From: Vijay Balakrishna <vijayb@linux.microsoft.com>
To: Andrew Morton <akpm@linux-foundation.org>,
"Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>,
Oleg Nesterov <oleg@redhat.com>, Song Liu <songliubraving@fb.com>,
Andrea Arcangeli <aarcange@redhat.com>,
Pavel Tatashin <pasha.tatashin@soleen.com>,
Vijay Balakrishna <vijayb@linux.microsoft.com>,
Michal Hocko <mhocko@suse.com>, Allen Pais <apais@microsoft.com>
Cc: linux-kernel@vger.kernel.org, linux-mm@kvack.org
Subject: [v2 2/2] mm: khugepaged: avoid overriding min_free_kbytes set by user
Date: Tue, 15 Sep 2020 14:10:58 -0700 [thread overview]
Message-ID: <1600204258-13683-2-git-send-email-vijayb@linux.microsoft.com> (raw)
In-Reply-To: <1600204258-13683-1-git-send-email-vijayb@linux.microsoft.com>
set_recommended_min_free_kbytes need to honor min_free_kbytes set by the
user. Post start-of-day THP enable or memory hotplug operations can
lose user specified min_free_kbytes, in particular when it is higher than
calculated recommended value. Also modifying "recommended_min" variable
type to "int" from "unsigned long" to avoid undesired result noticed
during testing. It is due to comparing "unsigned long" with "int" type.
Signed-off-by: Vijay Balakrishna <vijayb@linux.microsoft.com>
Cc: stable@vger.kernel.org
Reviewed-by: Pavel Tatashin <pasha.tatashin@soleen.com>
---
mm/khugepaged.c | 8 ++++----
1 file changed, 4 insertions(+), 4 deletions(-)
diff --git a/mm/khugepaged.c b/mm/khugepaged.c
index 4f7107476a6f..b4b753ba411a 100644
--- a/mm/khugepaged.c
+++ b/mm/khugepaged.c
@@ -2253,7 +2253,7 @@ static void set_recommended_min_free_kbytes(void)
{
struct zone *zone;
int nr_zones = 0;
- unsigned long recommended_min;
+ int recommended_min;
for_each_populated_zone(zone) {
/*
@@ -2280,12 +2280,12 @@ static void set_recommended_min_free_kbytes(void)
/* don't ever allow to reserve more than 5% of the lowmem */
recommended_min = min(recommended_min,
- (unsigned long) nr_free_buffer_pages() / 20);
+ (int) nr_free_buffer_pages() / 20);
recommended_min <<= (PAGE_SHIFT-10);
- if (recommended_min > min_free_kbytes) {
+ if (recommended_min > user_min_free_kbytes) {
if (user_min_free_kbytes >= 0)
- pr_info("raising min_free_kbytes from %d to %lu to help transparent hugepage allocations\n",
+ pr_info("raising min_free_kbytes from %d to %d to help transparent hugepage allocations\n",
min_free_kbytes, recommended_min);
min_free_kbytes = recommended_min;
--
2.28.0
next prev parent reply other threads:[~2020-09-15 21:14 UTC|newest]
Thread overview: 7+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-09-15 21:10 [v2 1/2] mm: khugepaged: recalculate min_free_kbytes after memory hotplug as expected by khugepaged Vijay Balakrishna
2020-09-15 21:10 ` Vijay Balakrishna [this message]
2020-09-16 7:59 ` [v2 2/2] mm: khugepaged: avoid overriding min_free_kbytes set by user Michal Hocko
2020-09-16 19:18 ` Vijay Balakrishna
2020-09-21 12:54 ` Sasha Levin
2020-09-16 7:47 ` [v2 1/2] mm: khugepaged: recalculate min_free_kbytes after memory hotplug as expected by khugepaged Michal Hocko
2020-09-21 12:55 ` Sasha Levin
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=1600204258-13683-2-git-send-email-vijayb@linux.microsoft.com \
--to=vijayb@linux.microsoft.com \
--cc=aarcange@redhat.com \
--cc=akpm@linux-foundation.org \
--cc=apais@microsoft.com \
--cc=kirill.shutemov@linux.intel.com \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-mm@kvack.org \
--cc=mhocko@suse.com \
--cc=oleg@redhat.com \
--cc=pasha.tatashin@soleen.com \
--cc=songliubraving@fb.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).