)] = "wf",
[ilog2(VM_DONTDUMP)] = "dd",
#ifdef CONFIG_ARM64_BTI
[ilog2(VM_ARM64_BTI)] = "bt",
#endif
#ifdef CONFIG_MEM_SOFT_DIRTY
[ilog2(VM_SOFTDIRTY)] = "sd",
#endif
[ilog2(VM_MIXEDMAP)] = "mm",
[ilog2(VM_HUGEPAGE)] = "hg",
[ilog2(VM_NOHUGEPAGE)] = "nh",
[ilog2(VM_MERGEABLE)] = "mg",
[ilog2(VM_UFFD_MISSING)]= "um",
[ilog2(VM_UFFD_WP)] = "uw",
#ifdef CONFIG_ARM64_MTE
[ilog2(VM_MTE)] = "mt",
[ilog2(VM_MTE_ALLOWED)] = "",
#endif
#ifdef CONFIG_ARCH_HAS_PKEYS
/* These come out via ProtectionKey: */
[ilog2(VM_PKEY_BIT0)] = "",
[ilog2(VM_PKEY_BIT1)] = "",
[ilog2(VM_PKEY_BIT2)] = "",
[ilog2(VM_PKEY_BIT3)] = "",
#if VM_PKEY_BIT4
[ilog2(VM_PKEY_BIT4)] = "",
#endif
#endif /* CONFIG_ARCH_HAS_PKEYS */
#ifdef CONFIG_HAVE_ARCH_USERFAULTFD_MINOR
[ilog2(VM_UFFD_MINOR)] = "ui",
#endif /* CONFIG_HAVE_ARCH_USERFAULTFD_MINOR */
};
size_t i;
seq_puts(m, "VmFlags: ");
for (i = 0; i < BITS_PER_LONG; i++) {
if (!mnemonics[i][0])
continue;
if (vma->vm_flags & (1UL << i)) {
seq_putc(m, mnemonics[i][0]);
seq_putc(m, mnemonics[i][1]);
seq_putc(m, ' ');
}
}
seq_putc(m, '\n');
}
#ifdef CONFIG_HUGETLB_PAGE
static int smaps_hugetlb_range(pte_t *pte, unsigned long hmask,
unsigned long addr, unsigned long end,
struct mm_walk *walk)
{
struct mem_size_stats *mss = walk->private;
struct vm_area_struct *vma = walk->vma;
struct page *page = NULL;
if (pte_present(*pte)) {
page = vm_normal_page(vma, addr, *pte);
} else if (is_swap_pte(*pte)) {
swp_entry_t swpent = pte_to_swp_entry(*pte);
if (is_pfn_swap_entry(swpent))
page = pfn_swap_entry_to_page(swpent);
}
if (page) {
if (page_mapcount(page) >= 2 || hugetlb_pmd_shared(pte))
mss->shared_hugetlb += huge_page_size(hstate_vma(vma));
else
mss->private_hugetlb += huge_page_size(hstate_vma(vma));
}
return 0;
}
#else
#define smaps_hugetlb_range NULL
#endif /* HUGETLB_PAGE */
static const struct mm_walk_ops smaps_walk_ops = {
.pmd_entry = smaps_pte_range,
.hugetlb_entry = smaps_hugetlb_range,
};
static const struct mm_walk_ops smaps_shmem_walk_ops = {
.pmd_entry = smaps_pte_range,
.hugetlb_entry = smaps_hugetlb_range,
.pte_hole = smaps_pte_hole,
};
/*
* Gather mem stats from @vma with the indicated beginning
* address @start, and keep them in @mss.
*
* Use vm_start of @vma as the beginning address if @start is 0.
