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From: Vlastimil Babka <vbabka@suse.cz>
To: linux-mm@kvack.org
Cc: Christoph Lameter <cl@linux.com>,
	Pekka Enberg <penberg@kernel.org>,
	David Rientjes <rientjes@google.com>,
	Joonsoo Kim <iamjoonsoo.kim@lge.com>,
	Ming Lei <ming.lei@redhat.com>,
	Dave Chinner <david@fromorbit.com>,
	Matthew Wilcox <willy@infradead.org>,
	"Darrick J . Wong" <darrick.wong@oracle.com>,
	Christoph Hellwig <hch@lst.de>, Michal Hocko <mhocko@kernel.org>,
	linux-kernel@vger.kernel.org, linux-xfs@vger.kernel.org,
	linux-fsdevel@vger.kernel.org, linux-block@vger.kernel.org,
	Vlastimil Babka <vbabka@suse.cz>
Subject: [RFC 0/2] guarantee natural alignment for kmalloc()
Date: Tue, 19 Mar 2019 22:11:06 +0100	[thread overview]
Message-ID: <20190319211108.15495-1-vbabka@suse.cz> (raw)

The recent thread [1] inspired me to look into guaranteeing alignment for
kmalloc() for power-of-two sizes. Turns out it's not difficult and in most
configuration nothing really changes as it happens implicitly. More details in
the first patch. If we agree we want to do this, I will see where to update
documentation and perhaps if there are any workarounds in the tree that can be
converted to plain kmalloc() afterwards.

The second patch is quick and dirty selftest for the alignment. Suggestions
welcome whether and how to include this kind of selftest that has to be
in-kernel.

[1] https://lore.kernel.org/linux-fsdevel/20190225040904.5557-1-ming.lei@redhat.com/T/#u

Vlastimil Babka (2):
  mm, sl[aou]b: guarantee natural alignment for kmalloc(power-of-two)
  mm, sl[aou]b: test whether kmalloc() alignment works as expected

 mm/slab_common.c | 30 +++++++++++++++++++++++++++++-
 mm/slob.c        | 42 +++++++++++++++++++++++++++++++-----------
 2 files changed, 60 insertions(+), 12 deletions(-)

-- 
2.21.0


             reply	other threads:[~2019-03-19 21:11 UTC|newest]

Thread overview: 18+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-03-19 21:11 Vlastimil Babka [this message]
2019-03-19 21:11 ` [RFC 1/2] mm, sl[aou]b: guarantee natural alignment for kmalloc(power-of-two) Vlastimil Babka
2019-03-19 21:11 ` [RFC 2/2] mm, sl[aou]b: test whether kmalloc() alignment works as expected Vlastimil Babka
2019-03-20  0:44   ` Christopher Lameter
2019-03-20  0:43 ` [RFC 0/2] guarantee natural alignment for kmalloc() Christopher Lameter
2019-03-20  0:53   ` David Rientjes
2019-03-20  8:48   ` Vlastimil Babka
2019-03-20 18:20     ` Christopher Lameter
2019-03-21  7:42       ` Vlastimil Babka
2019-03-22 17:52         ` Christopher Lameter
2019-04-05 17:11           ` Vlastimil Babka
2019-04-07  8:00             ` Christoph Hellwig
2019-04-09  8:07               ` Vlastimil Babka
2019-04-09  9:20                 ` Michal Hocko
2019-03-20 18:53     ` Matthew Wilcox
2019-03-20 21:48       ` Vlastimil Babka
2019-03-21  2:23         ` Matthew Wilcox
2019-03-21  7:02           ` Vlastimil Babka

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