From: Qi Zheng <zhengqi.arch@bytedance.com>
To: akpm@linux-foundation.org, tglx@linutronix.de,
hannes@cmpxchg.org, mhocko@kernel.org, vdavydov.dev@gmail.com,
kirill.shutemov@linux.intel.com, mika.penttila@nextfour.com,
david@redhat.com
Cc: linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org,
linux-mm@kvack.org, songmuchun@bytedance.com,
Qi Zheng <zhengqi.arch@bytedance.com>
Subject: [PATCH v1 1/2] mm: introduce pmd_install() helper
Date: Sat, 28 Aug 2021 12:23:05 +0800 [thread overview]
Message-ID: <20210828042306.42886-2-zhengqi.arch@bytedance.com> (raw)
In-Reply-To: <20210828042306.42886-1-zhengqi.arch@bytedance.com>
Currently we have three times the same few lines repeated in the
code. Deduplicate them by newly introduced pmd_install() helper.
Signed-off-by: Qi Zheng <zhengqi.arch@bytedance.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
---
include/linux/mm.h | 1 +
mm/filemap.c | 11 ++---------
mm/memory.c | 34 ++++++++++++++++------------------
3 files changed, 19 insertions(+), 27 deletions(-)
diff --git a/include/linux/mm.h b/include/linux/mm.h
index a3cc83d64564..0af420a7e382 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -2463,6 +2463,7 @@ static inline spinlock_t *pud_lock(struct mm_struct *mm, pud_t *pud)
return ptl;
}
+extern void pmd_install(struct mm_struct *mm, pmd_t *pmd, pgtable_t *pte);
extern void __init pagecache_init(void);
extern void __init free_area_init_memoryless_node(int nid);
extern void free_initmem(void);
diff --git a/mm/filemap.c b/mm/filemap.c
index c90b6e4984c9..923cbba1bf37 100644
--- a/mm/filemap.c
+++ b/mm/filemap.c
@@ -3209,15 +3209,8 @@ static bool filemap_map_pmd(struct vm_fault *vmf, struct page *page)
}
}
- if (pmd_none(*vmf->pmd)) {
- vmf->ptl = pmd_lock(mm, vmf->pmd);
- if (likely(pmd_none(*vmf->pmd))) {
- mm_inc_nr_ptes(mm);
- pmd_populate(mm, vmf->pmd, vmf->prealloc_pte);
- vmf->prealloc_pte = NULL;
- }
- spin_unlock(vmf->ptl);
- }
+ if (pmd_none(*vmf->pmd))
+ pmd_install(mm, vmf->pmd, &vmf->prealloc_pte);
/* See comment in handle_pte_fault() */
if (pmd_devmap_trans_unstable(vmf->pmd)) {
diff --git a/mm/memory.c b/mm/memory.c
index 39e7a1495c3c..ef7b1762e996 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -433,9 +433,20 @@ void free_pgtables(struct mmu_gather *tlb, struct vm_area_struct *vma,
}
}
+void pmd_install(struct mm_struct *mm, pmd_t *pmd, pgtable_t *pte)
+{
+ spinlock_t *ptl = pmd_lock(mm, pmd);
+
+ if (likely(pmd_none(*pmd))) { /* Has another populated it ? */
+ mm_inc_nr_ptes(mm);
+ pmd_populate(mm, pmd, *pte);
+ *pte = NULL;
+ }
+ spin_unlock(ptl);
+}
+
int __pte_alloc(struct mm_struct *mm, pmd_t *pmd)
{
- spinlock_t *ptl;
pgtable_t new = pte_alloc_one(mm);
if (!new)
return -ENOMEM;
@@ -455,13 +466,7 @@ int __pte_alloc(struct mm_struct *mm, pmd_t *pmd)
*/
smp_wmb(); /* Could be smp_wmb__xxx(before|after)_spin_lock */
- ptl = pmd_lock(mm, pmd);
- if (likely(pmd_none(*pmd))) { /* Has another populated it ? */
- mm_inc_nr_ptes(mm);
- pmd_populate(mm, pmd, new);
- new = NULL;
- }
- spin_unlock(ptl);
+ pmd_install(mm, pmd, &new);
if (new)
pte_free(mm, new);
return 0;
@@ -4027,17 +4032,10 @@ vm_fault_t finish_fault(struct vm_fault *vmf)
return ret;
}
- if (vmf->prealloc_pte) {
- vmf->ptl = pmd_lock(vma->vm_mm, vmf->pmd);
- if (likely(pmd_none(*vmf->pmd))) {
- mm_inc_nr_ptes(vma->vm_mm);
- pmd_populate(vma->vm_mm, vmf->pmd, vmf->prealloc_pte);
- vmf->prealloc_pte = NULL;
- }
- spin_unlock(vmf->ptl);
- } else if (unlikely(pte_alloc(vma->vm_mm, vmf->pmd))) {
+ if (vmf->prealloc_pte)
+ pmd_install(vma->vm_mm, vmf->pmd, &vmf->prealloc_pte);
+ else if (unlikely(pte_alloc(vma->vm_mm, vmf->pmd)))
return VM_FAULT_OOM;
- }
}
/* See comment in handle_pte_fault() */
--
2.11.0
next prev parent reply other threads:[~2021-08-28 4:23 UTC|newest]
Thread overview: 8+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-08-28 4:23 [PATCH v1 0/2] Do some code cleanups related to mm Qi Zheng
2021-08-28 4:23 ` Qi Zheng [this message]
2021-08-28 5:25 ` [PATCH v1 1/2] mm: introduce pmd_install() helper Muchun Song
2021-08-28 4:23 ` [PATCH v1 2/2] mm: remove redundant smp_wmb() Qi Zheng
2021-08-31 10:02 ` David Hildenbrand
2021-08-31 12:36 ` Qi Zheng
2021-08-31 10:20 ` Vlastimil Babka
2021-08-31 12:52 ` Qi Zheng
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20210828042306.42886-2-zhengqi.arch@bytedance.com \
--to=zhengqi.arch@bytedance.com \
--cc=akpm@linux-foundation.org \
--cc=david@redhat.com \
--cc=hannes@cmpxchg.org \
--cc=kirill.shutemov@linux.intel.com \
--cc=linux-doc@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-mm@kvack.org \
--cc=mhocko@kernel.org \
--cc=mika.penttila@nextfour.com \
--cc=songmuchun@bytedance.com \
--cc=tglx@linutronix.de \
--cc=vdavydov.dev@gmail.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).