Re: [libvirt] [RFC] Atomic Operations
On Wed, Jun 04, 2014 at 08:16:16AM -0400, Tucker DiNapoli wrote:
I'm working on job control which involves a lot of locking and
unlocking,
often for operations that could be done atomically. I use the existing
atomic integer operations in viratomic.h where possible, but there are a
lot of parameters involved in jobs (such as time, thread id's, progress
information, etc) which don't fit in an integer.
If there are many different data items which need updating then I'd
really think this is better done with mutexes. I wouldn't even assume
that atomic ops are neccessarily going to be faster. When I optimized
our logging routines recently I tried to make use of atomic ops for
a bunch of variables but found it was actually quicker to use mutexes
since one mutex lock can protect many variable writes, whereas every
atomic op read/write has a cost.
Regards,
Daniel
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