1 #!/usr/bin/env drgn 1 #!/usr/bin/env drgn
2 # 2 #
3 # Copyright (C) 2020 Roman Gushchin <guro@fb.co 3 # Copyright (C) 2020 Roman Gushchin <guro@fb.com>
4 # Copyright (C) 2020 Facebook 4 # Copyright (C) 2020 Facebook
5 5
6 from os import stat 6 from os import stat
7 import argparse 7 import argparse
8 import sys 8 import sys
9 9
10 from drgn.helpers.linux import list_for_each_e 10 from drgn.helpers.linux import list_for_each_entry, list_empty
11 from drgn.helpers.linux import for_each_page 11 from drgn.helpers.linux import for_each_page
12 from drgn.helpers.linux.cpumask import for_eac 12 from drgn.helpers.linux.cpumask import for_each_online_cpu
13 from drgn.helpers.linux.percpu import per_cpu_ 13 from drgn.helpers.linux.percpu import per_cpu_ptr
14 from drgn import container_of, FaultError, Obj 14 from drgn import container_of, FaultError, Object, cast
15 15
16 16
17 DESC = """ 17 DESC = """
18 This is a drgn script to provide slab statisti 18 This is a drgn script to provide slab statistics for memory cgroups.
19 It supports cgroup v2 and v1 and can emulate m 19 It supports cgroup v2 and v1 and can emulate memory.kmem.slabinfo
20 interface of cgroup v1. 20 interface of cgroup v1.
21 For drgn, visit https://github.com/osandov/drg 21 For drgn, visit https://github.com/osandov/drgn.
22 """ 22 """
23 23
24 24
25 MEMCGS = {} 25 MEMCGS = {}
26 26
27 OO_SHIFT = 16 27 OO_SHIFT = 16
28 OO_MASK = ((1 << OO_SHIFT) - 1) 28 OO_MASK = ((1 << OO_SHIFT) - 1)
29 29
30 30
31 def err(s): 31 def err(s):
32 print('slabinfo.py: error: %s' % s, file=s 32 print('slabinfo.py: error: %s' % s, file=sys.stderr, flush=True)
33 sys.exit(1) 33 sys.exit(1)
34 34
35 35
36 def find_memcg_ids(css=prog['root_mem_cgroup'] 36 def find_memcg_ids(css=prog['root_mem_cgroup'].css, prefix=''):
37 if not list_empty(css.children.address_of_ 37 if not list_empty(css.children.address_of_()):
38 for css in list_for_each_entry('struct 38 for css in list_for_each_entry('struct cgroup_subsys_state',
39 css.chi 39 css.children.address_of_(),
40 'siblin 40 'sibling'):
41 name = prefix + '/' + css.cgroup.k 41 name = prefix + '/' + css.cgroup.kn.name.string_().decode('utf-8')
42 memcg = container_of(css, 'struct 42 memcg = container_of(css, 'struct mem_cgroup', 'css')
43 MEMCGS[css.cgroup.kn.id.value_()] 43 MEMCGS[css.cgroup.kn.id.value_()] = memcg
44 find_memcg_ids(css, name) 44 find_memcg_ids(css, name)
45 45
46 46
47 def is_root_cache(s): 47 def is_root_cache(s):
48 try: 48 try:
49 return False if s.memcg_params.root_ca 49 return False if s.memcg_params.root_cache else True
50 except AttributeError: 50 except AttributeError:
51 return True 51 return True
52 52
53 53
54 def cache_name(s): 54 def cache_name(s):
55 if is_root_cache(s): 55 if is_root_cache(s):
56 return s.name.string_().decode('utf-8' 56 return s.name.string_().decode('utf-8')
57 else: 57 else:
58 return s.memcg_params.root_cache.name. 58 return s.memcg_params.root_cache.name.string_().decode('utf-8')
59 59
60 60
61 # SLUB 61 # SLUB
62 62
63 def oo_order(s): 63 def oo_order(s):
64 return s.oo.x >> OO_SHIFT 64 return s.oo.x >> OO_SHIFT
65 65
66 66
67 def oo_objects(s): 67 def oo_objects(s):
68 return s.oo.x & OO_MASK 68 return s.oo.x & OO_MASK
69 69
70 70
71 def count_partial(n, fn): 71 def count_partial(n, fn):
72 nr_objs = 0 72 nr_objs = 0
73 for slab in list_for_each_entry('struct sl 73 for slab in list_for_each_entry('struct slab', n.partial.address_of_(),
74 'slab_list 74 'slab_list'):
75 nr_objs += fn(slab) 75 nr_objs += fn(slab)
76 return nr_objs 76 return nr_objs
77 77
78 78
79 def count_free(slab): 79 def count_free(slab):
80 return slab.objects - slab.inuse 80 return slab.objects - slab.inuse