*/
static void smap_gather_stats(struct vm_area_struct *vma,
struct mem_size_stats *mss, unsigned long start)
{
const struct mm_walk_ops *ops = &smaps_walk_ops;
/* Invalid start */
if (start >= vma->vm_end)
return;
#ifdef CONFIG_SHMEM
if (vma->vm_file && shmem_mapping(vma->vm_file->f_mapping)) {
/*
* For shared or readonly shmem mappings we know that all
* swapped out pages belong to the shmem object, and we can
* obtain the swap value much more efficiently. For private
* writable mappings, we might have COW pages that are
* not affected by the parent swapped out pages of the shmem
* object, so we have to distinguish them during the page walk.
* Unless we know that the shmem object (or the part mapped by
* our VMA) has no swapped out pages at all.
*/
unsigned long shmem_swapped = shmem_swap_usage(vma);
if (!start && (!shmem_swapped || (vma->vm_flags & VM_SHARED) ||
!(vma->vm_flags & VM_WRITE))) {
mss->swap += shmem_swapped;
} else {
ops = &smaps_shmem_walk_ops;
}
}
#endif
/* mmap_lock is held in m_start */
if (!start)
walk_page_vma(vma, ops, mss);
else
walk_page_range(vma->vm_mm, start, vma->vm_end, ops, mss);
}
#define SEQ_PUT_DEC(str, val) \
seq_put_decimal_ull_width(m, str, (val) >> 10, 8)
/* Show the contents common for smaps and smaps_rollup */
static void __show_smap(struct seq_file *m, const struct mem_size_stats *mss,
bool rollup_mode)
{
SEQ_PUT_DEC("Rss: ", mss->resident);
SEQ_PUT_DEC(" kB\nPss: ", mss->pss >> PSS_SHIFT);
SEQ_PUT_DEC(" kB\nPss_Dirty: ", mss->pss_dirty >> PSS_SHIFT);
if (rollup_mode) {
/*
* These are meaningful only for smaps_rollup, otherwise two of
* them are zero, and the other one is the same as Pss.
*/
SEQ_PUT_DEC(" kB\nPss_Anon: ",
mss->pss_anon >> PSS_SHIFT);
SEQ_PUT_DEC(" kB\nPss_File: ",
mss->pss_file >> PSS_SHIFT);
SEQ_PUT_DEC(" kB\nPss_Shmem: ",
mss->pss_shmem >> PSS_SHIFT);
}
SEQ_PUT_DEC(" kB\nShared_Clean: ", mss->shared_clean);
SEQ_PUT_DEC(" kB\nShared_Dirty: ", mss->shared_dirty);
SEQ_PUT_DEC(" kB\nPrivate_Clean: ", mss->private_clean);
SEQ_PUT_DEC(" kB\nPrivate_Dirty: ", mss->private_dirty);
SEQ_PUT_DEC(" kB\nReferenced: ", mss->referenced);
SEQ_PUT_DEC(" kB\nAnonymous: ", mss->anonymous);
SEQ_PUT_DEC(" kB\nLazyFree: ", mss->lazyfree);
SEQ_PUT_DEC(" kB\nAnonHugePages: ", mss->anonymous_thp);
SEQ_PUT_DEC(" kB\nShmemPmdMapped: ", mss->shmem_thp);
SEQ_PUT_DEC(" kB\nFilePmdMapped: ", mss->file_thp);
SEQ_PUT_DEC(" kB\nShared_Hugetlb: ", mss->shared_hugetlb);
seq_put_decimal_ull_width(m, " kB\nPrivate_Hugetlb: ",
mss->private_hugetlb >> 10, 7);
SEQ_PUT_DEC(" kB\nSwap: ", mss->swap);
SEQ_PUT_DEC(" kB\nSwapPss: ",
mss->swap_pss >> PSS_SHIFT);
SEQ_PUT_DEC(" kB\nLocked: ",
mss->pss_locked >> PSS_SHIFT);
seq_puts(m, " kB\n");
}
static int show_smap(struct seq_file *m, void *v)
{
struct vm_area_struct *vma = v;
struct mem_size_stats mss;
memset(&mss, 0, sizeof(mss));
smap_gather_stats(vma, &mss, 0);
