When CONFIG_ARCH_KEEP_MEMBLOCK not set, we expect to discard related
code and data. But it doesn't until CONFIG_MEMORY_HOTPLUG not set
neither.
This patch puts memblock's .text/.data into its own section, so that it
only depends on CONFIG_ARCH_KEEP_MEMBLOCK to discard related code and
data.
After this, from the log message in mem_init_print_info(), init size
increase from 2420K to 2432K on arch x86.
Signed-off-by: Wei Yang <richard.weiyang@xxxxxxxxx>
---
v2: fix orphan section for powerpc
---
arch/powerpc/kernel/vmlinux.lds.S | 1 +
include/asm-generic/vmlinux.lds.h | 14 +++++++++++++-
include/linux/memblock.h | 8 ++++----
3 files changed, 18 insertions(+), 5 deletions(-)
diff --git a/arch/powerpc/kernel/vmlinux.lds.S b/arch/powerpc/kernel/vmlinux.lds.S
index f420df7888a7..d6d33bec597a 100644
--- a/arch/powerpc/kernel/vmlinux.lds.S
+++ b/arch/powerpc/kernel/vmlinux.lds.S
@@ -125,6 +125,7 @@ SECTIONS
*(.text.asan.* .text.tsan.*)
MEM_KEEP(init.text)
MEM_KEEP(exit.text)
+ MEMBLOCK_KEEP(init.text)
} :text
. = ALIGN(PAGE_SIZE);
diff --git a/include/asm-generic/vmlinux.lds.h b/include/asm-generic/vmlinux.lds.h
index f7749d0f2562..775c5eedb9e6 100644
--- a/include/asm-generic/vmlinux.lds.h
+++ b/include/asm-generic/vmlinux.lds.h
@@ -147,6 +147,14 @@
#define MEM_DISCARD(sec) *(.mem##sec)
#endif
+#if defined(CONFIG_ARCH_KEEP_MEMBLOCK)
+#define MEMBLOCK_KEEP(sec) *(.mb##sec)
+#define MEMBLOCK_DISCARD(sec)
+#else
+#define MEMBLOCK_KEEP(sec)
+#define MEMBLOCK_DISCARD(sec) *(.mb##sec)
+#endif
+
#ifndef CONFIG_HAVE_DYNAMIC_FTRACE_NO_PATCHABLE
#define KEEP_PATCHABLE KEEP(*(__patchable_function_entries))
#define PATCHABLE_DISCARDS
@@ -356,6 +364,7 @@
*(.ref.data) \
*(.data..shared_aligned) /* percpu related */ \
MEM_KEEP(init.data*) \
+ MEMBLOCK_KEEP(init.data*) \
*(.data.unlikely) \
__start_once = .; \
*(.data.once) \
@@ -573,6 +582,7 @@
*(.ref.text) \
*(.text.asan.* .text.tsan.*) \
MEM_KEEP(init.text*) \
+ MEMBLOCK_KEEP(init.text*) \
/* sched.text is aling to function alignment to secure we have same
@@ -680,6 +690,7 @@
KEEP(*(SORT(___kentry+*))) \
*(.init.data .init.data.*) \
MEM_DISCARD(init.data*) \
+ MEMBLOCK_DISCARD(init.data*) \
KERNEL_CTORS() \
MCOUNT_REC() \
*(.init.rodata .init.rodata.*) \
@@ -706,7 +717,8 @@
#define INIT_TEXT \
*(.init.text .init.text.*) \
*(.text.startup) \
- MEM_DISCARD(init.text*)
+ MEM_DISCARD(init.text*) \
+ MEMBLOCK_DISCARD(init.text*)
#define EXIT_DATA \
*(.exit.data .exit.data.*) \
diff --git a/include/linux/memblock.h b/include/linux/memblock.h
index e2082240586d..3e1f1d42dde7 100644
--- a/include/linux/memblock.h
+++ b/include/linux/memblock.h
@@ -100,13 +100,13 @@ struct memblock {
extern struct memblock memblock;
+#define __init_memblock __section(".mbinit.text") __cold notrace \
+ __latent_entropy
+#define __initdata_memblock __section(".mbinit.data")
+
#ifndef CONFIG_ARCH_KEEP_MEMBLOCK
-#define __init_memblock __meminit
-#define __initdata_memblock __meminitdata
void memblock_discard(void);
#else
-#define __init_memblock
-#define __initdata_memblock
static inline void memblock_discard(void) {}
#endif
--
2.34.1