81 81
82 82
83 def slub_get_slabinfo(s, cfg): 83 def slub_get_slabinfo(s, cfg):
84 nr_slabs = 0 84 nr_slabs = 0
85 nr_objs = 0 85 nr_objs = 0
86 nr_free = 0 86 nr_free = 0
87 87
88 for node in range(cfg['nr_nodes']): 88 for node in range(cfg['nr_nodes']):
89 n = s.node[node] 89 n = s.node[node]
90 nr_slabs += n.nr_slabs.counter.value_( 90 nr_slabs += n.nr_slabs.counter.value_()
91 nr_objs += n.total_objects.counter.val 91 nr_objs += n.total_objects.counter.value_()
92 nr_free += count_partial(n, count_free 92 nr_free += count_partial(n, count_free)
93 93
94 return {'active_objs': nr_objs - nr_free, 94 return {'active_objs': nr_objs - nr_free,
95 'num_objs': nr_objs, 95 'num_objs': nr_objs,
96 'active_slabs': nr_slabs, 96 'active_slabs': nr_slabs,
97 'num_slabs': nr_slabs, 97 'num_slabs': nr_slabs,
98 'objects_per_slab': oo_objects(s), 98 'objects_per_slab': oo_objects(s),
99 'cache_order': oo_order(s), 99 'cache_order': oo_order(s),
100 'limit': 0, 100 'limit': 0,
101 'batchcount': 0, 101 'batchcount': 0,
102 'shared': 0, 102 'shared': 0,
103 'shared_avail': 0} 103 'shared_avail': 0}
104 104
105 105
106 def cache_show(s, cfg, objs): 106 def cache_show(s, cfg, objs):
107 if cfg['allocator'] == 'SLUB': 107 if cfg['allocator'] == 'SLUB':
108 sinfo = slub_get_slabinfo(s, cfg) 108 sinfo = slub_get_slabinfo(s, cfg)
109 else: 109 else:
110 err('SLAB isn\'t supported yet') 110 err('SLAB isn\'t supported yet')
111 111
112 if cfg['shared_slab_pages']: 112 if cfg['shared_slab_pages']:
113 sinfo['active_objs'] = objs 113 sinfo['active_objs'] = objs
114 sinfo['num_objs'] = objs 114 sinfo['num_objs'] = objs
115 115
116 print('%-17s %6lu %6lu %6u %4u %4d' 116 print('%-17s %6lu %6lu %6u %4u %4d'
117 ' : tunables %4u %4u %4u' 117 ' : tunables %4u %4u %4u'
118 ' : slabdata %6lu %6lu %6lu' % ( 118 ' : slabdata %6lu %6lu %6lu' % (
119 cache_name(s), sinfo['active_obj 119 cache_name(s), sinfo['active_objs'], sinfo['num_objs'],
120 s.size, sinfo['objects_per_slab' 120 s.size, sinfo['objects_per_slab'], 1 << sinfo['cache_order'],
121 sinfo['limit'], sinfo['batchcoun 121 sinfo['limit'], sinfo['batchcount'], sinfo['shared'],
122 sinfo['active_slabs'], sinfo['nu 122 sinfo['active_slabs'], sinfo['num_slabs'],
123 sinfo['shared_avail'])) 123 sinfo['shared_avail']))
124 124
125 125
126 def detect_kernel_config(): 126 def detect_kernel_config():
127 cfg = {} 127 cfg = {}
128 128
129 cfg['nr_nodes'] = prog['nr_online_nodes']. 129 cfg['nr_nodes'] = prog['nr_online_nodes'].value_()
130 130
131 if prog.type('struct kmem_cache').members[ 131 if prog.type('struct kmem_cache').members[1].name == 'flags':
132 cfg['allocator'] = 'SLUB' 132 cfg['allocator'] = 'SLUB'
133 elif prog.type('struct kmem_cache').member 133 elif prog.type('struct kmem_cache').members[1].name == 'batchcount':
134 cfg['allocator'] = 'SLAB' 134 cfg['allocator'] = 'SLAB'
135 else: 135 else:
136 err('Can\'t determine the slab allocat 136 err('Can\'t determine the slab allocator')
137 137
138 cfg['shared_slab_pages'] = False 138 cfg['shared_slab_pages'] = False
139 try: 139 try:
140 if prog.type('struct obj_cgroup'): 140 if prog.type('struct obj_cgroup'):
141 cfg['shared_slab_pages'] = True 141 cfg['shared_slab_pages'] = True
142 except: 142 except:
143 pass 143 pass
144 144
145 return cfg 145 return cfg
146 146
147 147
148 def for_each_slab(prog): 148 def for_each_slab(prog):
149 PGSlab = ~prog.constant('PG_slab') !! 149 PGSlab = 1 << prog.constant('PG_slab')
>> 150 PGHead = 1 << prog.constant('PG_head')
150 151
151 for page in for_each_page(prog): 152 for page in for_each_page(prog):
152 try: 153 try:
153 if page.page_type.value_() == PGSl !! 154 if page.flags.value_() & PGSlab:
