mirrors/linux
1
0
Fork 1
mirror of https://github.com/torvalds/linux.git synced 2025-11-03 10:10:33 +02:00
Code Issues Projects Releases Packages Wiki Activity Actions

drm/amdgpu: revert to old status lock handling v3

Browse source 
It turned out that protecting the status of each bo_va with a
spinlock was just hiding problems instead of solving them.

Revert the whole approach, add a separate stats_lock and lockdep
assertions that the correct reservation lock is held all over the place.

This not only allows for better checks if a state transition is properly
protected by a lock, but also switching back to using list macros to
iterate over the state of lists protected by the dma_resv lock of the
root PD.

v2: re-add missing check
v3: split into two patches

Signed-off-by: Christian König <christian.koenig@amd.com>
Acked-by: Sunil Khatri <sunil.khatri@amd.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
This commit is contained in:
Christian König 2025-08-27 11:45:45 +02:00 committed by Alex Deucher
parent 0aa09d8a6c
commit 59e4405e9e
4 changed files with 93 additions and 102 deletions
repo.diff.show_diff_stats Download patch file Download diff file Expand all files Collapse all files

8
drivers/gpu/drm/amd/amdgpu/amdgpu_userq.c
View file

@ -724,12 +724,12 @@ amdgpu_userq_bo_validate(struct amdgpu_device *adev, struct drm_exec *exec,
struct amdgpu_bo *bo;
int ret;
spin_lock(&vm->status_lock);
spin_lock(&vm->invalidated_lock);
while (!list_empty(&vm->invalidated)) {
bo_va = list_first_entry(&vm->invalidated,
struct amdgpu_bo_va,
base.vm_status);
spin_unlock(&vm->status_lock);
spin_unlock(&vm->invalidated_lock);
bo = bo_va->base.bo;
ret = drm_exec_prepare_obj(exec, &bo->tbo.base, 2);
@ -746,9 +746,9 @@ amdgpu_userq_bo_validate(struct amdgpu_device *adev, struct drm_exec *exec,
if (ret)
return ret;
spin_lock(&vm->status_lock);
spin_lock(&vm->invalidated_lock);
}
spin_unlock(&vm->status_lock);
spin_unlock(&vm->invalidated_lock);
return 0;
}

