diff mbox series

[v2,2/4] udmabuf: change folios array from kmalloc to kvmalloc

Message ID 20240805032550.3912454-3-link@vivo.com (mailing list archive)
State New, archived
Headers show
Series udmbuf bug fix and some improvements | expand

Commit Message

Huan Yang Aug. 5, 2024, 3:25 a.m. UTC
When PAGE_SIZE 4096, MAX_PAGE_ORDER 10, 64bit machine,
page_alloc only support 4MB.
If above this, trigger this warn and return NULL.

udmabuf can change size limit, if change it to 3072(3GB), and then alloc
3GB udmabuf, will fail create.

[ 4080.876581] ------------[ cut here ]------------
[ 4080.876843] WARNING: CPU: 3 PID: 2015 at mm/page_alloc.c:4556 __alloc_pages+0x2c8/0x350
[ 4080.878839] RIP: 0010:__alloc_pages+0x2c8/0x350
[ 4080.879470] Call Trace:
[ 4080.879473]  <TASK>
[ 4080.879473]  ? __alloc_pages+0x2c8/0x350
[ 4080.879475]  ? __warn.cold+0x8e/0xe8
[ 4080.880647]  ? __alloc_pages+0x2c8/0x350
[ 4080.880909]  ? report_bug+0xff/0x140
[ 4080.881175]  ? handle_bug+0x3c/0x80
[ 4080.881556]  ? exc_invalid_op+0x17/0x70
[ 4080.881559]  ? asm_exc_invalid_op+0x1a/0x20
[ 4080.882077]  ? udmabuf_create+0x131/0x400

Because MAX_PAGE_ORDER, kmalloc can max alloc 4096 * (1 << 10), 4MB
memory, each array entry is pointer(8byte), so can save 524288 pages(2GB).

Further more, costly order(order 3) may not be guaranteed that it can be
applied for, due to fragmentation.

This patch change udmabuf array use kvmalloc_array, this can fallback
alloc into vmalloc, which can guarantee allocation for any size and does
not affect the performance of kmalloc allocations.

Signed-off-by: Huan Yang <link@vivo.com>
Acked-by: Christian König <christian.koenig@amd.com>
---
 drivers/dma-buf/udmabuf.c | 26 +++++++++++++-------------
 1 file changed, 13 insertions(+), 13 deletions(-)

