From 221944736f66f38e9bdbce52c616d10df7f15c54 Mon Sep 17 00:00:00 2001 From: Roman Gushchin Date: Wed, 16 Feb 2022 12:43:30 -0800 Subject: tools/cgroup/slabinfo: update to work with struct slab After the introduction of the dedicated struct slab to describe slab pages by commit d122019bf061 ("mm: Split slab into its own type") and the following removal of the corresponding struct page's fields by commit 07f910f9b729 ("mm: Remove slab from struct page") the memcg_slabinfo tool broke. An attempt to run it produces a trace like this: Traceback (most recent call last): File "/usr/bin/drgn", line 33, in sys.exit(load_entry_point('drgn==0.0.16', 'console_scripts', 'drgn')()) File "/usr/lib64/python3.9/site-packages/drgn/internal/cli.py", line 133, in main runpy.run_path(args.script[0], init_globals=init_globals, run_name="__main__") File "/usr/lib64/python3.9/runpy.py", line 268, in run_path return _run_module_code(code, init_globals, run_name, File "/usr/lib64/python3.9/runpy.py", line 97, in _run_module_code _run_code(code, mod_globals, init_globals, File "/usr/lib64/python3.9/runpy.py", line 87, in _run_code exec(code, run_globals) File "memcg_slabinfo.py", line 226, in main() File "memcg_slabinfo.py", line 199, in main cache = page.slab_cache AttributeError: 'struct page' has no member 'slab_cache' The problem can be fixed by explicitly casting struct page * to struct slab * for slab pages. The tools works as expected with this fix, e.g.: cred_jar 776 776 192 21 1 : tunables 0 0 0 : slabdata 547 547 0 kmalloc-cg-32 6 6 32 128 1 : tunables 0 0 0 : slabdata 9 9 0 files_cache 3 3 832 39 8 : tunables 0 0 0 : slabdata 8 8 0 kmalloc-cg-512 1 1 512 32 4 : tunables 0 0 0 : slabdata 10 10 0 task_struct 10 10 6720 4 8 : tunables 0 0 0 : slabdata 63 63 0 mm_struct 3 3 1664 19 8 : tunables 0 0 0 : slabdata 9 9 0 kmalloc-cg-16 1 1 16 256 1 : tunables 0 0 0 : slabdata 8 8 0 pde_opener 1 1 40 102 1 : tunables 0 0 0 : slabdata 8 8 0 anon_vma_chain 375 375 64 64 1 : tunables 0 0 0 : slabdata 81 81 0 radix_tree_node 3 3 584 28 4 : tunables 0 0 0 : slabdata 419 419 0 dentry 98 98 312 26 2 : tunables 0 0 0 : slabdata 1420 1420 0 btrfs_inode 3 3 2368 13 8 : tunables 0 0 0 : slabdata 730 730 0 signal_cache 3 3 1600 20 8 : tunables 0 0 0 : slabdata 17 17 0 sighand_cache 3 3 2240 14 8 : tunables 0 0 0 : slabdata 20 20 0 filp 90 90 512 32 4 : tunables 0 0 0 : slabdata 95 95 0 anon_vma 214 214 200 20 1 : tunables 0 0 0 : slabdata 162 162 0 kmalloc-cg-1k 1 1 1024 32 8 : tunables 0 0 0 : slabdata 22 22 0 pid 10 10 256 32 2 : tunables 0 0 0 : slabdata 14 14 0 kmalloc-cg-64 2 2 64 64 1 : tunables 0 0 0 : slabdata 8 8 0 kmalloc-cg-96 3 3 96 42 1 : tunables 0 0 0 : slabdata 8 8 0 sock_inode_cache 5 5 1408 23 8 : tunables 0 0 0 : slabdata 29 29 0 UNIX 7 7 1920 17 8 : tunables 0 0 0 : slabdata 21 21 0 inode_cache 36 36 1152 28 8 : tunables 0 0 0 : slabdata 680 680 0 proc_inode_cache 26 26 1224 26 8 : tunables 0 0 0 : slabdata 64 64 0 kmalloc-cg-2k 2 2 2048 16 8 : tunables 0 0 0 : slabdata 9 9 0 v2: change naming and count_partial()/count_free()/for_each_slab() signatures to work with slabs, suggested by Matthew Wilcox Fixes: 07f910f9b729 ("mm: Remove slab from struct page") Reported-by: Vasily Averin Signed-off-by: Roman Gushchin Tested-by: Vasily Averin Signed-off-by: Vlastimil Babka Link: https://lore.kernel.org/linux-patches/Yg2cKKnIboNu7j+p@carbon.DHCP.thefacebook.com/ --- tools/cgroup/memcg_slabinfo.py | 30 +++++++++++++++--------------- 1 file changed, 15 insertions(+), 15 deletions(-) (limited to 'tools/cgroup') diff --git a/tools/cgroup/memcg_slabinfo.py b/tools/cgroup/memcg_slabinfo.py index 1600b17dbb8a..1d3a90d93fe2 100644 --- a/tools/cgroup/memcg_slabinfo.py +++ b/tools/cgroup/memcg_slabinfo.py @@ -11,7 +11,7 @@ from drgn.helpers.linux import list_for_each_entry, list_empty from drgn.helpers.linux import for_each_page from drgn.helpers.linux.cpumask import for_each_online_cpu from drgn.helpers.linux.percpu import per_cpu_ptr -from drgn import container_of, FaultError, Object +from drgn import container_of, FaultError, Object, cast DESC = """ @@ -69,15 +69,15 @@ def oo_objects(s): def count_partial(n, fn): - nr_pages = 0 - for page in list_for_each_entry('struct page', n.partial.address_of_(), - 'lru'): - nr_pages += fn(page) - return nr_pages + nr_objs = 0 + for slab in list_for_each_entry('struct slab', n.partial.address_of_(), + 'slab_list'): + nr_objs += fn(slab) + return nr_objs -def count_free(page): - return page.objects - page.inuse +def count_free(slab): + return slab.objects - slab.inuse def slub_get_slabinfo(s, cfg): @@ -145,14 +145,14 @@ def detect_kernel_config(): return cfg -def for_each_slab_page(prog): +def for_each_slab(prog): PGSlab = 1 << prog.constant('PG_slab') PGHead = 1 << prog.constant('PG_head') for page in for_each_page(prog): try: if page.flags.value_() & PGSlab: - yield page + yield cast('struct slab *', page) except FaultError: pass @@ -190,13 +190,13 @@ def main(): 'list'): obj_cgroups.add(ptr.value_()) - # 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.memcg_data.value_() + # look over all slab folios and look for objects belonging + # to the given memory cgroup + for slab in for_each_slab(prog): + objcg_vec_raw = slab.memcg_data.value_() if objcg_vec_raw == 0: continue - cache = page.slab_cache + cache = slab.slab_cache if not cache: continue addr = cache.value_() -- cgit v1.2.3-59-g8ed1b