Re: [PATCH RT 3/3 - take two ] fix get_monotonic_cycles for latency tracer

From: Frank Ch. Eigler
Date: Sat Aug 25 2007 - 07:07:59 EST



Steven Rostedt <rostedt@xxxxxxxxxxx> writes:

> [...]
> + * [...] We don't need to grab
> + * any locks, we just keep trying until get all the
> + * calculations together in one state.
> + *
> + * In fact, we __cant__ grab any locks. This
> + * function is called from the latency_tracer which can
> + * be called anywhere. To grab any locks (including
> + * seq_locks) we risk putting ourselves into a deadlock.

Perhaps you could add a comment about why the loop, which appears
potentially infinite as written, avoids livelock. (It looks rather
like a seqlock read loop.)

- FChE
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