From b0f4b23fc3dbd8c5398e9ea9cf1f16a00d9006a2 Mon Sep 17 00:00:00 2001 From: Nathan Chancellor Date: Tue, 30 Aug 2022 13:34:09 -0700 Subject: [PATCH] drm/amd/display: Mark dml30's UseMinimumDCFCLK() as noinline for stack usage MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit This function consumes a lot of stack space and it blows up the size of dml30_ModeSupportAndSystemConfigurationFull() with clang: drivers/gpu/drm/amd/amdgpu/../display/dc/dml/dcn30/display_mode_vba_30.c:3542:6: error: stack frame size (2200) exceeds limit (2048) in 'dml30_ModeSupportAndSystemConfigurationFull' [-Werror,-Wframe-larger-than] void dml30_ModeSupportAndSystemConfigurationFull(struct display_mode_lib *mode_lib) ^ 1 error generated. Commit a0f7e7f759cf ("drm/amd/display: fix i386 frame size warning") aimed to address this for i386 but it did not help x86_64. To reduce the amount of stack space that dml30_ModeSupportAndSystemConfigurationFull() uses, mark UseMinimumDCFCLK() as noinline, using the _for_stack variant for documentation. While this will increase the total amount of stack usage between the two functions (1632 and 1304 bytes respectively), it will make sure both stay below the limit of 2048 bytes for these files. The aforementioned change does help reduce UseMinimumDCFCLK()'s stack usage so it should not be reverted in favor of this change. Link: https://github.com/ClangBuiltLinux/linux/issues/1681 Reported-by: "Sudip Mukherjee (Codethink)" Tested-by: Maíra Canal Reviewed-by: Rodrigo Siqueira Signed-off-by: Nathan Chancellor Signed-off-by: Rodrigo Siqueira Signed-off-by: Alex Deucher --- drivers/gpu/drm/amd/display/dc/dml/dcn30/display_mode_vba_30.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/gpu/drm/amd/display/dc/dml/dcn30/display_mode_vba_30.c b/drivers/gpu/drm/amd/display/dc/dml/dcn30/display_mode_vba_30.c index c117a97..479e2c1 100644 --- a/drivers/gpu/drm/amd/display/dc/dml/dcn30/display_mode_vba_30.c +++ b/drivers/gpu/drm/amd/display/dc/dml/dcn30/display_mode_vba_30.c @@ -6493,7 +6493,7 @@ static double CalculateUrgentLatency( return ret; } -static void UseMinimumDCFCLK( +static noinline_for_stack void UseMinimumDCFCLK( struct display_mode_lib *mode_lib, struct vba_vars_st *v, int MaxPrefetchMode, -- 2.7.4