Linux-Next Archive on lore.kernel.org
 help / color / Atom feed
From: Peter Zijlstra <peterz@infradead.org>
To: Ingo Molnar <mingo@kernel.org>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>,
	Andrew Morton <akpm@linux-foundation.org>,
	Thomas Gleixner <tglx@linutronix.de>, Ingo Molnar <mingo@elte.hu>,
	"H. Peter Anvin" <hpa@zytor.com>,
	Linux-Next Mailing List <linux-next@vger.kernel.org>,
	Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
	Nadav Amit <namit@vmware.com>,
	Linus <torvalds@linux-foundation.org>
Subject: Re: linux-next: manual merge of the akpm-current tree with the tip tree
Date: Fri, 11 Aug 2017 14:17:42 +0200
Message-ID: <20170811121742.sv3tfysnydsqpg2a@hirez.programming.kicks-ass.net> (raw)
In-Reply-To: <20170811115607.p2vgqcp7w3wurhvw@gmail.com>

On Fri, Aug 11, 2017 at 01:56:07PM +0200, Ingo Molnar wrote:
> I've done a minimal conflict resolution merge locally. Peter, could you please 
> double check my resolution, in:
> 
>   040cca3ab2f6: Merge branch 'linus' into locking/core, to resolve conflicts

That merge is a bit wonky, but not terminally broken afaict.

It now does two TLB flushes, the below cleans that up.

---
 mm/huge_memory.c | 22 +++++-----------------
 1 file changed, 5 insertions(+), 17 deletions(-)

diff --git a/mm/huge_memory.c b/mm/huge_memory.c
index ce883459e246..08f6c1993832 100644
--- a/mm/huge_memory.c
+++ b/mm/huge_memory.c
@@ -1410,7 +1410,6 @@ int do_huge_pmd_numa_page(struct vm_fault *vmf, pmd_t pmd)
 	unsigned long haddr = vmf->address & HPAGE_PMD_MASK;
 	int page_nid = -1, this_nid = numa_node_id();
 	int target_nid, last_cpupid = -1;
-	bool need_flush = false;
 	bool page_locked;
 	bool migrated = false;
 	bool was_writable;
@@ -1497,22 +1496,18 @@ int do_huge_pmd_numa_page(struct vm_fault *vmf, pmd_t pmd)
 	}
 
 	/*
-	 * The page_table_lock above provides a memory barrier
-	 * with change_protection_range.
-	 */
-	if (mm_tlb_flush_pending(vma->vm_mm))
-		flush_tlb_range(vma, haddr, haddr + HPAGE_PMD_SIZE);
-
-	/*
 	 * Since we took the NUMA fault, we must have observed the !accessible
 	 * bit. Make sure all other CPUs agree with that, to avoid them
 	 * modifying the page we're about to migrate.
 	 *
 	 * Must be done under PTL such that we'll observe the relevant
-	 * set_tlb_flush_pending().
+	 * inc_tlb_flush_pending().
+	 *
+	 * We are not sure a pending tlb flush here is for a huge page
+	 * mapping or not. Hence use the tlb range variant
 	 */
 	if (mm_tlb_flush_pending(vma->vm_mm))
-		need_flush = true;
+		flush_tlb_range(vma, haddr, haddr + HPAGE_PMD_SIZE);
 
 	/*
 	 * Migrate the THP to the requested node, returns with page unlocked
@@ -1520,13 +1515,6 @@ int do_huge_pmd_numa_page(struct vm_fault *vmf, pmd_t pmd)
 	 */
 	spin_unlock(vmf->ptl);
 
-	/*
-	 * We are not sure a pending tlb flush here is for a huge page
-	 * mapping or not. Hence use the tlb range variant
-	 */
-	if (need_flush)
-		flush_tlb_range(vma, haddr, haddr + HPAGE_PMD_SIZE);
-
 	migrated = migrate_misplaced_transhuge_page(vma->vm_mm, vma,
 				vmf->pmd, pmd, vmf->address, page, target_nid);
 	if (migrated) {

