2016-12-07 15:15:35

by Arvind Yadav

Subject: [PATCH V1] mtd : nand : denali :- No need of devm functions

In function denali_init, the memory allocated for denali->buf.buf
is live within the function only. After the allocation it is
immediately freed with devm_kfree. There is no need to allocate
memory for denali->buf.buf with devm function so replace
devm_kzalloc with kzalloc and devm_kfree with kfree.

Signed-off-by: Arvind Yadav <[email protected]>
---
drivers/mtd/nand/denali.c | 7 ++++---
1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/drivers/mtd/nand/denali.c b/drivers/mtd/nand/denali.c
index 0476ae8..ce3c31f 100644
--- a/drivers/mtd/nand/denali.c
+++ b/drivers/mtd/nand/denali.c
@@ -1476,8 +1476,7 @@ int denali_init(struct denali_nand_info *denali)
}

/* allocate a temporary buffer for nand_scan_ident() */
- denali->buf.buf = devm_kzalloc(denali->dev, PAGE_SIZE,
- GFP_DMA | GFP_KERNEL);
+ denali->buf.buf = kzalloc(PAGE_SIZE, GFP_DMA | GFP_KERNEL);
if (!denali->buf.buf)
return -ENOMEM;

@@ -1492,6 +1491,7 @@ int denali_init(struct denali_nand_info *denali)
if (request_irq(denali->irq, denali_isr, IRQF_SHARED,
DENALI_NAND_NAME, denali)) {
pr_err("Spectra: Unable to allocate IRQ\n");
+ kfree(denali->buf.buf);
return -ENODEV;
}

@@ -1512,11 +1512,12 @@ int denali_init(struct denali_nand_info *denali)
*/
if (nand_scan_ident(mtd, denali->max_banks, NULL)) {
ret = -ENXIO;
+ kfree(denali->buf.buf);
goto failed_req_irq;
}

/* allocate the right size buffer now */
- devm_kfree(denali->dev, denali->buf.buf);
+ kfree(denali->buf.buf);
denali->buf.buf = devm_kzalloc(denali->dev,
mtd->writesize + mtd->oobsize,
GFP_KERNEL);
--
2.7.4

2016-12-29 17:24:47

by Boris Brezillon

Subject: Re: [PATCH V1] mtd : nand : denali :- No need of devm functions

On Wed, 7 Dec 2016 20:45:11 +0530
Arvind Yadav <[email protected]> wrote:

> In function denali_init, the memory allocated for denali->buf.buf
> is live within the function only. After the allocation it is
> immediately freed with devm_kfree. There is no need to allocate
> memory for denali->buf.buf with devm function so replace
> devm_kzalloc with kzalloc and devm_kfree with kfree.
>
> Signed-off-by: Arvind Yadav <[email protected]>
> ---
> drivers/mtd/nand/denali.c | 7 ++++---
> 1 file changed, 4 insertions(+), 3 deletions(-)

Not sure it's any better than the previous logic (see the diffstat). The
devm_kzalloc() approach has the benefit of simplifying the different
error paths.

>
> diff --git a/drivers/mtd/nand/denali.c b/drivers/mtd/nand/denali.c
> index 0476ae8..ce3c31f 100644
> --- a/drivers/mtd/nand/denali.c
> +++ b/drivers/mtd/nand/denali.c
> @@ -1476,8 +1476,7 @@ int denali_init(struct denali_nand_info *denali)
> }
>
> /* allocate a temporary buffer for nand_scan_ident() */
> - denali->buf.buf = devm_kzalloc(denali->dev, PAGE_SIZE,
> - GFP_DMA | GFP_KERNEL);
> + denali->buf.buf = kzalloc(PAGE_SIZE, GFP_DMA | GFP_KERNEL);
> if (!denali->buf.buf)
> return -ENOMEM;
>
> @@ -1492,6 +1491,7 @@ int denali_init(struct denali_nand_info *denali)
> if (request_irq(denali->irq, denali_isr, IRQF_SHARED,
> DENALI_NAND_NAME, denali)) {
> pr_err("Spectra: Unable to allocate IRQ\n");
> + kfree(denali->buf.buf);
> return -ENODEV;
> }
>
> @@ -1512,11 +1512,12 @@ int denali_init(struct denali_nand_info *denali)
> */
> if (nand_scan_ident(mtd, denali->max_banks, NULL)) {
> ret = -ENXIO;
> + kfree(denali->buf.buf);
> goto failed_req_irq;
> }
>
> /* allocate the right size buffer now */
> - devm_kfree(denali->dev, denali->buf.buf);
> + kfree(denali->buf.buf);
> denali->buf.buf = devm_kzalloc(denali->dev,
> mtd->writesize + mtd->oobsize,
> GFP_KERNEL);