Comments

Kasireddy, Vivek Aug. 10, 2024, 1:29 a.m. UTC | #1
Hi Huan,

> 
> When PAGE_SIZE 4096, MAX_PAGE_ORDER 10, 64bit machine,
> page_alloc only support 4MB.
> If above this, trigger this warn and return NULL.
> 
> udmabuf can change size limit, if change it to 3072(3GB), and then alloc
> 3GB udmabuf, will fail create.
> 
> [ 4080.876581] ------------[ cut here ]------------
> [ 4080.876843] WARNING: CPU: 3 PID: 2015 at mm/page_alloc.c:4556
> __alloc_pages+0x2c8/0x350
> [ 4080.878839] RIP: 0010:__alloc_pages+0x2c8/0x350
> [ 4080.879470] Call Trace:
> [ 4080.879473]  <TASK>
> [ 4080.879473]  ? __alloc_pages+0x2c8/0x350
> [ 4080.879475]  ? __warn.cold+0x8e/0xe8
> [ 4080.880647]  ? __alloc_pages+0x2c8/0x350
> [ 4080.880909]  ? report_bug+0xff/0x140
> [ 4080.881175]  ? handle_bug+0x3c/0x80
> [ 4080.881556]  ? exc_invalid_op+0x17/0x70
> [ 4080.881559]  ? asm_exc_invalid_op+0x1a/0x20
> [ 4080.882077]  ? udmabuf_create+0x131/0x400
> 
> Because MAX_PAGE_ORDER, kmalloc can max alloc 4096 * (1 << 10), 4MB
> memory, each array entry is pointer(8byte), so can save 524288 pages(2GB).
> 
> Further more, costly order(order 3) may not be guaranteed that it can be
> applied for, due to fragmentation.
> 
> This patch change udmabuf array use kvmalloc_array, this can fallback
> alloc into vmalloc, which can guarantee allocation for any size and does
> not affect the performance of kmalloc allocations.
> 
> Signed-off-by: Huan Yang <link@vivo.com>
> Acked-by: Christian König <christian.koenig@amd.com>
> ---
>  drivers/dma-buf/udmabuf.c | 26 +++++++++++++-------------
>  1 file changed, 13 insertions(+), 13 deletions(-)
> 
> diff --git a/drivers/dma-buf/udmabuf.c b/drivers/dma-buf/udmabuf.c
> index 475268d4ebb1..af2391cea0bf 100644
> --- a/drivers/dma-buf/udmabuf.c
> +++ b/drivers/dma-buf/udmabuf.c
> @@ -73,7 +73,7 @@ static int vmap_udmabuf(struct dma_buf *buf, struct
> iosys_map *map)
> 
>  	dma_resv_assert_held(buf->resv);
> 
> -	pages = kmalloc_array(ubuf->pagecount, sizeof(*pages),
> GFP_KERNEL);
> +	pages = kvmalloc_array(ubuf->pagecount, sizeof(*pages),
> GFP_KERNEL);
>  	if (!pages)
>  		return -ENOMEM;
> 
> @@ -81,7 +81,7 @@ static int vmap_udmabuf(struct dma_buf *buf, struct
> iosys_map *map)
>  		pages[pg] = &ubuf->folios[pg]->page;
> 
>  	vaddr = vm_map_ram(pages, ubuf->pagecount, -1);
> -	kfree(pages);
> +	kvfree(pages);
>  	if (!vaddr)
>  		return -EINVAL;
> 
> @@ -189,8 +189,8 @@ static void release_udmabuf(struct dma_buf *buf)
>  		put_sg_table(dev, ubuf->sg, DMA_BIDIRECTIONAL);
> 
>  	unpin_all_folios(&ubuf->unpin_list);
> -	kfree(ubuf->offsets);
> -	kfree(ubuf->folios);
> +	kvfree(ubuf->offsets);
> +	kvfree(ubuf->folios);
>  	kfree(ubuf);
>  }
> 
> @@ -315,14 +315,14 @@ static long udmabuf_create(struct miscdevice
> *device,
>  	if (!ubuf->pagecount)
>  		goto err;
> 
> -	ubuf->folios = kmalloc_array(ubuf->pagecount, sizeof(*ubuf->folios),
> -				    GFP_KERNEL);
> +	ubuf->folios = kvmalloc_array(ubuf->pagecount, sizeof(*ubuf-
> >folios),
> +				      GFP_KERNEL);
>  	if (!ubuf->folios) {
>  		ret = -ENOMEM;
>  		goto err;
>  	}
> -	ubuf->offsets = kcalloc(ubuf->pagecount, sizeof(*ubuf->offsets),
> -				GFP_KERNEL);
> +	ubuf->offsets =
> +		kvcalloc(ubuf->pagecount, sizeof(*ubuf->offsets),
No strong opinion, but I'd prefer to keep the kvcalloc on the same line.
Regardless,

