[Intel-gfx] [CI 2/2] drm/i915/perf: reuse intel_lrc ctx regs macro

[Chris Wilson]

Quoting Tvrtko Ursulin (2018-08-14 19:49:46)
> 
> On 13/08/2018 10:16, Chris Wilson wrote:
> > Quoting Tvrtko Ursulin (2018-08-13 10:11:44)
> >>
> >> On 13/08/2018 09:16, Chris Wilson wrote:
> >>> Quoting Tvrtko Ursulin (2018-08-13 09:02:18)
> >>>> From: Lionel Landwerlin <lionel.g.landwerlin at intel.com>
> >>>>
> >>>> Abstract the context image access a bit.
> >>>>
> >>>> Signed-off-by: Lionel Landwerlin <lionel.g.landwerlin at intel.com>
> >>>> Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin at intel.com>
> >>>> ---
> >>>>    drivers/gpu/drm/i915/i915_perf.c | 34 +++++++++++++++-----------------
> >>>>    1 file changed, 16 insertions(+), 18 deletions(-)
> >>>>
> >>>> diff --git a/drivers/gpu/drm/i915/i915_perf.c b/drivers/gpu/drm/i915/i915_perf.c
> >>>> index 49597cf31707..ccb20230df2c 100644
> >>>> --- a/drivers/gpu/drm/i915/i915_perf.c
> >>>> +++ b/drivers/gpu/drm/i915/i915_perf.c
> >>>> @@ -210,6 +210,7 @@
> >>>>    #include "i915_oa_cflgt3.h"
> >>>>    #include "i915_oa_cnl.h"
> >>>>    #include "i915_oa_icl.h"
> >>>> +#include "intel_lrc_reg.h"
> >>>>    
> >>>>    /* HW requires this to be a power of two, between 128k and 16M, though driver
> >>>>     * is currently generally designed assuming the largest 16M size is used such
> >>>> @@ -1636,27 +1637,25 @@ static void gen8_update_reg_state_unlocked(struct i915_gem_context *ctx,
> >>>>           u32 ctx_oactxctrl = dev_priv->perf.oa.ctx_oactxctrl_offset;
> >>>>           u32 ctx_flexeu0 = dev_priv->perf.oa.ctx_flexeu0_offset;
> >>>>           /* The MMIO offsets for Flex EU registers aren't contiguous */
> >>>> -       u32 flex_mmio[] = {
> >>>> -               i915_mmio_reg_offset(EU_PERF_CNTL0),
> >>>> -               i915_mmio_reg_offset(EU_PERF_CNTL1),
> >>>> -               i915_mmio_reg_offset(EU_PERF_CNTL2),
> >>>> -               i915_mmio_reg_offset(EU_PERF_CNTL3),
> >>>> -               i915_mmio_reg_offset(EU_PERF_CNTL4),
> >>>> -               i915_mmio_reg_offset(EU_PERF_CNTL5),
> >>>> -               i915_mmio_reg_offset(EU_PERF_CNTL6),
> >>>> +       i915_reg_t flex_regs[] = {
> >>>> +               EU_PERF_CNTL0,
> >>>> +               EU_PERF_CNTL1,
> >>>> +               EU_PERF_CNTL2,
> >>>> +               EU_PERF_CNTL3,
> >>>> +               EU_PERF_CNTL4,
> >>>> +               EU_PERF_CNTL5,
> >>>> +               EU_PERF_CNTL6,
> >>>>           };
> >>>>           int i;
> >>>>    
> >>>> -       reg_state[ctx_oactxctrl] = i915_mmio_reg_offset(GEN8_OACTXCONTROL);
> >>>> -       reg_state[ctx_oactxctrl+1] = (dev_priv->perf.oa.period_exponent <<
> >>>> -                                     GEN8_OA_TIMER_PERIOD_SHIFT) |
> >>>> -                                    (dev_priv->perf.oa.periodic ?
> >>>> -                                     GEN8_OA_TIMER_ENABLE : 0) |
> >>>> -                                    GEN8_OA_COUNTER_RESUME;
> >>>> +       CTX_REG(reg_state, ctx_oactxctrl, GEN8_OACTXCONTROL,
> >>>> +               (dev_priv->perf.oa.period_exponent << GEN8_OA_TIMER_PERIOD_SHIFT) |
> >>>> +               (dev_priv->perf.oa.periodic ? GEN8_OA_TIMER_ENABLE : 0) |
> >>>> +               GEN8_OA_COUNTER_RESUME);
> >>>
> >>> I'll be honest but, I don't think it's CTX_REG() that helps improve the
> >>> readability here.
> >>>
> >>> The really odd part is that this sticks itself into a bare part of the
> >>> register state not surrounded by any LRI and after a BB_END. This
> >>> routine can only work for established contexts, it should not work for
> >>> execlists_init_reg_state.
> >>
> >> Unless I am missing something change is completely mechanical, so any
> >> question marks you have are already there, right? What do you suggest is
> >> the action here?
> > 
> > Sure, the only thing I question of this patch itself is whether
> > CTX_REG() is simply too much horrible obfuscating magic.
> 
> Turn a blind eye if the perceived badness factor is below some 
> threshold? Following patch depends on this one, so if I have to drop 
> this one, then I have to rework the next one etc.. well, it's not the 
> worst problem, so yeah, whatever. Make a call and let me know.

The patch was fine, just worrying about the surrounding code.
-Chris