We free objects in bulk after they wait for their RCU grace period.
Currently, we take struct_mutex and unbind all the objects. This can lead
to a long lock duration during which time those objects have their pages
unfreeable (i.e. the shrinker is prevented from reaping those pages). If
we only process a single object under the struct_mutex and then free the
pages, the number of objects locked away from the shrinker is minimal
and we allow regular clients better access to struct_mutex if they need
it.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20171013202621.7276-9-chris@chris-wilson.co.uk
Inspired by Tvrtko's critique of the reaping of the stale contexts
before allocating a new one, also limit the freed object reaping to the
oldest stale object before allocating a fresh object. Unlike contexts,
objects may have radically different sizes of backing storage, but
similar to contexts, while we want to prevent starvation due to
excessive freed lists, we also do not want to delay fresh allocations
for too long. Only freeing the oldest on the freed object list before
each allocation is a reasonable compromise.
v2: Only a single consumer of llist_del_first() is allowed (although
multiple llist_add are still allowed in parallel). Unlike
i915_gem_context, i915_gem_flush_free_objects() is itself not serialized
and so we need to add our own spinlock. Otherwise KASAN eventually spots
a use-after-free for the race on *first->next.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com> #v1
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20171013202621.7276-8-chris@chris-wilson.co.uk
Remove the struct_mutex requirement around dev_priv->mm.bound_list and
dev_priv->mm.unbound_list by giving it its own spinlock. This reduces
one more requirement for struct_mutex and in the process gives us
slightly more accurate unbound_list tracking, which should improve the
shrinker - but the drawback is that we drop the retirement before
counting so i915_gem_object_is_active() may be stale and lead us to
underestimate the number of objects that may be shrunk (see commit
bed50aea61 ("drm/i915/shrinker: Flush active on objects before
counting")).
v2: Crosslink the spinlock to the lists it protects, and btw this
changes s/obj->global_link/obj->mm.link/
v3: Fix decoupling of old links in i915_gem_object_attach_phys()
v3.1: Fix the fix, only unlink if it was linked
v3.2: Use a local for to_i915(obj->base.dev)->mm.obj_lock
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20171016114037.5556-1-chris@chris-wilson.co.uk
stop_machine is not really a locking primitive we should use, except
when the hw folks tell us the hw is broken and that's the only way to
work around it.
This patch tries to address the locking abuse of stop_machine() from
commit 20e4933c47
Author: Chris Wilson <chris@chris-wilson.co.uk>
Date: Tue Nov 22 14:41:21 2016 +0000
drm/i915: Stop the machine as we install the wedged submit_request handler
Chris said parts of the reasons for going with stop_machine() was that
it's no overhead for the fast-path. But these callbacks use irqsave
spinlocks and do a bunch of MMIO, and rcu_read_lock is _real_ fast.
To stay as close as possible to the stop_machine semantics we first
update all the submit function pointers to the nop handler, then call
synchronize_rcu() to make sure no new requests can be submitted. This
should give us exactly the huge barrier we want.
I pondered whether we should annotate engine->submit_request as __rcu
and use rcu_assign_pointer and rcu_dereference on it. But the reason
behind those is to make sure the compiler/cpu barriers are there for
when you have an actual data structure you point at, to make sure all
the writes are seen correctly on the read side. But we just have a
function pointer, and .text isn't changed, so no need for these
barriers and hence no need for annotations.
Unfortunately there's a complication with the call to
intel_engine_init_global_seqno:
- Without stop_machine we must hold the corresponding spinlock.
- Without stop_machine we must ensure that all requests are marked as
having failed with dma_fence_set_error() before we call it. That
means we need to split the nop request submission into two phases,
both synchronized with rcu:
1. Only stop submitting the requests to hw and mark them as failed.
2. After all pending requests in the scheduler/ring are suitably
marked up as failed and we can force complete them all, also force
complete by calling intel_engine_init_global_seqno().
