The set_need_resched() removal fix and yet another fix in
ttm_bo_move_memcpy().
* 'ttm-fixes-3.13' of git://people.freedesktop.org/~thomash/linux:
drm/ttm: Remove set_need_resched from the ttm fault handler
drm/ttm: Don't move non-existing data
Addresses
"[BUG] completely bonkers use of set_need_resched + VM_FAULT_NOPAGE".
In the first occurence it was used to try to be nice while releasing the
mmap_sem and retrying the fault to work around a locking inversion.
The second occurence was never used.
There has been some discussion whether we should change the locking order to
mmap_sem -> bo_reserve. This patch doesn't address that issue, and leaves
that locking order undefined. The solution that we release the mmap_sem if
tryreserve fails and wait for the buffer to become unreserved is something
we want in any case, and follows how the core vm system waits for pages
to be come unlocked while releasing the mmap_sem.
The code also outlines what needs to be changed if we want to establish the
locking order as mmap_sem -> bo::reserve.
One slight issue that remains with this code is that the fault handler might
be prone to starvation if another thread countinously reserves the buffer.
IMO that usage pattern is highly unlikely.
Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com>
If ttm_bo_move_memcpy was instructed to move a non-populated ttm to
io memory, it would first populate the ttm, then move the data and then
destroy the ttm. That's stupid. However, some drivers might have relied on
this to clear io memory from old stuff. So instead of a NOP, which would
be the most efficient, just clear the destination.
Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com>
Reviewed-by: Jakob Bornecrantz <jakob@vmware.com>
If no reservation ticket is given to the execbuf reservation utilities,
try reservation with non-blocking semantics.
This is intended for eviction paths that use the execbuf reservation
utilities for convenience rather than for deadlock avoidance.
Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com>
Reviewed-by: Jakob Bornecrantz <jakob@vmware.com>
Fix a long-standing TTM issue where we manipulated the vma page_prot
bits while mmap_sem was taken in read mode only. We now make a local
copy of the vma structure which we pass when we set the ptes.
Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com>
Reviewed-by: Jerome Glisse <jglisse@redhat.com>
- A couple of fixes that never made it into fixes-3.12
- Make NO_EVICT bo's available for shrinkers when on delayed-delete list
- Allow retrying page-faults that need to wait for GPU.
* 'ttm-next-3.13' of git://people.freedesktop.org/~thomash/linux:
drm/ttm: Fix memory type compatibility check
drm/ttm: Fix ttm_bo_move_memcpy
drm/ttm: Handle in-memory region copies
drm/ttm: Make NO_EVICT bos available to shrinkers pending destruction
drm/ttm: Allow vm fault retries
Also check the busy placements before deciding to move a buffer object.
Failing to do this may result in a completely unneccessary move within a
single memory type.
Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com>
Reviewed-by: Jakob Bornecrantz <jakob@vmware.com>
Cc: stable@vger.kernel.org
All error paths will want to keep the mm node, so handle this at the
function exit. This fixes an ioremap failure error path.
Also add some comments to make the function a bit easier to understand.
Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com>
Reviewed-by: Jakob Bornecrantz <jakob@vmware.com>
Cc: stable@vger.kernel.org
Fix the case where the ttm pointer may be NULL causing
a NULL pointer dereference.
Signed-off-by: Jakob Bornecrantz <jakob@vmware.com>
Signed-off-by: Thomas Hellström <thellstrom@vmware.com>
Cc: stable@vger.kernel.org
NO_EVICT bos that are not idle when all references are dropped are put on
the delayed destroy list. However, since they are not on LRU lists, they
are not available to shrinkers at that point, and buffers on the delayed
destroy list are not checked very often for idle.
So when these buffers are put on the delayed destroy list, clear the
NO_EVICT flag and put them on the right LRU list. This way they are
immediately available for eviction or shrinkers and will not cause false
OOMS.
Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com>
Reviewed-by: Jakob Bornecrantz <jakob@vmware.com>
Make use of the FAULT_FLAG_ALLOW_RETRY flag to allow dropping the
mmap_sem while waiting for bo idle.
