[PATCH v3 0/2] Linker script cleanup patches for arm

[PATCH v3 0/2] Linker script cleanup patches for arm

[Tim Abbott]

This is an updated version of the patch series I sent in late July
cleaning up the arm architecture's linker scripts.  Version 2 was
rebased on top of Linus's current master; version 3 contains a fix
for a problem with CONFIG_XIP_KERNEL noted by Russell King.

This cross-architecture linker script cleanup project is in
preparation for adding support for building the kernel with
-ffunction-sections -fdata-sections, which is a prerequisite for
Ksplice.

	-Tim Abbott

Nelson Elhage (1):
  arm: Clean up linker script using new linker script macros.

Tim Abbott (1):
  arm: convert to use __HEAD and HEAD_TEXT macros.

 arch/arm/kernel/head-nommu.S  |    2 +-
 arch/arm/kernel/head.S        |    2 +-
 arch/arm/kernel/vmlinux.lds.S |   86 ++++++++++++----------------------------
 3 files changed, 28 insertions(+), 62 deletions(-)

[PATCH v3 1/2] arm: convert to use __HEAD and HEAD_TEXT macros.

[Tim Abbott]

This has the consequence of changing the section name used for head
code from ".text.head" to ".head.text".  Since this commit changes all
users in the architecture, this change should be harmless.

The .text.head output section is eliminated and the head text code is
included at the start of the .init output section.

Signed-off-by: Tim Abbott <tabbott@ksplice.com>
Cc: Russell King <rmk+kernel@arm.linux.org.uk>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
---
 arch/arm/kernel/head-nommu.S  |    2 +-
 arch/arm/kernel/head.S        |    2 +-
 arch/arm/kernel/vmlinux.lds.S |    8 +++-----
 3 files changed, 5 insertions(+), 7 deletions(-)

diff --git a/arch/arm/kernel/head-nommu.S b/arch/arm/kernel/head-nommu.S
index e5dfc28..573b803 100644
--- a/arch/arm/kernel/head-nommu.S
+++ b/arch/arm/kernel/head-nommu.S
@@ -32,7 +32,7 @@
  * numbers for r1.
  *
  */
-	.section ".text.head", "ax"
+	__HEAD
 ENTRY(stext)
 	setmode	PSR_F_BIT | PSR_I_BIT | SVC_MODE, r9 @ ensure svc mode
 						@ and irqs disabled
diff --git a/arch/arm/kernel/head.S b/arch/arm/kernel/head.S
index 38ccbe1..eb62bf9 100644
--- a/arch/arm/kernel/head.S
+++ b/arch/arm/kernel/head.S
@@ -74,7 +74,7 @@
  * crap here - that's what the boot loader (or in extreme, well justified
  * circumstances, zImage) is for.
  */
-	.section ".text.head", "ax"
+	__HEAD
 ENTRY(stext)
 	setmode	PSR_F_BIT | PSR_I_BIT | SVC_MODE, r9 @ ensure svc mode
 						@ and irqs disabled
diff --git a/arch/arm/kernel/vmlinux.lds.S b/arch/arm/kernel/vmlinux.lds.S
index 5cc4812..d3fbd98 100644
--- a/arch/arm/kernel/vmlinux.lds.S
+++ b/arch/arm/kernel/vmlinux.lds.S
@@ -24,13 +24,11 @@ SECTIONS
 #else
 	. = PAGE_OFFSET + TEXT_OFFSET;
 #endif
-	.text.head : {
-		_stext = .;
-		_sinittext = .;
-		*(.text.head)
-	}
 
 	.init : {			/* Init code and data		*/
+		_stext = .;
+		_sinittext = .;
+			HEAD_TEXT
 			INIT_TEXT
 		_einittext = .;
 		__proc_info_begin = .;
-- 
1.6.3.3

[PATCH v3 2/2] arm: Clean up linker script using new linker script macros.

[Tim Abbott]

From: Nelson Elhage <nelhage@ksplice.com>

This patch is mostly a straightforward translation. The primary side
effect to the resulting vmlinux should be to increase the alignment on
the initramfs to the standard PAGE_SIZE from 32 bytes.

