[PATCH 4/4] module: Limit ELF includes in linux/module.h to uapi/linux/elf.h

[Petr Pavlu <petr.pavlu@suse.com>]

The linux/module.h header is included by every *.mod.c file to provide
`struct module` and other related definitions. This makes it a "hot"
header, so it should avoid pulling in unnecessary definitions.

The header currently includes linux/elf.h but this is largely unnecessary
because it requires only the base ELF structures, such as Elf_Ehdr and
Elf_Sym, which are declared in uapi/linux/elf.h.

Replace the linux/elf.h include with uapi/linux/elf.h. On x86_64_defconfig,
including linux/module.h alone results in 2.2 MB of preprocessed data. This
change reduces that to 1.5 MB.

Signed-off-by: Petr Pavlu <petr.pavlu@suse.com>
---
 include/linux/module.h | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/include/linux/module.h b/include/linux/module.h
index 7566815fabbe..7661faadbedd 100644
--- a/include/linux/module.h
+++ b/include/linux/module.h
@@ -17,7 +17,6 @@
 #include <linux/cleanup.h>
 #include <linux/kmod.h>
 #include <linux/init.h>
-#include <linux/elf.h>
 #include <linux/stringify.h>
 #include <linux/kobject.h>
 #include <linux/moduleparam.h>
@@ -29,8 +28,9 @@
 #include <linux/srcu.h>
 #include <linux/static_call_types.h>
 #include <linux/dynamic_debug.h>
-
 #include <linux/percpu.h>
+
+#include <uapi/linux/elf.h>
 #include <asm/module.h>
 
 #define MODULE_NAME_LEN __MODULE_NAME_LEN
-- 
2.54.0