2019-09-25 17:42:48

by Valentin Schneider

Subject: [PATCH v2 5/9] microblaze: entry: Remove unneeded need_resched() loop

Since the enabling and disabling of IRQs within preempt_schedule_irq()
is contained in a need_resched() loop, we don't need the outer arch
code loop.

Signed-off-by: Valentin Schneider <[email protected]>
Cc: Michal Simek <[email protected]>
---
arch/microblaze/kernel/entry.S | 5 -----
1 file changed, 5 deletions(-)

diff --git a/arch/microblaze/kernel/entry.S b/arch/microblaze/kernel/entry.S
index 4e1b567becd6..de7083bd1d24 100644
--- a/arch/microblaze/kernel/entry.S
+++ b/arch/microblaze/kernel/entry.S
@@ -738,14 +738,9 @@ no_intr_resched:
andi r5, r5, _TIF_NEED_RESCHED;
beqi r5, restore /* if zero jump over */

-preempt:
/* interrupts are off that's why I am calling preempt_chedule_irq */
bralid r15, preempt_schedule_irq
nop
- lwi r11, CURRENT_TASK, TS_THREAD_INFO; /* get thread info */
- lwi r5, r11, TI_FLAGS; /* get flags in thread info */
- andi r5, r5, _TIF_NEED_RESCHED;
- bnei r5, preempt /* if non zero jump to resched */
restore:
#endif
VM_OFF /* MS: turn off MMU */
--
2.22.0

2019-09-26 01:15:06

by Michal Simek

Subject: Re: [PATCH v2 5/9] microblaze: entry: Remove unneeded need_resched() loop

On 23. 09. 19 16:36, Valentin Schneider wrote:
> Since the enabling and disabling of IRQs within preempt_schedule_irq()
> is contained in a need_resched() loop, we don't need the outer arch
> code loop.
>
> Signed-off-by: Valentin Schneider <[email protected]>
> Cc: Michal Simek <[email protected]>
> ---
> arch/microblaze/kernel/entry.S | 5 -----
> 1 file changed, 5 deletions(-)
>
> diff --git a/arch/microblaze/kernel/entry.S b/arch/microblaze/kernel/entry.S
> index 4e1b567becd6..de7083bd1d24 100644
> --- a/arch/microblaze/kernel/entry.S
> +++ b/arch/microblaze/kernel/entry.S
> @@ -738,14 +738,9 @@ no_intr_resched:
> andi r5, r5, _TIF_NEED_RESCHED;
> beqi r5, restore /* if zero jump over */
>
> -preempt:
> /* interrupts are off that's why I am calling preempt_chedule_irq */
> bralid r15, preempt_schedule_irq
> nop
> - lwi r11, CURRENT_TASK, TS_THREAD_INFO; /* get thread info */
> - lwi r5, r11, TI_FLAGS; /* get flags in thread info */
> - andi r5, r5, _TIF_NEED_RESCHED;
> - bnei r5, preempt /* if non zero jump to resched */
> restore:
> #endif
> VM_OFF /* MS: turn off MMU */
>

Looks reasonable and also tested on HW. I expect you want me to take it
via microblaze tree that's why applied.

Thanks,
Michal

--
Michal Simek, Ing. (M.Eng), OpenPGP -> KeyID: FE3D1F91
w: http://www.monstr.eu p: +42-0-721842854
Maintainer of Linux kernel - Xilinx Microblaze
Maintainer of Linux kernel - Xilinx Zynq ARM and ZynqMP ARM64 SoCs
U-Boot custodian - Xilinx Microblaze/Zynq/ZynqMP/Versal SoCs

2019-09-26 01:21:38

by Valentin Schneider

Subject: Re: [PATCH v2 5/9] microblaze: entry: Remove unneeded need_resched() loop

On 24/09/2019 11:30, Michal Simek wrote:
> On 23. 09. 19 16:36, Valentin Schneider wrote:
>> Since the enabling and disabling of IRQs within preempt_schedule_irq()
>> is contained in a need_resched() loop, we don't need the outer arch
>> code loop.
>>
>> Signed-off-by: Valentin Schneider <[email protected]>
>> Cc: Michal Simek <[email protected]>
>> ---
>> arch/microblaze/kernel/entry.S | 5 -----
>> 1 file changed, 5 deletions(-)
>>
>> diff --git a/arch/microblaze/kernel/entry.S b/arch/microblaze/kernel/entry.S
>> index 4e1b567becd6..de7083bd1d24 100644
>> --- a/arch/microblaze/kernel/entry.S
>> +++ b/arch/microblaze/kernel/entry.S
>> @@ -738,14 +738,9 @@ no_intr_resched:
>> andi r5, r5, _TIF_NEED_RESCHED;
>> beqi r5, restore /* if zero jump over */
>>
>> -preempt:
>> /* interrupts are off that's why I am calling preempt_chedule_irq */
>> bralid r15, preempt_schedule_irq
>> nop
>> - lwi r11, CURRENT_TASK, TS_THREAD_INFO; /* get thread info */
>> - lwi r5, r11, TI_FLAGS; /* get flags in thread info */
>> - andi r5, r5, _TIF_NEED_RESCHED;
>> - bnei r5, preempt /* if non zero jump to resched */
>> restore:
>> #endif
>> VM_OFF /* MS: turn off MMU */
>>
>
> Looks reasonable and also tested on HW. I expect you want me to take it
> via microblaze tree that's why applied.
>

Yes, please. Thanks!

> Thanks,
> Michal
>