Re: coding for optimizations (Re: [PATCH 1/2] i386: mce cleanup part1: functional change)

Joerg Roedel
2007-10-09T18:31:25Z

On Tue, Oct 09, 2007 at 07:33:17PM +0200, olecom@flower.upol.cz wrote:
> if (!mce_disabled) {
> if (!(c->x86_capability & (X86_FEATURE_MCA | X86_FEATURE_MCE)) {
> printk(KERN_INFO "CPU%i: No machine check support available\n",
> smp_processor_id());
> return;
> }
> /* function code */
> }

I have 2 problems with this way:

1) It is totally broken because c->x86_capability is not an integer but
an *array* of integers. This is also the reason why test_bit() is used
in cpu_has() and not plain logical operators.

2) It is still hard to read and breaks the kernel coding style.

But you are right with the redundant mca and mce variables. They are not
needed and I will inline the cpu_has() checks into the condition check.
I'll resubmit tomorrow.

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