On Tue, Apr 29, 2025 at 12:01 PM Alex Hung <alex.h...@amd.com> wrote: > > > > On 4/29/25 09:04, Alex Deucher wrote: > > On Mon, Apr 28, 2025 at 9:57 AM Ray Wu <ray...@amd.com> wrote: > >> > >> From: Alex Hung <alex.h...@amd.com> > >> > >> [WHY & HOW] > >> Remove the unnecessary DC_FP_START/DC_FP_END pair to reduce time in > >> preempt_disable. It also fixes "BUG: sleeping function called from > >> invalid context" error messages because of calling kzalloc with > >> GFP_KERNEL which can sleep. > > > > Is this safe? If this function uses FP or calls a function which uses > > FP, removing these will lead to register corruption. > > I checked dcn32_resource_construct again and I did not find any FP or > functions uses FP, and Aurabindo helped double check. > > I also checked other dnc*_resource_construct (like 321, 35, 351, 36) and > they don't use DC_FP_START/DC_FP_END pair either. > > So it should be safe to remove this pair.
Great. Thanks for verifying. Alex > > > > > Alex > > > >> > >> Reviewed-by: Aurabindo Pillai <aurabindo.pil...@amd.com> > >> Signed-off-by: Alex Hung <alex.h...@amd.com> > >> Signed-off-by: Ray Wu <ray...@amd.com> > >> --- > >> .../gpu/drm/amd/display/dc/resource/dcn32/dcn32_resource.c | 6 ------ > >> 1 file changed, 6 deletions(-) > >> > >> diff --git > >> a/drivers/gpu/drm/amd/display/dc/resource/dcn32/dcn32_resource.c > >> b/drivers/gpu/drm/amd/display/dc/resource/dcn32/dcn32_resource.c > >> index 2a59cc61ed8c..944650cb13de 100644 > >> --- a/drivers/gpu/drm/amd/display/dc/resource/dcn32/dcn32_resource.c > >> +++ b/drivers/gpu/drm/amd/display/dc/resource/dcn32/dcn32_resource.c > >> @@ -2114,8 +2114,6 @@ static bool dcn32_resource_construct( > >> #define REG_STRUCT dccg_regs > >> dccg_regs_init(); > >> > >> - DC_FP_START(); > >> - > >> ctx->dc_bios->regs = &bios_regs; > >> > >> pool->base.res_cap = &res_cap_dcn32; > >> @@ -2501,14 +2499,10 @@ static bool dcn32_resource_construct( > >> if (ASICREV_IS_GC_11_0_3(dc->ctx->asic_id.hw_internal_rev) && > >> (dc->config.sdpif_request_limit_words_per_umc == 0)) > >> dc->config.sdpif_request_limit_words_per_umc = 16; > >> > >> - DC_FP_END(); > >> - > >> return true; > >> > >> create_fail: > >> > >> - DC_FP_END(); > >> - > >> dcn32_resource_destruct(pool); > >> > >> return false; > >> -- > >> 2.43.0 > >> >