FAULT_FLAG_ALLOW_RETRY appears to be primarily designed for disk waits
but should work just as fine for GPU waits..
Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com>
Reviewed-by: Jakob Bornecrantz <jakob@vmware.com>
Used by the vmwgfx driver
Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com>
Reviewed-by: Jakob Bornecrantz <jakob@vmware.com>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Pull drm radeon/nouveau/core fixes from Dave Airlie:
"Mostly radeon fixes, with some nouveau bios parser, ttm fix and a fix
for AST driver"
* 'drm-fixes' of git://people.freedesktop.org/~airlied/linux: (42 commits)
drm/fb-helper: don't sleep for screen unblank when an oops is in progress
drm, ttm Fix uninitialized warning
drm/ttm: fix the tt_populated check in ttm_tt_destroy()
drm/nouveau/ttm: prevent double-free in nouveau_sgdma_create_ttm() failure path
drm/nouveau/bios/init: fix thinko in INIT_CONFIGURE_MEM
drm/nouveau/kms: enable for non-vga pci classes
drm/nouveau/bios/init: stub opcode 0xaa
drm/radeon: avoid UVD corruptions on AGP cards
drm/radeon: fix panel scaling with eDP and LVDS bridges
drm/radeon/dpm: rework auto performance level enable
drm/radeon: Fix hmdi typo
drm/radeon/dpm/rs780: fix force_performance state for same sclks
drm/radeon/dpm/rs780: don't enable sclk scaling if not required
drm/radeon/dpm/rs780: add some sanity checking to sclk scaling
drm/radeon/dpm/rs780: use drm_mode_vrefresh()
drm/udl: rip out set_need_resched
drm/ast: fix the ast open key function
drm/radeon/dpm: add bapm callback for kb/kv
drm/radeon/dpm: add bapm callback for trinity
drm/radeon/dpm: add infrastructure to properly handle bapm
...
Fix uninitialized warning.
drivers/gpu/drm/ttm/ttm_object.c: In function ‘ttm_base_object_lookup’:
drivers/gpu/drm/ttm/ttm_object.c:213:10: error: ‘base’ may be used uninitialized in this function [-Werror=maybe-uninitialized]
kref_put(&base->refcount, ttm_release_base);
^
drivers/gpu/drm/ttm/ttm_object.c:221:26: note: ‘base’ was declared here
struct ttm_base_object *base;
Signed-off-by: Prarit Bhargava <prarit@redhat.com>
Reviewed-by: Rob Clark <robdclark@gmail.com>
Reviewed-by: David Herrmann <dh.herrmann@gmail.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
After a vmalloc failure in ttm_dma_tt_alloc_page_directory(),
ttm_dma_tt_init() will call ttm_tt_destroy() to cleanup, and end up
inside the driver's unpopulate() hook when populate() has never yet
been called.
On nouveau, the first issue to be hit because of this is that
dma_address[] may be a NULL pointer. After working around this,
ttm_pool_unpopulate() may potentially hit the same issue with
the pages[] array.
It seems to make more sense to avoid calling unpopulate on already
unpopulated TTMs than to add checks to all the implementations.
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
Reviewed-by: Thomas Hellstrom <thellstrom@vmware.com>
Cc: stable@vger.kernel.org
Cc: Jerome Glisse <jglisse@redhat.com>
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>
This helper is used only once and just wraps a call to
drm_vma_offset_add(). Remove this unneeded indirection to safe 10 lines of
code.
Signed-off-by: David Herrmann <dh.herrmann@gmail.com>
Reviewed-by: Jerome Glisse <jglisse@redhat.com>
Signed-off-by: Dave Airlie <airlied@gmail.com>
Instead of calling drm_mm_pre_get() in a row, we now preallocate the node
and then use the atomic insertion functions. This has the exact same
semantics and there is no reason to use the racy pre-allocations.
