linux-kernel - [PATCH 0/2] hugepage: optimize page fault path locking

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [thread-next>] [day] [month] [year] [list]

Date:	Fri, 26 Jul 2013 07:27:23 -0700
From:	Davidlohr Bueso <davidlohr.bueso@...com>
To:	Andrew Morton <akpm@...ux-foundation.org>
Cc:	Rik van Riel <riel@...hat.com>,
	Michel Lespinasse <walken@...gle.com>,
	Mel Gorman <mgorman@...e.de>, Michal Hocko <mhocko@...e.cz>,
	"AneeshKumarK.V" <aneesh.kumar@...ux.vnet.ibm.com>,
	KAMEZAWA Hiroyuki <kamezawa.hiroyu@...fujitsu.com>,
	Hillf Danton <dhillf@...il.com>,
	Hugh Dickins <hughd@...gle.com>,
	Joonsoo Kim <iamjoonsoo.kim@....com>,
	David Gibson <david@...son.dropbear.id.au>,
	Eric B Munson <emunson@...bm.net>,
	Anton Blanchard <anton@...ba.org>,
	Konstantin Khlebnikov <khlebnikov@...nvz.org>,
	linux-mm@...ck.org, linux-kernel@...r.kernel.org,
	Davidlohr Bueso <davidlohr.bueso@...com>
Subject: [PATCH 0/2] hugepage: optimize page fault path locking

This patchset attempts to reduce the amount of contention we impose
on the hugetlb_instantiation_mutex by replacing the global mutex with
a table of mutexes, selected based on a hash. The original discussion can 
be found here: http://lkml.org/lkml/2013/7/12/428

Patch 1: Allows the file region tracking list to be serialized by its own rwsem.
This is necessary because the next patch allows concurrent hugepage fault paths,
getting rid of the hugetlb_instantiation_mutex - which protects chains of struct 
file_regionin inode->i_mapping->private_list (VM_MAYSHARE) or vma_resv_map(vma)->regions 
(!VM_MAYSHARE).

Patch 2: From David Gibson, for some reason never made it into the kernel. 
Further cleanups and enhancements from Anton Blanchard and myself.
Details of how the hash key is selected is in the patch.

Davidlohr Bueso (2):
  hugepage: protect file regions with rwsem
  hugepage: allow parallelization of the hugepage fault path

 mm/hugetlb.c | 134 ++++++++++++++++++++++++++++++++++++++++++++++-------------
 1 file changed, 106 insertions(+), 28 deletions(-)

-- 
1.7.11.7

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/