staging: r8188eu: simplify control flow

PATCH Superseded Sevinj Aghayeva 3 participants 7 messages Apr 3, 2022 Staging

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Sevinj Aghayeva

author

2022-04-03 15:51 UTC #0 lore raw

PATCH 1/1 staging: r8188eu: simplify control flow

The function iterates an index from 0 to NUM_PMKID_CACHE and returns the first index for which the condition is true. If no such index is found, the function returns -1. Current code has a complex control flow that obfuscates this simple task. Replace it with a loop.

Also, given the shortened function body, replace the long variable name psecuritypriv with a short variable name p.

Reported by checkpatch:

WARNING: else is not generally useful after a break or return

Signed-off-by Sevinj Aghayeva <[email protected]>

---
 drivers/staging/r8188eu/core/rtw_mlme.c | 26 +++++++------------------
 1 file changed, 7 insertions(+), 19 deletions(-)

drivers/staging/r8188eu/core/rtw_mlme.c +7 ~~-19~~

index f94b1536a177..851092f61206 100644
@@ -1637,26 +1637,14 @@ int rtw_restruct_wmm_ie(struct adapter *adapter, u8 *in_ie, u8 *out_ie, uint in_
 
 static int SecIsInPMKIDList(struct adapter *Adapter, u8 *bssid)
 {
-	struct security_priv *psecuritypriv = &Adapter->securitypriv;
-	int i = 0;
-
-	do {
-		if ((psecuritypriv->PMKIDList[i].bUsed) &&
-		    (!memcmp(psecuritypriv->PMKIDList[i].Bssid, bssid, ETH_ALEN))) {
-			break;
-		} else {
-			i++;
-			/* continue; */
-		}
-
-	} while (i < NUM_PMKID_CACHE);
+	struct security_priv *p = &Adapter->securitypriv;
+	int i;
 
-	if (i == NUM_PMKID_CACHE) {
-		i = -1;/*  Could not find. */
-	} else {
-		/*  There is one Pre-Authentication Key for the specific BSSID. */
-	}
-	return i;
+	for (i = 0; i < NUM_PMKID_CACHE; i++)
+		if ((p->PMKIDList[i].bUsed) &&
+				(!memcmp(p->PMKIDList[i].Bssid, bssid, ETH_ALEN)))
+			return i;
+	return -1;
 }
 
 /*  */

Signature · 1 line

2.25.1

Pavel Skripkin

2022-04-03 15:59 UTC #1 lore raw

Hi Sevinj,

Quoted 8 lines · Sevinj Aghayeva

The function iterates an index from 0 to NUM_PMKID_CACHE and returns the first index for which the condition is true. If no such index is found, the function returns -1. Current code has a complex control flow that obfuscates this simple task. Replace it with a loop.
Also, given the shortened function body, replace the long variable name psecuritypriv with a short variable name p.

Quoted 6 lines

Reported by checkpatch:
WARNING: else is not generally useful after a break or return
Signed-off-by Sevinj Aghayeva <[email protected]>
---

[code snip]

drivers/staging/r8188eu/core/rtw_mlme.c int rtw_restruct_wmm_ie(struct adapter *adapter, u8 *in_ie, u8 *out_ie, uint in_ · line 1650

Quoted 8 lines

drivers/staging/r8188eu/core/rtw_mlme.c +5 -0

+	for (i = 0; i < NUM_PMKID_CACHE; i++)
+		if ((p->PMKIDList[i].bUsed) &&
+				(!memcmp(p->PMKIDList[i].Bssid, bssid, ETH_ALEN)))
+			return i;
+	return -1;
  }
 
  /*  */

Looks good, but let's not introduce new checkpatch issue:

CHECK: Alignment should match open parenthesis #62: FILE: drivers/staging/r8188eu/core/rtw_mlme.c:1645:
+ if ((p->PMKIDList[i].bUsed) &&
+ (!memcmp(p->PMKIDList[i].Bssid, bssid, ETH_ALEN)))

