[PATCH -next v2 1/2] media: cec: remove redundant null pointer checks in cec_devnode_init()

[PATCH -next v2 1/2] media: cec: remove redundant null pointer checks in cec_devnode_init()

[Li Zetao]

Since the debugfs_create_dir() never returns a null pointer, checking
the return value for a null pointer is redundant. Remove this check
since debugfs_create_file can handle IS_ERR pointers. At the same time,
debugfs_create_dir returns ERR_PTR (-ENODEV) by default when
CONFIG_DEBUG_FS=N, so there is no need for CONFIG_DEBUG_FS macro
isolation.

Signed-off-by: Li Zetao <lizetao1@huawei.com>
---
v1 -> v2: Remove this check since debugfs_create_file can handle IS_ERR
pointers. And drop the ifdef CONFIG_DEBUG_FS statement.
v1:
https://lore.kernel.org/all/20240903143607.2004802-1-lizetao1@huawei.com/

 drivers/media/cec/core/cec-core.c | 6 ------
 1 file changed, 6 deletions(-)

diff --git a/drivers/media/cec/core/cec-core.c b/drivers/media/cec/core/cec-core.c
index e0756826d629..77be6c11c63c 100644
--- a/drivers/media/cec/core/cec-core.c
+++ b/drivers/media/cec/core/cec-core.c
@@ -439,13 +439,7 @@ static int __init cec_devnode_init(void)
 		return ret;
 	}
 
-#ifdef CONFIG_DEBUG_FS
 	top_cec_dir = debugfs_create_dir("cec", NULL);
-	if (IS_ERR_OR_NULL(top_cec_dir)) {
-		pr_warn("cec: Failed to create debugfs cec dir\n");
-		top_cec_dir = NULL;
-	}
-#endif
 
 	ret = bus_register(&cec_bus_type);
 	if (ret < 0) {
-- 
2.34.1

[PATCH -next v2 2/2] media: siano: remove redundant null pointer checks in cec_devnode_init()

[Li Zetao]

Since the debugfs_create_dir() never returns a null pointer, checking
the return value for a null pointer is redundant, Remove this check
since debugfs_create_file can handle IS_ERR pointers.

Signed-off-by: Li Zetao <lizetao1@huawei.com>
---
v1 -> v2: Remove this check since debugfs_create_file can
handle IS_ERR pointers.
v1:
https://lore.kernel.org/all/20240903143607.2004802-2-lizetao1@huawei.com/

 drivers/media/common/siano/smsdvb-debugfs.c | 4 ----
 1 file changed, 4 deletions(-)

diff --git a/drivers/media/common/siano/smsdvb-debugfs.c b/drivers/media/common/siano/smsdvb-debugfs.c
index 73990e469df9..9db38ae4ecee 100644
--- a/drivers/media/common/siano/smsdvb-debugfs.c
+++ b/drivers/media/common/siano/smsdvb-debugfs.c
@@ -411,10 +411,6 @@ void smsdvb_debugfs_register(void)
 	 * subsystem.
 	 */
 	d = debugfs_create_dir("smsdvb", usb_debug_root);
-	if (IS_ERR_OR_NULL(d)) {
-		pr_err("Couldn't create sysfs node for smsdvb\n");
-		return;
-	}
 	smsdvb_debugfs_usb_root = d;
 }
 
-- 
2.34.1

Re: [PATCH -next v2 2/2] media: siano: remove redundant null pointer checks in cec_devnode_init()

[Greg KH]

