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mm/khugepaged: dedup and simplify hugepage alloc and charging

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The following code is duplicated in collapse_huge_page() and
collapse_file():

        gfp = alloc_hugepage_khugepaged_gfpmask() | __GFP_THISNODE;

	new_page = khugepaged_alloc_page(hpage, gfp, node);
        if (!new_page) {
                result = SCAN_ALLOC_HUGE_PAGE_FAIL;
                goto out;
        }

        if (unlikely(mem_cgroup_charge(page_folio(new_page), mm, gfp))) {
                result = SCAN_CGROUP_CHARGE_FAIL;
                goto out;
        }
        count_memcg_page_event(new_page, THP_COLLAPSE_ALLOC);

Also, "node" is passed as an argument to both collapse_huge_page() and
collapse_file() and obtained the same way, via
khugepaged_find_target_node().

Move all this into a new helper, alloc_charge_hpage(), and remove the
duplicate code from collapse_huge_page() and collapse_file().  Also,
simplify khugepaged_alloc_page() by returning a bool indicating allocation
success instead of a copy of the allocated struct page *.

Link: https://lkml.kernel.org/r/20220706235936.2197195-5-zokeefe@google.com
Signed-off-by: Zach O'Keefe <zokeefe@google.com>
Suggested-by: Peter Xu <peterx@redhat.com>
Acked-by: David Rientjes <rientjes@google.com>
Reviewed-by: Yang Shi <shy828301@gmail.com>
Cc: Alex Shi <alex.shi@linux.alibaba.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Axel Rasmussen <axelrasmussen@google.com>
Cc: Chris Kennelly <ckennelly@google.com>
Cc: Chris Zankel <chris@zankel.net>
Cc: David Hildenbrand <david@redhat.com>
Cc: Helge Deller <deller@gmx.de>
Cc: Hugh Dickins <hughd@google.com>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Miaohe Lin <linmiaohe@huawei.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Pasha Tatashin <pasha.tatashin@soleen.com>
Cc: Pavel Begunkov <asml.silence@gmail.com>
Cc: Rongwei Wang <rongwei.wang@linux.alibaba.com>
Cc: SeongJae Park <sj@kernel.org>
Cc: Song Liu <songliubraving@fb.com>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Zi Yan <ziy@nvidia.com>
Cc: Dan Carpenter <dan.carpenter@oracle.com>
Cc: "Souptick Joarder (HPE)" <jrdr.linux@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
This commit is contained in:
Zach O'Keefe 2022-07-06 16:59:22 -07:00 committed by Andrew Morton
parent 34d6b470ab
commit 9710a78ab2
1 changed files with 35 additions and 43 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

