From: John Hubbard <jhubbard@nvidia.com>
Date: Fri, 5 Nov 2021 13:43:32 -0700
Subject: mm/migrate: de-duplicate migrate_reason strings
Git-commit: 8eb42beac8d369f5443addd469879d152422a28d
Patch-mainline: v5.16-rc1
References: jsc#PED-1247
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: John Hubbard <jhubbard@nvidia.com>
Reviewed-by: Weizhao Ouyang <o451686892@gmail.com>
Cc: "Huang, Ying" <ying.huang@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
---
include/linux/migrate.h | 19 +------------------
include/linux/migrate_mode.h | 13 +++++++++++++
mm/debug.c | 20 +++++++++++---------
3 files changed, 25 insertions(+), 27 deletions(-)
--- a/include/linux/migrate.h
+++ b/include/linux/migrate.h
@@ -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
--- a/include/linux/migrate_mode.h
+++ b/include/linux/migrate_mode.h
@@ -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 */
--- a/mm/debug.c
+++ b/mm/debug.c
@@ -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[] = {