168
drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c
View file

@ -127,6 +127,17 @@ struct amdgpu_vm_tlb_seq_struct {
struct dma_fence_cb cb;
};
/**
* amdgpu_vm_assert_locked - check if VM is correctly locked
* @vm: the VM which schould be tested
*
* Asserts that the VM root PD is locked.
*/
static void amdgpu_vm_assert_locked(struct amdgpu_vm *vm)
{
dma_resv_assert_held(vm->root.bo->tbo.base.resv);
}
/**
* amdgpu_vm_set_pasid - manage pasid and vm ptr mapping
*
@ -143,6 +154,8 @@ int amdgpu_vm_set_pasid(struct amdgpu_device *adev, struct amdgpu_vm *vm,
{
int r;
amdgpu_vm_assert_locked(vm);
if (vm->pasid == pasid)
return 0;
@ -181,12 +194,11 @@ static void amdgpu_vm_bo_evicted(struct amdgpu_vm_bo_base *vm_bo)
struct amdgpu_bo *bo = vm_bo->bo;
vm_bo->moved = true;
spin_lock(&vm_bo->vm->status_lock);
amdgpu_vm_assert_locked(vm);
if (bo->tbo.type == ttm_bo_type_kernel)
list_move(&vm_bo->vm_status, &vm->evicted);
else
list_move_tail(&vm_bo->vm_status, &vm->evicted);
spin_unlock(&vm_bo->vm->status_lock);
}
/**
* amdgpu_vm_bo_moved - vm_bo is moved
@ -198,9 +210,8 @@ static void amdgpu_vm_bo_evicted(struct amdgpu_vm_bo_base *vm_bo)
*/
static void amdgpu_vm_bo_moved(struct amdgpu_vm_bo_base *vm_bo)
{
spin_lock(&vm_bo->vm->status_lock);
amdgpu_vm_assert_locked(vm_bo->vm);
list_move(&vm_bo->vm_status, &vm_bo->vm->moved);
spin_unlock(&vm_bo->vm->status_lock);
}
/**
@ -213,9 +224,8 @@ static void amdgpu_vm_bo_moved(struct amdgpu_vm_bo_base *vm_bo)
*/
static void amdgpu_vm_bo_idle(struct amdgpu_vm_bo_base *vm_bo)
{
spin_lock(&vm_bo->vm->status_lock);
amdgpu_vm_assert_locked(vm_bo->vm);
list_move(&vm_bo->vm_status, &vm_bo->vm->idle);
spin_unlock(&vm_bo->vm->status_lock);
vm_bo->moved = false;
}
@ -229,9 +239,9 @@ static void amdgpu_vm_bo_idle(struct amdgpu_vm_bo_base *vm_bo)
*/
static void amdgpu_vm_bo_invalidated(struct amdgpu_vm_bo_base *vm_bo)
{
spin_lock(&vm_bo->vm->status_lock);
spin_lock(&vm_bo->vm->invalidated_lock);
list_move(&vm_bo->vm_status, &vm_bo->vm->invalidated);
spin_unlock(&vm_bo->vm->status_lock);
spin_unlock(&vm_bo->vm->invalidated_lock);
}
/**
@ -244,10 +254,9 @@ static void amdgpu_vm_bo_invalidated(struct amdgpu_vm_bo_base *vm_bo)
*/
static void amdgpu_vm_bo_evicted_user(struct amdgpu_vm_bo_base *vm_bo)
{
amdgpu_vm_assert_locked(vm_bo->vm);
vm_bo->moved = true;
spin_lock(&vm_bo->vm->status_lock);
list_move(&vm_bo->vm_status, &vm_bo->vm->evicted_user);
spin_unlock(&vm_bo->vm->status_lock);
}
/**
@ -260,13 +269,11 @@ static void amdgpu_vm_bo_evicted_user(struct amdgpu_vm_bo_base *vm_bo)
*/
static void amdgpu_vm_bo_relocated(struct amdgpu_vm_bo_base *vm_bo)
{
if (vm_bo->bo->parent) {
spin_lock(&vm_bo->vm->status_lock);
amdgpu_vm_assert_locked(vm_bo->vm);
if (vm_bo->bo->parent)
list_move(&vm_bo->vm_status, &vm_bo->vm->relocated);
spin_unlock(&vm_bo->vm->status_lock);
} else {
else
amdgpu_vm_bo_idle(vm_bo);
}
}
/**
@ -279,9 +286,8 @@ static void amdgpu_vm_bo_relocated(struct amdgpu_vm_bo_base *vm_bo)
*/
static void amdgpu_vm_bo_done(struct amdgpu_vm_bo_base *vm_bo)
{
spin_lock(&vm_bo->vm->status_lock);
amdgpu_vm_assert_locked(vm_bo->vm);
list_move(&vm_bo->vm_status, &vm_bo->vm->done);
spin_unlock(&vm_bo->vm->status_lock);
}
/**
@ -295,10 +301,13 @@ static void amdgpu_vm_bo_reset_state_machine(struct amdgpu_vm *vm)
{
struct amdgpu_vm_bo_base *vm_bo, *tmp;
spin_lock(&vm->status_lock);
spin_lock(&vm->invalidated_lock);
list_splice_init(&vm->done, &vm->invalidated);
list_for_each_entry(vm_bo, &vm->invalidated, vm_status)
vm_bo->moved = true;
spin_unlock(&vm->invalidated_lock);
