Following patch removes the uses of 'kmalloc+memset' from various drivers subsystems, which is replaced by kzalloc. kzalloc take care of setting allocated memory with null, so it helps to get rid from using memset.
Signed-off-by: Rakib Mullick <[email protected]>
---
diff --git a/drivers/ata/sata_dwc_460ex.c b/drivers/ata/sata_dwc_460ex.c
index 1c4b3aa..168b78f 100644
--- a/drivers/ata/sata_dwc_460ex.c
+++ b/drivers/ata/sata_dwc_460ex.c
@@ -1638,13 +1638,12 @@ static int sata_dwc_probe(struct platform_device *ofdev)
const struct ata_port_info *ppi[] = { &pi, NULL };
/* Allocate DWC SATA device */
- hsdev = kmalloc(sizeof(*hsdev), GFP_KERNEL);
+ hsdev = kzalloc(sizeof(*hsdev), GFP_KERNEL);
if (hsdev == NULL) {
dev_err(&ofdev->dev, "kmalloc failed for hsdev\n");
err = -ENOMEM;
goto error_out;
}
- memset(hsdev, 0, sizeof(*hsdev));
/* Ioremap SATA registers */
base = of_iomap(ofdev->dev.of_node, 0);
diff --git a/drivers/gpu/drm/drm_scatter.c b/drivers/gpu/drm/drm_scatter.c
index d15e09b..37db1f8 100644
--- a/drivers/gpu/drm/drm_scatter.c
+++ b/drivers/gpu/drm/drm_scatter.c
@@ -83,30 +83,26 @@ int drm_sg_alloc(struct drm_device *dev, struct drm_scatter_gather * request)
if (dev->sg)
return -EINVAL;
- entry = kmalloc(sizeof(*entry), GFP_KERNEL);
+ entry = kzalloc(sizeof(*entry), GFP_KERNEL);
if (!entry)
return -ENOMEM;
- memset(entry, 0, sizeof(*entry));
pages = (request->size + PAGE_SIZE - 1) / PAGE_SIZE;
DRM_DEBUG("size=%ld pages=%ld\n", request->size, pages);
entry->pages = pages;
- entry->pagelist = kmalloc(pages * sizeof(*entry->pagelist), GFP_KERNEL);
+ entry->pagelist = kzalloc(pages * sizeof(*entry->pagelist), GFP_KERNEL);
if (!entry->pagelist) {
kfree(entry);
return -ENOMEM;
}
- memset(entry->pagelist, 0, pages * sizeof(*entry->pagelist));
-
- entry->busaddr = kmalloc(pages * sizeof(*entry->busaddr), GFP_KERNEL);
+ entry->busaddr = kzalloc(pages * sizeof(*entry->busaddr), GFP_KERNEL);
if (!entry->busaddr) {
kfree(entry->pagelist);
kfree(entry);
return -ENOMEM;
}
- memset((void *)entry->busaddr, 0, pages * sizeof(*entry->busaddr));
entry->virtual = drm_vmalloc_dma(pages << PAGE_SHIFT);
if (!entry->virtual) {
diff --git a/drivers/gpu/drm/radeon/radeon_mem.c b/drivers/gpu/drm/radeon/radeon_mem.c
index ed95155..988548e 100644
--- a/drivers/gpu/drm/radeon/radeon_mem.c
+++ b/drivers/gpu/drm/radeon/radeon_mem.c
@@ -139,7 +139,7 @@ static int init_heap(struct mem_block **heap, int start, int size)
if (!blocks)
return -ENOMEM;
- *heap = kmalloc(sizeof(**heap), GFP_KERNEL);
+ *heap = kzalloc(sizeof(**heap), GFP_KERNEL);
if (!*heap) {
kfree(blocks);
return -ENOMEM;
@@ -150,7 +150,6 @@ static int init_heap(struct mem_block **heap, int start, int size)
blocks->file_priv = NULL;
blocks->next = blocks->prev = *heap;
- memset(*heap, 0, sizeof(**heap));
(*heap)->file_priv = (struct drm_file *) - 1;
(*heap)->next = (*heap)->prev = blocks;
return 0;
diff --git a/drivers/gpu/drm/vmwgfx/vmwgfx_overlay.c b/drivers/gpu/drm/vmwgfx/vmwgfx_overlay.c
index f1a52f9..07ce02d 100644
--- a/drivers/gpu/drm/vmwgfx/vmwgfx_overlay.c
+++ b/drivers/gpu/drm/vmwgfx/vmwgfx_overlay.c
@@ -585,11 +585,10 @@ int vmw_overlay_init(struct vmw_private *dev_priv)
return -ENOSYS;
}
- overlay = kmalloc(sizeof(*overlay), GFP_KERNEL);
+ overlay = kzalloc(sizeof(*overlay), GFP_KERNEL);
if (!overlay)
return -ENOMEM;
- memset(overlay, 0, sizeof(*overlay));
mutex_init(&overlay->mutex);
for (i = 0; i < VMW_MAX_NUM_STREAMS; i++) {
overlay->stream[i].buf = NULL;
diff --git a/drivers/gpu/drm/vmwgfx/vmwgfx_resource.c b/drivers/gpu/drm/vmwgfx/vmwgfx_resource.c
index 5408b1b..bfe1bcc 100644
--- a/drivers/gpu/drm/vmwgfx/vmwgfx_resource.c
+++ b/drivers/gpu/drm/vmwgfx/vmwgfx_resource.c
@@ -612,11 +612,9 @@ int vmw_surface_define_ioctl(struct drm_device *dev, void *data,
srf->sizes[0].height == 64 &&