Note that ttm_bo_man_get_node() does not run in atomic context. Nouveau
already uses GFP_KERNEL alloc in nouveau/nouveau_ttm.c in
nouveau_gart_manager_new(). So we can do the same in
ttm_bo_man_get_node().
Signed-off-by: David Herrmann <dh.herrmann@gmail.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Add a "best_match" flag similar to the drm_mm_search_*() helpers so we
can convert TTM to use them in follow up patches. We can also inline the
non-generic helpers and move them into the header to allow compile-time
optimizations.
To make calls to drm_mm_{search,insert}_node() more readable, this
converts the boolean argument to a flagset. There are pending patches that
add additional flags for top-down allocators and more.
v2:
- use flag parameter instead of boolean "best_match"
- convert *_search_free() helpers to also use flags argument
Signed-off-by: David Herrmann <dh.herrmann@gmail.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Instead of unmapping the nodes in TTM and GEM users manually, we provide
a generic wrapper which does the correct thing for all vma-nodes.
v2: remove bdev->dev_mapping test in ttm_bo_unmap_virtual_unlocked() as
ttm_mem_io_free_vm() does nothing in that case (io_reserved_vm is 0).
v4: Fix docbook comments
v5: use drm_vma_node_size()
Cc: Dave Airlie <airlied@redhat.com>
Cc: Maarten Lankhorst <maarten.lankhorst@canonical.com>
Cc: Thomas Hellstrom <thellstrom@vmware.com>
Signed-off-by: David Herrmann <dh.herrmann@gmail.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Dave Airlie <airlied@gmail.com>
Use the new vma-manager infrastructure. This doesn't change any
implementation details as the vma-offset-manager is nearly copied 1-to-1
from TTM.
The vm_lock is moved into the offset manager so we can drop it from TTM.
During lookup, we use the vma locking helpers to take a reference to the
found object.
In all other scenarios, locking stays the same as before. We always
guarantee that drm_vma_offset_remove() is called only during destruction.
Hence, helpers like drm_vma_node_offset_addr() are always safe as long as
the node has a valid offset.
This also drops the addr_space_offset member as it is a copy of vm_start
in vma_node objects. Use the accessor functions instead.
v4:
- remove vm_lock
- use drm_vma_offset_lock_lookup() to protect lookup (instead of vm_lock)
Cc: Dave Airlie <airlied@redhat.com>
Cc: Ben Skeggs <bskeggs@redhat.com>
Cc: Maarten Lankhorst <maarten.lankhorst@canonical.com>
Cc: Martin Peres <martin.peres@labri.fr>
Cc: Alex Deucher <alexander.deucher@amd.com>
Cc: Thomas Hellstrom <thellstrom@vmware.com>
Signed-off-by: David Herrmann <dh.herrmann@gmail.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Dave Airlie <airlied@gmail.com>
There is no reason to return "int" as this function never fails.
Furthermore, several drivers (ast, sis) already depend on this.
Signed-off-by: David Herrmann <dh.herrmann@gmail.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Now that the code is compatible in semantics, flip the switch.
Use ww_mutex instead of the homegrown implementation.
ww_mutex uses -EDEADLK to signal that the caller has to back off,
and -EALREADY to indicate this buffer is already held by the caller.
ttm used -EAGAIN and -EDEADLK for those, respectively. So some changes
were needed to handle this correctly.
Signed-off-by: Maarten Lankhorst <maarten.lankhorst@canonical.com>
Reviewed-by: Jerome Glisse <jglisse@redhat.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
This commit converts the source of the val_seq counter to
the ww_mutex api. The reservation objects are converted later,
because there is still a lockdep splat in nouveau that has to
resolved first.
Signed-off-by: Maarten Lankhorst <maarten.lankhorst@canonical.com>
Reviewed-by: Jerome Glisse <jglisse@redhat.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
(*->vm_end - *->vm_start) >> PAGE_SHIFT operation is implemented
as a inline funcion vma_pages() in linux/mm.h, so using it.
