2021-04-22 05:31:05

by Vasily Averin

Subject: [PATCH] tools/cgroup/slabinfo.py: updated to work on current kernel

slabinfo.py script does not work with actual kernel version.
First, it was unable to recognise SLUB susbsytem,
when I specified it manually, it was failed again with
AttributeError: 'struct page' has no member 'obj_cgroups'
... and then again with
File "tools/cgroup/memcg_slabinfo.py", line 221, in main
memcg.kmem_caches.address_of_(),
AttributeError: 'struct mem_cgroup' has no member 'kmem_caches'

Signed-off-by: Vasily Averin <[email protected]>
---
tools/cgroup/memcg_slabinfo.py | 8 ++++----
1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/tools/cgroup/memcg_slabinfo.py b/tools/cgroup/memcg_slabinfo.py
index c4225ed..1600b17 100644
--- a/tools/cgroup/memcg_slabinfo.py
+++ b/tools/cgroup/memcg_slabinfo.py
@@ -128,9 +128,9 @@ OO_MASK = ((1 << OO_SHIFT) - 1)

cfg['nr_nodes'] = prog['nr_online_nodes'].value_()

- if prog.type('struct kmem_cache').members[1][1] == 'flags':
+ if prog.type('struct kmem_cache').members[1].name == 'flags':
cfg['allocator'] = 'SLUB'
- elif prog.type('struct kmem_cache').members[1][1] == 'batchcount':
+ elif prog.type('struct kmem_cache').members[1].name == 'batchcount':
cfg['allocator'] = 'SLAB'
else:
err('Can\'t determine the slab allocator')
@@ -193,7 +193,7 @@ OO_MASK = ((1 << OO_SHIFT) - 1)
# look over all slab pages, belonging to non-root memcgs
# and look for objects belonging to the given memory cgroup
for page in for_each_slab_page(prog):
- objcg_vec_raw = page.obj_cgroups.value_()
+ objcg_vec_raw = page.memcg_data.value_()
if objcg_vec_raw == 0:
continue
cache = page.slab_cache
@@ -202,7 +202,7 @@ OO_MASK = ((1 << OO_SHIFT) - 1)
addr = cache.value_()
caches[addr] = cache
# clear the lowest bit to get the true obj_cgroups
- objcg_vec = Object(prog, page.obj_cgroups.type_,
+ objcg_vec = Object(prog, 'struct obj_cgroup **',
value=objcg_vec_raw & ~1)

if addr not in stats:
--
1.8.3.1

2021-04-23 00:54:26

by Roman Gushchin

Subject: Re: [PATCH] tools/cgroup/slabinfo.py: updated to work on current kernel

On Thu, Apr 22, 2021 at 08:29:31AM +0300, Vasily Averin wrote:
> slabinfo.py script does not work with actual kernel version.
> First, it was unable to recognise SLUB susbsytem,
> when I specified it manually, it was failed again with
> AttributeError: 'struct page' has no member 'obj_cgroups'
> ... and then again with
> File "tools/cgroup/memcg_slabinfo.py", line 221, in main
> memcg.kmem_caches.address_of_(),
> AttributeError: 'struct mem_cgroup' has no member 'kmem_caches'
>
> Signed-off-by: Vasily Averin <[email protected]>

Indeed, we forgot to update it after recent changes in page->memcg_data.
Thank you, Vasily, for updating it!

I tested it, and it works great for me. Please, feel free to add
Tested-by: Roman Gushchin <[email protected]>
Acked-by: Roman Gushchin <[email protected]>

Thanks!