597d795a2a
In struct page we have enough space to fit long-size page->ptl there, but we use dynamically-allocated page->ptl if size(spinlock_t) is larger than sizeof(int). It hurts 64-bit architectures with CONFIG_GENERIC_LOCKBREAK, where sizeof(spinlock_t) == 8, but it easily fits into struct page. Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Acked-by: Hugh Dickins <hughd@google.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
27 lines
773 B
C
27 lines
773 B
C
/*
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* Generate definitions needed by the preprocessor.
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* This code generates raw asm output which is post-processed
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* to extract and format the required data.
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*/
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#define __GENERATING_BOUNDS_H
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/* Include headers that define the enum constants of interest */
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#include <linux/page-flags.h>
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#include <linux/mmzone.h>
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#include <linux/kbuild.h>
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#include <linux/page_cgroup.h>
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#include <linux/log2.h>
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#include <linux/spinlock_types.h>
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void foo(void)
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{
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/* The enum constants to put into include/generated/bounds.h */
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DEFINE(NR_PAGEFLAGS, __NR_PAGEFLAGS);
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DEFINE(MAX_NR_ZONES, __MAX_NR_ZONES);
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DEFINE(NR_PCG_FLAGS, __NR_PCG_FLAGS);
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#ifdef CONFIG_SMP
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DEFINE(NR_CPUS_BITS, ilog2(CONFIG_NR_CPUS));
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#endif
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DEFINE(SPINLOCK_SIZE, sizeof(spinlock_t));
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/* End of constants */
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}
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