With regards,
Pavel Skripkin

Sevinj Aghayeva

author

2022-04-03 16:12 UTC #2 lore raw

Hi Pavel,

Quoted 34 lines · Pavel Skripkin

Hi Sevinj,
Quoted 8 lines · Sevinj Aghayeva
The function iterates an index from 0 to NUM_PMKID_CACHE and returns the first index for which the condition is true. If no such index is found, the function returns -1. Current code has a complex control flow that obfuscates this simple task. Replace it with a loop.
Also, given the shortened function body, replace the long variable name psecuritypriv with a short variable name p.
Quoted 6 lines
Reported by checkpatch:
WARNING: else is not generally useful after a break or return
Signed-off-by Sevinj Aghayeva <[email protected]>
---
[code snip]
drivers/staging/r8188eu/core/rtw_mlme.c int rtw_restruct_wmm_ie(struct adapter *adapter, u8 *in_ie, u8 *out_ie, uint in_ · line 1650
Quoted 8 lines
drivers/staging/r8188eu/core/rtw_mlme.c +5 -0
+     for (i = 0; i < NUM_PMKID_CACHE; i++)
+             if ((p->PMKIDList[i].bUsed) &&
+                             (!memcmp(p->PMKIDList[i].Bssid, bssid, ETH_ALEN)))
+                     return i;
+     return -1;
  }
 
  /*  */
Looks good, but let's not introduce new checkpatch issue:
CHECK: Alignment should match open parenthesis #62: FILE: drivers/staging/r8188eu/core/rtw_mlme.c:1645:

drivers/staging/r8188eu/core/rtw_mlme.c int rtw_restruct_wmm_ie(struct adapter *adapter, u8 *in_ie, u8 *out_ie, uint in_ · line 1645

Quoted 2 lines

drivers/staging/r8188eu/core/rtw_mlme.c +2 -0

+               if ((p->PMKIDList[i].bUsed) &&
+                               (!memcmp(p->PMKIDList[i].Bssid, bssid, ETH_ALEN)))

Thanks for catching this. I wasn't seeing this in my checkpatch output, and after some digging, I could reproduce it with --strict option. I think the tutorial at
https://kernelnewbies.org/PatchPhilosophy doesn't mention this option, so perhaps we should update it?!

Quoted 6 lines

With regards,
Pavel Skripkin

Signature · 1 line

Sevinj.Aghayeva

Pavel Skripkin

2022-04-03 16:16 UTC #3 lore raw

Hi Sevinj,

Quoted 8 lines · Sevinj Aghayeva

drivers/staging/r8188eu/core/rtw_mlme.c int rtw_restruct_wmm_ie(struct adapter *adapter, u8 *in_ie, u8 *out_ie, uint in_ · line 1645
Quoted 7 lines
Looks good, but let's not introduce new checkpatch issue:
CHECK: Alignment should match open parenthesis #62: FILE: drivers/staging/r8188eu/core/rtw_mlme.c:1645:
drivers/staging/r8188eu/core/rtw_mlme.c +2 -0
+               if ((p->PMKIDList[i].bUsed) &&
+                               (!memcmp(p->PMKIDList[i].Bssid, bssid, ETH_ALEN)))

Quoted 6 lines

Thanks for catching this. I wasn't seeing this in my checkpatch output, and after some digging, I could reproduce it with --strict option. I think the tutorial at
https://kernelnewbies.org/PatchPhilosophy doesn't mention this option, so perhaps we should update it?!

To be honest, I am not checkpatch expert, but checkpatch on my PC shows this warning w/o any additional options:

└──$ ./scripts/checkpatch.pl ./20220403_sevinj_aghayeva_staging_r8188eu_simplify_control_flow.mbx | rg Alignment
CHECK: Alignment should match open parenthesis

With regards,
Pavel Skripkin

Sevinj Aghayeva

author

2022-04-03 16:29 UTC #4 lore raw

Quoted 19 lines · Pavel Skripkin

Hi Sevinj,
Quoted 8 lines · Sevinj Aghayeva
drivers/staging/r8188eu/core/rtw_mlme.c int rtw_restruct_wmm_ie(struct adapter *adapter, u8 *in_ie, u8 *out_ie, uint in_ · line 1645
Quoted 7 lines
Looks good, but let's not introduce new checkpatch issue:
CHECK: Alignment should match open parenthesis #62: FILE: drivers/staging/r8188eu/core/rtw_mlme.c:1645:
drivers/staging/r8188eu/core/rtw_mlme.c +2 -0
+               if ((p->PMKIDList[i].bUsed) &&
+                               (!memcmp(p->PMKIDList[i].Bssid, bssid, ETH_ALEN)))
Quoted 6 lines
Thanks for catching this. I wasn't seeing this in my checkpatch output, and after some digging, I could reproduce it with --strict option. I think the tutorial at
https://kernelnewbies.org/PatchPhilosophy doesn't mention this option, so perhaps we should update it?!

