cgroup resource allocation has to be handled in TTM, so -EAGAIN from
cgroups can be converted into -ENOSPC, and the limitcg can be properly
evicted in ttm code.
When hitting a resource limit through -EAGAIN, the cgroup for which the
limit is hit is also returned. This allows eviction to delete only from
cgroups which are a subgroup of the current cgroup.
The returned CSS is used to determine if eviction is valuable for a
given resource, and allows TTM to only target specific resources to
lower memory usage.
Co-developed-by: Friedrich Vock <friedrich.vock@xxxxxx>
Signed-off-by: Friedrich Vock <friedrich.vock@xxxxxx>
Co-developed-by: Maxime Ripard <mripard@xxxxxxxxxx>
Signed-off-by: Maxime Ripard <mripard@xxxxxxxxxx>
Signed-off-by: Maarten Lankhorst <dev@xxxxxxxxxxxx>
---
drivers/gpu/drm/ttm/tests/ttm_bo_test.c | 18 +++----
.../gpu/drm/ttm/tests/ttm_bo_validate_test.c | 4 +-
drivers/gpu/drm/ttm/tests/ttm_resource_test.c | 2 +-
drivers/gpu/drm/ttm/ttm_bo.c | 54 ++++++++++++++++---
drivers/gpu/drm/ttm/ttm_resource.c | 23 +++++++-
include/drm/ttm/ttm_resource.h | 12 ++++-
6 files changed, 90 insertions(+), 23 deletions(-)
diff --git a/drivers/gpu/drm/ttm/tests/ttm_bo_test.c b/drivers/gpu/drm/ttm/tests/ttm_bo_test.c
index 3139fd9128d84..f8f20d2f61740 100644
--- a/drivers/gpu/drm/ttm/tests/ttm_bo_test.c
+++ b/drivers/gpu/drm/ttm/tests/ttm_bo_test.c
@@ -258,13 +258,13 @@ static void ttm_bo_unreserve_basic(struct kunit *test)
bo = ttm_bo_kunit_init(test, test->priv, BO_SIZE, NULL);
bo->priority = bo_prio;
- err = ttm_resource_alloc(bo, place, &res1);
+ err = ttm_resource_alloc(bo, place, &res1, NULL);
KUNIT_ASSERT_EQ(test, err, 0);
bo->resource = res1;
/* Add a dummy resource to populate LRU */
- ttm_resource_alloc(bo, place, &res2);
+ ttm_resource_alloc(bo, place, &res2, NULL);
dma_resv_lock(bo->base.resv, NULL);
ttm_bo_unreserve(bo);
@@ -300,12 +300,12 @@ static void ttm_bo_unreserve_pinned(struct kunit *test)
dma_resv_lock(bo->base.resv, NULL);
ttm_bo_pin(bo);
- err = ttm_resource_alloc(bo, place, &res1);
+ err = ttm_resource_alloc(bo, place, &res1, NULL);
KUNIT_ASSERT_EQ(test, err, 0);
bo->resource = res1;
/* Add a dummy resource to the pinned list */
- err = ttm_resource_alloc(bo, place, &res2);
+ err = ttm_resource_alloc(bo, place, &res2, NULL);
KUNIT_ASSERT_EQ(test, err, 0);
KUNIT_ASSERT_EQ(test,
list_is_last(&res2->lru.link, &priv->ttm_dev->unevictable), 1);
@@ -355,7 +355,7 @@ static void ttm_bo_unreserve_bulk(struct kunit *test)
ttm_bo_set_bulk_move(bo1, &lru_bulk_move);
dma_resv_unlock(bo1->base.resv);
- err = ttm_resource_alloc(bo1, place, &res1);
+ err = ttm_resource_alloc(bo1, place, &res1, NULL);
KUNIT_ASSERT_EQ(test, err, 0);
bo1->resource = res1;
@@ -363,7 +363,7 @@ static void ttm_bo_unreserve_bulk(struct kunit *test)
ttm_bo_set_bulk_move(bo2, &lru_bulk_move);
dma_resv_unlock(bo2->base.resv);
- err = ttm_resource_alloc(bo2, place, &res2);
+ err = ttm_resource_alloc(bo2, place, &res2, NULL);
KUNIT_ASSERT_EQ(test, err, 0);
bo2->resource = res2;
@@ -401,7 +401,7 @@ static void ttm_bo_put_basic(struct kunit *test)
bo = ttm_bo_kunit_init(test, test->priv, BO_SIZE, NULL);
bo->type = ttm_bo_type_device;
- err = ttm_resource_alloc(bo, place, &res);
+ err = ttm_resource_alloc(bo, place, &res, NULL);
KUNIT_ASSERT_EQ(test, err, 0);
bo->resource = res;
@@ -518,7 +518,7 @@ static void ttm_bo_pin_unpin_resource(struct kunit *test)
