Messages in this thread | | | Date | Fri, 18 Aug 2023 23:23:01 +0900 | From | Masami Hiramatsu (Google) <> | Subject | Re: [PATCH v2] tracing: Introduce pipe_cpumask to avoid race on trace_pipes |
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On Fri, 18 Aug 2023 09:41:28 -0400 Steven Rostedt <rostedt@goodmis.org> wrote:
> On Fri, 18 Aug 2023 14:03:09 +0900 > Masami Hiramatsu (Google) <mhiramat@kernel.org> wrote: > > > Looks good to me. > > > > Reviewed-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> > > > > BTW, this reminds me that splice read support had been introduced for > > virtio-trace support. I've tested it with/without this patch, but I hit > > a different issue, which seems like a virtio-serial issue (per-cpu buffers > > on the guest are spliced correctly, but the data can not be read from host > > side). Let me investigate it. > > Is virtio-trace using trace_pipe or trace_pipe_raw? Those two are handled > differently.
It uses trace_pipe_raw. I guess if splice(from trace_pipe_raw to virtio-serial) returns -1 and errno == EAGAIN, the trace data will be lost?
Thank you,
> > -- Steve
-- Masami Hiramatsu (Google) <mhiramat@kernel.org>
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