From: David Hildenbrand <david@redhat.com>
To: Matthew Wilcox <willy@infradead.org>,
Dave Hansen <dave.hansen@intel.com>
Cc: Byungchul Park <byungchul@sk.com>,
Byungchul Park <lkml.byungchul.park@gmail.com>,
linux-kernel@vger.kernel.org, linux-mm@kvack.org,
kernel_team@skhynix.com, akpm@linux-foundation.org,
ying.huang@intel.com, vernhao@tencent.com,
mgorman@techsingularity.net, hughd@google.com,
peterz@infradead.org, luto@kernel.org, tglx@linutronix.de,
mingo@redhat.com, bp@alien8.de, dave.hansen@linux.intel.com,
rjgolo@gmail.com
Subject: Re: [PATCH v11 09/12] mm: implement LUF(Lazy Unmap Flush) defering tlb flush when folios get unmapped
Date: Mon, 3 Jun 2024 20:00:52 +0200 [thread overview]
Message-ID: <24daabde-300e-4a28-9a1c-9e406b087195@redhat.com> (raw)
In-Reply-To: <Zl320dWODSYw-PgV@casper.infradead.org>
On 03.06.24 19:01, Matthew Wilcox wrote:
> On Mon, Jun 03, 2024 at 09:37:46AM -0700, Dave Hansen wrote:
>> Yeah, we'd need some equivalent of a PTE marker, but for the page cache.
>> Presumably some xa_value() that means a reader has to go do a
>> luf_flush() before going any farther.
>
> I can allocate one for that. We've got something like 1000 currently
> unused values which can't be mistaken for anything else.
I'm curious when to set that, though.
While migrating/reclaiming, when unmapping the folio from the page
tables, the folio is still valid in the page cache. So at the point in
time of unmapping from one process, we cannot simply replace the folio
in the page cache by some other value -- I think.
Maybe it's all easier than I think.
--
Cheers,
David / dhildenb
next prev parent reply other threads:[~2024-06-03 18:01 UTC|newest]
Thread overview: 36+ messages / expand[flat|nested] mbox.gz Atom feed top
2024-05-31 9:19 [PATCH v11 00/12] LUF(Lazy Unmap Flush) reducing tlb numbers over 90% Byungchul Park
2024-05-31 9:19 ` [PATCH v11 01/12] x86/tlb: add APIs manipulating tlb batch's arch data Byungchul Park
2024-05-31 9:19 ` [PATCH v11 02/12] arm64: tlbflush: " Byungchul Park
2024-05-31 9:19 ` [PATCH v11 03/12] riscv, tlb: " Byungchul Park
2024-05-31 9:19 ` [PATCH v11 04/12] x86/tlb, riscv/tlb, mm/rmap: separate arch_tlbbatch_clear() out of arch_tlbbatch_flush() Byungchul Park
2024-05-31 9:19 ` [PATCH v11 05/12] mm: buddy: make room for a new variable, ugen, in struct page Byungchul Park
2024-05-31 9:19 ` [PATCH v11 06/12] mm: add folio_put_ugen() to deliver unmap generation number to pcp or buddy Byungchul Park
2024-05-31 9:19 ` [PATCH v11 07/12] mm: add a parameter, unmap generation number, to free_unref_folios() Byungchul Park
2024-05-31 9:19 ` [PATCH v11 08/12] mm/rmap: recognize read-only tlb entries during batched tlb flush Byungchul Park
2024-05-31 9:19 ` [PATCH v11 09/12] mm: implement LUF(Lazy Unmap Flush) defering tlb flush when folios get unmapped Byungchul Park
2024-05-31 16:12 ` Dave Hansen
2024-05-31 18:04 ` Byungchul Park
2024-05-31 21:46 ` Dave Hansen
2024-05-31 22:09 ` Matthew Wilcox
2024-06-01 2:20 ` Byungchul Park
2024-06-01 7:22 ` David Hildenbrand
2024-06-03 9:35 ` Byungchul Park
2024-06-03 13:23 ` Dave Hansen
2024-06-03 16:05 ` David Hildenbrand
2024-06-03 16:37 ` Dave Hansen
2024-06-03 17:01 ` Matthew Wilcox
2024-06-03 18:00 ` David Hildenbrand [this message]
2024-06-04 8:16 ` Huang, Ying
2024-06-04 0:34 ` Byungchul Park
2024-06-10 13:23 ` Michal Hocko
2024-06-11 0:55 ` Byungchul Park
2024-06-11 11:55 ` Michal Hocko
2024-06-14 2:45 ` Byungchul Park
2024-06-04 1:53 ` Byungchul Park
2024-06-04 4:43 ` Byungchul Park
2024-06-06 8:33 ` David Hildenbrand
2024-06-14 1:57 ` Byungchul Park
2024-06-11 9:12 ` Byungchul Park
2024-05-31 9:19 ` [PATCH v11 10/12] mm: separate move/undo parts from migrate_pages_batch() Byungchul Park
2024-05-31 9:20 ` [PATCH v11 11/12] mm, migrate: apply luf mechanism to unmapping during migration Byungchul Park
2024-05-31 9:20 ` [PATCH v11 12/12] mm, vmscan: apply luf mechanism to unmapping during folio reclaim Byungchul Park
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