# -*- Mode: python; coding: utf-8; indent-tabs-mode: nil -*- */ # # This file is part of systemd. # # Copyright 2014 Michal Schmidt # # systemd is free software; you can redistribute it and/or modify it # under the terms of the GNU Lesser General Public License as published by # the Free Software Foundation; either version 2.1 of the License, or # (at your option) any later version. # # systemd is distributed in the hope that it will be useful, but # WITHOUT ANY WARRANTY; without even the implied warranty of # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU # Lesser General Public License for more details. # # You should have received a copy of the GNU Lesser General Public License # along with systemd; If not, see <http://www.gnu.org/licenses/>. import gdb class sd_dump_hashmaps(gdb.Command): "dump systemd's hashmaps" def __init__(self): super(sd_dump_hashmaps, self).__init__("sd_dump_hashmaps", gdb.COMMAND_DATA, gdb.COMPLETE_NONE) def invoke(self, arg, from_tty): d = gdb.parse_and_eval("hashmap_debug_list") all_entry_sizes = gdb.parse_and_eval("all_entry_sizes") all_direct_buckets = gdb.parse_and_eval("all_direct_buckets") hashmap_base_t = gdb.lookup_type("HashmapBase") uchar_t = gdb.lookup_type("unsigned char") ulong_t = gdb.lookup_type("unsigned long") debug_offset = gdb.parse_and_eval("(unsigned long)&((HashmapBase*)0)->debug") print "type, hash, indirect, entries, max_entries, buckets, creator" while d: h = gdb.parse_and_eval("(HashmapBase*)((char*)%d - %d)" % (int(d.cast(ulong_t)), debug_offset)) if h["has_indirect"]: storage_ptr = h["indirect"]["storage"].cast(uchar_t.pointer()) n_entries = h["indirect"]["n_entries"] n_buckets = h["indirect"]["n_buckets"] else: storage_ptr = h["direct"]["storage"].cast(uchar_t.pointer()) n_entries = h["n_direct_entries"] n_buckets = all_direct_buckets[int(h["type"])]; t = ["plain", "ordered", "set"][int(h["type"])] print "%s, %s, %s, %d, %d, %d, %s (%s:%d)" % (t, h["hash_ops"], bool(h["has_indirect"]), n_entries, d["max_entries"], n_buckets, d["func"], d["file"], d["line"]) if arg != "" and n_entries > 0: dib_raw_addr = storage_ptr + (all_entry_sizes[h["type"]] * n_buckets) histogram = {} for i in xrange(0, n_buckets): dib = int(dib_raw_addr[i]) histogram[dib] = histogram.get(dib, 0) + 1 for dib in sorted(iter(histogram)): if dib != 255: print "%3d %8d %f%% of entries" % (dib, histogram[dib], 100.0*histogram[dib]/n_entries) else: print "%3d %8d %f%% of slots" % (dib, histogram[dib], 100.0*histogram[dib]/n_buckets) print "mean DIB of entries: %f" % (sum([dib*histogram[dib] for dib in iter(histogram) if dib != 255])*1.0/n_entries) blocks = [] current_len = 1 prev = int(dib_raw_addr[0]) for i in xrange(1, n_buckets): dib = int(dib_raw_addr[i]) if (dib == 255) != (prev == 255): if prev != 255: blocks += [[i, current_len]] current_len = 1 else: current_len += 1 prev = dib if prev != 255: blocks += [[i, current_len]] # a block may be wrapped around if len(blocks) > 1 and blocks[0][0] == blocks[0][1] and blocks[-1][0] == n_buckets - 1: blocks[0][1] += blocks[-1][1] blocks = blocks[0:-1] print "max block: %s" % max(blocks, key=lambda a: a[1]) print "sum block lens: %d" % sum(b[1] for b in blocks) print "mean block len: %f" % (1.0 * sum(b[1] for b in blocks) / len(blocks)) d = d["debug_list_next"] sd_dump_hashmaps()