1 # SPDX-License-Identifier: GPL-2.0
2 #
3 # Copyright (c) 2023 MediaTek Inc.
4 #
5 # Authors:
6 # Kuan-Ying Lee <Kuan-Ying.Lee@mediatek.com>
7 #
8
9 import gdb
10 import re
11 import traceback
12 from linux import lists, utils, stackdepot, constants, mm
13
14 SLAB_RED_ZONE = constants.LX_SLAB_RED_ZONE
15 SLAB_POISON = constants.LX_SLAB_POISON
16 SLAB_KMALLOC = constants.LX_SLAB_KMALLOC
17 SLAB_HWCACHE_ALIGN = constants.LX_SLAB_HWCACHE_ALIGN
18 SLAB_CACHE_DMA = constants.LX_SLAB_CACHE_DMA
19 SLAB_CACHE_DMA32 = constants.LX_SLAB_CACHE_DMA32
20 SLAB_STORE_USER = constants.LX_SLAB_STORE_USER
21 SLAB_PANIC = constants.LX_SLAB_PANIC
22
23 OO_SHIFT = 16
24 OO_MASK = (1 << OO_SHIFT) - 1
25
26 if constants.LX_CONFIG_SLUB_DEBUG:
27 slab_type = utils.CachedType("struct slab")
28 slab_ptr_type = slab_type.get_type().pointer()
29 kmem_cache_type = utils.CachedType("struct kmem_cache")
30 kmem_cache_ptr_type = kmem_cache_type.get_type().pointer()
31 freeptr_t = utils.CachedType("freeptr_t")
32 freeptr_t_ptr = freeptr_t.get_type().pointer()
33
34 track_type = gdb.lookup_type('struct track')
35 track_alloc = int(gdb.parse_and_eval('TRACK_ALLOC'))
36 track_free = int(gdb.parse_and_eval('TRACK_FREE'))
37
38 def slab_folio(slab):
39 return slab.cast(gdb.lookup_type("struct folio").pointer())
40
41 def slab_address(slab):
42 p_ops = mm.page_ops().ops
43 folio = slab_folio(slab)
44 return p_ops.folio_address(folio)
45
46 def for_each_object(cache, addr, slab_objects):
47 p = addr
48 if cache['flags'] & SLAB_RED_ZONE:
49 p += int(cache['red_left_pad'])
50 while p < addr + (slab_objects * cache['size']):
51 yield p
52 p = p + int(cache['size'])
53
54 def get_info_end(cache):
55 if (cache['offset'] >= cache['inuse']):
56 return cache['inuse'] + gdb.lookup_type("void").pointer().sizeof
57 else:
58 return cache['inuse']
59
60 def get_orig_size(cache, obj):
61 if cache['flags'] & SLAB_STORE_USER and cache['flags'] & SLAB_KMALLOC:
62 p = mm.page_ops().ops.kasan_reset_tag(obj)
63 p += get_info_end(cache)
64 p += gdb.lookup_type('struct track').sizeof * 2
65 p = p.cast(utils.get_uint_type().pointer())
66 return p.dereference()
67 else:
68 return cache['object_size']
69
70 def get_track(cache, object_pointer, alloc):
71 p = object_pointer + get_info_end(cache)
72 p += (alloc * track_type.sizeof)
73 return p
74
75 def oo_objects(x):
76 return int(x['x']) & OO_MASK
77
78 def oo_order(x):
79 return int(x['x']) >> OO_SHIFT
80
81 def reciprocal_divide(a, R):
82 t = (a * int(R['m'])) >> 32
83 return (t + ((a - t) >> int(R['sh1']))) >> int(R['sh2'])
84
85 def __obj_to_index(cache, addr, obj):
86 return reciprocal_divide(int(mm.page_ops().ops.kasan_reset_tag(obj)) - addr, cache['reciprocal_size'])
87
88 def swab64(x):
89 result = (((x & 0x00000000000000ff) << 56) | \
90 ((x & 0x000000000000ff00) << 40) | \
91 ((x & 0x0000000000ff0000) << 24) | \
92 ((x & 0x00000000ff000000) << 8) | \
93 ((x & 0x000000ff00000000) >> 8) | \
94 ((x & 0x0000ff0000000000) >> 24) | \
95 ((x & 0x00ff000000000000) >> 40) | \
96 ((x & 0xff00000000000000) >> 56))
97 return result
98
99 def freelist_ptr_decode(cache, ptr, ptr_addr):
100 if constants.LX_CONFIG_SLAB_FREELIST_HARDENED:
101 return ptr['v'] ^ cache['random'] ^ swab64(int(ptr_addr))
102 else:
103 return ptr['v']
104
105 def get_freepointer(cache, obj):
106 obj = mm.page_ops().ops.kasan_reset_tag(obj)
107 ptr_addr = obj + cache['offset']
108 p = ptr_addr.cast(freeptr_t_ptr).dereference()
109 return freelist_ptr_decode(cache, p, ptr_addr)
110
111 def loc_exist(loc_track, addr, handle, waste):
112 for loc in loc_track:
