##// END OF EJS Templates
procutil: avoid using os.fork() to implement runbgcommand...
procutil: avoid using os.fork() to implement runbgcommand We ran into the following deadlock: - some command creates an ssh peer, then raises without explicitly closing the peer (hg id + extension in our case) - dispatch catches the exception, calls ui.log('commandfinish', ..) (the sshpeer is still not closed), which calls logtoprocess, which calls procutil.runbgcommand. - in the child of runbgcommand's fork(), between the fork and the exec, the opening of file descriptors triggers a gc which runs the destructor for sshpeer, which waits on ssh's stderr being closed, which never happens since ssh's stderr is held open by the parent of the fork where said destructor hasn't run Remotefilelog appears to have a hack around this deadlock as well. I don't know if there's more subtlety to it, because even though the problem is determistic, it is very fragile, so I didn't manage to reduce it. I can imagine three ways of tackling this problem: 1. don't run any python between fork and exec in runbgcommand 2. make the finalizer harmless after the fork 3. close the peer without relying on gc behavior This commit goes with 1, as forking without exec'ing is tricky in general in a language with gc finalizers. And maybe it's better in the presence of rust threads. A future commit will try 2 or 3. Performance wise: at low memory usage, it's an improvement. At higher memory usage, it's about 2x faster than before when ensurestart=True, but 2x slower when ensurestart=False. Not sure if that matters. The reason for that last bit is that the subprocess.Popen always waits for the execve to finish, and at high memory usage, execve is slow because it deallocates the large page table. Numbers and script: before after mem=1.0GB, ensurestart=True 52.1ms 26.0ms mem=1.0GB, ensurestart=False 14.7ms 26.0ms mem=0.5GB, ensurestart=True 23.2ms 11.2ms mem=0.5GB, ensurestart=False 6.2ms 11.3ms mem=0.2GB, ensurestart=True 15.7ms 7.4ms mem=0.2GB, ensurestart=False 4.3ms 8.1ms mem=0.0GB, ensurestart=True 2.3ms 0.7ms mem=0.0GB, ensurestart=False 0.8ms 0.8ms import time for memsize in [1_000_000_000, 500_000_000, 250_000_000, 0]: mem = 'a' * memsize for ensurestart in [True, False]: now = time.time() n = 100 for i in range(n): procutil.runbgcommand([b'true'], {}, ensurestart=ensurestart) after = time.time() ms = (after - now) / float(n) * 1000 print(f'mem={memsize / 1e9:.1f}GB, ensurestart={ensurestart} -> {ms:.1f}ms') Differential Revision: https://phab.mercurial-scm.org/D9019

File last commit:

r47575:d4ba4d51 default
r47651:8759e22f default
Show More
hgwebdir_mod.py
577 lines | 19.1 KiB | text/x-python | PythonLexer
# hgweb/hgwebdir_mod.py - Web interface for a directory of repositories.
#
# Copyright 21 May 2005 - (c) 2005 Jake Edge <jake@edge2.net>
# Copyright 2005, 2006 Olivia Mackall <olivia@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 gc
import os
import time
from ..i18n import _
from .common import (
ErrorResponse,
HTTP_SERVER_ERROR,
cspvalues,
get_contact,
get_mtime,
ismember,
paritygen,
staticfile,
statusmessage,
)
from .. import (
configitems,
encoding,
error,
extensions,
hg,
pathutil,
profiling,
pycompat,
rcutil,
registrar,
scmutil,
templater,
templateutil,
ui as uimod,
util,
)
from . import (
hgweb_mod,
request as requestmod,
webutil,
wsgicgi,
)
from ..utils import dateutil
def cleannames(items):
return [(util.pconvert(name).strip(b'/'), path) for name, path in items]
def findrepos(paths):
repos = []
for prefix, root in cleannames(paths):
roothead, roottail = os.path.split(root)
