[PATCH] Move variables in ppc64 head.S from .data to .bss (6fbb49d5) · Commits · 戴 / test

The ppc64 head.S defines several zero-initialized structures, such as the empty_zero_page and the kernel top-level pagetable. Currently they are defined to be in the data section. However, they're not used until after the bss is cleared, so this patch moves them to the bss, saving two and a half pages from the vmlinux. Signed-off-by:

David Gibson <dwg@au1.ibm.com> Signed-off-by:

Paul Mackerras <paulus@samba.org>

arch/ppc64/kernel/head.S

+6 −7

Original line number	Diff line number	Diff line
		@@ -1971,20 +1971,19 @@ _GLOBAL(smp_release_cpus)

		/*
		* We put a few things here that have to be page-aligned.
		* This stuff goes at the beginning of the data segment,
		* which is page-aligned.
		* This stuff goes at the beginning of the bss, which is page-aligned.
		*/
		.data
		.section ".bss"

		.align 12
		.globl sdata
		sdata:

		.globl empty_zero_page
		empty_zero_page:
		.space 4096
		.space PAGE_SIZE

		.globl swapper_pg_dir
		swapper_pg_dir:
		.space 4096
		.space PAGE_SIZE

		/*
		* This space gets a copy of optional info passed to us by the bootstrap

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