113 if loc['addr'] == addr and loc['handle'] == handle and loc['waste'] == waste:
114 return loc
115 return None
116
117 def add_location(loc_track, cache, track, orig_size):
118 jiffies = gdb.parse_and_eval("jiffies_64")
119 age = jiffies - track['when']
120 handle = 0
121 waste = cache['object_size'] - int(orig_size)
122 pid = int(track['pid'])
123 cpuid = int(track['cpu'])
124 addr = track['addr']
125 if constants.LX_CONFIG_STACKDEPOT:
126 handle = track['handle']
127
128 loc = loc_exist(loc_track, addr, handle, waste)
129 if loc:
130 loc['count'] += 1
131 if track['when']:
132 loc['sum_time'] += age
133 loc['min_time'] = min(loc['min_time'], age)
134 loc['max_time'] = max(loc['max_time'], age)
135 loc['min_pid'] = min(loc['min_pid'], pid)
136 loc['max_pid'] = max(loc['max_pid'], pid)
137 loc['cpus'].add(cpuid)
138 else:
139 loc_track.append({
140 'count' : 1,
141 'addr' : addr,
142 'sum_time' : age,
143 'min_time' : age,
144 'max_time' : age,
145 'min_pid' : pid,
146 'max_pid' : pid,
147 'handle' : handle,
148 'waste' : waste,
149 'cpus' : {cpuid}
150 }
151 )
152
153 def slabtrace(alloc, cache_name):
154
155 def __fill_map(obj_map, cache, slab):
156 p = slab['freelist']
157 addr = slab_address(slab)
158 while p != gdb.Value(0):
159 index = __obj_to_index(cache, addr, p)
160 obj_map[index] = True # free objects
161 p = get_freepointer(cache, p)
162
163 # process every slab page on the slab_list (partial and full list)
164 def process_slab(loc_track, slab_list, alloc, cache):
165 for slab in lists.list_for_each_entry(slab_list, slab_ptr_type, "slab_list"):
166 obj_map[:] = [False] * oo_objects(cache['oo'])
167 __fill_map(obj_map, cache, slab)
168 addr = slab_address(slab)
169 for object_pointer in for_each_object(cache, addr, slab['objects']):
170 if obj_map[__obj_to_index(cache, addr, object_pointer)] == True:
171 continue
172 p = get_track(cache, object_pointer, alloc)
173 track = gdb.Value(p).cast(track_type.pointer())
174 if alloc == track_alloc:
175 size = get_orig_size(cache, object_pointer)
176 else:
177 size = cache['object_size']
178 add_location(loc_track, cache, track, size)
179 continue
180
181 slab_caches = gdb.parse_and_eval("slab_caches")
182 if mm.page_ops().ops.MAX_NUMNODES > 1:
183 nr_node_ids = int(gdb.parse_and_eval("nr_node_ids"))
184 else:
185 nr_node_ids = 1
186
187 target_cache = None
188 loc_track = []
189
190 for cache in lists.list_for_each_entry(slab_caches, kmem_cache_ptr_type, 'list'):
191 if cache['name'].string() == cache_name:
192 target_cache = cache
193 break
194
195 obj_map = [False] * oo_objects(target_cache['oo'])
196
197 if target_cache['flags'] & SLAB_STORE_USER:
198 for i in range(0, nr_node_ids):
199 cache_node = target_cache['node'][i]
200 if cache_node['nr_slabs']['counter'] == 0:
201 continue
202 process_slab(loc_track, cache_node['partial'], alloc, target_cache)
203 process_slab(loc_track, cache_node['full'], alloc, target_cache)
204 else:
205 raise gdb.GdbError("SLAB_STORE_USER is not set in %s" % target_cache['name'].string())
206
207 for loc in sorted(loc_track, key=lambda x:x['count'], reverse=True):
208 if loc['addr']:
209 addr = loc['addr'].cast(utils.get_ulong_type().pointer())
210 gdb.write("%d %s" % (loc['count'], str(addr).split(' ')[-1]))
211 else:
212 gdb.write("%d <not-available>" % loc['count'])
213
214 if loc['waste']:
215 gdb.write(" waste=%d/%d" % (loc['count'] * loc['waste'], loc['waste']))
216
217 if loc['sum_time'] != loc['min_time']:
218 gdb.write(" age=%d/%d/%d" % (loc['min_time'], loc['sum_time']/loc['count'], loc['max_time']))
219 else:
220 gdb.write(" age=%d" % loc['min_time'])
