On Thu, Nov 20, 2025 at 07:47:54PM +0200, Jani Nikula wrote: > On Thu, 20 Nov 2025, Ville Syrjala <[email protected]> wrote: > > From: Ville Syrjälä <[email protected]> > > > > Currently our crtcs are registered in pipe order, and thus > > all the for_intel_crtc*() iterators walk the crtcs in pipe > > order. There are a bunch of places that more or less depend > > on that. Eg. during plane updates and such we want joined > > pipes to be processed back-to-back to give a better chance > > of an atomic update across the whole set. > > > > When we start to register crtcs in a different order we don't > > want to change the order in which the pipes get handled. > > Decouple the for_each_intel_crtc*() iterators from the crtc > > registration order by using a separate list which will be > > sorted by the pipe rather than the crtc index. > > > > We could priobably use a simple array or something, but that > > would require some kind of extra iterator variable for the > > macros, and thus would require a lot more changes. Using > > a linked list keeps the fallout minimal. We can look at > > using a more optimal data structure later. > > I think the list works fine.
I supose. Though we do walk these a lot, and we might be hitting a few more cachelines now, but hopefully they remain clean so there's no ping-pong between CPUs... > > > I also added this extra junk to the atomic state iterators: > > "(__i) = drm_crtc_index(&(crtc)->base), (void)(__i)" > > even though the macro itself no longer needs the "__i" iterator. > > This in case the "__i" is used by the caller, and to > > avoid compiler warnings if it's completely unused now. > > At a glance, I can't find any. Perhaps you could cook up some cocci to > remove the parameter as follow-up? IIRC I already took some kind of stab at hiding the __i inside the macros (using the UNIQUE_ID stuff) but never posted it. But I guess we can avoid that now. Might have to think about doing the same to the drm core macros as well. > > > Signed-off-by: Ville Syrjälä <[email protected]> > > --- > > drivers/gpu/drm/i915/display/intel_crtc.c | 20 +++++ > > drivers/gpu/drm/i915/display/intel_display.h | 90 ++++++++----------- > > .../gpu/drm/i915/display/intel_display_core.h | 3 + > > .../drm/i915/display/intel_display_driver.c | 1 + > > .../drm/i915/display/intel_display_types.h | 1 + > > drivers/gpu/drm/xe/display/xe_display.c | 1 + > > 6 files changed, 64 insertions(+), 52 deletions(-) > > > > diff --git a/drivers/gpu/drm/i915/display/intel_crtc.c > > b/drivers/gpu/drm/i915/display/intel_crtc.c > > index 153ff4b4b52c..7ebbde716238 100644 > > --- a/drivers/gpu/drm/i915/display/intel_crtc.c > > +++ b/drivers/gpu/drm/i915/display/intel_crtc.c > > @@ -209,6 +209,8 @@ static struct intel_crtc *intel_crtc_alloc(void) > > crtc->base.state = &crtc_state->uapi; > > crtc->config = crtc_state; > > > > + INIT_LIST_HEAD(&crtc->pipe_head); > > + > > return crtc; > > } > > > > @@ -222,6 +224,8 @@ static void intel_crtc_destroy(struct drm_crtc *_crtc) > > { > > struct intel_crtc *crtc = to_intel_crtc(_crtc); > > > > + list_del(&crtc->pipe_head); > > + > > cpu_latency_qos_remove_request(&crtc->vblank_pm_qos); > > > > drm_crtc_cleanup(&crtc->base); > > @@ -308,6 +312,20 @@ static const struct drm_crtc_funcs