[05/24] efi/libstub: Optimize for size instead of speed

Message ID	20200518190716.751506-6-nivedita@alum.mit.edu
State	New
Headers	show Return-Path: <SRS0=pLtV=7A=vger.kernel.org=linux-efi-owner@kernel.org> From: Arvind Sankar <nivedita@alum.mit.edu> To: Ard Biesheuvel <ardb@kernel.org> Cc: linux-efi@vger.kernel.org Subject: [PATCH 05/24] efi/libstub: Optimize for size instead of speed Date: Mon, 18 May 2020 15:06:57 -0400 Message-Id: <20200518190716.751506-6-nivedita@alum.mit.edu> In-Reply-To: <20200518190716.751506-1-nivedita@alum.mit.edu> References: <20200518190716.751506-1-nivedita@alum.mit.edu> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-efi-owner@vger.kernel.org Precedence: bulk
Series	[01/24] efi/libstub: Include dependencies of efistub.h \| expand [01/24] efi/libstub: Include dependencies of efistub.h [03/24] efi/libstub: Buffer output of efi_puts [05/24] efi/libstub: Optimize for size instead of speed [06/24] efi/printf: Drop %n format and L qualifier [09/24] efi/printf: Fix minor bug in precision handling [11/24] efi/printf: Factor out width/precision parsing [12/24] efi/printf: Factor out integer argument retrieval [14/24] efi/printf: Refactor code to consolidate padding and output [16/24] efi/printf: Turn vsprintf into vsnprintf [19/24] efi/gop: Add an option to list out the available GOP modes [22/24] efi/libstub: Use %ls for filename [23/24] efi/libstub: Get the exact UTF-8 length

Message ID

20200518190716.751506-6-nivedita@alum.mit.edu

State

New

Headers

From: Arvind Sankar <nivedita@alum.mit.edu>
To: Ard Biesheuvel <ardb@kernel.org>
Cc: linux-efi@vger.kernel.org
Subject: [PATCH 05/24] efi/libstub: Optimize for size instead of speed
Date: Mon, 18 May 2020 15:06:57 -0400
Message-Id: <20200518190716.751506-6-nivedita@alum.mit.edu>
In-Reply-To: <20200518190716.751506-1-nivedita@alum.mit.edu>
References: <20200518190716.751506-1-nivedita@alum.mit.edu>
MIME-Version: 1.0
Content-Transfer-Encoding: 8bit
Sender: linux-efi-owner@vger.kernel.org
Precedence: bulk

Series

[01/24] efi/libstub: Include dependencies of efistub.h | expand

Commit Message

Arvind Sankar May 18, 2020, 7:06 p.m. UTC

Reclaim the bloat from the addition of printf by optimizing the stub for
size. With gcc 9, the text size of the stub is:

ARCH    before  +printf    -Os
arm      35197    37889  34638
arm64    34883    38159  34479
i386     18571    21657  17025
x86_64   25677    29328  22144

Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu>
---
 drivers/firmware/efi/libstub/Makefile | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/firmware/efi/libstub/Makefile b/drivers/firmware/efi/libstub/Makefile
index fb34c9d14a3c..034d71663b1e 100644
--- a/drivers/firmware/efi/libstub/Makefile
+++ b/drivers/firmware/efi/libstub/Makefile
@@ -7,7 +7,7 @@ 
 #
 cflags-$(CONFIG_X86_32)		:= -march=i386
 cflags-$(CONFIG_X86_64)		:= -mcmodel=small
-cflags-$(CONFIG_X86)		+= -m$(BITS) -D__KERNEL__ -O2 \
+cflags-$(CONFIG_X86)		+= -m$(BITS) -D__KERNEL__ \
 				   -fPIC -fno-strict-aliasing -mno-red-zone \
 				   -mno-mmx -mno-sse -fshort-wchar \
 				   -Wno-pointer-sign \
@@ -25,7 +25,7 @@  cflags-$(CONFIG_ARM)		:= $(subst $(CC_FLAGS_FTRACE),,$(KBUILD_CFLAGS)) \
 
 cflags-$(CONFIG_EFI_GENERIC_STUB) += -I$(srctree)/scripts/dtc/libfdt
 
-KBUILD_CFLAGS			:= $(cflags-y) -DDISABLE_BRANCH_PROFILING \
+KBUILD_CFLAGS			:= $(cflags-y) -Os -DDISABLE_BRANCH_PROFILING \
 				   -include $(srctree)/drivers/firmware/efi/libstub/hidden.h \
 				   -D__NO_FORTIFY \
 				   $(call cc-option,-ffreestanding) \

[05/24] efi/libstub: Optimize for size instead of speed

Commit Message

Patch