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| author | Heiko Carstens <heiko.carstens@de.ibm.com> | 2016-05-20 09:08:14 +0300 |
|---|---|---|
| committer | Martin Schwidefsky <schwidefsky@de.ibm.com> | 2016-06-13 16:58:16 +0300 |
| commit | 37cd944c8d8f406eee8e0c580f823ff66738c0af (patch) | |
| tree | bc6d06963da9d43f445b92d0e2b15b05b65c6f3c /arch/s390/include/asm/pgtable.h | |
| parent | bab247ff5f669216e3ed2f9a4034c540187e874c (diff) | |
| download | linux-37cd944c8d8f406eee8e0c580f823ff66738c0af.tar.xz | |
s390/pgtable: add mapping statistics
Add statistics that show how memory is mapped within the kernel
identity mapping. This is more or less the same like git
commit ce0c0e50f94e ("x86, generic: CPA add statistics about state
of direct mapping v4") for x86.
I also intentionally copied the lower case "k" within DirectMap4k vs
the upper case "M" and "G" within the two other lines. Let's have
consistent inconsistencies across architectures.
The output of /proc/meminfo now contains these additional lines:
DirectMap4k: 2048 kB
DirectMap1M: 3991552 kB
DirectMap2G: 4194304 kB
The implementation on s390 is lockless unlike the x86 version, since I
assume changes to the kernel mapping are a very rare event. Therefore
it really doesn't matter if these statistics could potentially be
inconsistent if read while kernel pages tables are being changed.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Diffstat (limited to 'arch/s390/include/asm/pgtable.h')
| -rw-r--r-- | arch/s390/include/asm/pgtable.h | 19 |
1 files changed, 19 insertions, 0 deletions
diff --git a/arch/s390/include/asm/pgtable.h b/arch/s390/include/asm/pgtable.h index 9133388edd1f..3038edb12cad 100644 --- a/arch/s390/include/asm/pgtable.h +++ b/arch/s390/include/asm/pgtable.h @@ -28,6 +28,7 @@ #include <linux/mm_types.h> #include <linux/page-flags.h> #include <linux/radix-tree.h> +#include <linux/atomic.h> #include <asm/bug.h> #include <asm/page.h> @@ -37,6 +38,24 @@ extern void vmem_map_init(void); pmd_t *vmem_pmd_alloc(void); pte_t *vmem_pte_alloc(void); +enum { + PG_DIRECT_MAP_4K = 0, + PG_DIRECT_MAP_1M, + PG_DIRECT_MAP_2G, + PG_DIRECT_MAP_MAX +}; + +extern atomic_long_t direct_pages_count[PG_DIRECT_MAP_MAX]; + +static inline void update_page_count(int level, long count) +{ + if (IS_ENABLED(CONFIG_PROC_FS)) + atomic_long_add(count, &direct_pages_count[level]); +} + +struct seq_file; +void arch_report_meminfo(struct seq_file *m); + /* * The S390 doesn't have any external MMU info: the kernel page * tables contain all the necessary information. |