This should fix the followwing lockdep splat:
======================================================
WARNING: possible circular locking dependency detected
4.14.0-rc3-CI-CI_DRM_3179+ #1 Tainted: G U
------------------------------------------------------
kworker/3:4/562 is trying to acquire lock:
(cpu_hotplug_lock.rw_sem){++++}, at: [<ffffffff8113d4bc>] stop_machine+0x1c/0x40
but task is already holding lock:
(&dev->struct_mutex){+.+.}, at: [<ffffffffa0136588>] i915_reset_device+0x1e8/0x260 [i915]
which lock already depends on the new lock.
the existing dependency chain (in reverse order) is:
-> #6 (&dev->struct_mutex){+.+.}:
__lock_acquire+0x1420/0x15e0
lock_acquire+0xb0/0x200
__mutex_lock+0x86/0x9b0
mutex_lock_interruptible_nested+0x1b/0x20
i915_mutex_lock_interruptible+0x51/0x130 [i915]
i915_gem_fault+0x209/0x650 [i915]
__do_fault+0x1e/0x80
__handle_mm_fault+0xa08/0xed0
handle_mm_fault+0x156/0x300
__do_page_fault+0x2c5/0x570
do_page_fault+0x28/0x250
page_fault+0x22/0x30
-> #5 (&mm->mmap_sem){++++}:
__lock_acquire+0x1420/0x15e0
lock_acquire+0xb0/0x200
__might_fault+0x68/0x90
_copy_to_user+0x23/0x70
filldir+0xa5/0x120
dcache_readdir+0xf9/0x170
iterate_dir+0x69/0x1a0
SyS_getdents+0xa5/0x140
entry_SYSCALL_64_fastpath+0x1c/0xb1
-> #4 (&sb->s_type->i_mutex_key#5){++++}:
down_write+0x3b/0x70
handle_create+0xcb/0x1e0
devtmpfsd+0x139/0x180
kthread+0x152/0x190
ret_from_fork+0x27/0x40
-> #3 ((complete)&req.done){+.+.}:
__lock_acquire+0x1420/0x15e0
lock_acquire+0xb0/0x200
wait_for_common+0x58/0x210
wait_for_completion+0x1d/0x20
devtmpfs_create_node+0x13d/0x160
device_add+0x5eb/0x620
device_create_groups_vargs+0xe0/0xf0
device_create+0x3a/0x40
msr_device_create+0x2b/0x40
cpuhp_invoke_callback+0xc9/0xbf0
cpuhp_thread_fun+0x17b/0x240
smpboot_thread_fn+0x18a/0x280
kthread+0x152/0x190
ret_from_fork+0x27/0x40
-> #2 (cpuhp_state-up){+.+.}:
__lock_acquire+0x1420/0x15e0
lock_acquire+0xb0/0x200
cpuhp_issue_call+0x133/0x1c0
__cpuhp_setup_state_cpuslocked+0x139/0x2a0
__cpuhp_setup_state+0x46/0x60
page_writeback_init+0x43/0x67
pagecache_init+0x3d/0x42
start_kernel+0x3a8/0x3fc
x86_64_start_reservations+0x2a/0x2c
x86_64_start_kernel+0x6d/0x70
verify_cpu+0x0/0xfb
-> #1 (cpuhp_state_mutex){+.+.}:
__lock_acquire+0x1420/0x15e0
lock_acquire+0xb0/0x200
__mutex_lock+0x86/0x9b0
mutex_lock_nested+0x1b/0x20
__cpuhp_setup_state_cpuslocked+0x53/0x2a0
__cpuhp_setup_state+0x46/0x60
page_alloc_init+0x28/0x30
start_kernel+0x145/0x3fc
x86_64_start_reservations+0x2a/0x2c
x86_64_start_kernel+0x6d/0x70
verify_cpu+0x0/0xfb
-> #0 (cpu_hotplug_lock.rw_sem){++++}:
check_prev_add+0x430/0x840
__lock_acquire+0x1420/0x15e0
lock_acquire+0xb0/0x200
cpus_read_lock+0x3d/0xb0
stop_machine+0x1c/0x40
i915_gem_set_wedged+0x1a/0x20 [i915]
i915_reset+0xb9/0x230 [i915]
i915_reset_device+0x1f6/0x260 [i915]
