From: Anshuman Khandual <khandual@linux.vnet.ibm.com>
To: linuxppc-dev@lists.ozlabs.org
Cc: mpe@ellerman.id.au, aneesh.kumar@linux.ibm.com, benh@kernel.crashing.org
Subject: [PATCH] powerpc/mm: Initialize kernel pagetable memory for PTE fragments
Date: Wed, 20 Jun 2018 09:10:42 +0530 [thread overview]
Message-ID: <20180620034042.17470-1-khandual@linux.vnet.ibm.com> (raw)
Kernel pagetable pages for PTE fragments never go through the standard init
sequence which can cause inaccuracies in utilization statistics reported at
places like /proc and /sysfs interfaces etc. Also the allocated page misses
out on pagetable lock and page flag init as well. Fix it by making sure all
pages allocated for either user process or kernel PTE fragments go through
same initialization.
Signed-off-by: Anshuman Khandual <khandual@linux.vnet.ibm.com>
---
arch/powerpc/mm/pgtable-book3s64.c | 24 +++++++++++-------------
1 file changed, 11 insertions(+), 13 deletions(-)
diff --git a/arch/powerpc/mm/pgtable-book3s64.c b/arch/powerpc/mm/pgtable-book3s64.c
index c1f4ca4..1e8f67c 100644
--- a/arch/powerpc/mm/pgtable-book3s64.c
+++ b/arch/powerpc/mm/pgtable-book3s64.c
@@ -335,23 +335,21 @@ static pte_t *get_pte_from_cache(struct mm_struct *mm)
static pte_t *__alloc_for_ptecache(struct mm_struct *mm, int kernel)
{
+ gfp_t gfp_mask = PGALLOC_GFP;
void *ret = NULL;
struct page *page;
- if (!kernel) {
- page = alloc_page(PGALLOC_GFP | __GFP_ACCOUNT);
- if (!page)
- return NULL;
- if (!pgtable_page_ctor(page)) {
- __free_page(page);
- return NULL;
- }
- } else {
- page = alloc_page(PGALLOC_GFP);
- if (!page)
- return NULL;
- }
+ if (!kernel)
+ gfp_mask |= __GFP_ACCOUNT;
+ page = alloc_page(gfp_mask);
+ if (!page)
+ return NULL;
+
+ if (!pgtable_page_ctor(page)) {
+ __free_page(page);
+ return NULL;
+ }
ret = page_address(page);
/*
--
1.8.3.1
reply other threads:[~2018-06-20 3:40 UTC|newest]
Thread overview: [no followups] expand[flat|nested] mbox.gz Atom feed
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=20180620034042.17470-1-khandual@linux.vnet.ibm.com \
--to=khandual@linux.vnet.ibm.com \
--cc=aneesh.kumar@linux.ibm.com \
--cc=benh@kernel.crashing.org \
--cc=linuxppc-dev@lists.ozlabs.org \
--cc=mpe@ellerman.id.au \
/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).