On Fri, Mar 15, 2019 at 12:13 AM Tvrtko Ursulin <tvrtko.ursulin@xxxxxxxxxxxxxxx> wrote: > > > On 15/03/2019 06:56, Tvrtko Ursulin wrote: > > > > On 15/03/2019 00:52, Chris Wilson wrote: > >> Quoting José Roberto de Souza (2019-03-15 00:42:35) > >>> We don't have any platform that is composed by 2 or more platforms so > >>> we don't need a mask, lets drop it and remove the actual limit of 32 > >>> platforms. > > > > Platform mask was a nifty trick to compile tests like IS_SKYLAKE || > > IS_BROADWELL etc into a single conditional. > > > >> gcc doesn't entirely agree, this is a net loss here (i.e. code size > >> increases). > > > > Perhaps the size re-gain of dropping the platform mask could be checked > > against the size gain of making the mask 64 bit. current: text data bss dec hex filename 1836533 40454 4176 1881163 1cb44b drivers/gpu/drm/i915/i915.o.old 64 bit bitmask: 1836757 40454 4176 1881387 1cb52b drivers/gpu/drm/i915/i915.o no platform_mask: 1837591 40454 4176 1882221 1cb86d drivers/gpu/drm/i915/i915.o So current situation to "just use a number" we are talking about 1k here, which for me looks acceptable. Alternative is the 64-bit bitmask, with ~200 bytes. Lucas De Marchi > > One possible alternative could be splitting the 64-bit platform mask > into two 32-bit dwords. Like: > > u32 platform_mask[2]; > > #define IS_PLATFORM(p) (platform_mask[p / 32] & BIT(p % 32)) > > And a bit of jigging the enum space so that we don't end up with > something often tested together on the dword boundary. > > In fact I had a prototype many months ago which went a step further and > interleaved platform with gen mask, in some sized chunks, so even > IS_PLATFORM || IS_GEN checks could be merged. This included the > sub-platform thing as well with the ULT/ULX/LP stuff I think.. maybe I > need to dig this out to see how it worked. > > Regards, > > Tvrtko > _______________________________________________ > Intel-gfx mailing list > Intel-gfx@xxxxxxxxxxxxxxxxxxxxx > https://lists.freedesktop.org/mailman/listinfo/intel-gfx -- Lucas De Marchi _______________________________________________ Intel-gfx mailing list Intel-gfx@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/intel-gfx