i915_handle_error+0x2d8/0x430 [i915]
hangcheck_declare_hang+0xd3/0xf0 [i915]
i915_hangcheck_elapsed+0x262/0x2d0 [i915]
process_one_work+0x233/0x660
worker_thread+0x4e/0x3b0
kthread+0x152/0x190
ret_from_fork+0x27/0x40
other info that might help us debug this:
Chain exists of:
cpu_hotplug_lock.rw_sem --> &mm->mmap_sem --> &dev->struct_mutex
Possible unsafe locking scenario:
CPU0 CPU1
---- ----
lock(&dev->struct_mutex);
lock(&mm->mmap_sem);
lock(&dev->struct_mutex);
lock(cpu_hotplug_lock.rw_sem);
*** DEADLOCK ***
3 locks held by kworker/3:4/562:
#0: ("events_long"){+.+.}, at: [<ffffffff8109c64a>] process_one_work+0x1aa/0x660
#1: ((&(&i915->gpu_error.hangcheck_work)->work)){+.+.}, at: [<ffffffff8109c64a>] process_one_work+0x1aa/0x660
#2: (&dev->struct_mutex){+.+.}, at: [<ffffffffa0136588>] i915_reset_device+0x1e8/0x260 [i915]
stack backtrace:
CPU: 3 PID: 562 Comm: kworker/3:4 Tainted: G U 4.14.0-rc3-CI-CI_DRM_3179+ #1
Hardware name: /NUC7i5BNB, BIOS BNKBL357.86A.0048.2017.0704.1415 07/04/2017
Workqueue: events_long i915_hangcheck_elapsed [i915]
Call Trace:
dump_stack+0x68/0x9f
print_circular_bug+0x235/0x3c0
? lockdep_init_map_crosslock+0x20/0x20
check_prev_add+0x430/0x840
? irq_work_queue+0x86/0xe0
? wake_up_klogd+0x53/0x70
__lock_acquire+0x1420/0x15e0
? __lock_acquire+0x1420/0x15e0
? lockdep_init_map_crosslock+0x20/0x20
lock_acquire+0xb0/0x200
? stop_machine+0x1c/0x40
? i915_gem_object_truncate+0x50/0x50 [i915]
cpus_read_lock+0x3d/0xb0
? stop_machine+0x1c/0x40
stop_machine+0x1c/0x40
i915_gem_set_wedged+0x1a/0x20 [i915]
i915_reset+0xb9/0x230 [i915]
i915_reset_device+0x1f6/0x260 [i915]
? gen8_gt_irq_ack+0x170/0x170 [i915]
? work_on_cpu_safe+0x60/0x60
i915_handle_error+0x2d8/0x430 [i915]
? vsnprintf+0xd1/0x4b0
? scnprintf+0x3a/0x70
hangcheck_declare_hang+0xd3/0xf0 [i915]
? intel_runtime_pm_put+0x56/0xa0 [i915]
i915_hangcheck_elapsed+0x262/0x2d0 [i915]
process_one_work+0x233/0x660
worker_thread+0x4e/0x3b0
kthread+0x152/0x190
? process_one_work+0x660/0x660
? kthread_create_on_node+0x40/0x40
ret_from_fork+0x27/0x40
Setting dangerous option reset - tainting kernel
i915 0000:00:02.0: Resetting chip after gpu hang
Setting dangerous option reset - tainting kernel
i915 0000:00:02.0: Resetting chip after gpu hang
v2: Have 1 global synchronize_rcu() barrier across all engines, and
improve commit message.
v3: We need to protect the seqno update with the timeline spinlock (in
set_wedged) to avoid racing with other updates of the seqno, like we
already do in nop_submit_request (Chris).
v4: Use two-phase sequence to plug the race Chris spotted where we can
complete requests before they're marked up with -EIO.
v5: Review from Chris:
- simplify nop_submit_request.
- Add comment to rcu_read_lock section.
- Align comments with the new style.
v6: Remove unused variable to appease CI.