  reply index

Thread overview: 87+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2017-08-11  7:53 Stephen Rothwell
2017-08-11  9:34 ` Peter Zijlstra
2017-08-11 10:48   ` Peter Zijlstra
2017-08-11 11:45   ` Stephen Rothwell
2017-08-11 11:56     ` Ingo Molnar
2017-08-11 12:17       ` Peter Zijlstra [this message]
2017-08-11 12:44         ` Ingo Molnar
2017-08-11 13:49           ` Stephen Rothwell
2017-08-11 14:04       ` Peter Zijlstra
2017-08-13  6:06         ` Nadav Amit
2017-08-13 12:50           ` Peter Zijlstra
2017-08-14  3:16             ` Minchan Kim
2017-08-14  5:07               ` Nadav Amit
2017-08-14  5:23                 ` Minchan Kim
2017-08-14  8:38                 ` Minchan Kim
2017-08-14 19:57                   ` Peter Zijlstra
2017-08-16  4:14                     ` Minchan Kim
2017-08-14 19:38                 ` Peter Zijlstra
2017-08-15  7:51                   ` Nadav Amit
2017-08-14  3:09         ` Minchan Kim
2017-08-14 18:54           ` Peter Zijlstra
  -- strict thread matches above, loose matches on Subject: below --
2019-10-31  5:43 Stephen Rothwell
2019-06-24 10:24 Stephen Rothwell
2019-05-01 11:10 Stephen Rothwell
2019-01-31  4:31 Stephen Rothwell
2018-08-20  4:32 Stephen Rothwell
2018-08-20 19:52 ` Andrew Morton
2018-03-23  5:59 Stephen Rothwell
2017-12-18  5:04 Stephen Rothwell
2017-11-10  4:33 Stephen Rothwell
2017-11-02  7:19 Stephen Rothwell
2017-08-22  6:57 Stephen Rothwell
2017-08-23  6:39 ` Vlastimil Babka
2017-04-12  6:46 Stephen Rothwell
2017-04-12 20:53 ` Vlastimil Babka
2017-04-20  2:17   ` NeilBrown
2017-03-24  5:25 Stephen Rothwell
2017-02-17  4:40 Stephen Rothwell
2016-11-14  6:08 Stephen Rothwell
2016-07-29  4:14 Stephen Rothwell
2016-06-15  5:23 Stephen Rothwell
2016-06-18 19:39 ` Manfred Spraul
2016-04-29  6:12 Stephen Rothwell
2016-04-29  6:26 ` Ingo Molnar
2016-03-02  5:40 Stephen Rothwell
2016-02-26  5:07 Stephen Rothwell
2016-02-26 21:35 ` Andrew Morton
2016-02-19  4:09 Stephen Rothwell
2016-02-19 15:26 ` Ard Biesheuvel
2015-12-07  8:06 Stephen Rothwell
2015-10-02  4:21 Stephen Rothwell
2015-07-28  6:00 Stephen Rothwell
2015-07-29 17:12 ` Andrea Arcangeli
2015-07-29 17:47   ` Andy Lutomirski
2015-07-29 18:46     ` Thomas Gleixner
2015-07-30 15:38       ` Andrea Arcangeli
2015-07-29 23:06   ` Stephen Rothwell
2015-07-29 23:07     ` Thomas Gleixner
2015-09-07 23:35   ` Stephen Rothwell
2015-09-08 18:11     ` Linus Torvalds
2015-09-08 22:56       ` Stephen Rothwell
2015-09-08 23:03         ` Linus Torvalds
2015-09-08 23:21           ` Andrew Morton
2015-09-16  6:58             ` Geert Uytterhoeven
2015-06-04 12:07 Stephen Rothwell
2015-04-08  8:28 Stephen Rothwell
2015-04-08  8:25 Stephen Rothwell
2014-03-17  9:31 Stephen Rothwell
2014-03-17  9:36 ` Peter Zijlstra
2014-03-19 23:27   ` Andrew Morton
2014-01-14  4:53 Stephen Rothwell
2014-01-14  5:04 ` Davidlohr Bueso
2014-01-14 12:51 ` Peter Zijlstra
2014-01-14 13:17   ` Geert Uytterhoeven
2014-01-14 13:33     ` Peter Zijlstra
2014-01-14 16:19     ` H. Peter Anvin
2014-01-14 15:15   ` H. Peter Anvin
2014-01-14 15:20     ` Geert Uytterhoeven
2014-01-14 15:41       ` Peter Zijlstra
2014-01-14 15:48         ` H. Peter Anvin
2014-01-07  6:00 Stephen Rothwell
2014-01-07  6:34 ` Tang Chen
2013-11-08  7:48 Stephen Rothwell
2013-11-08 18:58 ` Josh Triplett
2013-11-08 23:20   ` Stephen Rothwell
2013-11-09  0:19     ` Josh Triplett
2013-10-30  6:40 Stephen Rothwell

Reply instructions:

You may reply publically 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=20170811121742.sv3tfysnydsqpg2a@hirez.programming.kicks-ass.net \
    --to=peterz@infradead.org \
    --cc=akpm@linux-foundation.org \
    --cc=hpa@zytor.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-next@vger.kernel.org \
    --cc=mingo@elte.hu \
    --cc=mingo@kernel.org \
    --cc=namit@vmware.com \
    --cc=sfr@canb.auug.org.au \
    --cc=tglx@linutronix.de \
    --cc=torvalds@linux-foundation.org \
    /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

Linux-Next Archive on lore.kernel.org

Archives are clonable:
	git clone --mirror https://lore.kernel.org/linux-next/0 linux-next/git/0.git

	# If you have public-inbox 1.1+ installed, you may
	# initialize and index your mirror using the following commands:
	public-inbox-init -V2 linux-next linux-next/ https://lore.kernel.org/linux-next \
		linux-next@vger.kernel.org
	public-inbox-index linux-next

Example config snippet for mirrors

Newsgroup available over NNTP:
	nntp://nntp.lore.kernel.org/org.kernel.vger.linux-next


AGPL code for this site: git clone https://public-inbox.org/public-inbox.git