Andrew Morton wrote:
> On Wed, 12 Nov 2014 13:08:55 +0900 Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp> wrote:
>
> > Andrew Morton wrote:
> > > Poor ttm guys - this is a bit of a trap we set for them.
> >
> > Commit a91576d791 ("drm/ttm: Pass GFP flags in order to avoid deadlock.")
> > changed to use sc->gfp_mask rather than GFP_KERNEL.
> >
> > - pages_to_free = kmalloc(npages_to_free * sizeof(struct page *),
> > - GFP_KERNEL);
> > + pages_to_free = kmalloc(npages_to_free * sizeof(struct page *), gfp);
> >
> > But this bug is caused by sc->gfp_mask containing some flags which are not
> > in GFP_KERNEL, right? Then, I think
> >
> > - pages_to_free = kmalloc(npages_to_free * sizeof(struct page *), gfp);
> > + pages_to_free = kmalloc(npages_to_free * sizeof(struct page *), gfp & GFP_KERNEL);
> >
> > would hide this bug.
> >
> > But I think we should use GFP_ATOMIC (or drop __GFP_WAIT flag)
>
> Well no - ttm_page_pool_free() should stop calling kmalloc altogether.
> Just do
>
> struct page *pages_to_free[16];
>
> and rework the code to free 16 pages at a time. Easy.
Well, ttm code wants to process 512 pages at a time for performance.
Memory footprint increased by 512 * sizeof(struct page *) buffer is
only 4096 bytes. What about using static buffer like below?
----------
>From d3cb5393c9c8099d6b37e769f78c31af1541fe8c Mon Sep 17 00:00:00 2001
From: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Date: Thu, 13 Nov 2014 22:21:54 +0900
Subject: [PATCH] drm/ttm: Avoid memory allocation from shrinker functions.
Commit a91576d791 ("drm/ttm: Pass GFP flags in order to avoid
deadlock.") caused BUG_ON() due to sc->gfp_mask containing flags
which are not in GFP_KERNEL.
https://bugzilla.kernel.org/show_bug.cgi?id=87891
Changing from sc->gfp_mask to (sc->gfp_mask & GFP_KERNEL) would
avoid the BUG_ON(), but avoiding memory allocation from shrinker
function is better and reliable fix.
Shrinker function is already serialized by global lock, and
clean up function is called after shrinker function is unregistered.
Thus, we can use static buffer when called from shrinker function
and clean up function.
Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Cc: stable <stable@kernel.org> [2.6.35+]
Signed-off-by: Dave Airlie <airlied@redhat.com>
Commit 7dc19d5a "drivers: convert shrinkers to new count/scan API" added
deadlock warnings that ttm_page_pool_free() and ttm_dma_page_pool_free()
are currently doing GFP_KERNEL allocation.
But these functions did not get updated to receive gfp_t argument.
This patch explicitly passes sc->gfp_mask or GFP_KERNEL to these functions,
and removes the deadlock warning.
Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Cc: stable <stable@kernel.org> [2.6.35+]
Signed-off-by: Dave Airlie <airlied@redhat.com>
While ttm_dma_pool_shrink_scan() tries to take mutex before doing GFP_KERNEL
allocation, ttm_pool_shrink_scan() does not do it. This can result in stack
overflow if kmalloc() in ttm_page_pool_free() triggered recursion due to
memory pressure.
shrink_slab()
=> ttm_pool_shrink_scan()
=> ttm_page_pool_free()
=> kmalloc(GFP_KERNEL)
=> shrink_slab()
=> ttm_pool_shrink_scan()
=> ttm_page_pool_free()
=> kmalloc(GFP_KERNEL)
Change ttm_pool_shrink_scan() to do like ttm_dma_pool_shrink_scan() does.
Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Cc: stable <stable@kernel.org> [2.6.35+]
Signed-off-by: Dave Airlie <airlied@redhat.com>
Convert the driver shrinkers to the new API. Most changes are compile
tested only because I either don't have the hardware or it's staging
stuff.
FWIW, the md and android code is pretty good, but the rest of it makes me
want to claw my eyes out. The amount of broken code I just encountered is
mind boggling. I've added comments explaining what is broken, but I fear
that some of the code would be best dealt with by being dragged behind the
bike shed, burying in mud up to it's neck and then run over repeatedly
with a blunt lawn mower.
Special mention goes to the zcache/zcache2 drivers. They can't co-exist
in the build at the same time, they are under different menu options in
menuconfig, they only show up when you've got the right set of mm
subsystem options configured and so even compile testing is an exercise in
pulling teeth. And that doesn't even take into account the horrible,
broken code...