Quoted 7 lines

To be honest, I am not checkpatch expert, but checkpatch on my PC shows this warning w/o any additional options:
└──$ ./scripts/checkpatch.pl
./20220403_sevinj_aghayeva_staging_r8188eu_simplify_control_flow.mbx |
rg Alignment
CHECK: Alignment should match open parenthesis

Ah, I see. You run it on an email file that contains the patch. I could reproduce what you saw when I ran checkpatch without any options on an email file. But my usual workflow is to modify a file, e.g. rtw_mlme.c and then run "checkpatch.pl -f rtw_mlme.c", in which case I cannot see the "Alignment should match" error. So it looks like if you do not specify -f then checkpatch.pl enables --strict option.

Quoted 7 lines

With regards,
Pavel Skripkin

Signature · 1 line

Sevinj.Aghayeva

Michael Straube

2022-04-03 16:43 UTC #5 lore raw

Quoted 7 lines · Sevinj Aghayeva

Ah, I see. You run it on an email file that contains the patch. I could reproduce what you saw when I ran checkpatch without any options on an email file. But my usual workflow is to modify a file, e.g. rtw_mlme.c and then run "checkpatch.pl -f rtw_mlme.c", in which case I cannot see the "Alignment should match" error. So it looks like if you do not specify -f then checkpatch.pl enables --strict option.

Hi Sevinj,

I'm also not a checkpatch expert, but on my system this works without --strict too. I applied your patch to my local tree and get:

/scripts/checkpatch.pl -f drivers/staging/r8188eu/core/rtw_mlme.c

[snip]

CHECK: Alignment should match open parenthesis #1638: FILE: drivers/staging/r8188eu/core/rtw_mlme.c:1638:
+ if ((p->PMKIDList[i].bUsed) &&
+ (!memcmp(p->PMKIDList[i].Bssid, bssid, ETH_ALEN)))

[snip]

You can also run checkpatch on the patch files (without -f). Then it's easier to see if you introduced new issues.

regards,
Michael

Sevinj Aghayeva

author

2022-04-03 17:00 UTC #6 lore raw

Quoted 10 lines · Michael Straube

Quoted 7 lines · Sevinj Aghayeva
Ah, I see. You run it on an email file that contains the patch. I could reproduce what you saw when I ran checkpatch without any options on an email file. But my usual workflow is to modify a file, e.g. rtw_mlme.c and then run "checkpatch.pl -f rtw_mlme.c", in which case I cannot see the "Alignment should match" error. So it looks like if you do not specify -f then checkpatch.pl enables --strict option.

Quoted 6 lines

Hi Sevinj,
I'm also not a checkpatch expert, but on my system this works without --strict too. I applied your patch to my local tree and get:
/scripts/checkpatch.pl -f drivers/staging/r8188eu/core/rtw_mlme.c

Hi Michael,

That's odd. I don't get any CHECK messages if I run exactly the same command as above:

$ pwd
/home/sevinj/k/staging/drivers/staging/r8188eu/core
$ ~/k/staging/scripts/checkpatch.pl -f rtw_mlme.c | grep 'CHECK:' | wc -l
0

I have to specify --strict to get CHECK messages:

$ ~/k/staging/scripts/checkpatch.pl --strict -f rtw_mlme.c | grep
'CHECK:' | wc -l
167

I don't know why that is. I'm on Ubuntu 20.04 and it looks like I'm running checkpatch version 0.32:

$ ~/k/staging/scripts/checkpatch.pl -h
Usage: /home/sevinj/k/staging/scripts/checkpatch.pl [OPTION]... [FILE]...
Version: 0.32

<snip>

Quoted 16 lines

[snip]
CHECK: Alignment should match open parenthesis #1638: FILE: drivers/staging/r8188eu/core/rtw_mlme.c:1638:
(quoted diff) +2 -0
+               if ((p->PMKIDList[i].bUsed) &&
+                               (!memcmp(p->PMKIDList[i].Bssid, bssid,
ETH_ALEN)))
[snip]
You can also run checkpatch on the patch files (without -f). Then it's easier to see if you introduced new issues.
regards,
Michael

Signature · 1 line

Sevinj.Aghayeva