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=102886
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=103096
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Mika Kuoppala <mika.kuoppala@intel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Marta Lofstedt <marta.lofstedt@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20171011091019.1425-1-daniel.vetter@ffwll.ch
Currently, we reject attempting to pin a large bo into the mappable
aperture, but only after trying to create the vma. Under debug kernels,
repeatedly creating and freeing that vma for an oversized bo consumes
one-third of the runtime for pwrite/pread tests as it is spent on
kmalloc/kfree tracking. If we move the rejection to before creating that
vma, we lose some accuracy of checking against the fence_size as opposed
to object size, though the fence can never be smaller than the object.
Note that the vma creation itself will reject an attempt to create a vma
larger than the GTT so we can remove one redundant test.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20171009084401.29090-7-chris@chris-wilson.co.uk
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Both pread/pwrite GTT paths provide a fast fallback in case we cannot
map the whole object at a time. Currently, we use the fallback for very
large objects and for active objects that would require remapping, but
we can also add active fault mappable objects to the list that we want
to avoid evicting. The rationale is that such fault mappable objects are
in active use and to evict requires tearing down the CPU PTE and forcing
a page fault on the next access; more costly, and intefers with other
processes, than our per-page GTT fallback.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20171009084401.29090-6-chris@chris-wilson.co.uk
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Resetting the engine requires us to hold the forcewake wakeref to
prevent RC6 trying to happen in the middle of the reset sequence. The
consequence of an unwanted RC6 event in the middle is that random state
is then saved to the powercontext and restored later, which may
overwrite the mmio state we need to preserve (e.g. PD_DIR_BASE in the
legacy ringbuffer reset_ring_common()).
This was noticed in the live_hangcheck selftests when Haswell would
sporadically fail to restart during igt_reset_queue().
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20171009110301.21705-3-chris@chris-wilson.co.uk
Reviewed-by: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Getting started with v4.15 features:
- Cannonlake workarounds (Rodrigo, Oscar)
- Infoframe refactoring and fixes to enable infoframes for DP (Ville)
- VBT definition updates (Jani)
- Sparse warning fixes (Ville, Chris)
- Crtc state usage fixes and cleanups (Ville)
- DP vswing, pre-emph and buffer translation refactoring and fixes (Rodrigo)
- Prevent IPS from interfering with CRC capture (Ville, Marta)
- Enable Mesa to advertise ARB_timer_query (Nanley)
- Refactor GT number into intel_device_info (Lionel)
- Avoid eDP DP AUX CH timeouts harder (Manasi)
- CDCLK check improvements (Ville)
- Restore GPU clock boost on missed pageflip vblanks (Chris)
- Fence register reservation API for vGPU (Changbin)
- First batch of CCS fixes (Ville)
- Finally, numerous GEM fixes, cleanups and improvements (Chris)
* tag 'drm-intel-next-2017-09-07' of git://anongit.freedesktop.org/git/drm-intel: (100 commits)
drm/i915: Update DRIVER_DATE to 20170907
drm/i915/cnl: WaThrottleEUPerfToAvoidTDBackPressure:cnl(pre-prod)
drm/i915: Lift has-pinned-pages assert to caller of ____i915_gem_object_get_pages
drm/i915: Display WA #1133 WaFbcSkipSegments:cnl, glk
drm/i915/cnl: Allow the reg_read ioctl to read the RCS TIMESTAMP register
drm/i915: Move device_info.has_snoop into the static tables
drm/i915: Disable MI_STORE_DATA_IMM for i915g/i915gm
drm/i915: Re-enable GTT following a device reset
drm/i915/cnp: Wa 1181: Fix Backlight issue
drm/i915: Annotate user relocs with __user
drm/i915: Constify load detect mode
drm/i915/perf: Remove __user from u64 in drm_i915_perf_oa_config
drm/i915: Silence sparse by using gfp_t
drm/i915: io unmap functions want __iomem
drm/i915: Add __rcu to radix tree slot pointer
drm/i915: Wake up the device for the fbdev setup
drm/i915: Add interface to reserve fence registers for vGPU
drm/i915: Use correct path to trace include
drm/i915: Fix the missing PPAT cache attributes on CNL
drm/i915: Fix enum pipe vs. enum transcoder for the PCH transcoder
...