[glommer@openvz.org: fixes for i915, android lowmem, zcache, bcache]
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Glauber Costa <glommer@openvz.org>
Acked-by: Mel Gorman <mgorman@suse.de>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Kent Overstreet <koverstreet@google.com>
Cc: John Stultz <john.stultz@linaro.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Jerome Glisse <jglisse@redhat.com>
Cc: Thomas Hellstrom <thellstrom@vmware.com>
Cc: "Theodore Ts'o" <tytso@mit.edu>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Cc: Arve Hjønnevåg <arve@android.com>
Cc: Carlos Maiolino <cmaiolino@redhat.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Chuck Lever <chuck.lever@oracle.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: David Rientjes <rientjes@google.com>
Cc: Gleb Natapov <gleb@redhat.com>
Cc: Greg Thelen <gthelen@google.com>
Cc: J. Bruce Fields <bfields@redhat.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Jerome Glisse <jglisse@redhat.com>
Cc: John Stultz <john.stultz@linaro.org>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Kent Overstreet <koverstreet@google.com>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Steven Whitehouse <swhiteho@redhat.com>
Cc: Thomas Hellstrom <thellstrom@vmware.com>
Cc: Trond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
The TTM page can be allocated from high memory. In such case it is
wrong to use the page_address(page) as the virtual address for the high memory
page.
bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=50241
Signed-off-by: Zhao Yakui <yakui.zhao@intel.com>
Cc: stable@vger.kernel.org
Reviewed-by: Thomas Hellstrom <thellstrom@vmware.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Convert #include "..." to #include <path/...> in drivers/gpu/.
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Dave Airlie <airlied@redhat.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Acked-by: Dave Jones <davej@redhat.com>
Use the more current logging style.
Add pr_fmt and remove the TTM_PFX uses.
Coalesce formats and align arguments.
Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Move dma data to a superset ttm_dma_tt structure which herit
from ttm_tt. This allow driver that don't use dma functionalities
to not have to waste memory for it.
V2 Rebase on top of no memory account changes (where/when is my
delorean when i need it ?)
V3 Make sure page list is initialized empty
V4 typo/syntax fixes
Signed-off-by: Jerome Glisse <jglisse@redhat.com>
Reviewed-by: Thomas Hellstrom <thellstrom@vmware.com>
Move the page allocation and freeing to driver callback and
provide ttm code helper function for those.
Most intrusive change, is the fact that we now only fully
populate an object this simplify some of code designed around
the page fault design.
V2 Rebase on top of memory accounting overhaul
V3 New rebase on top of more memory accouting changes
V4 Rebase on top of no memory account changes (where/when is my
delorean when i need it ?)
Signed-off-by: Jerome Glisse <jglisse@redhat.com>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Reviewed-by: Thomas Hellstrom <thellstrom@vmware.com>
Use the ttm_tt pages array for pages allocations, move the list
unwinding into the page allocation functions.
Signed-off-by: Jerome Glisse <jglisse@redhat.com>
This allows us to move duplicated code in <asm/atomic.h>
(atomic_inc_not_zero() for now) to <linux/atomic.h>
Signed-off-by: Arun Sharma <asharma@fb.com>
Reviewed-by: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: David Miller <davem@davemloft.net>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Acked-by: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
. and some comments to make it easier to understand.
Ackedby: Randy Dunlap <randy.dunlap@oracle.com>
[v2: Added some more updates from Randy Dunlap]
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Change each shrinker's API by consolidating the existing parameters into
shrink_control struct. This will simplify any further features added w/o
touching each file of shrinker.
[akpm@linux-foundation.org: fix build]
[akpm@linux-foundation.org: fix warning]
[kosaki.motohiro@jp.fujitsu.com: fix up new shrinker API]
[akpm@linux-foundation.org: fix xfs warning]
[akpm@linux-foundation.org: update gfs2]
Signed-off-by: Ying Han <yinghan@google.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Minchan Kim <minchan.kim@gmail.com>
Acked-by: Pavel Emelyanov <xemul@openvz.org>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Mel Gorman <mel@csn.ul.ie>
Acked-by: Rik van Riel <riel@redhat.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Hugh Dickins <hughd@google.com>
Cc: Dave Hansen <dave@linux.vnet.ibm.com>
Cc: Steven Whitehouse <swhiteho@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This reverts commit 69a07f0b11.
We've tracked a number of problems back to this, and Thomas
thinks we should redesign this for .40/41 anyways so I'm
happy to revert it.
Signed-off-by: Dave Airlie <airlied@redhat.com>
This reverts commit 5a893fc28f.
This causes a use after free in the ttm free alloc pages path,
when it tries to get the be after the be has been destroyed.
Signed-off-by: Dave Airlie <airlied@redhat.com>
This makes the accounting when using 'debug_dma_dump_mappings()'
and CONFIG_DMA_API_DEBUG=y be assigned to the correct device
instead of 'fallback'.
No functional change - just cosmetic.
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
For pages that have the TTM_PAGE_FLAG_DMA32 flag set we
use the DMA API. We save the bus address in our array which we
use to program the GART (see "radeon/ttm/PCIe: Use dma_addr if TTM
has set it." and "nouveau/ttm/PCIe: Use dma_addr if TTM has set it.").
The reason behind using the DMA API is that under Xen we would
end up programming the GART with the bounce buffer (SWIOTLB)
DMA address instead of the physical DMA address of the TTM page.
The reason being that alloc_page with GFP_DMA32 does not allocate
pages under the the 4GB mark when running under Xen hypervisor.
