From: Mel Gorman <mgorman@techsingularity.net>
To: Vlastimil Babka <vbabka@suse.cz>
Cc: Linux-MM <linux-mm@kvack.org>,
David Rientjes <rientjes@google.com>,
Andrea Arcangeli <aarcange@redhat.com>,
ying.huang@intel.com, kirill@shutemov.name,
Andrew Morton <akpm@linux-foundation.org>,
Linux List Kernel Mailing <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH 23/25] mm, compaction: Be selective about what pageblocks to clear skip hints
Date: Fri, 18 Jan 2019 14:10:45 +0000 [thread overview]
Message-ID: <20190118141045.GQ27437@techsingularity.net> (raw)
In-Reply-To: <73c2705a-ead3-614a-0364-458d919d8e13@suse.cz>
On Fri, Jan 18, 2019 at 01:55:24PM +0100, Vlastimil Babka wrote:
> > +static bool
> > +__reset_isolation_pfn(struct zone *zone, unsigned long pfn, bool check_source,
> > + bool check_target)
> > +{
> > + struct page *page = pfn_to_online_page(pfn);
> > + struct page *end_page;
> > +
> > + if (!page)
> > + return false;
> > + if (zone != page_zone(page))
> > + return false;
> > + if (pageblock_skip_persistent(page))
> > + return false;
> > +
> > + /*
> > + * If skip is already cleared do no further checking once the
> > + * restart points have been set.
> > + */
> > + if (check_source && check_target && !get_pageblock_skip(page))
> > + return true;
> > +
> > + /*
> > + * If clearing skip for the target scanner, do not select a
> > + * non-movable pageblock as the starting point.
> > + */
> > + if (!check_source && check_target &&
> > + get_pageblock_migratetype(page) != MIGRATE_MOVABLE)
> > + return false;
> > +
> > + /*
> > + * Only clear the hint if a sample indicates there is either a
> > + * free page or an LRU page in the block. One or other condition
> > + * is necessary for the block to be a migration source/target.
> > + */
> > + page = pfn_to_page(pageblock_start_pfn(pfn));
> > + if (zone != page_zone(page))
> > + return false;
> > + end_page = page + pageblock_nr_pages;
>
> Watch out for start pfn being invalid, and end_page being invalid or after zone end?
>
Yeah, it is possible there is no alignment on pageblock_nr_pages.
> > +
> > + do {
> > + if (check_source && PageLRU(page)) {
> > + clear_pageblock_skip(page);
> > + return true;
> > + }
> > +
> > + if (check_target && PageBuddy(page)) {
> > + clear_pageblock_skip(page);
> > + return true;
> > + }
> > +
> > + page += (1 << PAGE_ALLOC_COSTLY_ORDER);
>
> Also probably check pfn_valid_within() and page_zone?
>
Again yes. Holes could have been punched.
I've an updated version but I'll shove it through tests just to be sure.
> > + } while (page < end_page);
> > +
> > + return false;
> > +}
> > +
> > /*
> > * This function is called to clear all cached information on pageblocks that
> > * should be skipped for page isolation when the migrate and free page scanner
>
> ...
>
> > @@ -1193,7 +1273,7 @@ fast_isolate_freepages(struct compact_control *cc)
> > * If starting the scan, use a deeper search and use the highest
> > * PFN found if a suitable one is not found.
> > */
> > - if (cc->free_pfn == pageblock_start_pfn(zone_end_pfn(cc->zone) - 1)) {
> > + if (cc->free_pfn >= cc->zone->compact_init_free_pfn) {
> > limit = pageblock_nr_pages >> 1;
> > scan_start = true;
> > }
> > @@ -1338,7 +1418,6 @@ static void isolate_freepages(struct compact_control *cc)
> > unsigned long isolate_start_pfn; /* exact pfn we start at */
> > unsigned long block_end_pfn; /* end of current pageblock */
> > unsigned long low_pfn; /* lowest pfn scanner is able to scan */
> > - unsigned long nr_isolated;
> > struct list_head *freelist = &cc->freepages;
> > unsigned int stride;
> >
> > @@ -1374,6 +1453,8 @@ static void isolate_freepages(struct compact_control *cc)
> > block_end_pfn = block_start_pfn,
> > block_start_pfn -= pageblock_nr_pages,
> > isolate_start_pfn = block_start_pfn) {
> > + unsigned long nr_isolated;
>
> Unrelated cleanup? Nevermind.