GFP_TEMPORARY was introduced by commit e12ba74d8f ("Group short-lived
and reclaimable kernel allocations") along with __GFP_RECLAIMABLE. It's
primary motivation was to allow users to tell that an allocation is
short lived and so the allocator can try to place such allocations close
together and prevent long term fragmentation. As much as this sounds
like a reasonable semantic it becomes much less clear when to use the
highlevel GFP_TEMPORARY allocation flag. How long is temporary? Can the
context holding that memory sleep? Can it take locks? It seems there is
no good answer for those questions.
The current implementation of GFP_TEMPORARY is basically GFP_KERNEL |
__GFP_RECLAIMABLE which in itself is tricky because basically none of
the existing caller provide a way to reclaim the allocated memory. So
this is rather misleading and hard to evaluate for any benefits.
I have checked some random users and none of them has added the flag
with a specific justification. I suspect most of them just copied from
other existing users and others just thought it might be a good idea to
use without any measuring. This suggests that GFP_TEMPORARY just
motivates for cargo cult usage without any reasoning.
I believe that our gfp flags are quite complex already and especially
those with highlevel semantic should be clearly defined to prevent from
confusion and abuse. Therefore I propose dropping GFP_TEMPORARY and
replace all existing users to simply use GFP_KERNEL. Please note that
SLAB users with shrinkers will still get __GFP_RECLAIMABLE heuristic and
so they will be placed properly for memory fragmentation prevention.
I can see reasons we might want some gfp flag to reflect shorterm
allocations but I propose starting from a clear semantic definition and
only then add users with proper justification.
This was been brought up before LSF this year by Matthew [1] and it
turned out that GFP_TEMPORARY really doesn't have a clear semantic. It
seems to be a heuristic without any measured advantage for most (if not
all) its current users. The follow up discussion has revealed that
opinions on what might be temporary allocation differ a lot between
developers. So rather than trying to tweak existing users into a
semantic which they haven't expected I propose to simply remove the flag
and start from scratch if we really need a semantic for short term
allocations.
[1] http://lkml.kernel.org/r/20170118054945.GD18349@bombadil.infradead.org
[akpm@linux-foundation.org: fix typo]
[akpm@linux-foundation.org: coding-style fixes]
[sfr@canb.auug.org.au: drm/i915: fix up]
Link: http://lkml.kernel.org/r/20170816144703.378d4f4d@canb.auug.org.au
Link: http://lkml.kernel.org/r/20170728091904.14627-1-mhocko@kernel.org
Signed-off-by: Michal Hocko <mhocko@suse.com>
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Acked-by: Mel Gorman <mgorman@suse.de>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Neil Brown <neilb@suse.de>
Cc: "Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull i916 drm fixes from Rodrigo Vivi:
"Since Dave is on paternity leave we are sending drm/i915 fixes for
v4.14-rc1 directly to you as he had asked us to do.
The most critical ones are the GPU reset fix for gen2-4 and GVT fix
for a regression that is blocking gvt init to work on your tree.
The rest is general fixes for patches coming from drm-next"
Acked-by: Dave Airlie <airlied@redhat.com>
* tag 'drm-intel-next-fixes-2017-09-07' of git://anongit.freedesktop.org/git/drm-intel:
drm/i915: Re-enable GTT following a device reset
drm/i915: Annotate user relocs with __user
drm/i915: Silence sparse by using gfp_t
drm/i915: Add __rcu to radix tree slot pointer
drm/i915: Fix the missing PPAT cache attributes on CNL
drm/i915/gvt: Remove one duplicated MMIO
drm/i915: Fix enum pipe vs. enum transcoder for the PCH transcoder
drm/i915: Make i2c lock ops static
drm/i915: Make i9xx_load_ycbcr_conversion_matrix() static
drm/i915/edp: Increase T12 panel delay to 900 ms to fix DP AUX CH timeouts
drm/i915: Ignore duplicate VMA stored within the per-object handle LUT
drm/i915: Skip fence alignemnt check for the CCS plane
drm/i915: Treat fb->offsets[] as a raw byte offset instead of a linear offset
drm/i915: Always wake the device to flush the GTT
drm/i915: Recreate vmapping even when the object is pinned
drm/i915: Quietly cancel FBC activation if CRTC is turned off before worker
drm_pci_alloc() refuses to cooperate if the passed alignment exceeds the
object size. So round up the obj size to the next power of two as well
to make this actually work.
