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Ganesh Mahendran 0f050d997e mm/zsmalloc: add statistics support 
Keeping fragmentation of zsmalloc in a low level is our target.  But now
we still need to add the debug code in zsmalloc to get the quantitative
data.

This patch adds a new configuration CONFIG_ZSMALLOC_STAT to enable the
statistics collection for developers.  Currently only the objects
statatitics in each class are collected.  User can get the information via
debugfs.

     cat /sys/kernel/debug/zsmalloc/zram0/...

For example:

After I copied "jdk-8u25-linux-x64.tar.gz" to zram with ext4 filesystem:
 class  size obj_allocated   obj_used pages_used
     0    32             0          0          0
     1    48           256         12          3
     2    64            64         14          1
     3    80            51          7          1
     4    96           128          5          3
     5   112            73          5          2
     6   128            32          4          1
     7   144             0          0          0
     8   160             0          0          0
     9   176             0          0          0
    10   192             0          0          0
    11   208             0          0          0
    12   224             0          0          0
    13   240             0          0          0
    14   256            16          1          1
    15   272            15          9          1
    16   288             0          0          0
    17   304             0          0          0
    18   320             0          0          0
    19   336             0          0          0
    20   352             0          0          0
    21   368             0          0          0
    22   384             0          0          0
    23   400             0          0          0
    24   416             0          0          0
    25   432             0          0          0
    26   448             0          0          0
    27   464             0          0          0
    28   480             0          0          0
    29   496            33          1          4
    30   512             0          0          0
    31   528             0          0          0
    32   544             0          0          0
    33   560             0          0          0
    34   576             0          0          0
    35   592             0          0          0
    36   608             0          0          0
    37   624             0          0          0
    38   640             0          0          0
    40   672             0          0          0
    42   704             0          0          0
    43   720            17          1          3
    44   736             0          0          0
    46   768             0          0          0
    49   816             0          0          0
    51   848             0          0          0
    52   864            14          1          3
    54   896             0          0          0
    57   944            13          1          3
    58   960             0          0          0
    62  1024             4          1          1
    66  1088            15          2          4
    67  1104             0          0          0
    71  1168             0          0          0
    74  1216             0          0          0
    76  1248             0          0          0
    83  1360             3          1          1
    91  1488            11          1          4
    94  1536             0          0          0
   100  1632             5          1          2
   107  1744             0          0          0
   111  1808             9          1          4
   126  2048             4          4          2
   144  2336             7          3          4
   151  2448             0          0          0
   168  2720            15         15         10
   190  3072            28         27         21
   202  3264             0          0          0
   254  4096         36209      36209      36209

 Total               37022      36326      36288

We can calculate the overall fragentation by the last line:
    Total               37022      36326      36288
    (37022 - 36326) / 37022 = 1.87%

Also by analysing objects alocated in every class we know why we got so
low fragmentation: Most of the allocated objects is in <class 254>.  And
there is only 1 page in class 254 zspage.  So, No fragmentation will be
introduced by allocating objs in class 254.

And in future, we can collect other zsmalloc statistics as we need and
analyse them.

