[PATCH 1/3] drm/amdgpu: use HMM mirror callback to replace mmu notifier v6

Yang, Philip
2019-01-10T17:02:45Z

Replace our MMU notifier with hmm_mirror_ops.sync_cpu_device_pagetables
callback. Enable CONFIG_HMM and CONFIG_HMM_MIRROR as a dependency in
DRM_AMDGPU_USERPTR Kconfig.

It supports both KFD userptr and gfx userptr paths.

The depdent HMM patchset from Jérôme Glisse are all merged into 4.20.0
kernel now.

Change-Id: Ie62c3c5e3c5b8521ab3b438d1eff2aa2a003835e
Signed-off-by: Philip Yang <Philip.Yang@amd.com>
---
drivers/gpu/drm/amd/amdgpu/Kconfig | 6 +-
drivers/gpu/drm/amd/amdgpu/Makefile | 2 +-
drivers/gpu/drm/amd/amdgpu/amdgpu_mn.c | 122 ++++++++++---------------
drivers/gpu/drm/amd/amdgpu/amdgpu_mn.h | 2 +-
4 files changed, 55 insertions(+), 77 deletions(-)

diff --git a/drivers/gpu/drm/amd/amdgpu/Kconfig b/drivers/gpu/drm/amd/amdgpu/Kconfig
index 9221e5489069..960a63355705 100644
--- a/drivers/gpu/drm/amd/amdgpu/Kconfig
+++ b/drivers/gpu/drm/amd/amdgpu/Kconfig
@@ -26,10 +26,10 @@ config DRM_AMDGPU_CIK
config DRM_AMDGPU_USERPTR
bool "Always enable userptr write support"
depends on DRM_AMDGPU
- select MMU_NOTIFIER
+ select HMM_MIRROR
help
- This option selects CONFIG_MMU_NOTIFIER if it isn't already
- selected to enabled full userptr support.
+ This option selects CONFIG_HMM and CONFIG_HMM_MIRROR if it
+ isn't already selected to enabled full userptr support.

config DRM_AMDGPU_GART_DEBUGFS
bool "Allow GART access through debugfs"
diff --git a/drivers/gpu/drm/amd/amdgpu/Makefile b/drivers/gpu/drm/amd/amdgpu/Makefile
index f76bcb9c45e4..675efc850ff4 100644
--- a/drivers/gpu/drm/amd/amdgpu/Makefile
+++ b/drivers/gpu/drm/amd/amdgpu/Makefile
@@ -172,7 +172,7 @@ endif
amdgpu-$(CONFIG_COMPAT) += amdgpu_ioc32.o
amdgpu-$(CONFIG_VGA_SWITCHEROO) += amdgpu_atpx_handler.o
amdgpu-$(CONFIG_ACPI) += amdgpu_acpi.o
-amdgpu-$(CONFIG_MMU_NOTIFIER) += amdgpu_mn.o
+amdgpu-$(CONFIG_HMM_MIRROR) += amdgpu_mn.o

include $(FULL_AMD_PATH)/powerplay/Makefile

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_mn.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_mn.c
index e55508b39496..5d518d2bb9be 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_mn.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_mn.c
@@ -45,7 +45,7 @@

#include <linux/firmware.h>
#include <linux/module.h>
-#include <linux/mmu_notifier.h>
+#include <linux/hmm.h>
#include <linux/interval_tree.h>
#include <drm/drmP.h>
#include <drm/drm.h>
@@ -58,7 +58,6 @@
*
* @adev: amdgpu device pointer
* @mm: process address space
- * @mn: MMU notifier structure
* @type: type of MMU notifier
* @work: destruction work item
* @node: hash table node to find structure by adev and mn
@@ -66,6 +65,7 @@
* @objects: interval tree containing amdgpu_mn_nodes
* @read_lock: mutex for recursive locking of @lock
* @recursion: depth of recursion
+ * @mirror: HMM mirror function support
*
* Data for each amdgpu device and process address space.
*/
@@ -73,7 +73,6 @@ struct amdgpu_mn {
/* constant after initialisation */
struct amdgpu_device *adev;
struct mm_struct *mm;
- struct mmu_notifier mn;
enum amdgpu_mn_type type;

/* only used on destruction */
@@ -87,6 +86,9 @@ struct amdgpu_mn {
struct rb_root_cached objects;
struct mutex read_lock;
atomic_t recursion;
+
+ /* HMM mirror */
+ struct hmm_mirror mirror;
};

/**
@@ -103,7 +105,7 @@ struct amdgpu_mn_node {
};

