Commit 8eb42bea authored by John Hubbard's avatar John Hubbard Committed by Linus Torvalds
Browse files

mm/migrate: de-duplicate migrate_reason strings 

In order to remove the need to manually keep three different files in
synch, provide a common definition of the mapping between enum
migrate_reason, and the associated strings for each enum item.

1. Use the tracing system's mapping of enums to strings, by redefining
   and reusing the MIGRATE_REASON and supporting macros, and using that
   to populate the string array in mm/debug.c.

2. Move enum migrate_reason to migrate_mode.h. This is not strictly
   necessary for this patch, but migrate mode and migrate reason go
   together, so this will slightly clarify things.

Link: https://lkml.kernel.org/r/20210922041755.141817-2-jhubbard@nvidia.com


Signed-off-by: default avatarJohn Hubbard <jhubbard@nvidia.com>
Reviewed-by: default avatarWeizhao Ouyang <o451686892@gmail.com>
Cc: "Huang, Ying" <ying.huang@intel.com>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent b5389086

include/linux/migrate.h

+1 −18
Original line number Diff line number Diff line
@@ -19,24 +19,7 @@ struct migration_target_control; 
 */

#define MIGRATEPAGE_SUCCESS		0



/*

 * Keep sync with:

 * - macro MIGRATE_REASON in include/trace/events/migrate.h

 * - migrate_reason_names[MR_TYPES] in mm/debug.c

 */

enum migrate_reason {

	MR_COMPACTION,

	MR_MEMORY_FAILURE,

	MR_MEMORY_HOTPLUG,

	MR_SYSCALL,		/* also applies to cpusets */

	MR_MEMPOLICY_MBIND,

	MR_NUMA_MISPLACED,

	MR_CONTIG_RANGE,

	MR_LONGTERM_PIN,

	MR_DEMOTION,

	MR_TYPES

};



/* Defined in mm/debug.c: */

extern const char *migrate_reason_names[MR_TYPES];



#ifdef CONFIG_MIGRATION

include/linux/migrate_mode.h

+13 −0
Original line number Diff line number Diff line
@@ -19,4 +19,17 @@ enum migrate_mode { 
	MIGRATE_SYNC_NO_COPY,

};



enum migrate_reason {

	MR_COMPACTION,

	MR_MEMORY_FAILURE,

	MR_MEMORY_HOTPLUG,

	MR_SYSCALL,		/* also applies to cpusets */

	MR_MEMPOLICY_MBIND,

	MR_NUMA_MISPLACED,

	MR_CONTIG_RANGE,

	MR_LONGTERM_PIN,

	MR_DEMOTION,

	MR_TYPES

};



#endif		/* MIGRATE_MODE_H_INCLUDED */

mm/debug.c

+11 −9
Original line number Diff line number Diff line
@@ -16,17 +16,19 @@ 
#include <linux/ctype.h>



#include "internal.h"

#include <trace/events/migrate.h>



/*

 * Define EM() and EMe() so that MIGRATE_REASON from trace/events/migrate.h can

 * be used to populate migrate_reason_names[].

 */

#undef EM

#undef EMe

#define EM(a, b)	b,

#define EMe(a, b)	b



const char *migrate_reason_names[MR_TYPES] = {

	"compaction",

	"memory_failure",

	"memory_hotplug",

	"syscall_or_cpuset",

	"mempolicy_mbind",

	"numa_misplaced",

	"contig_range",

	"longterm_pin",

	"demotion",

	MIGRATE_REASON

};



const struct trace_print_flags pageflag_names[] = {