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| author | Heiko Carstens <heiko.carstens@de.ibm.com> | 2016-05-20 08:08:14 +0200 |
|---|---|---|
| committer | Martin Schwidefsky <schwidefsky@de.ibm.com> | 2016-06-13 15:58:16 +0200 |
| commit | 37cd944c8d8f406eee8e0c580f823ff66738c0af (patch) | |
| tree | bc6d06963da9d43f445b92d0e2b15b05b65c6f3c /arch/s390/mm/pageattr.c | |
| parent | bab247ff5f669216e3ed2f9a4034c540187e874c (diff) | |
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/mm/pageattr.c')
| -rw-r--r-- | arch/s390/mm/pageattr.c | 18 |
1 files changed, 18 insertions, 0 deletions
diff --git a/arch/s390/mm/pageattr.c b/arch/s390/mm/pageattr.c index 91e5e29c1f5c..ba124d9c96ba 100644 --- a/arch/s390/mm/pageattr.c +++ b/arch/s390/mm/pageattr.c @@ -40,6 +40,20 @@ void __storage_key_init_range(unsigned long start, unsigned long end) } #endif +#ifdef CONFIG_PROC_FS +atomic_long_t direct_pages_count[PG_DIRECT_MAP_MAX]; + +void arch_report_meminfo(struct seq_file *m) +{ + seq_printf(m, "DirectMap4k: %8lu kB\n", + atomic_long_read(&direct_pages_count[PG_DIRECT_MAP_4K]) << 2); + seq_printf(m, "DirectMap1M: %8lu kB\n", + atomic_long_read(&direct_pages_count[PG_DIRECT_MAP_1M]) << 10); + seq_printf(m, "DirectMap2G: %8lu kB\n", + atomic_long_read(&direct_pages_count[PG_DIRECT_MAP_2G]) << 21); +} +#endif /* CONFIG_PROC_FS */ + static void pgt_set(unsigned long *old, unsigned long new, unsigned long addr, unsigned long dtt) { @@ -114,6 +128,8 @@ static int split_pmd_page(pmd_t *pmdp, unsigned long addr) } pmd_val(new) = __pa(pt_dir) | _SEGMENT_ENTRY; pgt_set((unsigned long *)pmdp, pmd_val(new), addr, CRDTE_DTT_SEGMENT); + update_page_count(PG_DIRECT_MAP_4K, PTRS_PER_PTE); + update_page_count(PG_DIRECT_MAP_1M, -1); return 0; } @@ -181,6 +197,8 @@ static int split_pud_page(pud_t *pudp, unsigned long addr) } pud_val(new) = __pa(pm_dir) | _REGION3_ENTRY; pgt_set((unsigned long *)pudp, pud_val(new), addr, CRDTE_DTT_REGION3); + update_page_count(PG_DIRECT_MAP_1M, PTRS_PER_PMD); + update_page_count(PG_DIRECT_MAP_2G, -1); return 0; } |