linux/drivers/gpu/drm/radeon/radeon_mn.c
Michal Hocko 2267c2999b drm/radeon: make radeon_mn_get wait for mmap_sem killable
radeon_mn_get which is called during ioct path relies on mmap_sem for
write.  If the waiting task gets killed by the oom killer it would block
oom_reaper from asynchronous address space reclaim and reduce the
chances of timely OOM resolving.  Wait for the lock in the killable mode
and return with EINTR if the task got killed while waiting.

Signed-off-by: Michal Hocko <mhocko@suse.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Reviewed-by: Christian König <christian.koenig@amd.com>
Cc: Alex Deucher <alexander.deucher@amd.com>
Cc: David Airlie <airlied@linux.ie>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-05-23 17:04:14 -07:00

325 lines
7.9 KiB
C

/*
* Copyright 2014 Advanced Micro Devices, Inc.
* All Rights Reserved.
*
* Permission is hereby granted, free of charge, to any person obtaining a
* copy of this software and associated documentation files (the
* "Software"), to deal in the Software without restriction, including
* without limitation the rights to use, copy, modify, merge, publish,
* distribute, sub license, and/or sell copies of the Software, and to
* permit persons to whom the Software is furnished to do so, subject to
* the following conditions:
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL
* THE COPYRIGHT HOLDERS, AUTHORS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM,
* DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
* OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
* USE OR OTHER DEALINGS IN THE SOFTWARE.
*
* The above copyright notice and this permission notice (including the
* next paragraph) shall be included in all copies or substantial portions
* of the Software.
*
*/
/*
* Authors:
* Christian König <christian.koenig@amd.com>
*/
#include <linux/firmware.h>
#include <linux/module.h>
#include <linux/mmu_notifier.h>
#include <drm/drmP.h>
#include <drm/drm.h>
#include "radeon.h"
struct radeon_mn {
/* constant after initialisation */
struct radeon_device *rdev;
struct mm_struct *mm;
struct mmu_notifier mn;
/* only used on destruction */
struct work_struct work;
/* protected by rdev->mn_lock */
struct hlist_node node;
/* objects protected by lock */
struct mutex lock;
struct rb_root objects;
};
struct radeon_mn_node {
struct interval_tree_node it;
struct list_head bos;
};
/**
* radeon_mn_destroy - destroy the rmn
*
* @work: previously sheduled work item
*
* Lazy destroys the notifier from a work item
*/
static void radeon_mn_destroy(struct work_struct *work)
{
struct radeon_mn *rmn = container_of(work, struct radeon_mn, work);
struct radeon_device *rdev = rmn->rdev;
struct radeon_mn_node *node, *next_node;
struct radeon_bo *bo, *next_bo;
mutex_lock(&rdev->mn_lock);
mutex_lock(&rmn->lock);
hash_del(&rmn->node);
rbtree_postorder_for_each_entry_safe(node, next_node, &rmn->objects,
it.rb) {
interval_tree_remove(&node->it, &rmn->objects);
list_for_each_entry_safe(bo, next_bo, &node->bos, mn_list) {
bo->mn = NULL;
list_del_init(&bo->mn_list);
}
kfree(node);
}
mutex_unlock(&rmn->lock);
mutex_unlock(&rdev->mn_lock);
mmu_notifier_unregister(&rmn->mn, rmn->mm);
kfree(rmn);
}
/**
* radeon_mn_release - callback to notify about mm destruction
*
* @mn: our notifier
* @mn: the mm this callback is about
*
* Shedule a work item to lazy destroy our notifier.
*/
static void radeon_mn_release(struct mmu_notifier *mn,
struct mm_struct *mm)
{
struct radeon_mn *rmn = container_of(mn, struct radeon_mn, mn);
INIT_WORK(&rmn->work, radeon_mn_destroy);
schedule_work(&rmn->work);
}
/**
* radeon_mn_invalidate_range_start - callback to notify about mm change
*
* @mn: our notifier
* @mn: the mm this callback is about
* @start: start of updated range
* @end: end of updated range
*
* We block for all BOs between start and end to be idle and
* unmap them by move them into system domain again.
*/
static void radeon_mn_invalidate_range_start(struct mmu_notifier *mn,
struct mm_struct *mm,
unsigned long start,
unsigned long end)
{
struct radeon_mn *rmn = container_of(mn, struct radeon_mn, mn);