154 yield cast('struct slab *', pa 155 yield cast('struct slab *', page)
155 except FaultError: 156 except FaultError:
156 pass 157 pass
157 158
158 159
159 def main(): 160 def main():
160 parser = argparse.ArgumentParser(descripti 161 parser = argparse.ArgumentParser(description=DESC,
161 formatter 162 formatter_class=
162 argparse. 163 argparse.RawTextHelpFormatter)
163 parser.add_argument('cgroup', metavar='CGR 164 parser.add_argument('cgroup', metavar='CGROUP',
164 help='Target memory cg 165 help='Target memory cgroup')
165 args = parser.parse_args() 166 args = parser.parse_args()
166 167
167 try: 168 try:
168 cgroup_id = stat(args.cgroup).st_ino 169 cgroup_id = stat(args.cgroup).st_ino
169 find_memcg_ids() 170 find_memcg_ids()
170 memcg = MEMCGS[cgroup_id] 171 memcg = MEMCGS[cgroup_id]
171 except KeyError: 172 except KeyError:
172 err('Can\'t find the memory cgroup') 173 err('Can\'t find the memory cgroup')
173 174
174 cfg = detect_kernel_config() 175 cfg = detect_kernel_config()
175 176
176 print('# name <active_objs> <nu 177 print('# name <active_objs> <num_objs> <objsize> <objperslab> <pagesperslab>'
177 ' : tunables <limit> <batchcount> <s 178 ' : tunables <limit> <batchcount> <sharedfactor>'
178 ' : slabdata <active_slabs> <num_sla 179 ' : slabdata <active_slabs> <num_slabs> <sharedavail>')
179 180
180 if cfg['shared_slab_pages']: 181 if cfg['shared_slab_pages']:
181 obj_cgroups = set() 182 obj_cgroups = set()
182 stats = {} 183 stats = {}
183 caches = {} 184 caches = {}
184 185
185 # find memcg pointers belonging to the 186 # find memcg pointers belonging to the specified cgroup
186 obj_cgroups.add(memcg.objcg.value_()) 187 obj_cgroups.add(memcg.objcg.value_())
187 for ptr in list_for_each_entry('struct 188 for ptr in list_for_each_entry('struct obj_cgroup',
188 memcg.o 189 memcg.objcg_list.address_of_(),
189 'list') 190 'list'):
190 obj_cgroups.add(ptr.value_()) 191 obj_cgroups.add(ptr.value_())
191 192
192 # look over all slab folios and look f 193 # look over all slab folios and look for objects belonging
193 # to the given memory cgroup 194 # to the given memory cgroup
194 for slab in for_each_slab(prog): 195 for slab in for_each_slab(prog):
195 objcg_vec_raw = slab.memcg_data.va 196 objcg_vec_raw = slab.memcg_data.value_()
196 if objcg_vec_raw == 0: 197 if objcg_vec_raw == 0:
197 continue 198 continue
198 cache = slab.slab_cache 199 cache = slab.slab_cache
199 if not cache: 200 if not cache:
200 continue 201 continue
201 addr = cache.value_() 202 addr = cache.value_()
202 caches[addr] = cache 203 caches[addr] = cache
203 # clear the lowest bit to get the 204 # clear the lowest bit to get the true obj_cgroups
204 objcg_vec = Object(prog, 'struct o 205 objcg_vec = Object(prog, 'struct obj_cgroup **',
205 value=objcg_vec 206 value=objcg_vec_raw & ~1)
206 207
207 if addr not in stats: 208 if addr not in stats:
208 stats[addr] = 0 209 stats[addr] = 0
209 210
210 for i in range(oo_objects(cache)): 211 for i in range(oo_objects(cache)):
211 if objcg_vec[i].value_() in ob 212 if objcg_vec[i].value_() in obj_cgroups:
212 stats[addr] += 1 213 stats[addr] += 1
213 214
214 for addr in caches: 215 for addr in caches:
215 if stats[addr] > 0: 216 if stats[addr] > 0:
216 cache_show(caches[addr], cfg, 217 cache_show(caches[addr], cfg, stats[addr])
217 218
218 else: 219 else:
219 for s in list_for_each_entry('struct k 220 for s in list_for_each_entry('struct kmem_cache',
220 memcg.kme 221 memcg.kmem_caches.address_of_(),
221 'memcg_pa 222 'memcg_params.kmem_caches_node'):
222 cache_show(s, cfg, None) 223 cache_show(s, cfg, None)
223 224
224 225
225 main() 226 main()
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