amdgpu_vm_assert_locked(vm_bo->vm);
list_for_each_entry_safe(vm_bo, tmp, &vm->idle, vm_status) {
struct amdgpu_bo *bo = vm_bo->bo;
@ -308,14 +317,13 @@ static void amdgpu_vm_bo_reset_state_machine(struct amdgpu_vm *vm)
else if (bo->parent)
list_move(&vm_bo->vm_status, &vm_bo->vm->relocated);
}
spin_unlock(&vm->status_lock);
}
/**
* amdgpu_vm_update_shared - helper to update shared memory stat
* @base: base structure for tracking BO usage in a VM
*
* Takes the vm status_lock and updates the shared memory stat. If the basic
* Takes the vm stats_lock and updates the shared memory stat. If the basic
* stat changed (e.g. buffer was moved) amdgpu_vm_update_stats need to be called
* as well.
*/
@ -327,7 +335,8 @@ static void amdgpu_vm_update_shared(struct amdgpu_vm_bo_base *base)
uint32_t bo_memtype = amdgpu_bo_mem_stats_placement(bo);
bool shared;
spin_lock(&vm->status_lock);
dma_resv_assert_held(bo->tbo.base.resv);
spin_lock(&vm->stats_lock);
shared = drm_gem_object_is_shared_for_memory_stats(&bo->tbo.base);
if (base->shared != shared) {
base->shared = shared;
@ -339,7 +348,7 @@ static void amdgpu_vm_update_shared(struct amdgpu_vm_bo_base *base)
vm->stats[bo_memtype].drm.private += size;
}
}
spin_unlock(&vm->status_lock);
spin_unlock(&vm->stats_lock);
}
/**
@ -364,11 +373,11 @@ void amdgpu_vm_bo_update_shared(struct amdgpu_bo *bo)
* be bo->tbo.resource
* @sign: if we should add (+1) or subtract (-1) from the stat
*
* Caller need to have the vm status_lock held. Useful for when multiple update
* Caller need to have the vm stats_lock held. Useful for when multiple update
* need to happen at the same time.
*/
static void amdgpu_vm_update_stats_locked(struct amdgpu_vm_bo_base *base,
struct ttm_resource *res, int sign)
struct ttm_resource *res, int sign)
{
struct amdgpu_vm *vm = base->vm;
struct amdgpu_bo *bo = base->bo;
@ -392,7 +401,8 @@ static void amdgpu_vm_update_stats_locked(struct amdgpu_vm_bo_base *base,
*/
if (bo->flags & AMDGPU_GEM_CREATE_DISCARDABLE)
vm->stats[res_memtype].drm.purgeable += size;
if (!(bo->preferred_domains & amdgpu_mem_type_to_domain(res_memtype)))
if (!(bo->preferred_domains &
amdgpu_mem_type_to_domain(res_memtype)))
vm->stats[bo_memtype].evicted += size;
}
}
@ -411,9 +421,9 @@ void amdgpu_vm_update_stats(struct amdgpu_vm_bo_base *base,
{
struct amdgpu_vm *vm = base->vm;
spin_lock(&vm->status_lock);
spin_lock(&vm->stats_lock);
amdgpu_vm_update_stats_locked(base, res, sign);
spin_unlock(&vm->status_lock);
spin_unlock(&vm->stats_lock);
}
/**
@ -439,10 +449,10 @@ void amdgpu_vm_bo_base_init(struct amdgpu_vm_bo_base *base,
base->next = bo->vm_bo;
bo->vm_bo = base;
spin_lock(&vm->status_lock);
spin_lock(&vm->stats_lock);
base->shared = drm_gem_object_is_shared_for_memory_stats(&bo->tbo.base);
amdgpu_vm_update_stats_locked(base, bo->tbo.resource, +1);
spin_unlock(&vm->status_lock);
spin_unlock(&vm->stats_lock);
if (!amdgpu_vm_is_bo_always_valid(vm, bo))
return;
@ -501,10 +511,10 @@ int amdgpu_vm_lock_done_list(struct amdgpu_vm *vm, struct drm_exec *exec,
int ret;
/* We can only trust prev->next while holding the lock */
spin_lock(&vm->status_lock);
spin_lock(&vm->invalidated_lock);
while (!list_is_head(prev->next, &vm->done)) {
bo_va = list_entry(prev->next, typeof(*bo_va), base.vm_status);
spin_unlock(&vm->status_lock);
spin_unlock(&vm->invalidated_lock);
bo = bo_va->base.bo;
if (bo) {
@ -512,10 +522,10 @@ int amdgpu_vm_lock_done_list(struct amdgpu_vm *vm, struct drm_exec *exec,
if (unlikely(ret))
return ret;
}
spin_lock(&vm->status_lock);
spin_lock(&vm->invalidated_lock);
