Re: [RFC PATCH v2] posix timers: allocate timer id per task

From: Stanislav Kinsbursky
Date: Wed Oct 17 2012 - 10:19:57 EST

17.10.2012 17:44, Eric Dumazet ÐÐÑÐÑ:
On Wed, 2012-10-17 at 17:18 +0400, Stanislav Kinsbursky wrote:

+static int hash(struct signal_struct *sig, unsigned int nr)
+ int hash = hash_ptr(sig, POSIX_TIMERS_HASH_BITS);
+ return hash ^ hash_32(nr, POSIX_TIMERS_HASH_BITS);

This is quite expensive on 64 bit arches. I suggest instead :

return hash_32(hash32_ptr(sig) ^ nr, POSIX_TIMERS_HASH_BITS);

I'm not familiar with hashing costs, so sure, I'll update.

Best regards,
Stanislav Kinsbursky
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