Acked-by: Vivek Kasireddy <vivek.kasireddy@intel.com>

> GFP_KERNEL);
>  	if (!ubuf->offsets) {
>  		ret = -ENOMEM;
>  		goto err;
> @@ -336,7 +336,7 @@ static long udmabuf_create(struct miscdevice
> *device,
>  			goto err;
> 
>  		pgcnt = list[i].size >> PAGE_SHIFT;
> -		folios = kmalloc_array(pgcnt, sizeof(*folios), GFP_KERNEL);
> +		folios = kvmalloc_array(pgcnt, sizeof(*folios), GFP_KERNEL);
>  		if (!folios) {
>  			ret = -ENOMEM;
>  			goto err;
> @@ -346,7 +346,7 @@ static long udmabuf_create(struct miscdevice
> *device,
>  		ret = memfd_pin_folios(memfd, list[i].offset, end,
>  				       folios, pgcnt, &pgoff);
>  		if (ret <= 0) {
> -			kfree(folios);
> +			kvfree(folios);
>  			if (!ret)
>  				ret = -EINVAL;
>  			goto err;
> @@ -375,7 +375,7 @@ static long udmabuf_create(struct miscdevice
> *device,
>  			}
>  		}
> 
> -		kfree(folios);
> +		kvfree(folios);
>  		fput(memfd);
>  		memfd = NULL;
>  	}
> @@ -391,8 +391,8 @@ static long udmabuf_create(struct miscdevice
> *device,
>  	if (memfd)
>  		fput(memfd);
>  	unpin_all_folios(&ubuf->unpin_list);
> -	kfree(ubuf->offsets);
> -	kfree(ubuf->folios);
> +	kvfree(ubuf->offsets);
> +	kvfree(ubuf->folios);
>  	kfree(ubuf);
>  	return ret;
>  }
> --
> 2.45.2
Huan Yang Aug. 12, 2024, 2:49 a.m. UTC | #2
在 2024/8/10 9:29, Kasireddy, Vivek 写道:
> [Some people who received this message don't often get email from vivek.kasireddy@intel.com. Learn why this is important at https://aka.ms/LearnAboutSenderIdentification ]
>
> Hi Huan,
>
>> When PAGE_SIZE 4096, MAX_PAGE_ORDER 10, 64bit machine,
>> page_alloc only support 4MB.
>> If above this, trigger this warn and return NULL.
>>
>> udmabuf can change size limit, if change it to 3072(3GB), and then alloc
>> 3GB udmabuf, will fail create.
>>
>> [ 4080.876581] ------------[ cut here ]------------
>> [ 4080.876843] WARNING: CPU: 3 PID: 2015 at mm/page_alloc.c:4556
>> __alloc_pages+0x2c8/0x350
>> [ 4080.878839] RIP: 0010:__alloc_pages+0x2c8/0x350
>> [ 4080.879470] Call Trace:
>> [ 4080.879473]  <TASK>
>> [ 4080.879473]  ? __alloc_pages+0x2c8/0x350
>> [ 4080.879475]  ? __warn.cold+0x8e/0xe8
>> [ 4080.880647]  ? __alloc_pages+0x2c8/0x350
>> [ 4080.880909]  ? report_bug+0xff/0x140
>> [ 4080.881175]  ? handle_bug+0x3c/0x80
>> [ 4080.881556]  ? exc_invalid_op+0x17/0x70
>> [ 4080.881559]  ? asm_exc_invalid_op+0x1a/0x20
>> [ 4080.882077]  ? udmabuf_create+0x131/0x400
>>
>> Because MAX_PAGE_ORDER, kmalloc can max alloc 4096 * (1 << 10), 4MB
>> memory, each array entry is pointer(8byte), so can save 524288 pages(2GB).
>>
>> Further more, costly order(order 3) may not be guaranteed that it can be
>> applied for, due to fragmentation.
>>
>> This patch change udmabuf array use kvmalloc_array, this can fallback
>> alloc into vmalloc, which can guarantee allocation for any size and does
>> not affect the performance of kmalloc allocations.
>>
>> Signed-off-by: Huan Yang <link@vivo.com>
>> Acked-by: Christian König <christian.koenig@amd.com>
>> ---
>>   drivers/dma-buf/udmabuf.c | 26 +++++++++++++-------------
>>   1 file changed, 13 insertions(+), 13 deletions(-)
>>
>> diff --git a/drivers/dma-buf/udmabuf.c b/drivers/dma-buf/udmabuf.c
>> index 475268d4ebb1..af2391cea0bf 100644
>> --- a/drivers/dma-buf/udmabuf.c
>> +++ b/drivers/dma-buf/udmabuf.c
>> @@ -73,7 +73,7 @@ static int vmap_udmabuf(struct dma_buf *buf, struct
>> iosys_map *map)
>>
>>        dma_resv_assert_held(buf->resv);
>>
>> -     pages = kmalloc_array(ubuf->pagecount, sizeof(*pages),
>> GFP_KERNEL);
>> +     pages = kvmalloc_array(ubuf->pagecount, sizeof(*pages),
>> GFP_KERNEL);
>>        if (!pages)
>>                return -ENOMEM;
>>
>> @@ -81,7 +81,7 @@ static int vmap_udmabuf(struct dma_buf *buf, struct
>> iosys_map *map)
>>                pages[pg] = &ubuf->folios[pg]->page;
>>
>>        vaddr = vm_map_ram(pages, ubuf->pagecount, -1);
>> -     kfree(pages);
>> +     kvfree(pages);
>>        if (!vaddr)
>>                return -EINVAL;
>>
>> @@ -189,8 +189,8 @@ static void release_udmabuf(struct dma_buf *buf)
>>                put_sg_table(dev, ubuf->sg, DMA_BIDIRECTIONAL);
>>
>>        unpin_all_folios(&ubuf->unpin_list);
>> -     kfree(ubuf->offsets);
>> -     kfree(ubuf->folios);
>> +     kvfree(ubuf->offsets);
>> +     kvfree(ubuf->folios);
>>        kfree(ubuf);
>>   }
>>
>> @@ -315,14 +315,14 @@ static long udmabuf_create(struct miscdevice
>> *device,
>>        if (!ubuf->pagecount)
>>                goto err;
>>
>> -     ubuf->folios = kmalloc_array(ubuf->pagecount, sizeof(*ubuf->folios),
>> -                                 GFP_KERNEL);
>> +     ubuf->folios = kvmalloc_array(ubuf->pagecount, sizeof(*ubuf-
>>> folios),
>> +                                   GFP_KERNEL);
>>        if (!ubuf->folios) {
>>                ret = -ENOMEM;
>>                goto err;
>>        }
>> -     ubuf->offsets = kcalloc(ubuf->pagecount, sizeof(*ubuf->offsets),
>> -                             GFP_KERNEL);
>> +     ubuf->offsets =
>> +             kvcalloc(ubuf->pagecount, sizeof(*ubuf->offsets),
> No strong opinion, but I'd prefer to keep the kvcalloc on the same line.
> Regardless,