bo = ttm_bo_kunit_init(test, test->priv, BO_SIZE, NULL);
- err = ttm_resource_alloc(bo, place, &res);
+ err = ttm_resource_alloc(bo, place, &res, NULL);
KUNIT_ASSERT_EQ(test, err, 0);
bo->resource = res;
@@ -569,7 +569,7 @@ static void ttm_bo_multiple_pin_one_unpin(struct kunit *test)
bo = ttm_bo_kunit_init(test, test->priv, BO_SIZE, NULL);
- err = ttm_resource_alloc(bo, place, &res);
+ err = ttm_resource_alloc(bo, place, &res, NULL);
KUNIT_ASSERT_EQ(test, err, 0);
bo->resource = res;
diff --git a/drivers/gpu/drm/ttm/tests/ttm_bo_validate_test.c b/drivers/gpu/drm/ttm/tests/ttm_bo_validate_test.c
index 1adf18481ea05..3148f5d3dbd66 100644
--- a/drivers/gpu/drm/ttm/tests/ttm_bo_validate_test.c
+++ b/drivers/gpu/drm/ttm/tests/ttm_bo_validate_test.c
@@ -542,7 +542,7 @@ static void ttm_bo_validate_no_placement_signaled(struct kunit *test)
bo->ttm = old_tt;
}
- err = ttm_resource_alloc(bo, place, &bo->resource);
+ err = ttm_resource_alloc(bo, place, &bo->resource, NULL);
KUNIT_EXPECT_EQ(test, err, 0);
KUNIT_ASSERT_EQ(test, man->usage, size);
@@ -603,7 +603,7 @@ static void ttm_bo_validate_no_placement_not_signaled(struct kunit *test)
bo = ttm_bo_kunit_init(test, test->priv, size, NULL);
bo->type = params->bo_type;
- err = ttm_resource_alloc(bo, place, &bo->resource);
+ err = ttm_resource_alloc(bo, place, &bo->resource, NULL);
KUNIT_EXPECT_EQ(test, err, 0);
placement = kunit_kzalloc(test, sizeof(*placement), GFP_KERNEL);
diff --git a/drivers/gpu/drm/ttm/tests/ttm_resource_test.c b/drivers/gpu/drm/ttm/tests/ttm_resource_test.c
index a9f4b81921c3c..e6ea2bd01f07a 100644
--- a/drivers/gpu/drm/ttm/tests/ttm_resource_test.c
+++ b/drivers/gpu/drm/ttm/tests/ttm_resource_test.c
@@ -302,7 +302,7 @@ static void ttm_sys_man_free_basic(struct kunit *test)
res = kunit_kzalloc(test, sizeof(*res), GFP_KERNEL);
KUNIT_ASSERT_NOT_NULL(test, res);
- ttm_resource_alloc(bo, place, &res);
+ ttm_resource_alloc(bo, place, &res, NULL);
man = ttm_manager_type(priv->devs->ttm_dev, mem_type);
man->func->free(man, res);
diff --git a/drivers/gpu/drm/ttm/ttm_bo.c b/drivers/gpu/drm/ttm/ttm_bo.c
index 48c5365efca1c..aab49dee65a76 100644
--- a/drivers/gpu/drm/ttm/ttm_bo.c
+++ b/drivers/gpu/drm/ttm/ttm_bo.c
@@ -42,6 +42,7 @@
#include <linux/file.h>
#include <linux/module.h>
#include <linux/atomic.h>
+#include <linux/cgroup_dmem.h>
#include <linux/dma-resv.h>
#include "ttm_module.h"
@@ -447,7 +448,7 @@ int ttm_bo_evict_first(struct ttm_device *bdev, struct ttm_resource_manager *man
struct ttm_buffer_object *bo;
struct ttm_resource *res;
unsigned int mem_type;
- int ret = 0;
+ int ret;
spin_lock(&bdev->lru_lock);
res = ttm_resource_manager_first(man, &cursor);
@@ -499,6 +500,13 @@ struct ttm_bo_evict_walk {
struct ttm_resource **res;
/** @evicted: Number of successful evictions. */
unsigned long evicted;
+
+ /** @limit_pool: Which pool limit we should test against */
+ struct dmem_cgroup_pool_state *limit_pool;
+ /** @try_low: Whether we should attempt to evict BO's with low watermark threshold */
+ bool try_low;
+ /** @hit_low: If we cannot evict a bo when @try_low is false (first pass) */
+ bool hit_low;
};
static s64 ttm_bo_evict_cb(struct ttm_lru_walk *walk, struct ttm_buffer_object *bo)
@@ -507,6 +515,10 @@ static s64 ttm_bo_evict_cb(struct ttm_lru_walk *walk, struct ttm_buffer_object *
container_of(walk, typeof(*evict_walk), walk);
s64 lret;