i8xx_crtc_funcs = { > > .get_vblank_timestamp = intel_crtc_get_vblank_timestamp, > > }; > > > > +static void add_crtc_to_pipe_list(struct intel_display *display, struct > > intel_crtc *crtc) > > +{ > > + struct intel_crtc *iter; > > + > > + list_for_each_entry(iter, &display->pipe_list, pipe_head) { > > + if (iter->pipe > crtc->pipe) { > > Nitpick, somehow I found it easier to think of this in reverse order, > "crtc->pipe < iter->pipe", but could be just me. *shrug*. Yeah, I suppose that might be better. Would at least match the order of arguments to list_add_tail(), which does match the order they end up on the list. > > > + list_add_tail(&crtc->pipe_head, &iter->pipe_head); > > + return; > > + } > > + } > > + > > + list_add_tail(&crtc->pipe_head, &display->pipe_list); > > +} > > + > > int intel_crtc_init(struct intel_display *display, enum pipe pipe) > > { > > struct intel_plane *primary, *cursor; > > @@ -398,6 +416,8 @@ int intel_crtc_init(struct intel_display *display, enum > > pipe pipe) > > if (HAS_CASF(display)) > > drm_crtc_create_sharpness_strength_property(&crtc->base); > > > > + add_crtc_to_pipe_list(display, crtc); > > + > > return 0; > > > > fail: > > diff --git a/drivers/gpu/drm/i915/display/intel_display.h > > b/drivers/gpu/drm/i915/display/intel_display.h > > index bcc6ccb69d2b..ac83d4f09bb9 100644 > > --- a/drivers/gpu/drm/i915/display/intel_display.h > > +++ b/drivers/gpu/drm/i915/display/intel_display.h > > @@ -238,22 +238,23 @@ enum phy_fia { > > base.head) \ > > for_each_if((intel_plane)->pipe == (intel_crtc)->pipe) > > > > -#define for_each_intel_crtc(dev, intel_crtc) > > \ > > - list_for_each_entry(intel_crtc, \ > > - &(dev)->mode_config.crtc_list, \ > > - base.head) > > +#define for_each_intel_crtc(dev, crtc) \ > > + list_for_each_entry((crtc), \ > > + &to_intel_display(dev)->pipe_list, \ > > + pipe_head) > > > > -#define for_each_intel_crtc_in_pipe_mask(dev, intel_crtc, pipe_mask) > > \ > > - list_for_each_entry(intel_crtc, \ > > - &(dev)->mode_config.crtc_list, \ > > - base.head) \ > > - for_each_if((pipe_mask) & BIT(intel_crtc->pipe)) > > +#define for_each_intel_crtc_reverse(dev, crtc) \ > > + list_for_each_entry_reverse((crtc), \ > > + &to_intel_display(dev)->pipe_list, \ > > + pipe_head) > > > > -#define for_each_intel_crtc_in_pipe_mask_reverse(dev, intel_crtc, > > pipe_mask) \ > > - list_for_each_entry_reverse((intel_crtc), > > \ > > - &(dev)->mode_config.crtc_list, > > \ > > - base.head) > > \ > > - for_each_if((pipe_mask) & BIT((intel_crtc)->pipe)) > > +#define for_each_intel_crtc_in_pipe_mask(dev, crtc, pipe_mask) \ > > + for_each_intel_crtc((dev), (crtc)) \ > > + for_each_if((pipe_mask) & BIT((crtc)->pipe)) > > + > > +#define for_each_intel_crtc_in_pipe_mask_reverse(dev, crtc, pipe_mask) \ > > + for_each_intel_crtc_reverse((dev), (crtc)) \ > > + for_each_if((pipe_mask) & BIT((crtc)->pipe)) > > > > #define for_each_intel_encoder(dev, intel_encoder) \ > > list_for_each_entry(intel_encoder, \ > > @@ -295,14 +296,6 @@ enum phy_fia { > > (__i)++) \ > > for_each_if(plane) > > > > -#define for_each_old_intel_crtc_in_state(__state, crtc, old_crtc_state, > > __i) \ > > - for ((__i) = 0; \ > > - (__i) < (__state)->base.dev->mode_config.num_crtc && \ > > - ((crtc) = to_intel_crtc((__state)->base.crtcs[__i].ptr), \ > > - (old_crtc_state) = > > to_intel_crtc_state((__state)->base.crtcs[__i].old_state), 1); \ > > - (__i)++) \ > > - for_each_if(crtc) > > - > > #define for_each_new_intel_plane_in_state(__state, plane, new_plane_state, > > __i) \ > > for ((__i) = 0; \ > > (__i) < (__state)->base.dev->mode_config.num_total_plane && \ > > @@ -311,22 +304,6 @@ enum phy_fia { > > (__i)++) \ > > for_each_if(plane) > > > > -#define for_each_new_intel_crtc_in_state(__state, crtc, new_crtc_state, > > __i) \ > > - for ((__i) = 0; \ > > - (__i) < (__state)->base.dev->mode_config.num_crtc && \ > > - ((crtc) = to_intel_crtc((__state)->base.crtcs[__i].ptr), \ > > - (new_crtc_state) = > > to_intel_crtc_state((__state)->base.crtcs[__i].new_state), 1); \ > > - (__i)++) \ > > - for_each_if(crtc) > > - > > -#define for_each_new_intel_crtc_in_state_reverse(__state, crtc, > > new_crtc_state, __i) \ > > - for ((__i) = (__state)->base.dev->mode_config.num_crtc - 1; \ > > - (__i) >= 0 && \ > > - ((crtc) = to_intel_crtc((__state)->base.crtcs[__i].ptr), \ > > - (new_crtc_state) = > > to_intel_crtc_state((__state)->base.crtcs[__i].new_state), 1); \ > > - (__i)--) \ > > - for_each_if(crtc) > > - > > #define for_each_oldnew_intel_plane_in_state(__state, plane, > > old_plane_state, new_plane_state, __i) \ > > for ((__i) = 0; \ > > (__i) < (__state)->base.dev->mode_config.num_total_plane && \ > > @@ -336,23 +313,32 @@ enum phy_fia { > > (__i)++) \ > > for_each_if(plane) > > > > +#define for_each_old_intel_crtc_in_state(__state, crtc, old_crtc_state, > > __i) \ > > + for_each_intel_crtc((__state)->base.dev, (crtc)) \ > > + for_each_if(((__i) = drm_crtc_index(&(crtc)->base), > > (void)(__i), \ > > + (old_crtc_state) = > > intel_atomic_get_old_crtc_state((__state), (crtc)))) > > + > > +#define for_each_new_intel_crtc_in_state(__state, crtc, new_crtc_state, > > __i) \ > > + for_each_intel_crtc((__state)->base.dev, (crtc)) \ > > + for_each_if(((__i) = drm_crtc_index(&(crtc)->base), > > (void)(__i), \ > > + (new_crtc_state) = > > intel_atomic_get_new_crtc_state((__state), (crtc)))) > > + > > +#define for_each_new_intel_crtc_in_state_reverse(__state, crtc, > > new_crtc_state, __i) \ > > + for_each_intel_crtc_reverse((__state)->base.dev, (crtc)) \ > > + for_each_if(((__i) = drm_crtc_index(&(crtc)->base), > > (void)(__i), \ > > + (new_crtc_state) = > > intel_atomic_get_new_crtc_state((__state), (crtc)))) > > + > > #define for_each_oldnew_intel_crtc_in_state(__state, crtc, old_crtc_state, > > new_crtc_state, __i) \ > > - for ((__i) = 0; \ > > - (__i) < (__state)->base.dev->mode_config.num_crtc && \ > > - ((crtc) = to_intel_crtc((__state)->base.crtcs[__i].ptr), \ > > - (old_crtc_state) = > > to_intel_crtc_state((__state)->base.crtcs[__i].old_state), \ > > - (new_crtc_state) = > > to_intel_crtc_state((__state)->base.crtcs[__i].new_state), 1); \ > > - (__i)++) \ > > - for_each_if(crtc) > > + for_each_intel_crtc((__state)->base.dev, (crtc)) \ > > + for_each_if(((__i) = drm_crtc_index(&(crtc)->base), > > (void)(__i), \ > > + (old_crtc_state) = > > intel_atomic_get_old_crtc_state((__state), (crtc)), \ > > + (new_crtc_state) = > > intel_atomic_get_new_crtc_state((__state), (crtc)))) > > > > #define for_each_oldnew_intel_crtc_in_state_reverse(__state, crtc, > > old_crtc_state, new_crtc_state, __i) \ > > - for ((__i) = (__state)->base.dev->mode_config.num_crtc - 1; \ > > - (__i) >= 0 && \ > > - ((crtc) = to_intel_crtc((__state)->base.crtcs[__i].ptr), \ > > - (old_crtc_state) = > > to_intel_crtc_state((__state)->base.crtcs[__i].old_state), \ > > - (new_crtc_state) = > > to_intel_crtc_state((__state)->base.crtcs[__i].new_state), 1); \ > > - (__i)--) \ > > - for_each_if(crtc) > > + for_each_intel_crtc_reverse((__state)->base.dev, (crtc)) \ > > + for_each_if(((__i) = drm_crtc_index(&(crtc)->base), > > (void)(__i), \ > > + (old_crtc_state) = > > intel_atomic_get_old_crtc_state((__state), (crtc)), \ > > + (new_crtc_state) = > > intel_atomic_get_new_crtc_state((__state), (crtc)))) > > These were a PITA to go through, but I think it's fine. Knocks wood. > > Thanks for doing this. > > Reviewed-by: Jani Nikula <[email protected]> > > > > > #define intel_atomic_crtc_state_for_each_plane_state( \ > > plane, plane_state, \ > > diff --git a/drivers/gpu/drm/i915/display/intel_display_core.h > > b/drivers/gpu/drm/i915/display/intel_display_core.h > > index 9b8414b77c15..4f4d5c314394 100644 > > --- a/drivers/gpu/drm/i915/display/intel_display_core.h > > +++ b/drivers/gpu/drm/i915/display/intel_display_core.h > > @@ -294,6 +294,9 @@ struct intel_display { > > /* Parent, or core, driver functions exposed to display */ > > const struct intel_display_parent_interface *parent; > > > > + /* list of all intel_crtcs sorted by pipe */ > > + struct list_head pipe_list; > > + > > /* Display functions */ > > struct { > > /* Top level crtc-ish functions */ > > diff --git a/drivers/gpu/drm/i915/display/intel_display_driver.c > > b/drivers/gpu/drm/i915/display/intel_display_driver.c > > index 7e000ba3e08b..32726906e550 100644 > > --- a/drivers/gpu/drm/i915/display/intel_display_driver.c > > +++ b/drivers/gpu/drm/i915/display/intel_display_driver.c > > @@ -119,6 +119,7 @@ static void intel_mode_config_init(struct intel_display > > *display) > > > > drm_mode_config_init(display->drm); > > INIT_LIST_HEAD(&display->global.obj_list); > > + INIT_LIST_HEAD(&display->pipe_list); > > > > mode_config->min_width = 0; > > mode_config->min_height = 0; > > diff --git a/drivers/gpu/drm/i915/display/intel_display_types.h > > b/drivers/gpu/drm/i915/display/intel_display_types.h > > index 38702a9e0f50..1c2bd9445795 100644 > > --- a/drivers/gpu/drm/i915/display/intel_display_types.h > > +++ b/drivers/gpu/drm/i915/display/intel_display_types.h > > @@ -1441,6 +1441,7 @@ struct intel_flipq { > > > > struct intel_crtc { > > struct drm_crtc base; > > + struct list_head pipe_head; > > enum pipe pipe; > > /* > > * Whether the crtc and the connected output pipeline is active. Implies > > diff --git a/drivers/gpu/drm/xe/display/xe_display.c > > b/drivers/gpu/drm/xe/display/xe_display.c > > index e3320d9e6314..cfcbc7dd8638 100644 > > --- a/drivers/gpu/drm/xe/display/xe_display.c > > +++ b/drivers/gpu/drm/xe/display/xe_display.c > > @@ -22,6 +22,7 @@ > > #include "intel_audio.h" > > #include "intel_bw.h" > > #include "intel_display.h" > > +#include "intel_display_core.h" > > #include "intel_display_device.h" > > #include "intel_display_driver.h" > > #include "intel_display_irq.h" > > -- > Jani Nikula, Intel -- Ville Syrjälä Intel