/**
- * amdgpu_mn_destroy - destroy the MMU notifier
+ * amdgpu_mn_destroy - destroy the HMM mirror
*
* @work: previously sheduled work item
*
@@ -129,28 +131,26 @@ static void amdgpu_mn_destroy(struct work_struct *work)
}
up_write(&amn->lock);
mutex_unlock(&adev->mn_lock);
- mmu_notifier_unregister_no_release(&amn->mn, amn->mm);
+
+ hmm_mirror_unregister(&amn->mirror);
kfree(amn);
}

/**
- * amdgpu_mn_release - callback to notify about mm destruction
+ * amdgpu_hmm_mirror_release - callback to notify about mm destruction
*
- * @mn: our notifier
- * @mm: the mm this callback is about
+ * @mirror: the HMM mirror (mm) this callback is about
*
- * Shedule a work item to lazy destroy our notifier.
+ * Shedule a work item to lazy destroy HMM mirror.
*/
-static void amdgpu_mn_release(struct mmu_notifier *mn,
- struct mm_struct *mm)
+static void amdgpu_hmm_mirror_release(struct hmm_mirror *mirror)
{
- struct amdgpu_mn *amn = container_of(mn, struct amdgpu_mn, mn);
+ struct amdgpu_mn *amn = container_of(mirror, struct amdgpu_mn, mirror);

INIT_WORK(&amn->work, amdgpu_mn_destroy);
schedule_work(&amn->work);
}

-
/**
* amdgpu_mn_lock - take the write side lock for this notifier
*
@@ -237,21 +237,19 @@ static void amdgpu_mn_invalidate_node(struct amdgpu_mn_node *node,
/**
* amdgpu_mn_invalidate_range_start_gfx - callback to notify about mm change
*
- * @mn: our notifier
- * @mm: the mm this callback is about
- * @start: start of updated range
- * @end: end of updated range
+ * @mirror: the hmm_mirror (mm) is about to update
+ * @update: the update start, end address
*
* Block for operations on BOs to finish and mark pages as accessed and
* potentially dirty.
*/
-static int amdgpu_mn_invalidate_range_start_gfx(struct mmu_notifier *mn,
- struct mm_struct *mm,
- unsigned long start,
- unsigned long end,
- bool blockable)
+static int amdgpu_mn_sync_pagetables_gfx(struct hmm_mirror *mirror,
+ const struct hmm_update *update)
{
- struct amdgpu_mn *amn = container_of(mn, struct amdgpu_mn, mn);
+ struct amdgpu_mn *amn = container_of(mirror, struct amdgpu_mn, mirror);
+ unsigned long start = update->start;
+ unsigned long end = update->end;
+ bool blockable = update->blockable;
struct interval_tree_node *it;

/* notification is exclusive, but interval is inclusive */
@@ -278,28 +276,28 @@ static int amdgpu_mn_invalidate_range_start_gfx(struct mmu_notifier *mn,
amdgpu_mn_invalidate_node(node, start, end);
}

+ amdgpu_mn_read_unlock(amn);
+
return 0;
}

/**
* amdgpu_mn_invalidate_range_start_hsa - callback to notify about mm change
*
- * @mn: our notifier
- * @mm: the mm this callback is about
- * @start: start of updated range
- * @end: end of updated range
+ * @mirror: the hmm_mirror (mm) is about to update
+ * @update: the update start, end address
*
* We temporarily evict all BOs between start and end. This
* necessitates evicting all user-mode queues of the process. The BOs
* are restorted in amdgpu_mn_invalidate_range_end_hsa.
*/
-static int amdgpu_mn_invalidate_range_start_hsa(struct mmu_notifier *mn,
- struct mm_struct *mm,
- unsigned long start,
- unsigned long end,
- bool blockable)
+static int amdgpu_mn_sync_pagetables_hsa(struct hmm_mirror *mirror,
+ const struct hmm_update *update)
{
- struct amdgpu_mn *amn = container_of(mn, struct amdgpu_mn, mn);
+ struct amdgpu_mn *amn = container_of(mirror, struct amdgpu_mn, mirror);
+ unsigned long start = update->start;
+ unsigned long end = update->end;
+ bool blockable = update->blockable;
struct interval_tree_node *it;

/* notification is exclusive, but interval is inclusive */
@@ -326,59 +324,39 @@ static int amdgpu_mn_invalidate_range_start_hsa(struct mmu_notifier *mn,

if (amdgpu_ttm_tt_affect_userptr(bo->tbo.ttm,
start, end))
- amdgpu_amdkfd_evict_userptr(mem, mm);
+ amdgpu_amdkfd_evict_userptr(mem, amn->mm);
}
}