78
mm/khugepaged.c
View File

@ -813,19 +813,18 @@ static int khugepaged_find_target_node(struct collapse_control *cc)
}
#endif
static struct page *
khugepaged_alloc_page(struct page **hpage, gfp_t gfp, int node)
static bool khugepaged_alloc_page(struct page **hpage, gfp_t gfp, int node)
{
*hpage = __alloc_pages_node(node, gfp, HPAGE_PMD_ORDER);
if (unlikely(!*hpage)) {
count_vm_event(THP_COLLAPSE_ALLOC_FAILED);
*hpage = ERR_PTR(-ENOMEM);
return NULL;
return false;
}
prep_transhuge_page(*hpage);
count_vm_event(THP_COLLAPSE_ALLOC);
return *hpage;
return true;
}
/*
@ -923,10 +922,24 @@ static bool __collapse_huge_page_swapin(struct mm_struct *mm,
return true;
}
static void collapse_huge_page(struct mm_struct *mm,
unsigned long address,
struct page **hpage,
int node, int referenced, int unmapped)
static int alloc_charge_hpage(struct page **hpage, struct mm_struct *mm,
struct collapse_control *cc)
{
/* Only allocate from the target node */
gfp_t gfp = alloc_hugepage_khugepaged_gfpmask() | __GFP_THISNODE;
int node = khugepaged_find_target_node(cc);
if (!khugepaged_alloc_page(hpage, gfp, node))
return SCAN_ALLOC_HUGE_PAGE_FAIL;
if (unlikely(mem_cgroup_charge(page_folio(*hpage), mm, gfp)))
return SCAN_CGROUP_CHARGE_FAIL;
count_memcg_page_event(*hpage, THP_COLLAPSE_ALLOC);
return SCAN_SUCCEED;
}
static void collapse_huge_page(struct mm_struct *mm, unsigned long address,
struct page **hpage, int referenced,
int unmapped, struct collapse_control *cc)
{
LIST_HEAD(compound_pagelist);
pmd_t *pmd, _pmd;
@ -937,13 +950,9 @@ static void collapse_huge_page(struct mm_struct *mm,
int isolated = 0, result = 0;
struct vm_area_struct *vma;
struct mmu_notifier_range range;
gfp_t gfp;
VM_BUG_ON(address & ~HPAGE_PMD_MASK);
/* Only allocate from the target node */
gfp = alloc_hugepage_khugepaged_gfpmask() | __GFP_THISNODE;
/*
* Before allocating the hugepage, release the mmap_lock read lock.
* The allocation can take potentially a long time if it involves
@ -951,17 +960,12 @@ static void collapse_huge_page(struct mm_struct *mm,
* that. We will recheck the vma after taking it again in write mode.
*/
mmap_read_unlock(mm);
new_page = khugepaged_alloc_page(hpage, gfp, node);
if (!new_page) {
result = SCAN_ALLOC_HUGE_PAGE_FAIL;
goto out_nolock;
}
if (unlikely(mem_cgroup_charge(page_folio(new_page), mm, gfp))) {
result = SCAN_CGROUP_CHARGE_FAIL;
result = alloc_charge_hpage(hpage, mm, cc);
if (result != SCAN_SUCCEED)
goto out_nolock;
}
count_memcg_page_event(new_page, THP_COLLAPSE_ALLOC);
new_page = *hpage;
mmap_read_lock(mm);
result = hugepage_vma_revalidate(mm, address, &vma);
@ -1235,10 +1239,9 @@ static int khugepaged_scan_pmd(struct mm_struct *mm, struct vm_area_struct *vma,
out_unmap:
pte_unmap_unlock(pte, ptl);
if (ret) {
node = khugepaged_find_target_node(cc);
/* collapse_huge_page will return with the mmap_lock released */
collapse_huge_page(mm, address, hpage, node,
referenced, unmapped);
collapse_huge_page(mm, address, hpage, referenced, unmapped,
cc);
}
out:
trace_mm_khugepaged_scan_pmd(mm, page, writable, referenced,
@ -1506,7 +1509,7 @@ static void retract_page_tables(struct address_space *mapping, pgoff_t pgoff)
* @file: file that collapse on
* @start: collapse start address
* @hpage: new allocated huge page for collapse
* @node: appointed node the new huge page allocate from
* @cc: collapse context and scratchpad
*
* Basic scheme is simple, details are more complex:
* - allocate and lock a new huge page;
@ -1523,12 +1526,11 @@ static void retract_page_tables(struct address_space *mapping, pgoff_t pgoff)
* + restore gaps in the page cache;
* + unlock and free huge page;
*/
static void collapse_file(struct mm_struct *mm,
struct file *file, pgoff_t start,
struct page **hpage, int node)
static void collapse_file(struct mm_struct *mm, struct file *file,
pgoff_t start, struct page **hpage,
struct collapse_control *cc)
{
struct address_space *mapping = file->f_mapping;
gfp_t gfp;
struct page *new_page;
pgoff_t index, end = start + HPAGE_PMD_NR;
LIST_HEAD(pagelist);
@ -1540,20 +1542,11 @@ static void collapse_file(struct mm_struct *mm,
VM_BUG_ON(!IS_ENABLED(CONFIG_READ_ONLY_THP_FOR_FS) && !is_shmem);
VM_BUG_ON(start & (HPAGE_PMD_NR - 1));
/* Only allocate from the target node */
gfp = alloc_hugepage_khugepaged_gfpmask() | __GFP_THISNODE;
new_page = khugepaged_alloc_page(hpage, gfp, node);
if (!new_page) {
result = SCAN_ALLOC_HUGE_PAGE_FAIL;
result = alloc_charge_hpage(hpage, mm, cc);
if (result != SCAN_SUCCEED)
goto out;
}
if (unlikely(mem_cgroup_charge(page_folio(new_page), mm, gfp))) {
result = SCAN_CGROUP_CHARGE_FAIL;
goto out;
}
count_memcg_page_event(new_page, THP_COLLAPSE_ALLOC);
new_page = *hpage;
/*
* Ensure we have slots for all the pages in the range. This is
@ -1965,8 +1958,7 @@ static void khugepaged_scan_file(struct mm_struct *mm, struct file *file,
result = SCAN_EXCEED_NONE_PTE;
count_vm_event(THP_SCAN_EXCEED_NONE_PTE);
} else {
node = khugepaged_find_target_node(cc);
collapse_file(mm, file, start, hpage, node);
collapse_file(mm, file, start, hpage, cc);
}
}