Re: [PATCH 1/2] perf_event_open.2: Document PERF_EVENT_IOC_PAUSE_OUTPUT

From: Vince Weaver
Date: Fri Oct 21 2016 - 17:16:36 EST


On Fri, 21 Oct 2016, Wang Nan wrote:


> -.SS Using prctl(2)
> +.SS Using prctl

why this change?

> +.BR PERF_EVENT_IOC_PAUSE_OUTPUT " (since Linux 4.7)"
> +.\" commit 86e7972f690c1017fd086cdfe53d8524e68c661c
> +This allows pausing and resuming the event's ring-buffer. A
> +paused ring-buffer does not prevent samples generation, but simply
> +discards them. The discarded samples are considered lost, causes
> +.BR PERF_RECORD_LOST
> +to be generated when possible.

I don't know if it's worth mentioning that the reason to add this is to
allow reading the ring-buffer without having to worry about data being
overwritten.

There are a few odd wording choices (mostly plural nouns) but otherwise
looks fine to me.

Reviewed-by: Vince Weaver <vincent.weaver@xxxxxxxxx>