+ amdgpu_mn_read_unlock(amn);
+
return 0;
}

-/**
- * amdgpu_mn_invalidate_range_end - callback to notify about mm change
- *
- * @mn: our notifier
- * @mm: the mm this callback is about
- * @start: start of updated range
- * @end: end of updated range
- *
- * Release the lock again to allow new command submissions.
+/* Low bits of any reasonable mm pointer will be unused due to struct
+ * alignment. Use these bits to make a unique key from the mm pointer
+ * and notifier type.
*/
-static void amdgpu_mn_invalidate_range_end(struct mmu_notifier *mn,
- struct mm_struct *mm,
- unsigned long start,
- unsigned long end)
-{
- struct amdgpu_mn *amn = container_of(mn, struct amdgpu_mn, mn);
-
- amdgpu_mn_read_unlock(amn);
-}
+#define AMDGPU_MN_KEY(mm, type) ((unsigned long)(mm) + (type))

-static const struct mmu_notifier_ops amdgpu_mn_ops[] = {
+static struct hmm_mirror_ops amdgpu_hmm_mirror_ops[] = {
[AMDGPU_MN_TYPE_GFX] = {
- .release = amdgpu_mn_release,
- .invalidate_range_start = amdgpu_mn_invalidate_range_start_gfx,
- .invalidate_range_end = amdgpu_mn_invalidate_range_end,
+ .sync_cpu_device_pagetables = amdgpu_mn_sync_pagetables_gfx,
+ .release = amdgpu_hmm_mirror_release
},
[AMDGPU_MN_TYPE_HSA] = {
- .release = amdgpu_mn_release,
- .invalidate_range_start = amdgpu_mn_invalidate_range_start_hsa,
- .invalidate_range_end = amdgpu_mn_invalidate_range_end,
+ .sync_cpu_device_pagetables = amdgpu_mn_sync_pagetables_hsa,
+ .release = amdgpu_hmm_mirror_release
},
};

-/* Low bits of any reasonable mm pointer will be unused due to struct
- * alignment. Use these bits to make a unique key from the mm pointer
- * and notifier type.
- */
-#define AMDGPU_MN_KEY(mm, type) ((unsigned long)(mm) + (type))
-
/**
- * amdgpu_mn_get - create notifier context
+ * amdgpu_mn_get - create HMM mirror context
*
* @adev: amdgpu device pointer
* @type: type of MMU notifier context
*
- * Creates a notifier context for current->mm.
+ * Creates a HMM mirror context for current->mm.
*/
struct amdgpu_mn *amdgpu_mn_get(struct amdgpu_device *adev,
enum amdgpu_mn_type type)
@@ -408,12 +386,12 @@ struct amdgpu_mn *amdgpu_mn_get(struct amdgpu_device *adev,
amn->mm = mm;
init_rwsem(&amn->lock);
amn->type = type;
- amn->mn.ops = &amdgpu_mn_ops[type];
amn->objects = RB_ROOT_CACHED;
mutex_init(&amn->read_lock);
atomic_set(&amn->recursion, 0);

- r = __mmu_notifier_register(&amn->mn, mm);
+ amn->mirror.ops = &amdgpu_hmm_mirror_ops[type];
+ r = hmm_mirror_register(&amn->mirror, mm);
if (r)
goto free_amn;

@@ -439,7 +417,7 @@ struct amdgpu_mn *amdgpu_mn_get(struct amdgpu_device *adev,
* @bo: amdgpu buffer object
* @addr: userptr addr we should monitor
*
- * Registers an MMU notifier for the given BO at the specified address.
+ * Registers an HMM mirror for the given BO at the specified address.
* Returns 0 on success, -ERRNO if anything goes wrong.
*/
int amdgpu_mn_register(struct amdgpu_bo *bo, unsigned long addr)
@@ -495,11 +473,11 @@ int amdgpu_mn_register(struct amdgpu_bo *bo, unsigned long addr)
}

/**
- * amdgpu_mn_unregister - unregister a BO for notifier updates
+ * amdgpu_mn_unregister - unregister a BO for HMM mirror updates
*
* @bo: amdgpu buffer object
*
- * Remove any registration of MMU notifier updates from the buffer object.
+ * Remove any registration of HMM mirror updates from the buffer object.
*/
void amdgpu_mn_unregister(struct amdgpu_bo *bo)
{
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_mn.h b/drivers/gpu/drm/amd/amdgpu/amdgpu_mn.h
index eb0f432f78fe..0a51fd00021c 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_mn.h
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_mn.h
@@ -34,7 +34,7 @@ enum amdgpu_mn_type {
AMDGPU_MN_TYPE_HSA,
};

-#if defined(CONFIG_MMU_NOTIFIER)
+#if defined(CONFIG_HMM_MIRROR)
void amdgpu_mn_lock(struct amdgpu_mn *mn);
void amdgpu_mn_unlock(struct amdgpu_mn *mn);
struct amdgpu_mn *amdgpu_mn_get(struct amdgpu_device *adev,
--
2.17.1