Eirik Nygaard wrote:
Hi...
I am just wondering what the atomic_* functions in machine/atmoic.h does.
I have read the assembly code and more or less understood it, but I still
don't see the need for it. So if anyone would enlighten me that would be
great.
Think about parallel threads of execution (threads or a kernel with SMP). If
the thread gets interrupted in the middle of non-atomic operation (say, an
int is incremented via a temporary register), then the result of the
operation (the value of that integer) cannot be reliably addressed in the
other thread. These functions in machine/atomic.h help you to perform
certain functions uninterrupted, possibly via a single assembly instruction,
hence the "atomic" prefix.
--
Lev Walkin
[EMAIL PROTECTED]
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