struct interval_tree_node *it;
/* notification is exclusive, but interval is inclusive */
end -= 1;
mutex_lock(&rmn->lock);
it = interval_tree_iter_first(&rmn->objects, start, end);
while (it) {
struct radeon_mn_node *node;
struct radeon_bo *bo;
long r;
node = container_of(it, struct radeon_mn_node, it);
it = interval_tree_iter_next(it, start, end);
list_for_each_entry(bo, &node->bos, mn_list) {
if (!bo->tbo.ttm || bo->tbo.ttm->state != tt_bound)
continue;
r = radeon_bo_reserve(bo, true);
if (r) {
DRM_ERROR("(%ld) failed to reserve user bo\n", r);
continue;
}
r = reservation_object_wait_timeout_rcu(bo->tbo.resv,
true, false, MAX_SCHEDULE_TIMEOUT);
if (r <= 0)
DRM_ERROR("(%ld) failed to wait for user bo\n", r);
radeon_ttm_placement_from_domain(bo, RADEON_GEM_DOMAIN_CPU);
r = ttm_bo_validate(&bo->tbo, &bo->placement, false, false);
if (r)
DRM_ERROR("(%ld) failed to validate user bo\n", r);
radeon_bo_unreserve(bo);
}
}
mutex_unlock(&rmn->lock);
}
static const struct mmu_notifier_ops radeon_mn_ops = {
.release = radeon_mn_release,
.invalidate_range_start = radeon_mn_invalidate_range_start,
};
/**
* radeon_mn_get - create notifier context
*
* @rdev: radeon device pointer
*
* Creates a notifier context for current->mm.
*/
static struct radeon_mn *radeon_mn_get(struct radeon_device *rdev)
{
struct mm_struct *mm = current->mm;
struct radeon_mn *rmn;
int r;
if (down_write_killable(&mm->mmap_sem))
return ERR_PTR(-EINTR);
mutex_lock(&rdev->mn_lock);
hash_for_each_possible(rdev->mn_hash, rmn, node, (unsigned long)mm)
if (rmn->mm == mm)
goto release_locks;
rmn = kzalloc(sizeof(*rmn), GFP_KERNEL);
if (!rmn) {
rmn = ERR_PTR(-ENOMEM);
goto release_locks;
}
rmn->rdev = rdev;
rmn->mm = mm;
rmn->mn.ops = &radeon_mn_ops;
mutex_init(&rmn->lock);
rmn->objects = RB_ROOT;
r = __mmu_notifier_register(&rmn->mn, mm);
if (r)
goto free_rmn;
hash_add(rdev->mn_hash, &rmn->node, (unsigned long)mm);
release_locks:
mutex_unlock(&rdev->mn_lock);
up_write(&mm->mmap_sem);
return rmn;
free_rmn:
mutex_unlock(&rdev->mn_lock);
up_write(&mm->mmap_sem);
kfree(rmn);
return ERR_PTR(r);
}
/**
* radeon_mn_register - register a BO for notifier updates
*
* @bo: radeon buffer object
* @addr: userptr addr we should monitor
*
* Registers an MMU notifier for the given BO at the specified address.
* Returns 0 on success, -ERRNO if anything goes wrong.
*/
int radeon_mn_register(struct radeon_bo *bo, unsigned long addr)
{
unsigned long end = addr + radeon_bo_size(bo) - 1;
struct radeon_device *rdev = bo->rdev;
struct radeon_mn *rmn;
struct radeon_mn_node *node = NULL;
struct list_head bos;
struct interval_tree_node *it;
rmn = radeon_mn_get(rdev);
if (IS_ERR(rmn))
return PTR_ERR(rmn);
INIT_LIST_HEAD(&bos);
mutex_lock(&rmn->lock);
while ((it = interval_tree_iter_first(&rmn->objects, addr, end))) {
kfree(node);
node = container_of(it, struct radeon_mn_node, it);
interval_tree_remove(&node->it, &rmn->objects);
addr = min(it->start, addr);
end = max(it->last, end);
list_splice(&node->bos, &bos);
}
if (!node) {
node = kmalloc(sizeof(struct radeon_mn_node), GFP_KERNEL);
if (!node) {
mutex_unlock(&rmn->lock);
return -ENOMEM;
}
}
bo->mn = rmn;
node->it.start = addr;
node->it.last = end;
INIT_LIST_HEAD(&node->bos);
list_splice(&bos, &node->bos);
list_add(&bo->mn_list, &node->bos);
interval_tree_insert(&node->it, &rmn->objects);
mutex_unlock(&rmn->lock);
return 0;
}
/**
* radeon_mn_unregister - unregister a BO for notifier updates
*
* @bo: radeon buffer object
*
* Remove any registration of MMU notifier updates from the buffer object.
*/
void radeon_mn_unregister(struct radeon_bo *bo)
{
struct radeon_device *rdev = bo->rdev;
struct radeon_mn *rmn;
struct list_head *head;
mutex_lock(&rdev->mn_lock);
rmn = bo->mn;
if (rmn == NULL) {
mutex_unlock(&rdev->mn_lock);
return;
}
mutex_lock(&rmn->lock);
/* save the next list entry for later */
head = bo->mn_list.next;
bo->mn = NULL;
list_del(&bo->mn_list);
if (list_empty(head)) {
struct radeon_mn_node *node;
node = container_of(head, struct radeon_mn_node, bos);
interval_tree_remove(&node->it, &rmn->objects);
kfree(node);
}
mutex_unlock(&rmn->lock);
mutex_unlock(&rdev->mn_lock);
}