Obviously things work just fine as long as the size was a power of two
to begin with. However kms_cursor_crc doesn't always use power of two
sizes so we hit a failure when we try to allocate the phys memory.
Testcase: igt/kms_cursor_crc
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20170907143203.13055-1-ville.syrjala@linux.intel.com
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
With the addition of __sg_alloc_table_from_pages we can control
the maximum coalescing size and eliminate a separate path for
allocating backing store here.
Similar to 871dfbd67d ("drm/i915: Allow compaction upto
SWIOTLB max segment size") this enables more compact sg lists to
be created and so has a beneficial effect on workloads with many
and/or large objects of this class.
v2:
* Rename helper to i915_sg_segment_size and fix swiotlb override.
* Commit message update.
v3:
* Actually include the swiotlb override fix.
v4:
* Regroup parameters a bit. (Chris Wilson)
v5:
* Rebase for swiotlb_max_segment.
* Add DMA map failure handling as in abb0deacb5
("drm/i915: Fallback to single PAGE_SIZE segments for DMA remapping").
v6: Handle swiotlb_max_segment() returning 1. (Joonas Lahtinen)
v7: Rebase.
v8: Commit spelling fix.
Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: linux-kernel@vger.kernel.org
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20170803091417.23677-1-tvrtko.ursulin@linux.intel.com
radix_tree_for_each_slot() wants an __rcu annotated pointer for the
slot. So let's add the annotation.
Fixes the following sparse warnings:
i915_gem.c:2217:9: warning: incorrect type in assignment (different address spaces)
i915_gem.c:2217:9: expected void **slot
i915_gem.c:2217:9: got void [noderef] <asn:4>**
i915_gem.c:2217:9: warning: incorrect type in assignment (different address spaces)
i915_gem.c:2217:9: expected void **slot
i915_gem.c:2217:9: got void [noderef] <asn:4>**
i915_gem.c:2217:9: warning: incorrect type in argument 1 (different address spaces)
i915_gem.c:2217:9: expected void [noderef] <asn:4>**slot
i915_gem.c:2217:9: got void **slot
i915_gem.c:2217:9: warning: incorrect type in assignment (different address spaces)
i915_gem.c:2217:9: expected void **slot
i915_gem.c:2217:9: got void [noderef] <asn:4>**
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Fixes: 96d7763452 ("drm/i915: Use a radixtree for random access to the object's backing storage")
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20170901171252.31025-1-ville.syrjala@linux.intel.com
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
(cherry picked from commit c23aa71bcf)
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Don't cast away the __iomem from the io_mapping functions so that
sparse won't be so unhappy when we pass the pointer to the unmap
functions. Instead let's move the cast to where we actually use the
pointer.
Fixes the following sparse warnings:
i915_gem.c:1022:33: warning: incorrect type in argument 1 (different address spaces)
i915_gem.c:1022:33: expected void [noderef] <asn:2>*vaddr
i915_gem.c:1022:33: got void *[assigned] vaddr
i915_gem.c:1027:34: warning: incorrect type in argument 1 (different address spaces)
i915_gem.c:1027:34: expected void [noderef] <asn:2>*vaddr
i915_gem.c:1027:34: got void *[assigned] vaddr
i915_gem.c:1199:33: warning: incorrect type in argument 1 (different address spaces)
i915_gem.c:1199:33: expected void [noderef] <asn:2>*vaddr
i915_gem.c:1199:33: got void *[assigned] vaddr
i915_gem.c:1204:34: warning: incorrect type in argument 1 (different address spaces)
i915_gem.c:1204:34: expected void [noderef] <asn:2>*vaddr
i915_gem.c:1204:34: got void *[assigned] vaddr
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20170901171252.31025-2-ville.syrjala@linux.intel.com
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
radix_tree_for_each_slot() wants an __rcu annotated pointer for the
slot. So let's add the annotation.
