From: Andi Kleen <andi@firstfloor.org>
To: Laurent Dufour <ldufour@linux.vnet.ibm.com>
Cc: "Kirill A . Shutemov" <kirill@shutemov.name>,
Peter Zijlstra <peterz@infradead.org>,
Linux MM <linux-mm@kvack.org>, Michal Hocko <mhocko@suse.cz>
Subject: Re: [RFC PATCH v2 0/7] Speculative page faults
Date: Fri, 18 Nov 2016 06:08:24 -0800 [thread overview]
Message-ID: <871sy8284n.fsf@tassilo.jf.intel.com> (raw)
In-Reply-To: <cover.1479465699.git.ldufour@linux.vnet.ibm.com> (Laurent Dufour's message of "Fri, 18 Nov 2016 12:08:44 +0100")
Laurent Dufour <ldufour@linux.vnet.ibm.com> writes:
> This is a port on kernel 4.8 of the work done by Peter Zijlstra to
> handle page fault without holding the mm semaphore.
One of the big problems with patches like this today is that it is
unclear what mmap_sem actually protects. It's a big lock covering lots
of code. Parts in the core VM, but also do VM callbacks in file systems
and drivers rely on it too?
IMHO the first step is a comprehensive audit and then writing clear
documentation on what it is supposed to protect. Then based on that such
changes can be properly evaluated.
-Andi
--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to majordomo@kvack.org. For more info on Linux MM,
see: http://www.linux-mm.org/ .
Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a>
next prev parent reply other threads:[~2016-11-18 14:08 UTC|newest]
Thread overview: 21+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-10-17 12:33 mmap_sem bottleneck Laurent Dufour
2016-10-17 12:51 ` Peter Zijlstra
2016-10-18 14:50 ` Laurent Dufour
2016-10-18 15:01 ` Kirill A. Shutemov
2016-10-18 15:02 ` Peter Zijlstra
2016-11-18 11:08 ` [RFC PATCH v2 0/7] Speculative page faults Laurent Dufour
2016-11-18 11:08 ` [RFC PATCH v2 1/7] mm: Dont assume page-table invariance during faults Laurent Dufour
2016-11-18 11:08 ` [RFC PATCH v2 2/7] mm: Prepare for FAULT_FLAG_SPECULATIVE Laurent Dufour
2016-11-18 11:08 ` [RFC PATCH v2 3/7] mm: Introduce pte_spinlock Laurent Dufour
2016-11-18 11:08 ` [RFC PATCH v2 4/7] mm: VMA sequence count Laurent Dufour
2016-11-18 11:08 ` [RFC PATCH v2 5/7] SRCU free VMAs Laurent Dufour
2016-11-18 11:08 ` [RFC PATCH v2 6/7] mm: Provide speculative fault infrastructure Laurent Dufour
2016-11-18 11:08 ` [RFC PATCH v2 7/7] mm,x86: Add speculative pagefault handling Laurent Dufour
2016-11-18 14:08 ` Andi Kleen [this message]
2016-12-01 8:34 ` [RFC PATCH v2 0/7] Speculative page faults Laurent Dufour
2016-12-01 12:50 ` Balbir Singh
2016-12-01 13:26 ` Laurent Dufour
2016-12-02 14:10 ` Michal Hocko
2016-10-17 12:57 ` mmap_sem bottleneck Michal Hocko
2016-10-20 7:23 ` Laurent Dufour
2016-10-20 10:55 ` Michal Hocko
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=871sy8284n.fsf@tassilo.jf.intel.com \
--to=andi@firstfloor.org \
--cc=kirill@shutemov.name \
--cc=ldufour@linux.vnet.ibm.com \
--cc=linux-mm@kvack.org \
--cc=mhocko@suse.cz \
--cc=peterz@infradead.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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.