Signed-off-by: Libin <huawei.libin@huawei.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
qxl wants to use io mapping like i915 gem does, for now
just export the symbols so the driver can implement atomic
page maps using io mapping.
Signed-off-by: Dave Airlie <airlied@redhat.com>
Pull vfs pile (part one) from Al Viro:
"Assorted stuff - cleaning namei.c up a bit, fixing ->d_name/->d_parent
locking violations, etc.
The most visible changes here are death of FS_REVAL_DOT (replaced with
"has ->d_weak_revalidate()") and a new helper getting from struct file
to inode. Some bits of preparation to xattr method interface changes.
Misc patches by various people sent this cycle *and* ocfs2 fixes from
several cycles ago that should've been upstream right then.
PS: the next vfs pile will be xattr stuff."
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (46 commits)
saner proc_get_inode() calling conventions
proc: avoid extra pde_put() in proc_fill_super()
fs: change return values from -EACCES to -EPERM
fs/exec.c: make bprm_mm_init() static
ocfs2/dlm: use GFP_ATOMIC inside a spin_lock
ocfs2: fix possible use-after-free with AIO
ocfs2: Fix oops in ocfs2_fast_symlink_readpage() code path
get_empty_filp()/alloc_file() leave both ->f_pos and ->f_version zero
target: writev() on single-element vector is pointless
export kernel_write(), convert open-coded instances
fs: encode_fh: return FILEID_INVALID if invalid fid_type
kill f_vfsmnt
vfs: kill FS_REVAL_DOT by adding a d_weak_revalidate dentry op
nfsd: handle vfs_getattr errors in acl protocol
switch vfs_getattr() to struct path
default SET_PERSONALITY() in linux/elf.h
ceph: prepopulate inodes only when request is aborted
d_hash_and_lookup(): export, switch open-coded instances
9p: switch v9fs_set_create_acl() to inode+fid, do it before d_instantiate()
9p: split dropping the acls from v9fs_set_create_acl()
...
Pull drm merge from Dave Airlie:
"Highlights:
- TI LCD controller KMS driver
- TI OMAP KMS driver merged from staging
- drop gma500 stub driver
- the fbcon locking fixes
- the vgacon dirty like zebra fix.
- open firmware videomode and hdmi common code helpers
- major locking rework for kms object handling - pageflip/cursor
won't block on polling anymore!
- fbcon helper and prime helper cleanups
- i915: all over the map, haswell power well enhancements, valleyview
macro horrors cleaned up, killing lots of legacy GTT code,
- radeon: CS ioctl unification, deprecated UMS support, gpu reset
rework, VM fixes
- nouveau: reworked thermal code, external dp/tmds encoder support
(anx9805), fences sleep instead of polling,
- exynos: all over the driver fixes."
Lovely conflict in radeon/evergreen_cs.c between commit de0babd60d
("drm/radeon: enforce use of radeon_get_ib_value when reading user cmd")
and the new changes that modified that evergreen_dma_cs_parse()
function.
* 'drm-next' of git://people.freedesktop.org/~airlied/linux: (508 commits)
drm/tilcdc: only build on arm
drm/i915: Revert hdmi HDP pin checks
drm/tegra: Add list of framebuffers to debugfs
drm/tegra: Fix color expansion
drm/tegra: Split DC_CMD_STATE_CONTROL register write
drm/tegra: Implement page-flipping support
drm/tegra: Implement VBLANK support
drm/tegra: Implement .mode_set_base()
drm/tegra: Add plane support
drm/tegra: Remove bogus tegra_framebuffer structure
drm: Add consistency check for page-flipping
drm/radeon: Use generic HDMI infoframe helpers
drm/tegra: Use generic HDMI infoframe helpers
drm: Add EDID helper documentation
drm: Add HDMI infoframe helpers
video: Add generic HDMI infoframe helpers
drm: Add some missing forward declarations
drm: Move mode tables to drm_edid.c
drm: Remove duplicate drm_mode_cea_vic()
gma500: Fix n, m1 and m2 clock limits for sdvo and lvds
...
