On Tue, 04 Jul 2023, Jani Nikula <jani.nikula@xxxxxxxxx> wrote: > Fix a race in unclaimed reg debug. This does increase the code size for > CONFIG_DRM_I915_DEBUG_MMIO=y. > > However, also add an optimization to reduce code size for > CONFIG_DRM_I915_DEBUG_MMIO=n. > > Do we care about the bloat for the debug config? > > Before/after for both CONFIG_DRM_I915_DEBUG_MMIO=y and =n. > > > $ scripts/bloat-o-meter intel_uncore.before.with-debug.o intel_uncore.after.with-debug.o > add/remove: 0/2 grow/shrink: 10/0 up/down: 927/-149 (778) > Function old new delta > fwtable_read16 721 821 +100 > fwtable_read32 719 817 +98 > fwtable_read8 722 818 +96 > fwtable_read64 722 817 +95 > gen6_write16 679 772 +93 > gen6_write8 678 769 +91 > gen6_write32 677 768 +91 > fwtable_write16 742 831 +89 > fwtable_write8 741 828 +87 > fwtable_write32 740 827 +87 > __pfx___unclaimed_reg_debug 16 - -16 > __unclaimed_reg_debug 133 - -133 Looking at the size decrease for __unclaimed_reg_debug(), it occurs to me the compiler wasn't previously inlining unclaimed_reg_debug() regardless of the inline keyword. It just bundled unclaimed_reg_debug() together with __unclaimed_reg_debug(), and called it. The juggling here actually makes them both inline, which presumably was the original intention. The optimization for CONFIG_DRM_I915_DEBUG_MMIO=n below is the good stuff. BR, Jani. > Total: Before=33797, After=34575, chg +2.30% > > $ scripts/bloat-o-meter intel_uncore.before.without-debug.o intel_uncore.after.without-debug.o > add/remove: 0/2 grow/shrink: 0/10 up/down: 0/-2557 (-2557) > Function old new delta > __pfx___unclaimed_reg_debug 16 - -16 > __unclaimed_reg_debug 133 - -133 > gen6_write8 678 446 -232 > gen6_write32 677 445 -232 > gen6_write16 679 447 -232 > fwtable_read64 722 482 -240 > fwtable_read32 719 479 -240 > fwtable_read16 721 481 -240 > fwtable_read8 722 480 -242 > fwtable_write8 741 491 -250 > fwtable_write32 740 490 -250 > fwtable_write16 742 492 -250 > Total: Before=33797, After=31240, chg -7.57% > > Cc: Lee Shawn C <shawn.c.lee@xxxxxxxxx> > > Jani Nikula (3): > drm/i915/uncore: split unclaimed_reg_debug() to header and footer > drm/i915/uncore: fix race around i915->params.mmio_debug > drm/i915/uncore: optimize CONFIG_DRM_I915_DEBUG_MMIO=n more > > drivers/gpu/drm/i915/intel_uncore.c | 47 ++++++++++++++++++----------- > 1 file changed, 29 insertions(+), 18 deletions(-) -- Jani Nikula, Intel Open Source Graphics Center