# "foo = /bar/*" or "foo = /bar/**" lets every repo /bar/N in or below
# /bar/ be served as as foo/N .
# '*' will not search inside dirs with .hg (except .hg/patches),
# '**' will search inside dirs with .hg (and thus also find subrepos).
try:
recurse = {b'*': False, b'**': True}[roottail]
except KeyError:
repos.append((prefix, root))
continue
roothead = os.path.normpath(os.path.abspath(roothead))
paths = scmutil.walkrepos(roothead, followsym=True, recurse=recurse)
repos.extend(urlrepos(prefix, roothead, paths))
return repos
def urlrepos(prefix, roothead, paths):
"""yield url paths and filesystem paths from a list of repo paths
>>> conv = lambda seq: [(v, util.pconvert(p)) for v,p in seq]
>>> conv(urlrepos(b'hg', b'/opt', [b'/opt/r', b'/opt/r/r', b'/opt']))
[('hg/r', '/opt/r'), ('hg/r/r', '/opt/r/r'), ('hg', '/opt')]
>>> conv(urlrepos(b'', b'/opt', [b'/opt/r', b'/opt/r/r', b'/opt']))
[('r', '/opt/r'), ('r/r', '/opt/r/r'), ('', '/opt')]
"""
for path in paths:
path = os.path.normpath(path)
yield (
prefix + b'/' + util.pconvert(path[len(roothead) :]).lstrip(b'/')
).strip(b'/'), path
def readallowed(ui, req):
"""Check allow_read and deny_read config options of a repo's ui object
to determine user permissions. By default, with neither option set (or
both empty), allow all users to read the repo. There are two ways a
user can be denied read access: (1) deny_read is not empty, and the
user is unauthenticated or deny_read contains user (or *), and (2)
allow_read is not empty and the user is not in allow_read. Return True
if user is allowed to read the repo, else return False."""
user = req.remoteuser
deny_read = ui.configlist(b'web', b'deny_read', untrusted=True)
if deny_read and (not user or ismember(ui, user, deny_read)):
return False
allow_read = ui.configlist(b'web', b'allow_read', untrusted=True)
# by default, allow reading if no allow_read option has been set
if not allow_read or ismember(ui, user, allow_read):
return True
return False
def rawindexentries(ui, repos, req, subdir=b''):
descend = ui.configbool(b'web', b'descend')
collapse = ui.configbool(b'web', b'collapse')
seenrepos = set()
seendirs = set()
for name, path in repos:
if not name.startswith(subdir):
continue
name = name[len(subdir) :]
directory = False
if b'/' in name:
if not descend:
continue
nameparts = name.split(b'/')
rootname = nameparts[0]
if not collapse:
pass
elif rootname in seendirs:
continue
elif rootname in seenrepos:
pass
else:
directory = True
name = rootname
# redefine the path to refer to the directory
discarded = b'/'.join(nameparts[1:])
# remove name parts plus accompanying slash
path = path[: -len(discarded) - 1]
try:
hg.repository(ui, path)
directory = False
except (IOError, error.RepoError):
pass
parts = [
req.apppath.strip(b'/'),
subdir.strip(b'/'),
name.strip(b'/'),
]
url = b'/' + b'/'.join(p for p in parts if p) + b'/'
# show either a directory entry or a repository
if directory:
# get the directory's time information
try:
d = (get_mtime(path), dateutil.makedate()[1])
except OSError:
continue
# add '/' to the name to make it obvious that
# the entry is a directory, not a regular repository
row = {
b'contact': b"",
b'contact_sort': b"",
b'name': name + b'/',
b'name_sort': name,
b'url': url,
b'description': b"",
b'description_sort': b"",
b'lastchange': d,
b'lastchange_sort': d[1] - d[0],
b'archives': templateutil.mappinglist([]),
b'isdirectory': True,
b'labels': templateutil.hybridlist([], name=b'label'),
}
seendirs.add(name)
yield row
continue
u = ui.copy()
if rcutil.use_repo_hgrc():
try:
u.readconfig(os.path.join(path, b'.hg', b'hgrc'))
except Exception as e:
u.warn(_(b'error reading %s/.hg/hgrc: %s\n') % (path, e))
continue
def get(section, name, default=uimod._unset):
return u.config(section, name, default, untrusted=True)
if u.configbool(b"web", b"hidden", untrusted=True):
continue
if not readallowed(u, req):
continue
# update time with local timezone
try:
r = hg.repository(ui, path)
except IOError:
u.warn(_(b'error accessing repository at %s\n') % path)
continue
except error.RepoError:
u.warn(_(b'error accessing repository at %s\n') % path)
continue
try:
d = (get_mtime(r.spath), dateutil.makedate()[1])
except OSError:
continue
contact = get_contact(get)
description = get(b"web", b"description")
seenrepos.add(name)
name = get(b"web", b"name", name)
labels = u.configlist(b'web', b'labels', untrusted=True)
row = {
b'contact': contact or b"unknown",
b'contact_sort': contact.upper() or b"unknown",
b'name': name,
b'name_sort': name,
b'url': url,
b'description': description or b"unknown",
b'description_sort': description.upper() or b"unknown",
b'lastchange': d,
b'lastchange_sort': d[1] - d[0],
b'archives': webutil.archivelist(u, b"tip", url),
b'isdirectory': None,
b'labels': templateutil.hybridlist(labels, name=b'label'),
}
yield row
def _indexentriesgen(
context, ui, repos, req, stripecount, sortcolumn, descending, subdir
):
rows = rawindexentries(ui, repos, req, subdir=subdir)
sortdefault = None, False
if sortcolumn and sortdefault != (sortcolumn, descending):
sortkey = b'%s_sort' % sortcolumn
rows = sorted(rows, key=lambda x: x[sortkey], reverse=descending)
for row, parity in zip(rows, paritygen(stripecount)):
row[b'parity'] = parity
yield row
def indexentries(
ui, repos, req, stripecount, sortcolumn=b'', descending=False, subdir=b''
):
args = (ui, repos, req, stripecount, sortcolumn, descending, subdir)
return templateutil.mappinggenerator(_indexentriesgen, args=args)
class hgwebdir(object):
"""HTTP server for multiple repositories.
