diff mbox

[v2,07/11] ARC: [plat-eznps] disabled stall counter due to a HW bug

Message ID 1495954328-28736-8-git-send-email-noamca@mellanox.com
State New
Headers show

Commit Message

Noam Camus May 28, 2017, 6:52 a.m. UTC
From: Noam Camus <noamca@mellanox.com>

This counter represents threshold for consecutive stall that which
trigger HW threads scheduling.
When this feature is enabled low values of this counter cause
downgrade in performance and in the worst case even a livelock.

Remove those couple of lines and resort to HW reset value i.e.
this feature is disabled (.sten field equals 0).

Signed-off-by: Noam Camus <noamca@mellanox.com>
---
 arch/arc/plat-eznps/mtm.c |    2 --
 1 files changed, 0 insertions(+), 2 deletions(-)

Comments

Alexey Brodkin May 29, 2017, 3:15 p.m. UTC | #1
Hi Noam,

On Sun, 2017-05-28 at 09:52 +0300, Noam Camus wrote:
> From: Noam Camus <noamca@mellanox.com>

> 

> This counter represents threshold for consecutive stall that which

> trigger HW threads scheduling.

> When this feature is enabled low values of this counter cause

> downgrade in performance and in the worst case even a livelock.

> 

> Remove those couple of lines and resort to HW reset value i.e.

> this feature is disabled (.sten field equals 0).


Looks like you made a change I was asking for here.
But there's no mention of the change so it's easy to not note
that change. Not critical but please add a changelog next time 
even if it's only a comment message that was modified since
the previous revision.

Otherwise...

Reviewed-by: Alexey Brodkin <abrodkin@synopsys.com>


> Signed-off-by: Noam Camus <noamca@mellanox.com>

> ---

>  arch/arc/plat-eznps/mtm.c |    2 --

>  1 files changed, 0 insertions(+), 2 deletions(-)

> 

> diff --git a/arch/arc/plat-eznps/mtm.c b/arch/arc/plat-eznps/mtm.c

> index aaaaffd..e0cb36b 100644

> --- a/arch/arc/plat-eznps/mtm.c

> +++ b/arch/arc/plat-eznps/mtm.c

> @@ -119,8 +119,6 @@ void mtm_enable_core(unsigned int cpu)

>  	mt_ctrl.value = 0;

>  	mt_ctrl.hsen = 1;

>  	mt_ctrl.hs_cnt = MT_CTRL_HS_CNT;

> -	mt_ctrl.sten = 1;

> -	mt_ctrl.st_cnt = MT_CTRL_ST_CNT;

>  	mt_ctrl.mten = 1;

>  	write_aux_reg(CTOP_AUX_MT_CTRL, mt_ctrl.value);

>
diff mbox

Patch

diff --git a/arch/arc/plat-eznps/mtm.c b/arch/arc/plat-eznps/mtm.c
index aaaaffd..e0cb36b 100644
--- a/arch/arc/plat-eznps/mtm.c
+++ b/arch/arc/plat-eznps/mtm.c
@@ -119,8 +119,6 @@  void mtm_enable_core(unsigned int cpu)
 	mt_ctrl.value = 0;
 	mt_ctrl.hsen = 1;
 	mt_ctrl.hs_cnt = MT_CTRL_HS_CNT;
-	mt_ctrl.sten = 1;
-	mt_ctrl.st_cnt = MT_CTRL_ST_CNT;
 	mt_ctrl.mten = 1;
 	write_aux_reg(CTOP_AUX_MT_CTRL, mt_ctrl.value);