prev = prev->next;
}
spin_unlock(&vm->status_lock);
spin_unlock(&vm->invalidated_lock);
return 0;
}
@ -611,7 +621,7 @@ int amdgpu_vm_validate(struct amdgpu_device *adev, struct amdgpu_vm *vm,
void *param)
{
uint64_t new_vm_generation = amdgpu_vm_generation(adev, vm);
struct amdgpu_vm_bo_base *bo_base;
struct amdgpu_vm_bo_base *bo_base, *tmp;
struct amdgpu_bo *bo;
int r;
@ -624,13 +634,7 @@ int amdgpu_vm_validate(struct amdgpu_device *adev, struct amdgpu_vm *vm,
return r;
}
spin_lock(&vm->status_lock);
while (!list_empty(&vm->evicted)) {
bo_base = list_first_entry(&vm->evicted,
struct amdgpu_vm_bo_base,
vm_status);
spin_unlock(&vm->status_lock);
list_for_each_entry_safe(bo_base, tmp, &vm->evicted, vm_status) {
bo = bo_base->bo;
r = validate(param, bo);
@ -643,26 +647,21 @@ int amdgpu_vm_validate(struct amdgpu_device *adev, struct amdgpu_vm *vm,
vm->update_funcs->map_table(to_amdgpu_bo_vm(bo));
amdgpu_vm_bo_relocated(bo_base);
}
spin_lock(&vm->status_lock);
}
while (ticket && !list_empty(&vm->evicted_user)) {
bo_base = list_first_entry(&vm->evicted_user,
struct amdgpu_vm_bo_base,
vm_status);
spin_unlock(&vm->status_lock);
bo = bo_base->bo;
dma_resv_assert_held(bo->tbo.base.resv);
if (ticket) {
list_for_each_entry_safe(bo_base, tmp, &vm->evicted_user,
vm_status) {
bo = bo_base->bo;
dma_resv_assert_held(bo->tbo.base.resv);
r = validate(param, bo);
if (r)
return r;
r = validate(param, bo);
if (r)
return r;
amdgpu_vm_bo_invalidated(bo_base);
spin_lock(&vm->status_lock);
amdgpu_vm_bo_invalidated(bo_base);
}
}
spin_unlock(&vm->status_lock);
amdgpu_vm_eviction_lock(vm);
vm->evicting = false;
@ -685,13 +684,13 @@ bool amdgpu_vm_ready(struct amdgpu_vm *vm)
{
bool ret;
amdgpu_vm_assert_locked(vm);
amdgpu_vm_eviction_lock(vm);
ret = !vm->evicting;
amdgpu_vm_eviction_unlock(vm);
spin_lock(&vm->status_lock);
ret &= list_empty(&vm->evicted);
spin_unlock(&vm->status_lock);
spin_lock(&vm->immediate.lock);
ret &= !vm->immediate.stopped;
@ -982,16 +981,13 @@ int amdgpu_vm_update_pdes(struct amdgpu_device *adev,
struct amdgpu_vm *vm, bool immediate)
{
struct amdgpu_vm_update_params params;
struct amdgpu_vm_bo_base *entry;
struct amdgpu_vm_bo_base *entry, *tmp;
bool flush_tlb_needed = false;
LIST_HEAD(relocated);
int r, idx;
spin_lock(&vm->status_lock);
list_splice_init(&vm->relocated, &relocated);
spin_unlock(&vm->status_lock);
amdgpu_vm_assert_locked(vm);
if (list_empty(&relocated))
if (list_empty(&vm->relocated))
return 0;
if (!drm_dev_enter(adev_to_drm(adev), &idx))
@ -1006,7 +1002,7 @@ int amdgpu_vm_update_pdes(struct amdgpu_device *adev,
if (r)
goto error;
list_for_each_entry(entry, &relocated, vm_status) {
list_for_each_entry(entry, &vm->relocated, vm_status) {
/* vm_flush_needed after updating moved PDEs */
flush_tlb_needed |= entry->moved;
@ -1022,9 +1018,7 @@ int amdgpu_vm_update_pdes(struct amdgpu_device *adev,
if (flush_tlb_needed)
atomic64_inc(&vm->tlb_seq);
while (!list_empty(&relocated)) {
entry = list_first_entry(&relocated, struct amdgpu_vm_bo_base,
vm_status);
list_for_each_entry_safe(entry, tmp, &vm->relocated, vm_status) {
amdgpu_vm_bo_idle(entry);
}
@ -1250,9 +1244,9 @@ int amdgpu_vm_update_range(struct amdgpu_device *adev, struct amdgpu_vm *vm,
void amdgpu_vm_get_memory(struct amdgpu_vm *vm,
struct amdgpu_mem_stats stats[__AMDGPU_PL_NUM])
{
spin_lock(&vm->status_lock);
spin_lock(&vm->stats_lock);
memcpy(stats, vm->stats, sizeof(*stats) * __AMDGPU_PL_NUM);
spin_unlock(&vm->status_lock);
spin_unlock(&vm->stats_lock);
}
/**
@ -1619,29 +1613,24 @@ int amdgpu_vm_handle_moved(struct amdgpu_device *adev,