Signed-off-by: Ganesh Mahendran <opensource.ganesh@gmail.com>
Suggested-by: Minchan Kim <minchan@kernel.org>
Acked-by: Minchan Kim <minchan@kernel.org>
Cc: Nitin Gupta <ngupta@vflare.org>
Cc: Seth Jennings <sjennings@variantweb.net>
Cc: Dan Streetman <ddstreet@ieee.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-02-12 18:54:12 -08:00
..
backing-dev.c
balloon_compaction.c
bootmem.c
cleancache.c mm: fix cleancache debugfs directory path 2015-01-20 14:08:31 +01:00
cma.c mm: cma: fix totalcma_pages to include DT defined CMA regions 2015-02-11 17:06:03 -08:00
compaction.c mm: fix negative nr_isolated counts 2015-02-12 18:54:11 -08:00
debug-pagealloc.c
debug.c mm: account pmd page tables to the process 2015-02-11 17:06:04 -08:00
dmapool.c
early_ioremap.c
fadvise.c
failslab.c
filemap.c mm: drop vm_ops->remap_pages and generic_file_remap_pages() stub 2015-02-10 14:30:30 -08:00
filemap_xip.c mm: drop vm_ops->remap_pages and generic_file_remap_pages() stub 2015-02-10 14:30:30 -08:00
frontswap.c
gup.c mm: convert p[te|md]_numa users to p[te|md]_protnone_numa 2015-02-12 18:54:08 -08:00
highmem.c
huge_memory.c mm: numa: avoid unnecessary TLB flushes when setting NUMA hinting entries 2015-02-12 18:54:08 -08:00
hugetlb.c mm: account pmd page tables to the process 2015-02-11 17:06:04 -08:00
hugetlb_cgroup.c mm: page_counter: pull "-1" handling out of page_counter_memparse() 2015-02-11 17:06:02 -08:00
hwpoison-inject.c
init-mm.c
internal.h mm/internal.h: don't split printk call in two 2015-02-12 18:54:10 -08:00
interval_tree.c mm: replace vma->sharead.linear with vma->shared 2015-02-10 14:30:31 -08:00
iov_iter.c
Kconfig mm/zsmalloc: add statistics support 2015-02-12 18:54:12 -08:00
Kconfig.debug mm/debug_pagealloc: remove obsolete Kconfig options 2015-01-08 15:10:52 -08:00
kmemcheck.c
kmemleak-test.c
kmemleak.c
ksm.c mm: remove rest usage of VM_NONLINEAR and pte_file() 2015-02-10 14:30:31 -08:00
list_lru.c memcg: reparent list_lrus and free kmemcg_id on css offline 2015-02-12 18:54:10 -08:00
maccess.c
madvise.c mm: remove rest usage of VM_NONLINEAR and pte_file() 2015-02-10 14:30:31 -08:00
Makefile mm: replace remap_file_pages() syscall with emulation 2015-02-10 14:30:30 -08:00
memblock.c
memcontrol.c memcg: cleanup static keys decrement 2015-02-12 18:54:10 -08:00
memory-failure.c mm: hwpoison: drop lru_add_drain_all() in __soft_offline_page() 2015-02-12 18:54:11 -08:00
memory.c mm/memory.c: actually remap enough memory 2015-02-12 18:54:11 -08:00
memory_hotplug.c
mempolicy.c mm: convert p[te|md]_mknonnuma and remaining page table manipulations 2015-02-12 18:54:08 -08:00
mempool.c
migrate.c mm: convert p[te|md]_mknonnuma and remaining page table manipulations 2015-02-12 18:54:08 -08:00
mincore.c mincore: apply page table walker on do_mincore() 2015-02-11 17:06:06 -08:00
mlock.c
mm_init.c mm/mm_init.c: mark mminit_loglevel __meminitdata 2015-02-12 18:54:11 -08:00
mmap.c mm/mmap.c: fix arithmetic overflow in __vm_enough_memory() 2015-02-11 17:06:07 -08:00
mmu_context.c
mmu_notifier.c
mmzone.c mm: microoptimize zonelist operations 2015-02-11 17:06:02 -08:00
mprotect.c mm: numa: avoid unnecessary TLB flushes when setting NUMA hinting entries 2015-02-12 18:54:08 -08:00
mremap.c mm: remove rest usage of VM_NONLINEAR and pte_file() 2015-02-10 14:30:31 -08:00
msync.c mm: remove rest usage of VM_NONLINEAR and pte_file() 2015-02-10 14:30:31 -08:00
nobootmem.c
nommu.c mm/nommu.c: fix arithmetic overflow in __vm_enough_memory() 2015-02-11 17:06:07 -08:00
oom_kill.c mm: account pmd page tables to the process 2015-02-11 17:06:04 -08:00
page-writeback.c page_writeback: put account_page_redirty() after set_page_dirty() 2015-02-11 17:06:04 -08:00
page_alloc.c mm/page_alloc: fix comment 2015-02-12 18:54:11 -08:00
page_counter.c mm: page_counter: pull "-1" handling out of page_counter_memparse() 2015-02-11 17:06:02 -08:00
page_ext.c
page_io.c
page_isolation.c
page_owner.c mm/page_owner.c: remove unnecessary stack_trace field 2015-02-11 17:06:07 -08:00
pagewalk.c mm: pagewalk: fix misbehavior of walk_page_range for vma(VM_PFNMAP) 2015-02-11 17:06:06 -08:00
percpu-km.c
percpu-vm.c
percpu.c
pgtable-generic.c mm: convert p[te|md]_mknonnuma and remaining page table manipulations 2015-02-12 18:54:08 -08:00
process_vm_access.c mm: gup: use get_user_pages_unlocked 2015-02-11 17:06:05 -08:00
quicklist.c
readahead.c
rmap.c mm: memcontrol: track move_lock state internally 2015-02-11 17:06:00 -08:00
shmem.c swap: remove unused mem_cgroup_uncharge_swapcache declaration 2015-02-11 17:06:00 -08:00
slab.c slub: make dead caches discard free slabs immediately 2015-02-12 18:54:10 -08:00
slab.h slub: make dead caches discard free slabs immediately 2015-02-12 18:54:10 -08:00
slab_common.c slub: make dead caches discard free slabs immediately 2015-02-12 18:54:10 -08:00
slob.c slub: make dead caches discard free slabs immediately 2015-02-12 18:54:10 -08:00
slub.c slub: make dead caches discard free slabs immediately 2015-02-12 18:54:10 -08:00
sparse-vmemmap.c
sparse.c
swap.c rmap: drop support of non-linear mappings 2015-02-10 14:30:31 -08:00
swap_cgroup.c
swap_state.c
swapfile.c
truncate.c
util.c mm: gup: use get_user_pages_unlocked within get_user_pages_fast 2015-02-11 17:06:05 -08:00
vmacache.c
vmalloc.c
vmpressure.c
vmscan.c vmscan: per memory cgroup slab shrinkers 2015-02-12 18:54:09 -08:00
vmstat.c vmstat: Reduce time interval to stat update on idle cpu 2015-02-11 17:06:07 -08:00
workingset.c list_lru: add helpers to isolate items 2015-02-12 18:54:10 -08:00
zbud.c mm/zpool: add name argument to create zpool 2015-02-12 18:54:12 -08:00
zpool.c mm/zpool: add name argument to create zpool 2015-02-12 18:54:12 -08:00
zsmalloc.c mm/zsmalloc: add statistics support 2015-02-12 18:54:12 -08:00
zswap.c mm/zpool: add name argument to create zpool 2015-02-12 18:54:12 -08:00