revlog: remove unnecessary cache validation in _chunks
Previously, we likely called _chunkraw() multiple times in order to
ensure it didn't change out from under us. I'm pretty certain this code
had its origins in the days where we attempted to have thread safety of
localrepository and thus revlog instances.
revlog instances are already not thread safe for writing. And, as of
Mercurial 3.6, hgweb uses a separate localrepository instance per
request, so there should only be a single thread reading a revlog at
a time. We more or less decided that attempting to make classes like
revlog thread safe is a lost cause.
So, this patch removes thread safety from _chunks. As a result, we make
one less call into _chunkraw() when the initial read isn't serviced
by the cache. This translates to savings of 4 function calls overall
and possibly prevents the creation of an additional buffer view into the
cache. I doubt this translates into any real world performance wins
because decompression will almost certainly dwarf time spent in
_chunks(). But it does make the code simpler, so it is an improvement.
#!/usr/bin/env python
#
# checkseclevel - checking section title levels in each online help document
import sys, os
import optparse
# import from the live mercurial repo
os.environ['HGMODULEPOLICY'] = 'py'
sys.path.insert(0, "..")
from mercurial import demandimport; demandimport.enable()
from mercurial.commands import table
from mercurial.help import helptable
from mercurial import extensions
from mercurial import minirst
from mercurial import ui as uimod
level2mark = ['"', '=', '-', '.', '#']
reservedmarks = ['"']
mark2level = {}
for m, l in zip(level2mark, xrange(len(level2mark))):
if m not in reservedmarks:
mark2level[m] = l
initlevel_topic = 0
initlevel_cmd = 1
initlevel_ext = 1
initlevel_ext_cmd = 3
def showavailables(ui, initlevel):
ui.warn((' available marks and order of them in this help: %s\n') %
(', '.join(['%r' % (m * 4) for m in level2mark[initlevel + 1:]])))
def checkseclevel(ui, doc, name, initlevel):
ui.note(('checking "%s"\n') % name)
blocks, pruned = minirst.parse(doc, 0, ['verbose'])
errorcnt = 0
curlevel = initlevel
for block in blocks:
if block['type'] != 'section':
continue
mark = block['underline']
title = block['lines'][0]
if (mark not in mark2level) or (mark2level[mark] <= initlevel):
ui.warn(('invalid section mark %r for "%s" of %s\n') %
(mark * 4, title, name))
showavailables(ui, initlevel)
errorcnt += 1
continue
nextlevel = mark2level[mark]
if curlevel < nextlevel and curlevel + 1 != nextlevel:
ui.warn(('gap of section level at "%s" of %s\n') %
(title, name))
showavailables(ui, initlevel)
errorcnt += 1
continue
ui.note(('appropriate section level for "%s %s"\n') %
(mark * (nextlevel * 2), title))
curlevel = nextlevel
return errorcnt
def checkcmdtable(ui, cmdtable, namefmt, initlevel):
errorcnt = 0
for k, entry in cmdtable.items():
name = k.split("|")[0].lstrip("^")
if not entry[0].__doc__:
ui.note(('skip checking %s: no help document\n') %
(namefmt % name))
continue
errorcnt += checkseclevel(ui, entry[0].__doc__,
namefmt % name,
initlevel)
return errorcnt
def checkhghelps(ui):
errorcnt = 0
for names, sec, doc in helptable:
if callable(doc):
doc = doc(ui)
errorcnt += checkseclevel(ui, doc,
'%s help topic' % names[0],
initlevel_topic)
errorcnt += checkcmdtable(ui, table, '%s command', initlevel_cmd)
for name in sorted(extensions.enabled().keys() +
extensions.disabled().keys()):
mod = extensions.load(ui, name, None)
if not mod.__doc__:
ui.note(('skip checking %s extension: no help document\n') % name)
continue
errorcnt += checkseclevel(ui, mod.__doc__,
'%s extension' % name,
initlevel_ext)
cmdtable = getattr(mod, 'cmdtable', None)
if cmdtable:
errorcnt += checkcmdtable(ui, cmdtable,
'%s command of ' + name + ' extension',
initlevel_ext_cmd)
return errorcnt
def checkfile(ui, filename, initlevel):
if filename == '-':
filename = 'stdin'
doc = sys.stdin.read()
else:
fp = open(filename)
try:
doc = fp.read()
finally:
fp.close()
ui.note(('checking input from %s with initlevel %d\n') %
(filename, initlevel))
return checkseclevel(ui, doc, 'input from %s' % filename, initlevel)
def main():
optparser = optparse.OptionParser("""%prog [options]
This checks all help documents of Mercurial (topics, commands,
extensions and commands of them), if no file is specified by --file
option.
""")
optparser.add_option("-v", "--verbose",
help="enable additional output",
action="store_true")
optparser.add_option("-d", "--debug",
help="debug mode",
action="store_true")
optparser.add_option("-f", "--file",
help="filename to read in (or '-' for stdin)",
action="store", default="")
optparser.add_option("-t", "--topic",
help="parse file as help topic",
action="store_const", dest="initlevel", const=0)
optparser.add_option("-c", "--command",
help="parse file as help of core command",
action="store_const", dest="initlevel", const=1)
optparser.add_option("-e", "--extension",
help="parse file as help of extension",
action="store_const", dest="initlevel", const=1)
optparser.add_option("-C", "--extension-command",
help="parse file as help of extension command",
action="store_const", dest="initlevel", const=3)
optparser.add_option("-l", "--initlevel",
help="set initial section level manually",
action="store", type="int", default=0)
(options, args) = optparser.parse_args()
ui = uimod.ui()
ui.setconfig('ui', 'verbose', options.verbose, '--verbose')
ui.setconfig('ui', 'debug', options.debug, '--debug')
if options.file:
if checkfile(ui, options.file, options.initlevel):
sys.exit(1)
else:
if checkhghelps(ui):
sys.exit(1)
if __name__ == "__main__":
main()