2019-01-22 15:27:54

by Greg Kroah-Hartman

Subject: [PATCH] iwlwifi: dvm: no need to check return value of debugfs_create functions

When calling debugfs functions, there is no need to ever check the
return value. The function can work or not, but the code logic should
never do something different based on this.

Cc: Johannes Berg <[email protected]>
Cc: Emmanuel Grumbach <[email protected]>
Cc: Luca Coelho <[email protected]>
Cc: Intel Linux Wireless <[email protected]>
Cc: Kalle Valo <[email protected]>
Cc: [email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>
---
drivers/net/wireless/intel/iwlwifi/dvm/agn.h | 9 ++--
.../net/wireless/intel/iwlwifi/dvm/debugfs.c | 44 ++-----------------
drivers/net/wireless/intel/iwlwifi/dvm/main.c | 5 +--
3 files changed, 8 insertions(+), 50 deletions(-)

diff --git a/drivers/net/wireless/intel/iwlwifi/dvm/agn.h b/drivers/net/wireless/intel/iwlwifi/dvm/agn.h
index 431e13c6ee35..254a5ce52456 100644
--- a/drivers/net/wireless/intel/iwlwifi/dvm/agn.h
+++ b/drivers/net/wireless/intel/iwlwifi/dvm/agn.h
@@ -439,13 +439,10 @@ static inline void iwl_dvm_set_pmi(struct iwl_priv *priv, bool state)
}

#ifdef CONFIG_IWLWIFI_DEBUGFS
-int iwl_dbgfs_register(struct iwl_priv *priv, struct dentry *dbgfs_dir);
+void iwl_dbgfs_register(struct iwl_priv *priv, struct dentry *dbgfs_dir);
#else
-static inline int iwl_dbgfs_register(struct iwl_priv *priv,
- struct dentry *dbgfs_dir)
-{
- return 0;
-}
+static inline void iwl_dbgfs_register(struct iwl_priv *priv,
+ struct dentry *dbgfs_dir) { }
#endif /* CONFIG_IWLWIFI_DEBUGFS */

#ifdef CONFIG_IWLWIFI_DEBUG
diff --git a/drivers/net/wireless/intel/iwlwifi/dvm/debugfs.c b/drivers/net/wireless/intel/iwlwifi/dvm/debugfs.c
index 3d2e44a642de..2ee9e4e28dba 100644
--- a/drivers/net/wireless/intel/iwlwifi/dvm/debugfs.c
+++ b/drivers/net/wireless/intel/iwlwifi/dvm/debugfs.c
@@ -36,31 +36,8 @@

/* create and remove of files */
#define DEBUGFS_ADD_FILE(name, parent, mode) do { \
- if (!debugfs_create_file(#name, mode, parent, priv, \
- &iwl_dbgfs_##name##_ops)) \
- goto err; \
-} while (0)
-
-#define DEBUGFS_ADD_BOOL(name, parent, ptr) do { \
- struct dentry *__tmp; \
- __tmp = debugfs_create_bool(#name, 0600, parent, ptr); \
- if (IS_ERR(__tmp) || !__tmp) \
- goto err; \
-} while (0)
-
-#define DEBUGFS_ADD_X32(name, parent, ptr) do { \
- struct dentry *__tmp; \
- __tmp = debugfs_create_x32(#name, 0600, parent, ptr); \
- if (IS_ERR(__tmp) || !__tmp) \
- goto err; \
-} while (0)
-
-#define DEBUGFS_ADD_U32(name, parent, ptr, mode) do { \
- struct dentry *__tmp; \
- __tmp = debugfs_create_u32(#name, mode, \
- parent, ptr); \
- if (IS_ERR(__tmp) || !__tmp) \
- goto err; \
+ debugfs_create_file(#name, mode, parent, priv, \
+ &iwl_dbgfs_##name##_ops); \
} while (0)

/* file operation */
@@ -2347,21 +2324,15 @@ DEBUGFS_READ_WRITE_FILE_OPS(calib_disabled);
* Create the debugfs files and directories
*
*/
-int iwl_dbgfs_register(struct iwl_priv *priv, struct dentry *dbgfs_dir)
+void iwl_dbgfs_register(struct iwl_priv *priv, struct dentry *dbgfs_dir)
{
struct dentry *dir_data, *dir_rf, *dir_debug;

priv->debugfs_dir = dbgfs_dir;

dir_data = debugfs_create_dir("data", dbgfs_dir);
- if (!dir_data)
- goto err;
dir_rf = debugfs_create_dir("rf", dbgfs_dir);
- if (!dir_rf)
- goto err;
dir_debug = debugfs_create_dir("debug", dbgfs_dir);
- if (!dir_debug)
- goto err;

DEBUGFS_ADD_FILE(nvm, dir_data, 0400);
DEBUGFS_ADD_FILE(sram, dir_data, 0600);
@@ -2421,13 +2392,6 @@ int iwl_dbgfs_register(struct iwl_priv *priv, struct dentry *dbgfs_dir)

snprintf(buf, 100, "../../%pd2", dev_dir);

- if (!debugfs_create_symlink("iwlwifi", mac80211_dir, buf))
- goto err;
+ debugfs_create_symlink("iwlwifi", mac80211_dir, buf);
}
-
- return 0;
-
-err:
- IWL_ERR(priv, "failed to create the dvm debugfs entries\n");
- return -ENOMEM;
}
diff --git a/drivers/net/wireless/intel/iwlwifi/dvm/main.c b/drivers/net/wireless/intel/iwlwifi/dvm/main.c
index c219bca5cff4..bd912b6a0b38 100644
--- a/drivers/net/wireless/intel/iwlwifi/dvm/main.c
+++ b/drivers/net/wireless/intel/iwlwifi/dvm/main.c
@@ -1509,13 +1509,10 @@ static struct iwl_op_mode *iwl_op_mode_dvm_start(struct iwl_trans *trans,
if (iwlagn_mac_setup_register(priv, &fw->ucode_capa))
goto out_destroy_workqueue;

- if (iwl_dbgfs_register(priv, dbgfs_dir))
- goto out_mac80211_unregister;
+ iwl_dbgfs_register(priv, dbgfs_dir);

return op_mode;

-out_mac80211_unregister:
- iwlagn_mac_unregister(priv);
out_destroy_workqueue:
iwl_tt_exit(priv);
iwl_cancel_deferred_work(priv);
--
2.20.1

2019-01-25 19:30:04

by Luciano Coelho

Subject: Re: [PATCH] iwlwifi: dvm: no need to check return value of debugfs_create functions

On Tue, 2019-01-22 at 16:21 +0100, Greg Kroah-Hartman wrote:
> When calling debugfs functions, there is no need to ever check the
> return value. The function can work or not, but the code logic
> should
> never do something different based on this.
>
> Cc: Johannes Berg <[email protected]>
> Cc: Emmanuel Grumbach <[email protected]>
> Cc: Luca Coelho <[email protected]>
> Cc: Intel Linux Wireless <[email protected]>
> Cc: Kalle Valo <[email protected]>
> Cc: [email protected]
> Signed-off-by: Greg Kroah-Hartman <[email protected]>
> ---

Thanks, Greg! I applied this in our internal tree and it will reach
upstream following our normal upstreaming process.

--
Cheers,
Luca.