Under baremetal this means we do the DMA API call earlier instead
of when we program the GART.
For details please refer to:
https://lkml.org/lkml/2011/1/7/251
[v2: Fixed indentation, revised desc, added Reviewed-by]
Reviewed-by: Thomas Hellstrom <thomas@shipmail.org>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Tested-by: Ian Campbell <ian.campbell@citrix.com>
This is right now limited to only non-pool constructs.
[v2: Fixed indentation issues, add review-by tag]
Reviewed-by: Thomas Hellstrom <thomas@shipmail.org>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Tested-by: Ian Campbell <ian.campbell@citrix.com>
Correct allocation flags type and function prototype for ANSI C compliance.
[airlied: whitespace fixed]
Signed-off-by: Daniel J Blueman <daniel.blueman@gmail.com>
Reviewed-by: Alex Deucher <alexdeucher@gmail.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
* 'drm-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/airlied/drm-2.6:
drm/radeon/kms: add quirk to make HP DV5000 laptop resume
drm/radeon/kms: fix RADEON_INFO_CRTC_FROM_ID info ioctl
Fix ttm_page_alloc.c build breakage
drm/radeon/kms: fix legacy LVDS dpms sequence
drm/radeon/kms: drop taking lock around crtc lookup.
The commit 1e8655f873
drm/ttm: Fix build on architectures without AGP
looks at TTM_HAS_AGP before it has been set in ttm_bo_driver.h
Move the conditional inclusion of <asm/agp.h> *after* we have included
ttm_bo_driver.h
Signed-of-by: Tony Luck <tony.luck@intel.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Add the shrinkers missed in the first conversion of the API in
commit 7f8275d0d6 ("mm: add context argument to
shrinker callback").
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Make inclusion of <asm/agp.h> conditional on TTM_HAS_AGP. The use
of the functions declared in it is already conditional.
Reported-by: Geert Stappers <stappers@stappers.nl>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Tested-by: Geert Stappers <stappers@stappers.nl>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Repeated ttm_page_alloc_init/fini fails noisily because the pool
manager kobj isn't zeroed out between uses (we could do just that but
statically allocated kobjects are generally considered a bad thing).
Move it to kzalloc'ed memory.
Note that this patch drops the refcounting behavior of the pool
allocator init/fini functions: it would have led to a race condition
in its current form, and anyway it was never exploited.
This fixes a regression with reloading kms modules at runtime, since
page allocator was introduced.
Signed-off-by: Francisco Jerez <currojerez@riseup.net>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Non pooled page allocation should have GFP_USER set so allocation
can wait and reclaim page from other process (ie non atomic).
Signed-off-by: Jerome Glisse <jglisse@redhat.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Fix a number of typos misspellings and checkpatch.pl warnings.
Replace "[ttm] " with TTM_PFX
Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
This patch fixes a regression introduced with the pool page allocator
in the event that there are no highmem pages (for example x86_64),
in which case cached page allocation would fail.
Tested with the vmwgfx driver on a 64-bit vm.
Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Fixes
drivers/gpu/drm/ttm/ttm_page_alloc.c: In function 'ttm_page_alloc_debugfs':
drivers/gpu/drm/ttm/ttm_page_alloc.c:829: error: implicit declaration of
function 'seq_printf'
Signed-off-by: Matt Turner <mattst88@gmail.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Sysfs interface allows user to configure pool allocator functionality and
change limits for the size of pool.
Signed-off-by: Pauli Nieminen <suokkos@gmail.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Using single call to set multiple pages to wc reduces number of expensive cache
flushes.
Signed-off-by: Pauli Nieminen <suokkos@gmail.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
ttm_page_alloc_debugfs can be registered to output the state
of pools.
Debugfs file will output number of pages freed from the pool,
number of pages in pool now and the lowes number of pages in
pool since previous shrink.
Signed-off-by: Pauli Nieminen <suokkos@gmail.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
On AGP system we might allocate/free routinely uncached or wc memory,
changing page from cached (wb) to uc or wc is very expensive and involves
a lot of flushing. To improve performance this allocator use a pool
of uc,wc pages.
Pools are protected with spinlocks to allow multiple threads to allocate pages
simultanously. Expensive operations are done outside of spinlock to maximize
concurrency.
Pools are linked lists of pages that were recently freed. mm shrink callback
allows kernel to claim back pages when they are required for something else.
Fixes:
* set_pages_array_wb handles highmem pages so we don't have to remove them
from pool.
* Add count parameter to ttm_put_pages to avoid looping in free code.
* Change looping from _safe to normal in pool fill error path.
* Initialize sum variable and make the loop prettier in get_num_unused_pages.
* Moved pages_freed reseting inside the loop in ttm_page_pool_free.
* Add warning comment about spinlock context in ttm_page_pool_free.
Based on Jerome Glisse's and Dave Airlie's pool allocator.
Signed-off-by: Jerome Glisse <jglisse@redhat.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Signed-off-by: Pauli Nieminen <suokkos@gmail.com>
Reviewed-by: Jerome Glisse <jglisse@redhat.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
