From: Andrea Arcangeli <aarcange@redhat.com>
To: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will@kernel.org>, Jon Masters <jcm@jonmasters.org>,
Rafael Aquini <aquini@redhat.com>,
Mark Salter <msalter@redhat.com>,
linux-kernel@vger.kernel.org, linux-mm@kvack.org,
linux-arm-kernel@lists.infradead.org
Subject: Re: [PATCH 2/2] arm64: tlb: skip tlbi broadcast for single threaded TLB flushes
Date: Wed, 12 Feb 2020 07:57:57 -0500 [thread overview]
Message-ID: <20200212125757.GD3699@redhat.com> (raw)
In-Reply-To: <20200211140025.GB153117@arrakis.emea.arm.com>
Hello,
On Tue, Feb 11, 2020 at 02:00:25PM +0000, Catalin Marinas wrote:
> I think there is another race here. IIUC, the assumption you make is
> that when mm_users <= 1 && mm_count == 1, the only active user of this
> pgd/ASID is on the CPU doing the TLBI. This is not the case for
> try_to_unmap() where the above condition may be true but the active
> thread on a different CPU won't notice the local TLBI.
The "current->mm == mm" check is what shall prevent the above.
Thanks,
Andrea
next prev parent reply other threads:[~2020-02-12 12:58 UTC|newest]
Thread overview: 13+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-02-03 20:17 [RFC] [PATCH 0/2] arm64: tlb: skip tlbi broadcast for single threaded TLB flushes Andrea Arcangeli
2020-02-03 20:17 ` [PATCH 1/2] mm: use_mm: fix for arches checking mm_users to optimize " Andrea Arcangeli
2020-02-18 11:31 ` Michal Hocko
2020-02-18 18:56 ` Andrea Arcangeli
2020-02-19 11:58 ` Michal Hocko
2020-02-19 20:04 ` Andrea Arcangeli
2020-02-03 20:17 ` [PATCH 2/2] arm64: tlb: skip tlbi broadcast for single threaded " Andrea Arcangeli
2020-02-10 17:51 ` Catalin Marinas
2020-02-10 20:14 ` Andrea Arcangeli
2020-02-11 14:00 ` Catalin Marinas
2020-02-12 12:57 ` Andrea Arcangeli [this message]
2020-02-12 14:13 ` qi.fuli
2020-02-12 15:26 ` Catalin Marinas
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=20200212125757.GD3699@redhat.com \
--to=aarcange@redhat.com \
--cc=aquini@redhat.com \
--cc=catalin.marinas@arm.com \
--cc=jcm@jonmasters.org \
--cc=linux-arm-kernel@lists.infradead.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-mm@kvack.org \
--cc=msalter@redhat.com \
--cc=will@kernel.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
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).