This style is auto formatted by my clang-format with .clang-format set 
in kernel.

But, I chang into online:

     ubuf->offsets = kvcalloc(ubuf->pagecount, sizeof(*ubuf->offsets),
                  GFP_KERNEL);

checkpatch  also did not report any errors.

So, I can send the next version of the patch when needed.

Thanks.

>
> Acked-by: Vivek Kasireddy <vivek.kasireddy@intel.com>
>
>> GFP_KERNEL);
>>        if (!ubuf->offsets) {
>>                ret = -ENOMEM;
>>                goto err;
>> @@ -336,7 +336,7 @@ static long udmabuf_create(struct miscdevice
>> *device,
>>                        goto err;
>>
>>                pgcnt = list[i].size >> PAGE_SHIFT;
>> -             folios = kmalloc_array(pgcnt, sizeof(*folios), GFP_KERNEL);
>> +             folios = kvmalloc_array(pgcnt, sizeof(*folios), GFP_KERNEL);
>>                if (!folios) {
>>                        ret = -ENOMEM;
>>                        goto err;
>> @@ -346,7 +346,7 @@ static long udmabuf_create(struct miscdevice
>> *device,
>>                ret = memfd_pin_folios(memfd, list[i].offset, end,
>>                                       folios, pgcnt, &pgoff);
>>                if (ret <= 0) {
>> -                     kfree(folios);
>> +                     kvfree(folios);
>>                        if (!ret)
>>                                ret = -EINVAL;
>>                        goto err;
>> @@ -375,7 +375,7 @@ static long udmabuf_create(struct miscdevice
>> *device,
>>                        }
>>                }
>>
>> -             kfree(folios);
>> +             kvfree(folios);
>>                fput(memfd);
>>                memfd = NULL;
>>        }
>> @@ -391,8 +391,8 @@ static long udmabuf_create(struct miscdevice
>> *device,
>>        if (memfd)
>>                fput(memfd);
>>        unpin_all_folios(&ubuf->unpin_list);
>> -     kfree(ubuf->offsets);
>> -     kfree(ubuf->folios);
>> +     kvfree(ubuf->offsets);
>> +     kvfree(ubuf->folios);
>>        kfree(ubuf);
>>        return ret;
>>   }
>> --
>> 2.45.2
diff mbox series