TTM reservations changes, preparing for new reservation mutex system.
* 'for-airlied' of git://people.freedesktop.org/~mlankhorst/linux:
drm/ttm: unexport ttm_bo_wait_unreserved
drm/nouveau: use ttm_bo_reserve_slowpath in validate_init, v2
drm/ttm: use ttm_bo_reserve_slowpath_nolru in ttm_eu_reserve_buffers, v2
drm/ttm: add ttm_bo_reserve_slowpath
drm/ttm: cleanup ttm_eu_reserve_buffers handling
drm/ttm: remove lru_lock around ttm_bo_reserve
drm/nouveau: increase reservation sequence every retry
drm/vmwgfx: always use ttm_bo_is_reserved
This fixes up
commit e8e89622ed
Author: Daniel Vetter <daniel.vetter@ffwll.ch>
Date: Tue Dec 18 22:25:11 2012 +0100
drm/ttm: fix fence locking in ttm_buffer_object_transfer
which leaves behind a might_sleep in atomic context, since the
fence_lock spinlock is held over a kmalloc(GFP_KERNEL) call. The fix
is to revert the above commit and only take the lock where we need it,
around the call to ->sync_obj_ref.
v2: Fixup things noticed by Maarten Lankhorst:
- Brown paper bag locking bug.
- No need for kzalloc if we clear the entire thing on the next line.
- check for bo->sync_obj (totally unlikely race, but still someone
else could have snuck in) and clear fbo->sync_obj if it's cleared
already.
Reported-by: Dave Airlie <airlied@gmail.com>
Cc: Jerome Glisse <jglisse@redhat.com>
Cc: Maarten Lankhorst <maarten.lankhorst@canonical.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Dave Airlie <airlied@redhat.com>
if we have a move notify callback, when moving fails, we call move notify
the opposite way around, however this ends up with *mem containing the mm_node
from the bo, which means we double free it. This is a follow on to the previous
fix.
Reviewed-by: Jerome Glisse <jglisse@redhat.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
When we are using memcpy to move objects around, and we fail to memcpy
due to lack of memory to populate or failure to finish the copy, we don't
want to destroy the mm_node that has been copied into old_copy.
While working on a new kms driver that uses memcpy, if I overallocated bo's
up to the memory limits, and eviction failed, then machine would oops soon
after due to having an active bo with an already freed drm_mm embedded in it,
freeing it a second time didn't end well.
Reviewed-by: Jerome Glisse <jglisse@redhat.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
All legitimate users of this function outside ttm_bo.c are gone, now
it's only an implementation detail.
Signed-off-by: Maarten Lankhorst <maarten.lankhorst@canonical.com>
Reviewed-by: Jerome Glisse <jglisse@redhat.com>
This requires re-use of the seqno, which increases fairness slightly.
Instead of spinning with a new seqno every time we keep the current one,
but still drop all other reservations we hold. Only when we succeed,
we try to get back our other reservations again.
This should increase fairness slightly as well.
Changes since v1:
- Increase val_seq before calling ttm_bo_reserve_slowpath_nolru and
retrying to take all entries to prevent a race.
Signed-off-by: Maarten Lankhorst <maarten.lankhorst@canonical.com>
Reviewed-by: Jerome Glisse <jglisse@redhat.com>
Instead of dropping everything, waiting for the bo to be unreserved
and trying over, a better strategy would be to do a blocking wait.
This can be mapped a lot better to a mutex_lock-like call.
Signed-off-by: Maarten Lankhorst <maarten.lankhorst@canonical.com>
Reviewed-by: Jerome Glisse <jglisse@redhat.com>
With the lru lock no longer required for protecting reservations we
can just do a ttm_bo_reserve_nolru on -EBUSY, and handle all errors
in a single path.
Signed-off-by: Maarten Lankhorst <maarten.lankhorst@canonical.com>
Reviewed-by: Jerome Glisse <jglisse@redhat.com>
There should no longer be assumptions that reserve will always succeed
with the lru lock held, so we can safely break the whole atomic
reserve/lru thing. As a bonus this fixes most lockdep annotations for
reservations.