show_map_vma(m, vma);
SEQ_PUT_DEC("Size: ", vma->vm_end - vma->vm_start);
SEQ_PUT_DEC(" kB\nKernelPageSize: ", vma_kernel_pagesize(vma));
SEQ_PUT_DEC(" kB\nMMUPageSize: ", vma_mmu_pagesize(vma));
seq_puts(m, " kB\n");
__show_smap(m, &mss, false);
seq_printf(m, "THPeligible: %d\n",
hugepage_vma_check(vma, vma->vm_flags, true, false, true));
if (arch_pkeys_enabled())
seq_printf(m, "ProtectionKey: %8u\n", vma_pkey(vma));
show_smap_vma_flags(m, vma);
return 0;
}
static int show_smaps_rollup(struct seq_file *m, void *v)
{
struct proc_maps_private *priv = m->private;
struct mem_size_stats mss;
struct mm_struct *mm = priv->mm;
struct vm_area_struct *vma;
unsigned long vma_start = 0, last_vma_end = 0;
int ret = 0;
MA_STATE(mas, &mm->mm_mt, 0, 0);
priv->task = get_proc_task(priv->inode);
if (!priv->task)
return -ESRCH;
if (!mm || !mmget_not_zero(mm)) {
ret = -ESRCH;
goto out_put_task;
}
memset(&mss, 0, sizeof(mss));
ret = mmap_read_lock_killable(mm);
if (ret)
goto out_put_mm;
hold_task_mempolicy(priv);
vma = mas_find(&mas, ULONG_MAX);
if (unlikely(!vma))
goto empty_set;
vma_start = vma->vm_start;
do {
smap_gather_stats(vma, &mss, 0);
last_vma_end = vma->vm_end;
/*
* Release mmap_lock temporarily if someone wants to
* access it for write request.
*/
if (mmap_lock_is_contended(mm)) {
mas_pause(&mas);
mmap_read_unlock(mm);
ret = mmap_read_lock_killable(mm);
if (ret) {
release_task_mempolicy(priv);
goto out_put_mm;
}
/*
* After dropping the lock, there are four cases to
* consider. See the following example for explanation.
*
* +------+------+-----------+
* | VMA1 | VMA2 | VMA3 |
* +------+------+-----------+
* | | | |
* 4k 8k 16k 400k
*
* Suppose we drop the lock after reading VMA2 due to
* contention, then we get:
*
* last_vma_end = 16k
*
* 1) VMA2 is freed, but VMA3 exists:
*
* find_vma(mm, 16k - 1) will return VMA3.
* In this case, just continue from VMA3.
*
* 2) VMA2 still exists:
*
* find_vma(mm, 16k - 1) will return VMA2.
* Iterate the loop like the original one.
*
* 3) No more VMAs can be found:
*
* find_vma(mm, 16k - 1) will return NULL.
* No more things to do, just break.
*
* 4) (last_vma_end - 1) is the middle of a vma (VMA'):
*
* find_vma(mm, 16k - 1) will return VMA' whose range
* contains last_vma_end.
* Iterate VMA' from last_vma_end.
*/
vma = mas_find(&mas, ULONG_MAX);
/* Case 3 above */
if (!vma)
break;
/* Case 1 above */
if (vma->vm_start >= last_vma_end)
continue;
/* Case 4 above */
if (vma->vm_end > last_vma_end)
smap_gather_stats(vma, &mss, last_vma_end);
}
/* Case 2 above */
} while ((vma = mas_find(&mas, ULONG_MAX)) != NULL);
empty_set:
show_vma_header_prefix(m, vma_start, last_vma_end, 0, 0, 0, 0);
seq_pad(m, ' ');
seq_puts(m, "[rollup]\n");
__show_smap(m, &mss, true);
release_task_mempolicy(priv);
mmap_read_unlock(mm);
out_put_mm:
mmput(mm);
out_put_task:
put_task_struct(priv->task);
priv->task = NULL;