##// END OF EJS Templates
demandimport: replace more references to _demandmod instances...
demandimport: replace more references to _demandmod instances _demandmod instances may be referenced by multiple importing modules. Before this patch, the _demandmod instance only maintained a reference to its first consumer when using the "from X import Y" syntax. This is because we only created a single _demandmod instance (attached to the parent X module). If multiple modules A and B performed "from X import Y", we'd produce a single _demandmod instance "demandmod" with the following references: X.Y = <demandmod> A.Y = <demandmod> B.Y = <demandmod> The locals from the first consumer (A) would be stored in <demandmod1>. When <demandmod1> was loaded, we'd look at the locals for the first consumer and replace the symbol, if necessary. This resulted in state: X.Y = <module> A.Y = <module> B.Y = <demandmod> B's reference to Y wasn't updated and was still using the proxy object because we just didn't record that B had a reference to <demandmod> that needed updating! With this patch, we add support for tracking which modules in addition to the initial importer have a reference to the _demandmod instance and we replace those references at module load time. In the case of posix.py, this fixes an issue where the "encoding" module was being proxied, resulting in hundreds of thousands of __getattribute__ lookups on the _demandmod instance during dirstate operations on mozilla-central, speeding up execution by many milliseconds. There are likely several other operation that benefit from this change as well. The new mechanism isn't perfect: references in locals (not globals) may likely linger. So, if there is an import inside a function and a symbol from that module is used in a hot loop, we could have unwanted overhead from proxying through _demandmod. Non-global imports are discouraged anyway. So hopefully this isn't a big deal in practice. We could potentially deploy a code checker that bans use of attribute lookups of function-level-imported modules inside loops. This deficiency in theory could be avoided by storing the set of globals and locals dicts to update in the _demandmod instance. However, I tried this and it didn't work. One reason is that some globals are _demandmod instances. We could work around this, but it's a bit more work. There also might be other module import foo at play. The solution as implemented is better than what we had and IMO is good enough for the time being. It's worth noting that this sub-optimal behavior was made worse by the introduction of absolute_import and its recommended "from . import X" syntax for importing modules from the "mercurial" package. If we ever wrote performance tests, measuring the amount of module imports and __getattribute__ proxy calls through _demandmod instances would be something I'd have it check.

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verify.py
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# verify.py - repository integrity checking for Mercurial
#
# Copyright 2006, 2007 Matt Mackall <mpm@selenic.com>
#
# This software may be used and distributed according to the terms of the
# GNU General Public License version 2 or any later version.
from __future__ import absolute_import
import os
from .i18n import _
from .node import (
nullid,
short,
)
from . import (
error,
revlog,
util,
)
def verify(repo):
lock = repo.lock()
try:
return _verify(repo)
finally:
lock.release()
def _normpath(f):
# under hg < 2.4, convert didn't sanitize paths properly, so a
# converted repo may contain repeated slashes
while '//' in f:
f = f.replace('//', '/')
return f
def _verify(repo):
repo = repo.unfiltered()
mflinkrevs = {}
filelinkrevs = {}
filenodes = {}
revisions = 0
badrevs = set()
errors = [0]
warnings = [0]
ui = repo.ui
cl = repo.changelog
mf = repo.manifest
lrugetctx = util.lrucachefunc(repo.changectx)
if not repo.url().startswith('file:'):
raise util.Abort(_("cannot verify bundle or remote repos"))
def err(linkrev, msg, filename=None):
if linkrev is not None:
badrevs.add(linkrev)
else:
linkrev = '?'