Patch

diff --git a/drivers/dma-buf/udmabuf.c b/drivers/dma-buf/udmabuf.c
index 475268d4ebb1..af2391cea0bf 100644
--- a/drivers/dma-buf/udmabuf.c
+++ b/drivers/dma-buf/udmabuf.c
@@ -73,7 +73,7 @@  static int vmap_udmabuf(struct dma_buf *buf, struct iosys_map *map)
 
 	dma_resv_assert_held(buf->resv);
 
-	pages = kmalloc_array(ubuf->pagecount, sizeof(*pages), GFP_KERNEL);
+	pages = kvmalloc_array(ubuf->pagecount, sizeof(*pages), GFP_KERNEL);
 	if (!pages)
 		return -ENOMEM;
 
@@ -81,7 +81,7 @@  static int vmap_udmabuf(struct dma_buf *buf, struct iosys_map *map)
 		pages[pg] = &ubuf->folios[pg]->page;
 
 	vaddr = vm_map_ram(pages, ubuf->pagecount, -1);
-	kfree(pages);
+	kvfree(pages);
 	if (!vaddr)
 		return -EINVAL;
 
@@ -189,8 +189,8 @@  static void release_udmabuf(struct dma_buf *buf)
 		put_sg_table(dev, ubuf->sg, DMA_BIDIRECTIONAL);
 
 	unpin_all_folios(&ubuf->unpin_list);
-	kfree(ubuf->offsets);
-	kfree(ubuf->folios);
+	kvfree(ubuf->offsets);
+	kvfree(ubuf->folios);
 	kfree(ubuf);
 }
 
@@ -315,14 +315,14 @@  static long udmabuf_create(struct miscdevice *device,
 	if (!ubuf->pagecount)
 		goto err;
 
-	ubuf->folios = kmalloc_array(ubuf->pagecount, sizeof(*ubuf->folios),
-				    GFP_KERNEL);
+	ubuf->folios = kvmalloc_array(ubuf->pagecount, sizeof(*ubuf->folios),
+				      GFP_KERNEL);
 	if (!ubuf->folios) {
 		ret = -ENOMEM;
 		goto err;
 	}
-	ubuf->offsets = kcalloc(ubuf->pagecount, sizeof(*ubuf->offsets),
-				GFP_KERNEL);
+	ubuf->offsets =
+		kvcalloc(ubuf->pagecount, sizeof(*ubuf->offsets), GFP_KERNEL);
 	if (!ubuf->offsets) {
 		ret = -ENOMEM;
 		goto err;
@@ -336,7 +336,7 @@  static long udmabuf_create(struct miscdevice *device,
 			goto err;
 
 		pgcnt = list[i].size >> PAGE_SHIFT;
-		folios = kmalloc_array(pgcnt, sizeof(*folios), GFP_KERNEL);
+		folios = kvmalloc_array(pgcnt, sizeof(*folios), GFP_KERNEL);
 		if (!folios) {
 			ret = -ENOMEM;
 			goto err;
@@ -346,7 +346,7 @@  static long udmabuf_create(struct miscdevice *device,
 		ret = memfd_pin_folios(memfd, list[i].offset, end,
 				       folios, pgcnt, &pgoff);
 		if (ret <= 0) {
-			kfree(folios);
+			kvfree(folios);
 			if (!ret)
 				ret = -EINVAL;
 			goto err;
@@ -375,7 +375,7 @@  static long udmabuf_create(struct miscdevice *device,
 			}
 		}
 
-		kfree(folios);
+		kvfree(folios);
 		fput(memfd);
 		memfd = NULL;
 	}
@@ -391,8 +391,8 @@  static long udmabuf_create(struct miscdevice *device,
 	if (memfd)
 		fput(memfd);
 	unpin_all_folios(&ubuf->unpin_list);
-	kfree(ubuf->offsets);
-	kfree(ubuf->folios);
+	kvfree(ubuf->offsets);
+	kvfree(ubuf->folios);
 	kfree(ubuf);
 	return ret;
 }