On Sat, Sep 07, 2024 at 11:44:00AM +0800, Li Zetao wrote:
> Since the debugfs_create_dir() never returns a null pointer, checking
> the return value for a null pointer is redundant, Remove this check
> since debugfs_create_file can handle IS_ERR pointers.
> 
> Signed-off-by: Li Zetao <lizetao1@huawei.com>
> ---
> v1 -> v2: Remove this check since debugfs_create_file can
> handle IS_ERR pointers.
> v1:
> https://lore.kernel.org/all/20240903143607.2004802-2-lizetao1@huawei.com/
> 
>  drivers/media/common/siano/smsdvb-debugfs.c | 4 ----
>  1 file changed, 4 deletions(-)
> 
> diff --git a/drivers/media/common/siano/smsdvb-debugfs.c b/drivers/media/common/siano/smsdvb-debugfs.c
> index 73990e469df9..9db38ae4ecee 100644
> --- a/drivers/media/common/siano/smsdvb-debugfs.c
> +++ b/drivers/media/common/siano/smsdvb-debugfs.c
> @@ -411,10 +411,6 @@ void smsdvb_debugfs_register(void)
>  	 * subsystem.
>  	 */
>  	d = debugfs_create_dir("smsdvb", usb_debug_root);
> -	if (IS_ERR_OR_NULL(d)) {
> -		pr_err("Couldn't create sysfs node for smsdvb\n");
> -		return;
> -	}
>  	smsdvb_debugfs_usb_root = d;

Why is d even needed here, just assign it to smsdvb_debugfs_usb_root
directly, right?

thanks,

greg k-h

Re: [PATCH -next v2 1/2] media: cec: remove redundant null pointer checks in cec_devnode_init()

[Hans Verkuil]

On 07/09/2024 05:43, Li Zetao wrote:
> Since the debugfs_create_dir() never returns a null pointer, checking
> the return value for a null pointer is redundant. Remove this check
> since debugfs_create_file can handle IS_ERR pointers. At the same time,
> debugfs_create_dir returns ERR_PTR (-ENODEV) by default when
> CONFIG_DEBUG_FS=N, so there is no need for CONFIG_DEBUG_FS macro
> isolation.
> 
> Signed-off-by: Li Zetao <lizetao1@huawei.com>
> ---
> v1 -> v2: Remove this check since debugfs_create_file can handle IS_ERR
> pointers. And drop the ifdef CONFIG_DEBUG_FS statement.
> v1:
> https://lore.kernel.org/all/20240903143607.2004802-1-lizetao1@huawei.com/
> 
>  drivers/media/cec/core/cec-core.c | 6 ------
>  1 file changed, 6 deletions(-)
> 
> diff --git a/drivers/media/cec/core/cec-core.c b/drivers/media/cec/core/cec-core.c
> index e0756826d629..77be6c11c63c 100644
> --- a/drivers/media/cec/core/cec-core.c
> +++ b/drivers/media/cec/core/cec-core.c
> @@ -439,13 +439,7 @@ static int __init cec_devnode_init(void)
>  		return ret;
>  	}
>  
> -#ifdef CONFIG_DEBUG_FS
>  	top_cec_dir = debugfs_create_dir("cec", NULL);
> -	if (IS_ERR_OR_NULL(top_cec_dir)) {
> -		pr_warn("cec: Failed to create debugfs cec dir\n");
> -		top_cec_dir = NULL;
> -	}
> -#endif
>  
>  	ret = bus_register(&cec_bus_type);
>  	if (ret < 0) {

Check all users of top_cec_dir, you'll need to make more changes in this source.

Regards,

	Hans

[PATCH net-next v2 00/10] net: Convert using devm_clk_get_enabled()/devm_clk_get_optional_enabled()

[Li Zetao]

v1 -> v2:
  1) Patch 5 optimizes the check and adds commit information for easier
  inspection.
  2) It is no longer necessary to use clk, so delete the clk member of
  the spl2sw_common structure.
  3) Remove patches 11 and 12, they should be sent to wireless-next
  individually

v1:
https://lore.kernel.org/all/20240831021334.1907921-1-lizetao1@huawei.com/

There are many examples[1][2] of clk resource leakage in LTS. The
reason is that developers need to maintain the allocation and release
of clk resources themselves, but this will increase the burden on
developers. Using the API related to devm_clk_get_*_enable ensures
that the life cycle of clk is consistent with that of the device,
reducing the risk of unreleased resources like clk.