221
222 if loc['min_pid'] != loc['max_pid']:
223 gdb.write(" pid=%d-%d" % (loc['min_pid'], loc['max_pid']))
224 else:
225 gdb.write(" pid=%d" % loc['min_pid'])
226
227 if constants.LX_NR_CPUS > 1:
228 nr_cpu = gdb.parse_and_eval('__num_online_cpus')['counter']
229 if nr_cpu > 1:
230 gdb.write(" cpus=")
231 gdb.write(','.join(str(cpu) for cpu in loc['cpus']))
232 gdb.write("\n")
233 if constants.LX_CONFIG_STACKDEPOT:
234 if loc['handle']:
235 stackdepot.stack_depot_print(loc['handle'])
236 gdb.write("\n")
237
238 def help():
239 t = """Usage: lx-slabtrace --cache_name [cache_name] [Options]
240 Options:
241 --alloc
242 print information of allocation trace of the allocated objects
243 --free
244 print information of freeing trace of the allocated objects
245 Example:
246 lx-slabtrace --cache_name kmalloc-1k --alloc
247 lx-slabtrace --cache_name kmalloc-1k --free\n"""
248 gdb.write("Unrecognized command\n")
249 raise gdb.GdbError(t)
250
251 class LxSlabTrace(gdb.Command):
252 """Show specific cache slabtrace"""
253
254 def __init__(self):
255 super(LxSlabTrace, self).__init__("lx-slabtrace", gdb.COMMAND_DATA)
256
257 def invoke(self, arg, from_tty):
258 if not constants.LX_CONFIG_SLUB_DEBUG:
259 raise gdb.GdbError("CONFIG_SLUB_DEBUG is not enabled")
260
261 argv = gdb.string_to_argv(arg)
262 alloc = track_alloc # default show alloc_traces
263
264 if len(argv) == 3:
265 if argv[2] == '--alloc':
266 alloc = track_alloc
267 elif argv[2] == '--free':
268 alloc = track_free
269 else:
270 help()
271 if len(argv) >= 2 and argv[0] == '--cache_name':
272 slabtrace(alloc, argv[1])
273 else:
274 help()
275 LxSlabTrace()
276
277 def slabinfo():
278 nr_node_ids = None
279
280 if not constants.LX_CONFIG_SLUB_DEBUG:
281 raise gdb.GdbError("CONFIG_SLUB_DEBUG is not enabled")
282
283 def count_free(slab):
284 total_free = 0
285 for slab in lists.list_for_each_entry(slab, slab_ptr_type, 'slab_list'):
286 total_free += int(slab['objects'] - slab['inuse'])
287 return total_free
288
289 gdb.write("{:^18} | {:^20} | {:^12} | {:^12} | {:^8} | {:^11} | {:^13}\n".format('Pointer', 'name', 'active_objs', 'num_objs', 'objsize', 'objperslab', 'pagesperslab'))
290 gdb.write("{:-^18} | {:-^20} | {:-^12} | {:-^12} | {:-^8} | {:-^11} | {:-^13}\n".format('', '', '', '', '', '', ''))
291
292 slab_caches = gdb.parse_and_eval("slab_caches")
293 if mm.page_ops().ops.MAX_NUMNODES > 1:
294 nr_node_ids = int(gdb.parse_and_eval("nr_node_ids"))
295 else:
296 nr_node_ids = 1
297
298 for cache in lists.list_for_each_entry(slab_caches, kmem_cache_ptr_type, 'list'):
299 nr_objs = 0
300 nr_free = 0
301 nr_slabs = 0
302 for i in range(0, nr_node_ids):
303 cache_node = cache['node'][i]
304 try:
305 nr_slabs += cache_node['nr_slabs']['counter']
306 nr_objs = int(cache_node['total_objects']['counter'])
307 nr_free = count_free(cache_node['partial'])
308 except:
309 raise gdb.GdbError(traceback.format_exc())
310 active_objs = nr_objs - nr_free
311 num_objs = nr_objs
312 active_slabs = nr_slabs
313 objects_per_slab = oo_objects(cache['oo'])
314 cache_order = oo_order(cache['oo'])
315 gdb.write("{:18s} | {:20.19s} | {:12} | {:12} | {:8} | {:11} | {:13}\n".format(hex(cache), cache['name'].string(), str(active_objs), str(num_objs), str(cache['size']), str(objects_per_slab), str(1 << cache_order)))
316
317 class LxSlabInfo(gdb.Command):
318 """Show slabinfo"""
319
320 def __init__(self):
321 super(LxSlabInfo, self).__init__("lx-slabinfo", gdb.COMMAND_DATA)
322
323 def invoke(self, arg, from_tty):
324 slabinfo()
325 LxSlabInfo()
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