linux-mm.kvack.org archive mirror
 help / color / mirror / Atom feed
From: Anshuman Khandual <anshuman.khandual@arm.com>
To: Nadav Amit <namit@vmware.com>, Barry Song <21cnbao@gmail.com>
Cc: Yicong Yang <yangyicong@huawei.com>,
	Andrew Morton <akpm@linux-foundation.org>,
	Linux MM <linux-mm@kvack.org>,
	"linux-arm-kernel@lists.infradead.org"
	<linux-arm-kernel@lists.infradead.org>,
	"x86@kernel.org" <x86@kernel.org>,
	"catalin.marinas@arm.com" <catalin.marinas@arm.com>,
	Will Deacon <will@kernel.org>,
	"linux-doc@vger.kernel.org" <linux-doc@vger.kernel.org>,
	"corbet@lwn.net" <corbet@lwn.net>,
	"peterz@infradead.org" <peterz@infradead.org>,
	"arnd@arndb.de" <arnd@arndb.de>,
	"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
	"darren@os.amperecomputing.com" <darren@os.amperecomputing.com>,
	"yangyicong@hisilicon.com" <yangyicong@hisilicon.com>,
	"huzhanyuan@oppo.com" <huzhanyuan@oppo.com>,
	"lipeifeng@oppo.com" <lipeifeng@oppo.com>,
	"zhangshiming@oppo.com" <zhangshiming@oppo.com>,
	"guojian@oppo.com" <guojian@oppo.com>,
	"realmz6@gmail.com" <realmz6@gmail.com>,
	"linux-mips@vger.kernel.org" <linux-mips@vger.kernel.org>,
	"openrisc@lists.librecores.org" <openrisc@lists.librecores.org>,
	"linuxppc-dev@lists.ozlabs.org" <linuxppc-dev@lists.ozlabs.org>,
	"linux-riscv@lists.infradead.org"
	<linux-riscv@lists.infradead.org>,
	"linux-s390@vger.kernel.org" <linux-s390@vger.kernel.org>,
	"wangkefeng.wang@huawei.com" <wangkefeng.wang@huawei.com>,
	"xhao@linux.alibaba.com" <xhao@linux.alibaba.com>,
	"prime.zeng@hisilicon.com" <prime.zeng@hisilicon.com>,
	Barry Song <v-songbaohua@oppo.com>, Mel Gorman <mgorman@suse.de>
Subject: Re: [PATCH v3 4/4] arm64: support batched/deferred tlb shootdown during page reclamation
Date: Mon, 19 Sep 2022 08:16:32 +0530	[thread overview]
Message-ID: <7403e6bb-0011-381b-a99e-cbd9d7b1a270@arm.com> (raw)
In-Reply-To: <2AB9EC05-16B4-46F8-B716-53941C1C9A50@vmware.com>



On 9/15/22 20:01, Nadav Amit wrote:
> 
> 
>> On Sep 14, 2022, at 11:42 PM, Barry Song <21cnbao@gmail.com> wrote:
>>
>>>
>>> The very idea behind TLB deferral is the opportunity it (might) provide
>>> to accumulate address ranges and cpu masks so that individual TLB flush
>>> can be replaced with a more cost effective range based TLB flush. Hence
>>> I guess unless address range or cpumask based cost effective TLB flush
>>> is available, deferral does not improve the unmap performance as much.
>>
>>
>> After sending tlbi, if we wait for the completion of tlbi, we have to get Ack
>> from all cpus in the system, tlbi is not scalable. The point here is that we
>> avoid waiting for each individual TLBi. Alternatively, they are batched. If
>> you read the benchmark in the commit log, you can find the great decline
>> in the cost to swap out a page.
> 
> Just a minor correction: arch_tlbbatch_flush() does not collect ranges.
> On x86 it only accumulate CPU mask.