Given a configuration, different repositories will be served depending
on the request path.
Instances are typically used as WSGI applications.
"""
def __init__(self, conf, baseui=None):
self.conf = conf
self.baseui = baseui
self.ui = None
self.lastrefresh = 0
self.motd = None
self.refresh()
if not baseui:
# set up environment for new ui
extensions.loadall(self.ui)
extensions.populateui(self.ui)
def refresh(self):
if self.ui:
refreshinterval = self.ui.configint(b'web', b'refreshinterval')
else:
item = configitems.coreitems[b'web'][b'refreshinterval']
refreshinterval = item.default
# refreshinterval <= 0 means to always refresh.
if (
refreshinterval > 0
and self.lastrefresh + refreshinterval > time.time()
):
return
if self.baseui:
u = self.baseui.copy()
else:
u = uimod.ui.load()
u.setconfig(b'ui', b'report_untrusted', b'off', b'hgwebdir')
u.setconfig(b'ui', b'nontty', b'true', b'hgwebdir')
# displaying bundling progress bar while serving feels wrong and may
# break some wsgi implementations.
u.setconfig(b'progress', b'disable', b'true', b'hgweb')
if not isinstance(self.conf, (dict, list, tuple)):
map = {b'paths': b'hgweb-paths'}
if not os.path.exists(self.conf):
raise error.Abort(_(b'config file %s not found!') % self.conf)
u.readconfig(self.conf, remap=map, trust=True)
paths = []
for name, ignored in u.configitems(b'hgweb-paths'):
for path in u.configlist(b'hgweb-paths', name):
paths.append((name, path))
elif isinstance(self.conf, (list, tuple)):
paths = self.conf
elif isinstance(self.conf, dict):
paths = self.conf.items()
extensions.populateui(u)
repos = findrepos(paths)
for prefix, root in u.configitems(b'collections'):
prefix = util.pconvert(prefix)
for path in scmutil.walkrepos(root, followsym=True):
repo = os.path.normpath(path)
name = util.pconvert(repo)
if name.startswith(prefix):
name = name[len(prefix) :]
repos.append((name.lstrip(b'/'), repo))
self.repos = repos
self.ui = u
encoding.encoding = self.ui.config(b'web', b'encoding')
self.style = self.ui.config(b'web', b'style')
self.templatepath = self.ui.config(
b'web', b'templates', untrusted=False
)
self.stripecount = self.ui.config(b'web', b'stripes')
if self.stripecount:
self.stripecount = int(self.stripecount)
prefix = self.ui.config(b'web', b'prefix')
if prefix.startswith(b'/'):
prefix = prefix[1:]
if prefix.endswith(b'/'):
prefix = prefix[:-1]
self.prefix = prefix
self.lastrefresh = time.time()
def run(self):
if not encoding.environ.get(b'GATEWAY_INTERFACE', b'').startswith(
b"CGI/1."
):
raise RuntimeError(
b"This function is only intended to be "
b"called while running as a CGI script."
)
wsgicgi.launch(self)
def __call__(self, env, respond):
baseurl = self.ui.config(b'web', b'baseurl')
req = requestmod.parserequestfromenv(env, altbaseurl=baseurl)
res = requestmod.wsgiresponse(req, respond)
return self.run_wsgi(req, res)
def run_wsgi(self, req, res):
profile = self.ui.configbool(b'profiling', b'enabled')
with profiling.profile(self.ui, enabled=profile):
try:
for r in self._runwsgi(req, res):
yield r
finally:
# There are known cycles in localrepository that prevent
# those objects (and tons of held references) from being
# collected through normal refcounting. We mitigate those
# leaks by performing an explicit GC on every request.
# TODO remove this once leaks are fixed.
# TODO only run this on requests that create localrepository
# instances instead of every request.
gc.collect()
def _runwsgi(self, req, res):
try:
self.refresh()
csp, nonce = cspvalues(self.ui)
if csp:
res.headers[b'Content-Security-Policy'] = csp
virtual = req.dispatchpath.strip(b'/')
tmpl = self.templater(req, nonce)
ctype = tmpl.render(b'mimetype', {b'encoding': encoding.encoding})
# Global defaults. These can be overridden by any handler.
res.status = b'200 Script output follows'
res.headers[b'Content-Type'] = ctype
# a static file
if virtual.startswith(b'static/') or b'static' in req.qsparams:
if virtual.startswith(b'static/'):
fname = virtual[7:]
else:
fname = req.qsparams[b'static']
static = self.ui.config(b"web", b"static", untrusted=False)
staticfile(self.templatepath, static, fname, res)
return res.sendresponse()
# top-level index
repos = dict(self.repos)
if (not virtual or virtual == b'index') and virtual not in repos:
return self.makeindex(req, res, tmpl)
# nested indexes and hgwebs
if virtual.endswith(b'/index') and virtual not in repos:
subdir = virtual[: -len(b'index')]
if any(r.startswith(subdir) for r in repos):
return self.makeindex(req, res, tmpl, subdir)
def _virtualdirs():
# Check the full virtual path, and each parent
yield virtual
for p in pathutil.finddirs(virtual):
yield p
for virtualrepo in _virtualdirs():
real = repos.get(virtualrepo)
if real:
# Re-parse the WSGI environment to take into account our
# repository path component.
uenv = req.rawenv
if pycompat.ispy3:
uenv = {
k.decode('latin1'): v
for k, v in pycompat.iteritems(uenv)
}
req = requestmod.parserequestfromenv(
uenv,
reponame=virtualrepo,
altbaseurl=self.ui.config(b'web', b'baseurl'),
# Reuse wrapped body file object otherwise state
# tracking can get confused.
bodyfh=req.bodyfh,
)
try:
# ensure caller gets private copy of ui
repo = hg.repository(self.ui.copy(), real)
return hgweb_mod.hgweb(repo).run_wsgi(req, res)
except IOError as inst:
msg = encoding.strtolocal(inst.strerror)
raise ErrorResponse(HTTP_SERVER_ERROR, msg)
except error.RepoError as inst:
raise ErrorResponse(HTTP_SERVER_ERROR, bytes(inst))
# browse subdirectories
subdir = virtual + b'/'
if [r for r in repos if r.startswith(subdir)]:
return self.makeindex(req, res, tmpl, subdir)
# prefixes not found
res.status = b'404 Not Found'
res.setbodygen(tmpl.generate(b'notfound', {b'repo': virtual}))
return res.sendresponse()
except ErrorResponse as e:
res.status = statusmessage(e.code, pycompat.bytestr(e))
res.setbodygen(
tmpl.generate(b'error', {b'error': e.message or b''})
)
return res.sendresponse()
finally:
del tmpl
def makeindex(self, req, res, tmpl, subdir=b""):
self.refresh()
sortable = [b"name", b"description", b"contact", b"lastchange"]
sortcolumn, descending = None, False
if b'sort' in req.qsparams:
sortcolumn = req.qsparams[b'sort']
descending = sortcolumn.startswith(b'-')
if descending:
sortcolumn = sortcolumn[1:]
if sortcolumn not in sortable:
sortcolumn = b""
sort = [
(
b"sort_%s" % column,
b"%s%s"
% (
(not descending and column == sortcolumn) and b"-" or b"",
column,
),
)
for column in sortable
]
self.refresh()
entries = indexentries(
self.ui,
self.repos,
req,
self.stripecount,
sortcolumn=sortcolumn,
descending=descending,
subdir=subdir,
)
mapping = {
b'entries': entries,
b'subdir': subdir,
b'pathdef': hgweb_mod.makebreadcrumb(b'/' + subdir, self.prefix),
b'sortcolumn': sortcolumn,
b'descending': descending,
}
mapping.update(sort)
res.setbodygen(tmpl.generate(b'index', mapping))
return res.sendresponse()
def templater(self, req, nonce):
def config(*args, **kwargs):
kwargs.setdefault('untrusted', True)
return self.ui.config(*args, **kwargs)
vars = {}
styles, (style, mapfile, fp) = hgweb_mod.getstyle(
req, config, self.templatepath
)
if style == styles[0]:
vars[b'style'] = style
sessionvars = webutil.sessionvars(vars, b'?')
logourl = config(b'web', b'logourl')
logoimg = config(b'web', b'logoimg')
staticurl = (
config(b'web', b'staticurl')
or req.apppath.rstrip(b'/') + b'/static/'
)
if not staticurl.endswith(b'/'):
staticurl += b'/'
defaults = {
b"encoding": encoding.encoding,
b"url": req.apppath + b'/',
b"logourl": logourl,
b"logoimg": logoimg,
b"staticurl": staticurl,
b"sessionvars": sessionvars,
b"style": style,
b"nonce": nonce,
}
templatekeyword = registrar.templatekeyword(defaults)
@templatekeyword(b'motd', requires=())
def motd(context, mapping):
if self.motd is not None:
yield self.motd
else:
yield config(b'web', b'motd')
return templater.templater.frommapfile(
mapfile, fp=fp, defaults=defaults
)