>
I'll move the hunks to "mm, compaction: Sample pageblocks for free
pages" where they belong
--
Mel Gorman
SUSE Labs
next prev parent reply other threads:[~2019-01-18 14:10 UTC|newest]
Thread overview: 75+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-01-04 12:49 [PATCH 00/25] Increase success rates and reduce latency of compaction v2 Mel Gorman
2019-01-04 12:49 ` [PATCH 01/25] mm, compaction: Shrink compact_control Mel Gorman
2019-01-04 12:49 ` [PATCH 02/25] mm, compaction: Rearrange compact_control Mel Gorman
2019-01-04 12:49 ` [PATCH 03/25] mm, compaction: Remove last_migrated_pfn from compact_control Mel Gorman
2019-01-04 12:49 ` [PATCH 04/25] mm, compaction: Remove unnecessary zone parameter in some instances Mel Gorman
2019-01-15 11:43 ` Vlastimil Babka
2019-01-04 12:49 ` [PATCH 05/25] mm, compaction: Rename map_pages to split_map_pages Mel Gorman
2019-01-15 11:59 ` Vlastimil Babka
2019-01-04 12:49 ` [PATCH 06/25] mm, compaction: Skip pageblocks with reserved pages Mel Gorman
2019-01-15 12:10 ` Vlastimil Babka
2019-01-15 12:50 ` Mel Gorman
2019-01-16 9:42 ` Mel Gorman
2019-01-04 12:49 ` [PATCH 07/25] mm, migrate: Immediately fail migration of a page with no migration handler Mel Gorman
2019-01-04 12:49 ` [PATCH 08/25] mm, compaction: Always finish scanning of a full pageblock Mel Gorman
2019-01-04 12:49 ` [PATCH 09/25] mm, compaction: Use the page allocator bulk-free helper for lists of pages Mel Gorman
2019-01-15 12:39 ` Vlastimil Babka
2019-01-16 9:46 ` Mel Gorman
2019-01-04 12:49 ` [PATCH 10/25] mm, compaction: Ignore the fragmentation avoidance boost for isolation and compaction Mel Gorman
2019-01-15 13:18 ` Vlastimil Babka
2019-01-04 12:49 ` [PATCH 11/25] mm, compaction: Use free lists to quickly locate a migration source Mel Gorman
2019-01-16 13:15 ` Vlastimil Babka
2019-01-16 14:33 ` Mel Gorman
2019-01-16 15:00 ` Vlastimil Babka
2019-01-16 15:43 ` Mel Gorman
2019-01-04 12:49 ` [PATCH 12/25] mm, compaction: Keep migration source private to a single compaction instance Mel Gorman
2019-01-16 15:45 ` Vlastimil Babka
2019-01-16 16:15 ` Mel Gorman
2019-01-17 9:29 ` Vlastimil Babka
2019-01-17 9:40 ` Vlastimil Babka
2019-01-04 12:49 ` [PATCH 13/25] mm, compaction: Use free lists to quickly locate a migration target Mel Gorman
2019-01-17 14:36 ` Vlastimil Babka
2019-01-17 15:51 ` Mel Gorman
2019-01-04 12:50 ` [PATCH 14/25] mm, compaction: Avoid rescanning the same pageblock multiple times Mel Gorman
2019-01-17 15:16 ` Vlastimil Babka
2019-01-17 16:00 ` Mel Gorman
2019-01-04 12:50 ` [PATCH 15/25] mm, compaction: Finish pageblock scanning on contention Mel Gorman
2019-01-17 16:38 ` Vlastimil Babka
2019-01-17 17:11 ` Mel Gorman
2019-01-18 8:57 ` Vlastimil Babka
2019-01-04 12:50 ` [PATCH 16/25] mm, compaction: Check early for huge pages encountered by the migration scanner Mel Gorman
2019-01-17 17:01 ` Vlastimil Babka
2019-01-17 17:35 ` Mel Gorman
2019-01-04 12:50 ` [PATCH 17/25] mm, compaction: Keep cached migration PFNs synced for unusable pageblocks Mel Gorman
2019-01-17 17:17 ` Vlastimil Babka
2019-01-17 17:37 ` Mel Gorman
2019-01-04 12:50 ` [PATCH 18/25] mm, compaction: Rework compact_should_abort as compact_check_resched Mel Gorman
2019-01-17 17:27 ` Vlastimil Babka
2019-01-04 12:50 ` [PATCH 19/25] mm, compaction: Do not consider a need to reschedule as contention Mel Gorman
2019-01-17 17:33 ` Vlastimil Babka
2019-01-17 18:05 ` Mel Gorman
2019-01-04 12:50 ` [PATCH 20/25] mm, compaction: Reduce unnecessary skipping of migration target scanner Mel Gorman
2019-01-17 17:58 ` Vlastimil Babka
2019-01-17 19:39 ` Mel Gorman
2019-01-18 9:09 ` Vlastimil Babka
2019-01-04 12:50 ` [PATCH 21/25] mm, compaction: Round-robin the order while searching the free lists for a target Mel Gorman
2019-01-18 9:17 ` Vlastimil Babka
2019-01-04 12:50 ` [PATCH 22/25] mm, compaction: Sample pageblocks for free pages Mel Gorman
2019-01-18 10:38 ` Vlastimil Babka
2019-01-18 13:44 ` Mel Gorman
2019-01-04 12:50 ` [PATCH 23/25] mm, compaction: Be selective about what pageblocks to clear skip hints Mel Gorman
2019-01-18 12:55 ` Vlastimil Babka
2019-01-18 14:10 ` Mel Gorman [this message]
2019-01-04 12:50 ` [PATCH 24/25] mm, compaction: Capture a page under direct compaction Mel Gorman
2019-01-18 13:40 ` Vlastimil Babka
2019-01-18 14:39 ` Mel Gorman
2019-01-04 12:50 ` [PATCH 25/25] mm, compaction: Do not direct compact remote memory Mel Gorman
2019-01-18 13:51 ` Vlastimil Babka
2019-01-18 14:46 ` Mel Gorman
2019-01-07 23:43 ` [PATCH 00/25] Increase success rates and reduce latency of compaction v2 Andrew Morton
2019-01-08 9:12 ` Mel Gorman
2019-01-09 11:13 ` [PATCH] mm, compaction: Use free lists to quickly locate a migration target -fix Mel Gorman
2019-01-09 19:27 ` Andrew Morton
2019-01-09 21:26 ` Mel Gorman
2019-01-09 11:15 ` [PATCH] mm, compaction: Finish pageblock scanning on contention -fix Mel Gorman
2019-01-09 11:16 ` [PATCH] mm, compaction: Round-robin the order while searching the free lists for a target -fix Mel Gorman
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=20190118141045.GQ27437@techsingularity.net \
--to=mgorman@techsingularity.net \
--cc=aarcange@redhat.com \
--cc=akpm@linux-foundation.org \
--cc=kirill@shutemov.name \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-mm@kvack.org \
--cc=rientjes@google.com \
--cc=vbabka@suse.cz \
--cc=ying.huang@intel.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).