Re: [PATCH with SmPL?] staging: rtl8188eu: Adjustments around jump labels

From: SF Markus Elfring
Date: Wed Nov 12 2014 - 05:52:16 EST


>>>> @@ -212,8 +212,7 @@ efuse_phymap_to_logical(u8 *phymap, u16 _offset, u16
>>>> _size_byte, u8 *pbuf)
>>>> exit:
>>>> kfree(efuseTbl);
>>>>
>>>> - if (eFuseWord)
>>>> - kfree(eFuseWord);
>>>> + kfree(eFuseWord);
>>>
>>> I think that this code has been updated already. It would be better to
>>> add labels so that kfree is only executed when needed.
>>
>> Are there any chances to achieve the suggested fine-tuning for jump labels
>> also with another semantic patch approach?
>
> No, I don't think so. The pattern is not regular enough.

Now I have got a different impression for corresponding improvement possibilities.


elfring@Sonne:~/Projekte/Linux/stable-patched> spatch.opt -debug -sp-file ~/Projekte/Coccinelle/janitor/move_function_call_before_jump_label1.cocci drivers/staging/rtl8188eu/core/rtw_efuse.c
init_defs_builtins: /usr/local/share/coccinelle/standard.h
-----------------------------------------------------------------------
processing semantic patch file: /home/elfring/Projekte/Coccinelle/janitor/move_function_call_before_jump_label1.cocci
with isos from: /usr/local/share/coccinelle/standard.iso
-----------------------------------------------------------------------
@move_function_call_before_jump_label@
expression x;
identifier fu, label;
type t;
@@
t fu(...)
{
... when any
x = kzalloc(...);
if (x == NULL) {
...
goto label;
}
... when any
+ kfree(x);
label:
- kfree(x);
...
}

HANDLING: drivers/staging/rtl8188eu/core/rtw_efuse.c
-----------------------------------------------------------------------
let's go
-----------------------------------------------------------------------
-----------------------------------------------------------------------
-----------------------------------------------------------------------
move_function_call_before_jump_label =
-----------------------------------------------------------------------
dependencies for rule move_function_call_before_jump_label satisfied:
binding in = []
binding relevant in = []
(ONCE) USING optional_storage builtin isomorphism
transformation info returned:
transform state: 5
with rule_elem:
<<< kfree(move_function_call_before_jump_label:x);
move_function_call_before_jump_label:label:
with binding: [move_function_call_before_jump_label.x --> efuseTbl]
transform state: 204
with rule_elem: -kfree-(-move_function_call_before_jump_label:x-)-;
with binding: [move_function_call_before_jump_label.x --> efuseTbl]
binding out = []
transform one node: 204
transform one node: 5
-----------------------------------------------------------------------
Finished
-----------------------------------------------------------------------
diff =
--- drivers/staging/rtl8188eu/core/rtw_efuse.c
+++ /tmp/cocci-output-4498-349827-rtw_efuse.c
@@ -209,8 +209,8 @@ efuse_phymap_to_logical(u8 *phymap, u16
/* 5. Calculate Efuse utilization. */
/* */

+kfree(efuseTbl);
exit:
- kfree(efuseTbl);

kfree(eFuseWord);
}
Check duplication for 1 files



Can my update suggestion be generalised a bit more for the movement of specific jump labels
towards the end of a function implementation like in the use case "efuse_phymap_to_logical()"?

Regards,
Markus
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