Re: [RFC -tip] x86: introduce ENTRY(KPROBE)_X86 assembly helpersto catch unbalanced declaration

From: Cyrill Gorcunov
Date: Sun Nov 23 2008 - 12:58:58 EST


[Sam Ravnborg - Sun, Nov 23, 2008 at 06:51:25PM +0100]
| On Sun, Nov 23, 2008 at 07:57:11PM +0300, Cyrill Gorcunov wrote:
| > It's usefull to catch unbalanced, missed or mixed declarations of ENTRY and
| > KPROBES. These macros would help a bit (at least I hope so).
| >
| > For example the following code would compile without problems
| >
| > ENTRY_X86(mcount)
| > retq
| > END_X86(mcount)
| >
| > But if you forget and mix the following form
| >
| > ENTRY_X86(mcount)
| > retq
| > END(mcount)
| >
| > ENTRY_X86(ftrace_caller)
| >
| > The assembler will issue the following message:
| > Error: ENTRY_X86/KPROBE_X86 unbalanced,missed,mixed
| >
| > Actually the checking is performed at every _X86 macro
| > so maybe it's good idea to put ENTRY_KPROBE_FINAL_X86
| > at the end of .S file to be sure you didn't miss anything.
|
| Could we at least try this out in -next before we decide to make
| this X86 only?
| I am aware that binutils can be a bit fragile but -next testing should
| make a good check on this.
|
| Sam
|

I don't have -next tree on my laptop, neither cross-compile tools but
if someone could test it -- it would be great. But I used gas macros
here -- i doubt other architectures has the same syntax. At least
PDP-11 would beat us with ';' symbol :)

- Cyrill -
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/