Change behaviour when tracing ... nasty trap (was Re: [PATCH] PM/Trace: get rid of synchronous resume limit during PM trace)

Pavel Machek
2015-01-26T10:23:59Z

On Mon 2015-01-26 13:07:03, Fu, Zhonghui wrote:
> >From f9c841d1f943d81b5ab0aac7483e794a7f966296 Mon Sep 17 00:00:00 2001
> From: Zhonghui Fu <zhonghui.fu@linux.intel.com>
> Date: Mon, 26 Jan 2015 11:27:08 +0800
> Subject: [PATCH] PM/Trace: get rid of synchronous resume limit during PM trace
>
> There are some kind of dependency between devices in some
> hardware platforms. So, asynchronous resuming devices may
> hang system due to wrong resume order. As a result, should
> not fore synchronously resuming devices during tracing
> PM events.
>
> Signed-off-by: Zhonghui Fu <zhonghui.fu@linux.intel.com>
> ---
> drivers/base/power/main.c | 3 +--
> include/linux/resume-trace.h | 7 -------
> 2 files changed, 1 insertions(+), 9 deletions(-)
>
> diff --git a/drivers/base/power/main.c b/drivers/base/power/main.c
> index 9717d5f..5df148b 100644
> --- a/drivers/base/power/main.c
> +++ b/drivers/base/power/main.c
> @@ -517,8 +517,7 @@ static int device_resume_noirq(struct device *dev, pm_message_t state, bool asyn
>
> static bool is_async(struct device *dev)
> {
> - return dev->power.async_suspend && pm_async_enabled
> - && !pm_trace_is_enabled();
> + return dev->power.async_suspend && pm_async_enabled;
> }
>

Actually... whoever did the original patch was evil person. Changing
behaviour when tracing is requested is evil, evil, evil. Git blame
tells me

Signed-off-by: Chuansheng Liu <chuansheng.liu@intel.com>

went to the dark side.

Pavel

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