Re: [PATCH v2] net: bluetooth: hci_sock: Use 'const void *' instead of 'void *' for 2nd parameter of hci_test_bit()

From: Sergei Shtylyov
Date: Wed Feb 04 2015 - 15:13:40 EST


Hello.

On 02/04/2015 02:59 PM, David Laight wrote:

-static inline int hci_test_bit(int nr, void *addr)
+static inline int hci_test_bit(int nr, const void *addr)
{
return *((__u32 *) addr + (nr >> 5)) & ((__u32) 1 << (nr & 31));
}

Is there a 'standard' function lurking that will do the above.
On x86 the cpus 'bit test' instruction will handle bit numbers
greater than the word size - so it can be a single instruction.

Of course, there's test_bit().

David

WBR, Sergei

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