Several other developers are also working on converting to more
secure interfaces, and this patch set is in principle the same as
theirs.

[1]:
https://lore.kernel.org/all/20240812160128.338041191@linuxfoundation.org/
[2]:
https://lore.kernel.org/all/20240812160135.992451065@linuxfoundation.org/

Li Zetao (10):
  net: dsa: bcm_sf2: Convert using devm_clk_get_optional_enabled() in
    bcm_sf2_sw_probe()
  net: ethernet: Convert using devm_clk_get_enabled() in emac_probe()
  net: ethernet: arc: Convert using devm_clk_get_enabled() in
    emac_probe()
  net: ethernet: ethoc: Convert using devm_clk_get_enabled() in
    ethoc_probe()
  net: ftgmac100: Convert using devm_clk_get_enabled() in
    ftgmac100_setup_clk()
  net: ethernet: hisilicon: Convert using devm_clk_get_enabled() in
    hisi_femac_drv_probe()
  net: lantiq_xrx200: Convert using devm_clk_get_enabled() in
    xrx200_probe()
  net: stmmac: dwmac-dwc-qos-eth: Convert using devm_clk_get_enabled()
    in dwc_qos_probe()
  net: ethernet: sunplus: Convert using devm_clk_get_enabled() in
    spl2sw_probe()
  net: xilinx: axienet: Convert using devm_clk_get_optional_enabled() in
    axienet_probe()

 drivers/net/dsa/bcm_sf2.c                     | 28 ++----
 drivers/net/ethernet/allwinner/sun4i-emac.c   | 13 +--
 drivers/net/ethernet/arc/emac_rockchip.c      | 34 ++-----
 drivers/net/ethernet/ethoc.c                  | 18 ++--
 drivers/net/ethernet/faraday/ftgmac100.c      | 26 +----
 drivers/net/ethernet/hisilicon/hisi_femac.c   | 17 +---
 drivers/net/ethernet/lantiq_xrx200.c          | 17 +---
 .../stmicro/stmmac/dwmac-dwc-qos-eth.c        | 98 ++++---------------
 drivers/net/ethernet/sunplus/spl2sw_define.h  |  1 -
 drivers/net/ethernet/sunplus/spl2sw_driver.c  | 25 ++---
 .../net/ethernet/xilinx/xilinx_axienet_main.c | 15 +--
 11 files changed, 62 insertions(+), 230 deletions(-)

-- 
2.34.1

[PATCH -next v2 2/2] media: siano: remove redundant null pointer checks in cec_devnode_init()

[Li Zetao]

Since the debugfs_create_dir() never returns a null pointer, checking
the return value for a null pointer is redundant, Remove this check
since debugfs_create_file can handle IS_ERR pointers.

Signed-off-by: Li Zetao <lizetao1@huawei.com>
---
v1 -> v2: Remove this check since debugfs_create_file can
handle IS_ERR pointers.
v1:
https://lore.kernel.org/all/20240903143607.2004802-2-lizetao1@huawei.com/

 drivers/media/common/siano/smsdvb-debugfs.c | 4 ----
 1 file changed, 4 deletions(-)

diff --git a/drivers/media/common/siano/smsdvb-debugfs.c b/drivers/media/common/siano/smsdvb-debugfs.c
index 73990e469df9..9db38ae4ecee 100644
--- a/drivers/media/common/siano/smsdvb-debugfs.c
+++ b/drivers/media/common/siano/smsdvb-debugfs.c
@@ -411,10 +411,6 @@ void smsdvb_debugfs_register(void)
 	 * subsystem.
 	 */
 	d = debugfs_create_dir("smsdvb", usb_debug_root);
-	if (IS_ERR_OR_NULL(d)) {
-		pr_err("Couldn't create sysfs node for smsdvb\n");
-		return;
-	}
 	smsdvb_debugfs_usb_root = d;
 }
 
-- 
2.34.1