Thanks Nadav for the clarification.


  reply	other threads:[~2022-09-19  2:46 UTC|newest]

Thread overview: 34+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2022-08-22  8:21 [PATCH v3 0/4] mm: arm64: bring up BATCHED_UNMAP_TLB_FLUSH Yicong Yang
2022-08-22  8:21 ` [PATCH v3 1/4] Revert "Documentation/features: mark BATCHED_UNMAP_TLB_FLUSH doesn't apply to ARM64" Yicong Yang
2022-09-09  4:26   ` Anshuman Khandual
2022-09-09  4:40     ` Barry Song
2022-08-22  8:21 ` [PATCH v3 2/4] mm/tlbbatch: Introduce arch_tlbbatch_should_defer() Yicong Yang
2022-08-24  9:40   ` Kefeng Wang
2022-09-09  4:16   ` Anshuman Khandual
2022-08-22  8:21 ` [PATCH v3 3/4] mm: rmap: Extend tlbbatch APIs to fit new platforms Yicong Yang
2022-08-24  9:43   ` Kefeng Wang
2022-09-09  4:51   ` Anshuman Khandual
2022-09-09  5:25     ` Barry Song
2022-08-22  8:21 ` [PATCH v3 4/4] arm64: support batched/deferred tlb shootdown during page reclamation Yicong Yang
2022-08-24  9:46   ` Kefeng Wang
2022-09-09  5:24   ` Anshuman Khandual
2022-09-09  5:35     ` Barry Song
2022-09-09  6:32       ` Yicong Yang
2022-09-15  6:07       ` Anshuman Khandual
2022-09-15  6:42         ` Barry Song
2022-09-15 14:31           ` Nadav Amit
2022-09-19  2:46             ` Anshuman Khandual [this message]
2022-09-19  4:24           ` Anshuman Khandual
2022-09-19  4:53             ` Barry Song
2022-09-19  5:08               ` Barry Song
2022-09-20  3:00   ` Anshuman Khandual
2022-09-20  3:39     ` Barry Song
2022-09-20  8:45       ` Anshuman Khandual
2022-09-21  1:50         ` Barry Song
2022-09-21  1:51           ` Barry Song
2022-09-21  3:33             ` Anshuman Khandual
2022-09-21  6:53   ` Anshuman Khandual
2022-09-21  7:15     ` Barry Song
2022-09-21  7:17     ` Nadav Amit
2022-09-22  3:15       ` Anshuman Khandual
2022-09-06  8:53 ` [PATCH v3 0/4] mm: arm64: bring up BATCHED_UNMAP_TLB_FLUSH Yicong Yang

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=7403e6bb-0011-381b-a99e-cbd9d7b1a270@arm.com \
    --to=anshuman.khandual@arm.com \
    --cc=21cnbao@gmail.com \
    --cc=akpm@linux-foundation.org \
    --cc=arnd@arndb.de \
    --cc=catalin.marinas@arm.com \
    --cc=corbet@lwn.net \
    --cc=darren@os.amperecomputing.com \
    --cc=guojian@oppo.com \
    --cc=huzhanyuan@oppo.com \
    --cc=linux-arm-kernel@lists.infradead.org \
    --cc=linux-doc@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-mips@vger.kernel.org \
    --cc=linux-mm@kvack.org \
    --cc=linux-riscv@lists.infradead.org \
    --cc=linux-s390@vger.kernel.org \
    --cc=linuxppc-dev@lists.ozlabs.org \
    --cc=lipeifeng@oppo.com \
    --cc=mgorman@suse.de \
    --cc=namit@vmware.com \
    --cc=openrisc@lists.librecores.org \
    --cc=peterz@infradead.org \
    --cc=prime.zeng@hisilicon.com \
    --cc=realmz6@gmail.com \
    --cc=v-songbaohua@oppo.com \
    --cc=wangkefeng.wang@huawei.com \
    --cc=will@kernel.org \
    --cc=x86@kernel.org \
    --cc=xhao@linux.alibaba.com \
    --cc=yangyicong@hisilicon.com \
    --cc=yangyicong@huawei.com \
    --cc=zhangshiming@oppo.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