struct amdgpu_vm *vm,
struct ww_acquire_ctx *ticket)
{
struct amdgpu_bo_va *bo_va;
struct amdgpu_bo_va *bo_va, *tmp;
struct dma_resv *resv;
bool clear, unlock;
int r;
spin_lock(&vm->status_lock);
while (!list_empty(&vm->moved)) {
bo_va = list_first_entry(&vm->moved, struct amdgpu_bo_va,
base.vm_status);
spin_unlock(&vm->status_lock);
list_for_each_entry_safe(bo_va, tmp, &vm->moved, base.vm_status) {
/* Per VM BOs never need to bo cleared in the page tables */
r = amdgpu_vm_bo_update(adev, bo_va, false);
if (r)
return r;
spin_lock(&vm->status_lock);
}
spin_lock(&vm->invalidated_lock);
while (!list_empty(&vm->invalidated)) {
bo_va = list_first_entry(&vm->invalidated, struct amdgpu_bo_va,
base.vm_status);
resv = bo_va->base.bo->tbo.base.resv;
spin_unlock(&vm->status_lock);
spin_unlock(&vm->invalidated_lock);
/* Try to reserve the BO to avoid clearing its ptes */
if (!adev->debug_vm && dma_resv_trylock(resv)) {
@ -1673,9 +1662,9 @@ int amdgpu_vm_handle_moved(struct amdgpu_device *adev,
bo_va->base.bo->tbo.resource->mem_type == TTM_PL_SYSTEM))
amdgpu_vm_bo_evicted_user(&bo_va->base);
spin_lock(&vm->status_lock);
spin_lock(&vm->invalidated_lock);
}
spin_unlock(&vm->status_lock);
spin_unlock(&vm->invalidated_lock);
return 0;
}
@ -2204,9 +2193,9 @@ void amdgpu_vm_bo_del(struct amdgpu_device *adev,
}
}
spin_lock(&vm->status_lock);
spin_lock(&vm->invalidated_lock);
list_del(&bo_va->base.vm_status);
spin_unlock(&vm->status_lock);
spin_unlock(&vm->invalidated_lock);
list_for_each_entry_safe(mapping, next, &bo_va->valids, list) {
list_del(&mapping->list);
@ -2314,10 +2303,10 @@ void amdgpu_vm_bo_move(struct amdgpu_bo *bo, struct ttm_resource *new_mem,
for (bo_base = bo->vm_bo; bo_base; bo_base = bo_base->next) {
struct amdgpu_vm *vm = bo_base->vm;
spin_lock(&vm->status_lock);
spin_lock(&vm->stats_lock);
amdgpu_vm_update_stats_locked(bo_base, bo->tbo.resource, -1);
amdgpu_vm_update_stats_locked(bo_base, new_mem, +1);
spin_unlock(&vm->status_lock);
spin_unlock(&vm->stats_lock);
}
amdgpu_vm_bo_invalidate(bo, evicted);
@ -2584,11 +2573,12 @@ int amdgpu_vm_init(struct amdgpu_device *adev, struct amdgpu_vm *vm,
INIT_LIST_HEAD(&vm->relocated);
INIT_LIST_HEAD(&vm->moved);
INIT_LIST_HEAD(&vm->idle);
spin_lock_init(&vm->invalidated_lock);
INIT_LIST_HEAD(&vm->invalidated);
spin_lock_init(&vm->status_lock);
INIT_LIST_HEAD(&vm->freed);
INIT_LIST_HEAD(&vm->done);
INIT_KFIFO(vm->faults);
spin_lock_init(&vm->stats_lock);
r = amdgpu_vm_init_entities(adev, vm);
if (r)
@ -3053,7 +3043,8 @@ void amdgpu_debugfs_vm_bo_info(struct amdgpu_vm *vm, struct seq_file *m)
unsigned int total_done_objs = 0;
unsigned int id = 0;
spin_lock(&vm->status_lock);
amdgpu_vm_assert_locked(vm);
seq_puts(m, "\tIdle BOs:\n");
list_for_each_entry_safe(bo_va, tmp, &vm->idle, base.vm_status) {
if (!bo_va->base.bo)
@ -3091,11 +3082,13 @@ void amdgpu_debugfs_vm_bo_info(struct amdgpu_vm *vm, struct seq_file *m)
id = 0;
seq_puts(m, "\tInvalidated BOs:\n");
spin_lock(&vm->invalidated_lock);
list_for_each_entry_safe(bo_va, tmp, &vm->invalidated, base.vm_status) {
if (!bo_va->base.bo)
continue;
total_invalidated += amdgpu_bo_print_info(id++, bo_va->base.bo, m);
}
spin_unlock(&vm->invalidated_lock);
total_invalidated_objs = id;
id = 0;
@ -3105,7 +3098,6 @@ void amdgpu_debugfs_vm_bo_info(struct amdgpu_vm *vm, struct seq_file *m)
continue;
total_done += amdgpu_bo_print_info(id++, bo_va->base.bo, m);
}
spin_unlock(&vm->status_lock);
total_done_objs = id;
seq_printf(m, "\tTotal idle size: %12lld\tobjs:\t%d\n", total_idle,