+ if (!dmem_cgroup_state_evict_valuable(evict_walk->limit_pool, bo->resource->css,
+ evict_walk->try_low, &evict_walk->hit_low))
+ return 0;
+
if (bo->pin_count || !bo->bdev->funcs->eviction_valuable(bo, evict_walk->place))
return 0;
@@ -524,7 +536,7 @@ static s64 ttm_bo_evict_cb(struct ttm_lru_walk *walk, struct ttm_buffer_object *
evict_walk->evicted++;
if (evict_walk->res)
lret = ttm_resource_alloc(evict_walk->evictor, evict_walk->place,
- evict_walk->res);
+ evict_walk->res, NULL);
if (lret == 0)
return 1;
out:
@@ -545,7 +557,8 @@ static int ttm_bo_evict_alloc(struct ttm_device *bdev,
struct ttm_buffer_object *evictor,
struct ttm_operation_ctx *ctx,
struct ww_acquire_ctx *ticket,
- struct ttm_resource **res)
+ struct ttm_resource **res,
+ struct dmem_cgroup_pool_state *limit_pool)
{
struct ttm_bo_evict_walk evict_walk = {
.walk = {
@@ -556,22 +569,39 @@ static int ttm_bo_evict_alloc(struct ttm_device *bdev,
.place = place,
.evictor = evictor,
.res = res,
+ .limit_pool = limit_pool,
};
s64 lret;
evict_walk.walk.trylock_only = true;
lret = ttm_lru_walk_for_evict(&evict_walk.walk, bdev, man, 1);
+
+ /* One more attempt if we hit low limit? */
+ if (!lret && evict_walk.hit_low) {
+ evict_walk.try_low = true;
+ lret = ttm_lru_walk_for_evict(&evict_walk.walk, bdev, man, 1);
+ }
if (lret || !ticket)
goto out;
+ /* Reset low limit */
+ evict_walk.try_low = evict_walk.hit_low = false;
/* If ticket-locking, repeat while making progress. */
evict_walk.walk.trylock_only = false;
+
+retry:
do {
/* The walk may clear the evict_walk.walk.ticket field */
evict_walk.walk.ticket = ticket;
evict_walk.evicted = 0;
lret = ttm_lru_walk_for_evict(&evict_walk.walk, bdev, man, 1);
} while (!lret && evict_walk.evicted);
+
+ /* We hit the low limit? Try once more */
+ if (!lret && evict_walk.hit_low && !evict_walk.try_low) {
+ evict_walk.try_low = true;
+ goto retry;
+ }
out:
if (lret < 0)
return lret;
@@ -689,6 +719,7 @@ static int ttm_bo_alloc_resource(struct ttm_buffer_object *bo,
for (i = 0; i < placement->num_placement; ++i) {
const struct ttm_place *place = &placement->placement[i];
+ struct dmem_cgroup_pool_state *limit_pool = NULL;
struct ttm_resource_manager *man;
bool may_evict;
@@ -701,15 +732,20 @@ static int ttm_bo_alloc_resource(struct ttm_buffer_object *bo,
continue;
may_evict = (force_space && place->mem_type != TTM_PL_SYSTEM);
- ret = ttm_resource_alloc(bo, place, res);
+ ret = ttm_resource_alloc(bo, place, res, force_space ? &limit_pool : NULL);
if (ret) {
- if (ret != -ENOSPC)
+ if (ret != -ENOSPC && ret != -EAGAIN) {
+ dmem_cgroup_pool_state_put(limit_pool);
return ret;
- if (!may_evict)
+ }
+ if (!may_evict) {
+ dmem_cgroup_pool_state_put(limit_pool);
continue;
+ }
ret = ttm_bo_evict_alloc(bdev, man, place, bo, ctx,
- ticket, res);
+ ticket, res, limit_pool);
+ dmem_cgroup_pool_state_put(limit_pool);
if (ret == -EBUSY)
continue;
if (ret)
@@ -1056,6 +1092,8 @@ struct ttm_bo_swapout_walk {
struct ttm_lru_walk walk;
/** @gfp_flags: The gfp flags to use for ttm_tt_swapout() */
gfp_t gfp_flags;
+
+ bool hit_low, evict_low;
};
static s64
@@ -1106,7 +1144,7 @@ ttm_bo_swapout_cb(struct ttm_lru_walk *walk, struct ttm_buffer_object *bo)
memset(&hop, 0, sizeof(hop));
place.mem_type = TTM_PL_SYSTEM;
- ret = ttm_resource_alloc(bo, &place, &evict_mem);
+ ret = ttm_resource_alloc(bo, &place, &evict_mem, NULL);
if (ret)
goto out;
