Re: [PATCH] stm: the number of masters should be (sw_end - sw_start + 1)

[Alexander Shishkin <alexander.shishkin@linux.intel.com>]

Chunyan Zhang <zhang.chunyan@linaro.org> writes:

> sw_end represents the last software master, sw_start is index of the
> first master, so the number of software masters should be
> sw_end - sw_start + 1.

Looks about right, but it needs to be in two separate patches.

> Signed-off-by: Chunyan Zhang <zhang.chunyan@linaro.org>
> ---
>  drivers/hwtracing/intel_th/sth.c | 2 +-
>  drivers/hwtracing/stm/core.c     | 2 +-
>  2 files changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/hwtracing/intel_th/sth.c b/drivers/hwtracing/intel_th/sth.c
> index 56101c3..28917d7 100644
> --- a/drivers/hwtracing/intel_th/sth.c
> +++ b/drivers/hwtracing/intel_th/sth.c
> @@ -173,7 +173,7 @@ static int intel_th_sw_init(struct sth_device *sth)
>  	sth->stm.sw_start = reg & 0xffff;
>  	sth->stm.sw_end = reg >> 16;
>  
> -	sth->sw_nmasters = sth->stm.sw_end - sth->stm.sw_start;
> +	sth->sw_nmasters = sth->stm.sw_end - sth->stm.sw_start + 1;
>  	dev_dbg(sth->dev, "sw_start: %x sw_end: %x masters: %x nchannels: %x\n",
>  		sth->stm.sw_start, sth->stm.sw_end, sth->sw_nmasters,
>  		sth->stm.sw_nchannels);
> diff --git a/drivers/hwtracing/stm/core.c b/drivers/hwtracing/stm/core.c
> index 7f7bdb3..cb676f2 100644
> --- a/drivers/hwtracing/stm/core.c
> +++ b/drivers/hwtracing/stm/core.c
> @@ -632,7 +632,7 @@ int stm_register_device(struct device *parent, struct stm_data *stm_data,
>  	if (!stm_data->packet || !stm_data->sw_nchannels)
>  		return -EINVAL;
>  
> -	nmasters = stm_data->sw_end - stm_data->sw_start;
> +	nmasters = stm_data->sw_end - stm_data->sw_start + 1;
>  	stm = kzalloc(sizeof(*stm) + nmasters * sizeof(void *), GFP_KERNEL);

Or even offsetof(struct stm_device, masters[stm_data->sw_end]).

>  	if (!stm)
>  		return -ENOMEM;
> -- 
> 1.9.1

This is a very old version on git, btw. :)

Thanks,
--
Alex