Fixes the following sparse warnings:
i915_gem.c:2217:9: warning: incorrect type in assignment (different address spaces)
i915_gem.c:2217:9: expected void **slot
i915_gem.c:2217:9: got void [noderef] <asn:4>**
i915_gem.c:2217:9: warning: incorrect type in assignment (different address spaces)
i915_gem.c:2217:9: expected void **slot
i915_gem.c:2217:9: got void [noderef] <asn:4>**
i915_gem.c:2217:9: warning: incorrect type in argument 1 (different address spaces)
i915_gem.c:2217:9: expected void [noderef] <asn:4>**slot
i915_gem.c:2217:9: got void **slot
i915_gem.c:2217:9: warning: incorrect type in assignment (different address spaces)
i915_gem.c:2217:9: expected void **slot
i915_gem.c:2217:9: got void [noderef] <asn:4>**
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Fixes: 96d7763452 ("drm/i915: Use a radixtree for random access to the object's backing storage")
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20170901171252.31025-1-ville.syrjala@linux.intel.com
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Sometimes we know we are the only user of the bo, but since we take a
protective pin_pages early on, an attempt to change the vmap on the
object is denied because it is busy. i915_gem_object_pin_map() cannot
tell from our single pin_count if the operation is safe. Instead we must
pass that information down from the caller in the manner of
I915_MAP_OVERRIDE.
This issue has existed from the introduction of the mapping, but was
never noticed as the only place where this conflict might happen is for
cached kernel buffers (such as allocated by i915_gem_batch_pool_get()).
Until recently there was only a single user (the cmdparser) so no
conflicts ever occurred. However, we now use it to allocate batches for
different operations (using MAP_WC on !llc for writes) in addition to the
existing shadow batch (using MAP_WB for reads).
We could either keep both mappings cached, or use a different write
mechanism if we detect a MAP_WB already exists (i.e. clflush
afterwards), but as we haven't seen this issue in the wild (it requires
hitting the GPU reloc path in addition to the cmdparser) for simplicity
just allow the mappings to be recreated.
v2: Include the i915_MAP_OVERRIDE bit in the enum so the compiler knows
about all the valid values.
Fixes: 7dd4f6729f ("drm/i915: Async GPU relocation processing")
Testcase: igt/gem_lut_handle # byt, completely by accident
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20170828104631.8606-1-chris@chris-wilson.co.uk
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
(cherry picked from commit a575c67617)
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Sometimes we know we are the only user of the bo, but since we take a
protective pin_pages early on, an attempt to change the vmap on the
object is denied because it is busy. i915_gem_object_pin_map() cannot
tell from our single pin_count if the operation is safe. Instead we must
pass that information down from the caller in the manner of
I915_MAP_OVERRIDE.
This issue has existed from the introduction of the mapping, but was
never noticed as the only place where this conflict might happen is for
cached kernel buffers (such as allocated by i915_gem_batch_pool_get()).
Until recently there was only a single user (the cmdparser) so no
conflicts ever occurred. However, we now use it to allocate batches for
different operations (using MAP_WC on !llc for writes) in addition to the
existing shadow batch (using MAP_WB for reads).
We could either keep both mappings cached, or use a different write
mechanism if we detect a MAP_WB already exists (i.e. clflush
afterwards), but as we haven't seen this issue in the wild (it requires
hitting the GPU reloc path in addition to the cmdparser) for simplicity
just allow the mappings to be recreated.
v2: Include the i915_MAP_OVERRIDE bit in the enum so the compiler knows
about all the valid values.
Fixes: 7dd4f6729f ("drm/i915: Async GPU relocation processing")
Testcase: igt/gem_lut_handle # byt, completely by accident
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20170828104631.8606-1-chris@chris-wilson.co.uk
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
