Re: [PATCH 3/4] perf/x86/cqm: One check and another variable less in intel_mbm_init()

From: Peter Zijlstra
Date: Mon Sep 05 2016 - 03:54:30 EST


On Sun, Sep 04, 2016 at 07:58:32PM +0200, SF Markus Elfring wrote:
> From: Markus Elfring <elfring@xxxxxxxxxxxxxxxxxxxxx>
> Date: Sun, 4 Sep 2016 19:06:33 +0200
>
> 1. Adjust a jump target to eliminate an extra check at the end.
>
> 2. Move a jump label according to the current Linux coding style convention.

WTF does that even mean?

>
> 3. Return only constant values for the success or failure indication.
>
> 4. Delete the local variable "ret" which became unnecessary with
> this refactoring.

Also, 4 things should be 4 patches if anything.

>
> Signed-off-by: Markus Elfring <elfring@xxxxxxxxxxxxxxxxxxxxx>
> ---
> arch/x86/events/intel/cqm.c | 25 ++++++++++---------------
> 1 file changed, 10 insertions(+), 15 deletions(-)
>
> diff --git a/arch/x86/events/intel/cqm.c b/arch/x86/events/intel/cqm.c
> index 29f756e..304caf53 100644
> --- a/arch/x86/events/intel/cqm.c
> +++ b/arch/x86/events/intel/cqm.c
> @@ -1637,7 +1637,7 @@ static const struct x86_cpu_id intel_mbm_total_match[] = {
>
> static int intel_mbm_init(void)
> {
> - int ret = 0, maxid = cqm_max_rmid + 1;
> + int const maxid = cqm_max_rmid + 1;
>
> mbm_socket_max = topology_max_packages();
> mbm_local = kmalloc_array(maxid * mbm_socket_max,
> @@ -1649,25 +1649,20 @@ static int intel_mbm_init(void)
> mbm_total = kmalloc_array(maxid * mbm_socket_max,
> sizeof(*mbm_total),
> GFP_KERNEL);
> - if (!mbm_total) {
> - ret = -ENOMEM;
> - goto out;
> - }
> + if (!mbm_total)
> + goto free_mbm;
>
> mbm_timers = kmalloc_array(mbm_socket_max,
> sizeof(*mbm_timers),
> GFP_KERNEL);
> - if (!mbm_timers) {
> - ret = -ENOMEM;
> - goto out;
> - }
> - mbm_hrtimer_init();
> + if (!mbm_timers)
> + goto free_mbm;
>
> -out:
> - if (ret)
> - mbm_cleanup();
> -
> - return ret;
> + mbm_hrtimer_init();
> + return 0;
> + free_mbm:

No!! no stupid indented labels.

> + mbm_cleanup();
> + return -ENOMEM;
> }