video: tegra: nvmap: Avoid double updation of RSS counter

The RSS counter is updated during buffer allocation as well as mmap,
which is leading to double updation. Fix this by decrementing the RSS
counter during page fault while increment it back during unmap flow.

Bug 5222690

Change-Id: I77972185f20d9d710571cc07ae1c5188060bfa1f
Signed-off-by: Ketan Patil <ketanp@nvidia.com>
Reviewed-on: https://git-master.nvidia.com/r/c/linux-nv-oot/+/3442670
(cherry picked from commit 1c59063ce7)
Reviewed-on: https://git-master.nvidia.com/r/c/linux-nv-oot/+/3453106
Tested-by: Amulya Yarlagadda <ayarlagadda@nvidia.com>
Reviewed-by: Amulya Yarlagadda <ayarlagadda@nvidia.com>
GVS: buildbot_gerritrpt <buildbot_gerritrpt@nvidia.com>
This commit is contained in:
Ketan Patil
2025-09-02 08:53:30 +00:00
committed by Amulya Yarlagadda
parent 5fc4079741
commit 08fbba8f59
3 changed files with 22 additions and 2 deletions

View File

@@ -1,6 +1,6 @@
// SPDX-License-Identifier: GPL-2.0-only // SPDX-License-Identifier: GPL-2.0-only
/* /*
* Copyright (c) 2012-2023, NVIDIA CORPORATION. All rights reserved. * Copyright (c) 2012-2025, NVIDIA CORPORATION. All rights reserved.
* *
* dma_buf exporter for nvmap * dma_buf exporter for nvmap
*/ */
@@ -450,6 +450,7 @@ int __nvmap_map(struct nvmap_handle *h, struct vm_area_struct *vma)
nvmap_handle_put(h); nvmap_handle_put(h);
return -ENOMEM; return -ENOMEM;
} }
mutex_init(&priv->vma_lock);
priv->handle = h; priv->handle = h;
#if defined(NV_VM_AREA_STRUCT_HAS_CONST_VM_FLAGS) /* Linux v6.3 */ #if defined(NV_VM_AREA_STRUCT_HAS_CONST_VM_FLAGS) /* Linux v6.3 */

View File

@@ -1,6 +1,6 @@
// SPDX-License-Identifier: GPL-2.0-only // SPDX-License-Identifier: GPL-2.0-only
/* /*
* Copyright (c) 2011-2023, NVIDIA CORPORATION. All rights reserved. * Copyright (c) 2011-2025, NVIDIA CORPORATION. All rights reserved.
*/ */
#define pr_fmt(fmt) "%s: " fmt, __func__ #define pr_fmt(fmt) "%s: " fmt, __func__
@@ -147,6 +147,14 @@ static void nvmap_vma_close(struct vm_area_struct *vma)
BUG_ON(!vma_found); BUG_ON(!vma_found);
nvmap_umaps_dec(h); nvmap_umaps_dec(h);
mutex_lock(&priv->vma_lock);
if (priv->mm != NULL && h->anon_count != 0) {
nvmap_add_mm_counter(priv->mm, MM_ANONPAGES, priv->map_rss_count);
priv->map_rss_count = 0;
priv->mm = NULL;
}
mutex_unlock(&priv->vma_lock);
if (__atomic_add_unless(&priv->count, -1, 0) == 1) { if (__atomic_add_unless(&priv->count, -1, 0) == 1) {
if (h->heap_pgalloc) { if (h->heap_pgalloc) {
for (i = 0; i < nr_page; i++) { for (i = 0; i < nr_page; i++) {
@@ -233,6 +241,14 @@ static int nvmap_vma_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
return VM_FAULT_SIGSEGV; return VM_FAULT_SIGSEGV;
} }
mutex_lock(&priv->vma_lock);
if (priv->handle->anon_count != 0 && current->mm != NULL) {
nvmap_add_mm_counter(current->mm, MM_ANONPAGES, -1);
priv->map_rss_count++;
priv->mm = current->mm;
}
mutex_unlock(&priv->vma_lock);
if (!nvmap_handle_track_dirty(priv->handle)) if (!nvmap_handle_track_dirty(priv->handle))
goto finish; goto finish;
mutex_lock(&priv->handle->lock); mutex_lock(&priv->handle->lock);

View File

@@ -380,6 +380,9 @@ struct nvmap_vma_priv {
struct nvmap_handle *handle; struct nvmap_handle *handle;
size_t offs; size_t offs;
atomic_t count; /* number of processes cloning the VMA */ atomic_t count; /* number of processes cloning the VMA */
u64 map_rss_count;
struct mm_struct *mm;
struct mutex vma_lock;
}; };
struct nvmap_device { struct nvmap_device {