15
drivers/gpu/drm/amd/amdgpu/amdgpu_vm.h
View file

@ -203,11 +203,11 @@ struct amdgpu_vm_bo_base {
/* protected by bo being reserved */
struct amdgpu_vm_bo_base *next;
/* protected by vm status_lock */
/* protected by vm reservation and invalidated_lock */
struct list_head vm_status;
/* if the bo is counted as shared in mem stats
* protected by vm status_lock */
* protected by vm BO being reserved */
bool shared;
/* protected by the BO being reserved */
@ -343,10 +343,8 @@ struct amdgpu_vm {
bool evicting;
unsigned int saved_flags;
/* Lock to protect vm_bo add/del/move on all lists of vm */
spinlock_t status_lock;
/* Memory statistics for this vm, protected by status_lock */
/* Memory statistics for this vm, protected by stats_lock */
spinlock_t stats_lock;
struct amdgpu_mem_stats stats[__AMDGPU_PL_NUM];
/*
@ -354,6 +352,8 @@ struct amdgpu_vm {
* PDs, PTs or per VM BOs. The state transits are:
*
* evicted -> relocated (PDs, PTs) or moved (per VM BOs) -> idle
*
* Lists are protected by the root PD dma_resv lock.
*/
/* Per-VM and PT BOs who needs a validation */
@ -374,7 +374,10 @@ struct amdgpu_vm {
* state transits are:
*
* evicted_user or invalidated -> done
*
* Lists are protected by the invalidated_lock.
*/
spinlock_t invalidated_lock;
/* BOs for user mode queues that need a validation */
struct list_head evicted_user;

4
drivers/gpu/drm/amd/amdgpu/amdgpu_vm_pt.c
View file

@ -541,9 +541,7 @@ static void amdgpu_vm_pt_free(struct amdgpu_vm_bo_base *entry)
entry->bo->vm_bo = NULL;
ttm_bo_set_bulk_move(&entry->bo->tbo, NULL);
spin_lock(&entry->vm->status_lock);
list_del(&entry->vm_status);
spin_unlock(&entry->vm->status_lock);
amdgpu_bo_unref(&entry->bo);
}
@ -587,7 +585,6 @@ static void amdgpu_vm_pt_add_list(struct amdgpu_vm_update_params *params,
struct amdgpu_vm_pt_cursor seek;
struct amdgpu_vm_bo_base *entry;
spin_lock(&params->vm->status_lock);
for_each_amdgpu_vm_pt_dfs_safe(params->adev, params->vm, cursor, seek, entry) {
if (entry && entry->bo)
list_move(&entry->vm_status, &params->tlb_flush_waitlist);
@ -595,7 +592,6 @@ static void amdgpu_vm_pt_add_list(struct amdgpu_vm_update_params *params,
/* enter start node now */
list_move(&cursor->entry->vm_status, &params->tlb_flush_waitlist);
spin_unlock(&params->vm->status_lock);
}
/**