diff --git a/drivers/gpu/drm/ttm/ttm_resource.c b/drivers/gpu/drm/ttm/ttm_resource.c
index a87665eb28a62..cc29bbf3eabb1 100644
--- a/drivers/gpu/drm/ttm/ttm_resource.c
+++ b/drivers/gpu/drm/ttm/ttm_resource.c
@@ -26,6 +26,7 @@
#include <linux/io-mapping.h>
#include <linux/iosys-map.h>
#include <linux/scatterlist.h>
+#include <linux/cgroup_dmem.h>
#include <drm/ttm/ttm_bo.h>
#include <drm/ttm/ttm_placement.h>
@@ -350,15 +351,28 @@ EXPORT_SYMBOL(ttm_resource_fini);
int ttm_resource_alloc(struct ttm_buffer_object *bo,
const struct ttm_place *place,
- struct ttm_resource **res_ptr)
+ struct ttm_resource **res_ptr,
+ struct dmem_cgroup_pool_state **ret_limit_pool)
{
struct ttm_resource_manager *man =
ttm_manager_type(bo->bdev, place->mem_type);
+ struct dmem_cgroup_pool_state *pool = NULL;
int ret;
+ if (man->cg) {
+ ret = dmem_cgroup_try_charge(man->cg, bo->base.size, &pool, ret_limit_pool);
+ if (ret)
+ return ret;
+ }
+
ret = man->func->alloc(man, bo, place, res_ptr);
- if (ret)
+ if (ret) {
+ if (pool)
+ dmem_cgroup_uncharge(pool, bo->base.size);
return ret;
+ }
+
+ (*res_ptr)->css = pool;
spin_lock(&bo->bdev->lru_lock);
ttm_resource_add_bulk_move(*res_ptr, bo);
@@ -370,6 +384,7 @@ EXPORT_SYMBOL_FOR_TESTS_ONLY(ttm_resource_alloc);
void ttm_resource_free(struct ttm_buffer_object *bo, struct ttm_resource **res)
{
struct ttm_resource_manager *man;
+ struct dmem_cgroup_pool_state *pool;
if (!*res)
return;
@@ -377,9 +392,13 @@ void ttm_resource_free(struct ttm_buffer_object *bo, struct ttm_resource **res)
spin_lock(&bo->bdev->lru_lock);
ttm_resource_del_bulk_move(*res, bo);
spin_unlock(&bo->bdev->lru_lock);
+
+ pool = (*res)->css;
man = ttm_manager_type(bo->bdev, (*res)->mem_type);
man->func->free(man, *res);
*res = NULL;
+ if (man->cg)
+ dmem_cgroup_uncharge(pool, bo->base.size);
}
EXPORT_SYMBOL(ttm_resource_free);
diff --git a/include/drm/ttm/ttm_resource.h b/include/drm/ttm/ttm_resource.h
index be034be56ba1b..ee688d0c029b3 100644
--- a/include/drm/ttm/ttm_resource.h
+++ b/include/drm/ttm/ttm_resource.h
@@ -38,6 +38,7 @@
#define TTM_MAX_BO_PRIORITY 4U
#define TTM_NUM_MEM_TYPES 8
+struct dmem_cgroup_device;
struct ttm_device;
struct ttm_resource_manager;
struct ttm_resource;
@@ -211,6 +212,11 @@ struct ttm_resource_manager {
* bdev->lru_lock.
*/
uint64_t usage;
+
+ /**
+ * @cg: &dmem_cgroup_region used for memory accounting, if not NULL.
+ */
+ struct dmem_cgroup_region *cg;
};
/**
@@ -239,6 +245,7 @@ struct ttm_bus_placement {
* @placement: Placement flags.
* @bus: Placement on io bus accessible to the CPU
* @bo: weak reference to the BO, protected by ttm_device::lru_lock
+ * @css: cgroup state this resource is charged to
*
* Structure indicating the placement and space resources used by a
* buffer object.
@@ -251,6 +258,8 @@ struct ttm_resource {
struct ttm_bus_placement bus;
struct ttm_buffer_object *bo;
+ struct dmem_cgroup_pool_state *css;
+
/**
* @lru: Least recently used list, see &ttm_resource_manager.lru
*/
@@ -432,7 +441,8 @@ void ttm_resource_fini(struct ttm_resource_manager *man,
int ttm_resource_alloc(struct ttm_buffer_object *bo,
const struct ttm_place *place,
- struct ttm_resource **res);
+ struct ttm_resource **res,
+ struct dmem_cgroup_pool_state **ret_limit_pool);
void ttm_resource_free(struct ttm_buffer_object *bo, struct ttm_resource **res);
bool ttm_resource_intersects(struct ttm_device *bdev,
struct ttm_resource *res,
--
2.43.0