Signed-off-by: Nelson Elhage <nelhage@ksplice.com>
Cc: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Tim Abbott <tabbott@ksplice.com>
---
 arch/arm/kernel/vmlinux.lds.S |   78 ++++++++++++-----------------------------
 1 files changed, 23 insertions(+), 55 deletions(-)

diff --git a/arch/arm/kernel/vmlinux.lds.S b/arch/arm/kernel/vmlinux.lds.S
index d3fbd98..35d4a20 100644
--- a/arch/arm/kernel/vmlinux.lds.S
+++ b/arch/arm/kernel/vmlinux.lds.S
@@ -40,43 +40,31 @@ SECTIONS
 		__tagtable_begin = .;
 			*(.taglist.init)
 		__tagtable_end = .;
-		. = ALIGN(16);
-		__setup_start = .;
-			*(.init.setup)
-		__setup_end = .;
+
+		INIT_SETUP(16)
+
 		__early_begin = .;
 			*(.early_param.init)
 		__early_end = .;
-		__initcall_start = .;
-			INITCALLS
-		__initcall_end = .;
-		__con_initcall_start = .;
-			*(.con_initcall.init)
-		__con_initcall_end = .;
-		__security_initcall_start = .;
-			*(.security_initcall.init)
-		__security_initcall_end = .;
-#ifdef CONFIG_BLK_DEV_INITRD
-		. = ALIGN(32);
-		__initramfs_start = .;
-			usr/built-in.o(.init.ramfs)
-		__initramfs_end = .;
-#endif
-		. = ALIGN(PAGE_SIZE);
-		__per_cpu_load = .;
-		__per_cpu_start = .;
-			*(.data.percpu.page_aligned)
-			*(.data.percpu)
-			*(.data.percpu.shared_aligned)
-		__per_cpu_end = .;
+
+		INIT_CALLS
+		CON_INITCALL
+		SECURITY_INITCALL
+		INIT_RAM_FS
+
 #ifndef CONFIG_XIP_KERNEL
 		__init_begin = _stext;
 		INIT_DATA
-		. = ALIGN(PAGE_SIZE);
-		__init_end = .;
 #endif
 	}
 
+	PERCPU(PAGE_SIZE)
+
+#ifndef CONFIG_XIP_KERNEL
+	. = ALIGN(PAGE_SIZE);
+	__init_end = .;
+#endif
+
 	/DISCARD/ : {			/* Exit code and data		*/
 		EXIT_TEXT
 		EXIT_DATA
@@ -155,7 +143,7 @@ SECTIONS
 		 * first, the init task union, aligned
 		 * to an 8192 byte boundary.
 		 */
-		*(.data.init_task)
+		INIT_TASK_DATA(THREAD_SIZE)
 
 #ifdef CONFIG_XIP_KERNEL
 		. = ALIGN(PAGE_SIZE);
@@ -165,17 +153,8 @@ SECTIONS
 		__init_end = .;
 #endif
 
-		. = ALIGN(PAGE_SIZE);
-		__nosave_begin = .;
-		*(.data.nosave)
-		. = ALIGN(PAGE_SIZE);
-		__nosave_end = .;
-
-		/*
-		 * then the cacheline aligned data
-		 */
-		. = ALIGN(32);
-		*(.data.cacheline_aligned)
+		NOSAVE_DATA
+		CACHELINE_ALIGNED_DATA(32)
 
 		/*
 		 * The exception fixup table (might need resorting at runtime)
@@ -197,21 +176,10 @@ SECTIONS
 	}
 	_edata_loc = __data_loc + SIZEOF(.data);
 
-	.bss : {
-		__bss_start = .;	/* BSS				*/
-		*(.bss)
-		*(COMMON)
-		__bss_stop = .;
-		_end = .;
-	}
-					/* Stabs debugging sections.	*/
-	.stab 0 : { *(.stab) }
-	.stabstr 0 : { *(.stabstr) }
-	.stab.excl 0 : { *(.stab.excl) }
-	.stab.exclstr 0 : { *(.stab.exclstr) }
-	.stab.index 0 : { *(.stab.index) }
-	.stab.indexstr 0 : { *(.stab.indexstr) }
-	.comment 0 : { *(.comment) }
+	BSS_SECTION(0, 0, 0)
+	_end = .;
+
+	STABS_DEBUG
 }
 
 /*
-- 
1.6.3.3