6b3ae58efc
In struct page_cgroup, we have a full word for flags but only a few are reserved. Use the remaining upper bits to encode, depending on configuration, the node or the section, to enable page_cgroup-to-page lookups without a direct pointer. This saves a full word for every page in a system with memory cgroups enabled. Signed-off-by: Johannes Weiner <hannes@cmpxchg.org> Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Daisuke Nishimura <nishimura@mxp.nes.nec.co.jp> Cc: Balbir Singh <balbir@linux.vnet.ibm.com> Cc: Minchan Kim <minchan.kim@gmail.com> Cc: Randy Dunlap <randy.dunlap@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
21 lines
600 B
C
21 lines
600 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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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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/* End of constants */
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}
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