srf->format == SVGA3D_A8R8G8B8) {
- srf->snooper.image = kmalloc(64 * 64 * 4, GFP_KERNEL);
- /* clear the image */
- if (srf->snooper.image) {
- memset(srf->snooper.image, 0x00, 64 * 64 * 4);
- } else {
+ /* allocate image area and clear it */
+ srf->snooper.image = kzalloc(64 * 64 * 4, GFP_KERNEL);
+ if (!srf->snooper.image) {
DRM_ERROR("Failed to allocate cursor_image\n");
ret = -ENOMEM;
goto out_err1;
diff --git a/drivers/gpu/vga/vgaarb.c b/drivers/gpu/vga/vgaarb.c
index be8d4cb..370de0b 100644
--- a/drivers/gpu/vga/vgaarb.c
+++ b/drivers/gpu/vga/vgaarb.c
@@ -1094,10 +1094,9 @@ static int vga_arb_open(struct inode *inode, struct file *file)
pr_debug("%s\n", __func__);
- priv = kmalloc(sizeof(struct vga_arb_private), GFP_KERNEL);
+ priv = kzalloc(sizeof(*priv), GFP_KERNEL);
if (priv == NULL)
return -ENOMEM;
- memset(priv, 0, sizeof(*priv));
spin_lock_init(&priv->lock);
file->private_data = priv;
On Mon, 2011-05-23 at 23:40 +0600, Rakib Mullick wrote:
> Following patch removes the uses of 'kmalloc+memset' from various
> drivers subsystems, which is replaced by kzalloc. kzalloc take care of
> setting allocated memory with null, so it helps to get rid from using
> memset.
> diff --git a/drivers/gpu/drm/drm_scatter.c b/drivers/gpu/drm/drm_scatter.c
[]
> - entry->pagelist = kmalloc(pages * sizeof(*entry->pagelist), GFP_KERNEL);
> + entry->pagelist = kzalloc(pages * sizeof(*entry->pagelist), GFP_KERNEL);
Perhaps it's better to use:
entry->pagelist = kcalloc(pages, sizeof(*entry->pagelist), GFP_KERNEL);
> - entry->busaddr = kmalloc(pages * sizeof(*entry->busaddr), GFP_KERNEL);
> + entry->busaddr = kzalloc(pages * sizeof(*entry->busaddr), GFP_KERNEL);
here too.
On 5/23/11, Joe Perches <[email protected]> wrote:
> On Mon, 2011-05-23 at 23:40 +0600, Rakib Mullick wrote:
>> Following patch removes the uses of 'kmalloc+memset' from various
>> drivers subsystems, which is replaced by kzalloc. kzalloc take care of
>> setting allocated memory with null, so it helps to get rid from using
>> memset.
>> diff --git a/drivers/gpu/drm/drm_scatter.c b/drivers/gpu/drm/drm_scatter.c
> []
>> - entry->pagelist = kmalloc(pages * sizeof(*entry->pagelist), GFP_KERNEL);
>> + entry->pagelist = kzalloc(pages * sizeof(*entry->pagelist), GFP_KERNEL);
>
> Perhaps it's better to use:
>
> entry->pagelist = kcalloc(pages, sizeof(*entry->pagelist), GFP_KERNEL);
>
>> - entry->busaddr = kmalloc(pages * sizeof(*entry->busaddr), GFP_KERNEL);
>> + entry->busaddr = kzalloc(pages * sizeof(*entry->busaddr), GFP_KERNEL);
>
> here too.
>
Is there any significant benefit of using kcalloc here?
Thanks,
Rakib
>
On Tue, 2011-05-24 at 22:59 +0600, Rakib Mullick wrote:
> On 5/23/11, Joe Perches <[email protected]> wrote:
> > On Mon, 2011-05-23 at 23:40 +0600, Rakib Mullick wrote:
> >> Following patch removes the uses of 'kmalloc+memset' from various
> >> drivers subsystems, which is replaced by kzalloc. kzalloc take care of
> >> setting allocated memory with null, so it helps to get rid from using
> >> memset.
> >> diff --git a/drivers/gpu/drm/drm_scatter.c b/drivers/gpu/drm/drm_scatter.c
> > []
> >> - entry->pagelist = kmalloc(pages * sizeof(*entry->pagelist), GFP_KERNEL);
> >> + entry->pagelist = kzalloc(pages * sizeof(*entry->pagelist), GFP_KERNEL);
> > Perhaps it's better to use:
> > entry->pagelist = kcalloc(pages, sizeof(*entry->pagelist), GFP_KERNEL);
> >> - entry->busaddr = kmalloc(pages * sizeof(*entry->busaddr), GFP_KERNEL);
> >> + entry->busaddr = kzalloc(pages * sizeof(*entry->busaddr), GFP_KERNEL);
> > here too.
> Is there any significant benefit of using kcalloc here?
Overflow and tradition.
static inline void *kcalloc(size_t n, size_t size, gfp_t flags)
{
if (size != 0 && n > ULONG_MAX / size)
return NULL;
return __kmalloc(n * size, flags | __GFP_ZERO);
}