Signed-off-by: Maarten Lankhorst <maarten.lankhorst@canonical.com>
Reviewed-by: Jerome Glisse <jglisse@redhat.com>
Noticed while reviewing the fence locking in the radeon pageflip
handler.
v2: Instead of grabbing the bdev->fence_lock in object_transfer just
move the single callsite of that function a few lines, so that it is
protected by the fence_lock. Suggested by Jerome Glisse.
v3: Fix typo in commit message.
Reviewed-by: Jerome Glisse <jglisse@redhat.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Dave Airlie <airlied@redhat.com>
All items on the lru list are always reservable, so this is a stupid
thing to keep. Not only that, it is used in a way which would
guarantee deadlocks if it were ever to be set to block on reserve.
This is a lot of churn, but mostly because of the removal of the
argument which can be nested arbitrarily deeply in many places.
No change of code in this patch except removal of the no_wait_reserve
argument, the previous patch removed the use of no_wait_reserve.
v2:
- Warn if -EBUSY is returned on reservation, all objects on the list
should be reservable. Adjusted patch slightly due to conflicts.
v3:
- Focus on no_wait_reserve removal only.
Signed-off-by: Maarten Lankhorst <maarten.lankhorst@canonical.com>
Reviewed-by: Thomas Hellstrom <thellstrom@vmware.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Replace the goto loop with a simple for each loop, and only run the
delayed destroy cleanup if we can reserve the buffer first.
No race occurs, since lru lock is never dropped any more. An empty list
and a list full of unreservable buffers both cause -EBUSY to be returned,
which is identical to the previous situation, because previously buffers
on the lru list were always guaranteed to be reservable.
This should work since currently ttm guarantees items on the lru are
always reservable, and reserving items blockingly with some bo held
are enough to cause you to run into a deadlock.
Currently this is not a concern since removal off the lru list and
reservations are always done with atomically, but when this guarantee
no longer holds, we have to handle this situation or end up with
possible deadlocks.
Signed-off-by: Maarten Lankhorst <maarten.lankhorst@canonical.com>
Reviewed-by: Thomas Hellstrom <thellstrom@vmware.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Replace the while loop with a simple for each loop, and only run the
delayed destroy cleanup if we can reserve the buffer first.
No race occurs, since lru lock is never dropped any more. An empty list
and a list full of unreservable buffers both cause -EBUSY to be returned,
which is identical to the previous situation.
Signed-off-by: Maarten Lankhorst <maarten.lankhorst@canonical.com>
Reviewed-by: Thomas Hellstrom <thellstrom@vmware.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
By removing the unlocking of lru and retaking it immediately, a race is
removed where the bo is taken off the swap list or the lru list between
the unlock and relock. As such the cleanup_refs code can be simplified,
it will attempt to call ttm_bo_wait non-blockingly, and if it fails
it will drop the locks and perform a blocking wait, or return an error
if no_wait_gpu was set.
The need for looping is also eliminated, since swapout and evict_mem_first
will always follow the destruction path, no new fence is allowed
to be attached. As far as I can see this may already have been the case,
but the unlocking / relocking required a complicated loop to deal with
re-reservation.
Changes since v1:
- Simplify no_wait_gpu case by folding it in with empty ddestroy.
- Hold a reservation while calling ttm_bo_cleanup_memtype_use again.
Changes since v2:
- Do not remove bo from lru list while waiting
Signed-off-by: Maarten Lankhorst <maarten.lankhorst@canonical.com>
Reviewed-by: Thomas Hellstrom <thellstrom@vmware.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
This requires changing the order in ttm_bo_cleanup_refs_or_queue to
take the reservation first, as there is otherwise no race free way to
take lru lock before fence_lock.
Signed-off-by: Maarten Lankhorst <maarten.lankhorst@canonical.com>
Reviewed-by: Thomas Hellstrom <thellstrom@vmware.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Dave Airlie