msg = "%s: %s" % (linkrev, msg)
if filename:
msg = "%s@%s" % (filename, msg)
ui.warn(" " + msg + "\n")
errors[0] += 1
def exc(linkrev, msg, inst, filename=None):
if isinstance(inst, KeyboardInterrupt):
ui.warn(_("interrupted"))
raise
if not str(inst):
inst = repr(inst)
err(linkrev, "%s: %s" % (msg, inst), filename)
def warn(msg):
ui.warn(msg + "\n")
warnings[0] += 1
def checklog(obj, name, linkrev):
if not len(obj) and (havecl or havemf):
err(linkrev, _("empty or missing %s") % name)
return
d = obj.checksize()
if d[0]:
err(None, _("data length off by %d bytes") % d[0], name)
if d[1]:
err(None, _("index contains %d extra bytes") % d[1], name)
if obj.version != revlog.REVLOGV0:
if not revlogv1:
warn(_("warning: `%s' uses revlog format 1") % name)
elif revlogv1:
warn(_("warning: `%s' uses revlog format 0") % name)
def checkentry(obj, i, node, seen, linkrevs, f):
lr = obj.linkrev(obj.rev(node))
if lr < 0 or (havecl and lr not in linkrevs):
if lr < 0 or lr >= len(cl):
msg = _("rev %d points to nonexistent changeset %d")
else:
msg = _("rev %d points to unexpected changeset %d")
err(None, msg % (i, lr), f)
if linkrevs:
if f and len(linkrevs) > 1:
try:
# attempt to filter down to real linkrevs
linkrevs = [l for l in linkrevs
if lrugetctx(l)[f].filenode() == node]
except Exception:
pass
warn(_(" (expected %s)") % " ".join(map(str, linkrevs)))
lr = None # can't be trusted
try:
p1, p2 = obj.parents(node)
if p1 not in seen and p1 != nullid:
err(lr, _("unknown parent 1 %s of %s") %
(short(p1), short(node)), f)
if p2 not in seen and p2 != nullid:
err(lr, _("unknown parent 2 %s of %s") %
(short(p2), short(node)), f)
except Exception as inst:
exc(lr, _("checking parents of %s") % short(node), inst, f)
if node in seen:
err(lr, _("duplicate revision %d (%d)") % (i, seen[node]), f)
seen[node] = i
return lr
if os.path.exists(repo.sjoin("journal")):
ui.warn(_("abandoned transaction found - run hg recover\n"))
revlogv1 = cl.version != revlog.REVLOGV0
if ui.verbose or not revlogv1:
ui.status(_("repository uses revlog format %d\n") %
(revlogv1 and 1 or 0))
havecl = len(cl) > 0
havemf = len(mf) > 0
ui.status(_("checking changesets\n"))
refersmf = False
seen = {}
checklog(cl, "changelog", 0)
total = len(repo)
for i in repo:
ui.progress(_('checking'), i, total=total, unit=_('changesets'))
n = cl.node(i)
checkentry(cl, i, n, seen, [i], "changelog")
try:
changes = cl.read(n)
if changes[0] != nullid:
mflinkrevs.setdefault(changes[0], []).append(i)
refersmf = True
for f in changes[3]:
filelinkrevs.setdefault(_normpath(f), []).append(i)
except Exception as inst:
refersmf = True
exc(i, _("unpacking changeset %s") % short(n), inst)
ui.progress(_('checking'), None)
ui.status(_("checking manifests\n"))
seen = {}
if refersmf:
# Do not check manifest if there are only changelog entries with
# null manifests.
checklog(mf, "manifest", 0)
total = len(mf)
for i in mf:
ui.progress(_('checking'), i, total=total, unit=_('manifests'))
n = mf.node(i)
lr = checkentry(mf, i, n, seen, mflinkrevs.get(n, []), "manifest")
if n in mflinkrevs:
del mflinkrevs[n]
else:
err(lr, _("%s not in changesets") % short(n), "manifest")
try:
for f, fn in mf.readdelta(n).iteritems():
if not f:
err(lr, _("file without name in manifest"))
elif f != "/dev/null": # ignore this in very old repos
filenodes.setdefault(_normpath(f), {}).setdefault(fn, lr)
except Exception as inst:
exc(lr, _("reading manifest delta %s") % short(n), inst)
ui.progress(_('checking'), None)
ui.status(_("crosschecking files in changesets and manifests\n"))
total = len(mflinkrevs) + len(filelinkrevs) + len(filenodes)
count = 0
if havemf:
for c, m in sorted([(c, m) for m in mflinkrevs
for c in mflinkrevs[m]]):
count += 1
if m == nullid:
continue
ui.progress(_('crosschecking'), count, total=total)
err(c, _("changeset refers to unknown manifest %s") % short(m))
mflinkrevs = None # del is bad here due to scope issues
for f in sorted(filelinkrevs):
count += 1
ui.progress(_('crosschecking'), count, total=total)
if f not in filenodes:
lr = filelinkrevs[f][0]
err(lr, _("in changeset but not in manifest"), f)
if havecl:
for f in sorted(filenodes):
count += 1
ui.progress(_('crosschecking'), count, total=total)
if f not in filelinkrevs:
try:
fl = repo.file(f)
lr = min([fl.linkrev(fl.rev(n)) for n in filenodes[f]])
except Exception:
lr = None
err(lr, _("in manifest but not in changeset"), f)
ui.progress(_('crosschecking'), None)
ui.status(_("checking files\n"))
storefiles = set()
for f, f2, size in repo.store.datafiles():
if not f:
err(None, _("cannot decode filename '%s'") % f2)
elif size > 0 or not revlogv1:
storefiles.add(_normpath(f))
fncachewarned = False
files = sorted(set(filenodes) | set(filelinkrevs))
total = len(files)
for i, f in enumerate(files):
ui.progress(_('checking'), i, item=f, total=total)
try:
linkrevs = filelinkrevs[f]
except KeyError:
# in manifest but not in changelog
linkrevs = []
if linkrevs:
lr = linkrevs[0]
else:
lr = None
try:
fl = repo.file(f)
except error.RevlogError as e:
err(lr, _("broken revlog! (%s)") % e, f)
continue
for ff in fl.files():
try:
storefiles.remove(ff)
except KeyError:
warn(_(" warning: revlog '%s' not in fncache!") % ff)
fncachewarned = True
checklog(fl, f, lr)
seen = {}
rp = None
for i in fl:
revisions += 1
n = fl.node(i)
lr = checkentry(fl, i, n, seen, linkrevs, f)
if f in filenodes:
if havemf and n not in filenodes[f]:
err(lr, _("%s not in manifests") % (short(n)), f)
else:
del filenodes[f][n]
# verify contents
try:
l = len(fl.read(n))
rp = fl.renamed(n)
if l != fl.size(i):
if len(fl.revision(n)) != fl.size(i):
err(lr, _("unpacked size is %s, %s expected") %
(l, fl.size(i)), f)
except error.CensoredNodeError:
# experimental config: censor.policy
if ui.config("censor", "policy", "abort") == "abort":
err(lr, _("censored file data"), f)
except Exception as inst:
exc(lr, _("unpacking %s") % short(n), inst, f)
# check renames
try:
if rp:
if lr is not None and ui.verbose:
ctx = lrugetctx(lr)
found = False
for pctx in ctx.parents():
if rp[0] in pctx:
found = True
break
if not found:
warn(_("warning: copy source of '%s' not"
" in parents of %s") % (f, ctx))
fl2 = repo.file(rp[0])
if not len(fl2):
err(lr, _("empty or missing copy source revlog %s:%s")
% (rp[0], short(rp[1])), f)
elif rp[1] == nullid:
ui.note(_("warning: %s@%s: copy source"
" revision is nullid %s:%s\n")
% (f, lr, rp[0], short(rp[1])))
else:
fl2.rev(rp[1])
except Exception as inst:
exc(lr, _("checking rename of %s") % short(n), inst, f)
# cross-check
if f in filenodes:
fns = [(lr, n) for n, lr in filenodes[f].iteritems()]
for lr, node in sorted(fns):
err(lr, _("%s in manifests not found") % short(node), f)
ui.progress(_('checking'), None)
for f in storefiles:
warn(_("warning: orphan revlog '%s'") % f)
ui.status(_("%d files, %d changesets, %d total revisions\n") %
(len(files), len(cl), revisions))
if warnings[0]:
ui.warn(_("%d warnings encountered!\n") % warnings[0])
if fncachewarned:
ui.warn(_('hint: run "hg debugrebuildfncache" to recover from '
'corrupt fncache\n'))
if errors[0]:
ui.warn(_("%d integrity errors encountered!\n") % errors[0])
if badrevs:
ui.warn(_("(first damaged changeset appears to be %d)\n")
% min(badrevs))
return 1