From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from localhost (localhost [127.0.0.1]) by turing.freelists.org (Avenir Technologies Mail Multiplex) with ESMTP id 31D42269C0 for ; Thu, 2 Aug 2018 11:44:58 -0400 (EDT) Received: from turing.freelists.org ([127.0.0.1]) by localhost (turing.freelists.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id 9zGwaTM6TSCO for ; Thu, 2 Aug 2018 11:44:57 -0400 (EDT) Received: from smtp60.i.mail.ru (smtp60.i.mail.ru [217.69.128.40]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by turing.freelists.org (Avenir Technologies Mail Multiplex) with ESMTPS id 4CAAB23C1C for ; Thu, 2 Aug 2018 11:44:57 -0400 (EDT) From: Georgy Kirichenko Subject: [tarantool-patches] [PATCH] Fix lua socket polling in case of a spurious wakeup Date: Thu, 2 Aug 2018 18:44:53 +0300 Message-Id: <859b06efe0827949f49623ccec7bd4e4738683ac.1533224602.git.georgy@tarantool.org> Sender: tarantool-patches-bounce@freelists.org Errors-to: tarantool-patches-bounce@freelists.org Reply-To: tarantool-patches@freelists.org List-help: List-unsubscribe: List-software: Ecartis version 1.0.0 List-Id: tarantool-patches List-subscribe: List-owner: List-post: List-archive: To: tarantool-patches@freelists.org Cc: Georgy Kirichenko socket_writable/socket_readable handles socket.iowait spurious wakeup until event is happened or timeout is exceeded. Fixes #3344 --- Issue: https://github.com/tarantool/tarantool/issues/3344 Branch: https://github.com/tarantool/tarantool/tree/g.kirichenko/gh-3344-socket-io-spurios-wakeup src/lua/socket.lua | 67 ++++++++++++++++++++------------------ test/app/socket.result | 70 ++++++++++++++++++++++++++++++++++++++++ test/app/socket.test.lua | 29 +++++++++++++++++ 3 files changed, 135 insertions(+), 31 deletions(-) diff --git a/src/lua/socket.lua b/src/lua/socket.lua index 06306eae2..9fcaee0e8 100644 --- a/src/lua/socket.lua +++ b/src/lua/socket.lua @@ -328,12 +328,18 @@ local function do_wait(self, what, timeout) self._errno = nil timeout = timeout or TIMEOUT_INFINITY - local res = internal.iowait(fd, what, timeout) - if res == 0 then - self._errno = boxerrno.ETIMEDOUT - return 0 + local deadline = fiber.clock() + timeout + local events + + while fiber.clock() <= deadline do + events = internal.iowait(fd, what, deadline - fiber.clock()) + fiber.testcancel() + if events ~= 0 and events ~= '' then + return events + end end - return res + self._errno = boxerrno.ETIMEDOUT + return events end local function socket_readable(self, timeout) @@ -662,7 +668,7 @@ local function read(self, limit, timeout, check, ...) return data end - while timeout > 0 do + while timeout >= 0 do local started = fiber.clock() assert(rbuf:size() < limit) @@ -689,15 +695,9 @@ local function read(self, limit, timeout, check, ...) return nil end - if not socket_readable(self, timeout) then - return nil - end - if timeout <= 0 then - break - end + socket_readable(self, timeout) timeout = timeout - ( fiber.clock() - started ) end - self._errno = boxerrno.ETIMEDOUT return nil end @@ -736,7 +736,7 @@ local function socket_write(self, octets, timeout) end local started = fiber.clock() - while true do + while timeout >= 0 do local written = syswrite(self, p, e - p) if written == 0 then return p - s -- eof @@ -750,11 +750,10 @@ local function socket_write(self, octets, timeout) return nil end + socket_writable(self, timeout) timeout = timeout - (fiber.clock() - started) - if timeout <= 0 or not socket_writable(self, timeout) then - break - end end + return p - s end local function socket_send(self, octets, flags) @@ -935,16 +934,19 @@ local function socket_tcp_connect(s, address, port, timeout) -- Wait until the connection is established or ultimately fails. -- In either condition the socket becomes writable. To tell these -- conditions appart SO_ERROR must be consulted (man connect). - if socket_writable(s, timeout) then - s._errno = socket_getsockopt(s, 'SOL_SOCKET', 'SO_ERROR') - else - s._errno = boxerrno.ETIMEDOUT - end - if s._errno ~= 0 then - return nil + local deadline = timeout + fiber.clock() + while deadline - fiber.clock() >= 0 do + if socket_writable(s, deadline - fiber.clock()) then + s._errno = socket_getsockopt(s, 'SOL_SOCKET', 'SO_ERROR') + if s._errno == 0 then + return true + else + return nil + end + end end - -- Connected - return true + s._errno = boxerrno.ETIMEDOUT + return nil end local function tcp_connect(host, port, timeout) @@ -1005,7 +1007,8 @@ end local function tcp_server_loop(server, s, addr) fiber.name(format("%s/%s:%s", server.name, addr.host, addr.port), {truncate = true}) log.info("started") - while socket_readable(s) do + while true do + socket_readable(s) local sc, from = socket_accept(s) if sc == nil then local errno = s._errno @@ -1325,7 +1328,8 @@ end local function lsocket_tcp_accept(self) check_socket(self) local deadline = fiber.clock() + (self.timeout or TIMEOUT_INFINITY) - repeat + while deadline - fiber.clock() >= 0 do + socket_readable(self, deadline - fiber.clock()) local client = socket_accept(self) if client then setmetatable(client, lsocket_tcp_client_mt) @@ -1335,7 +1339,7 @@ local function lsocket_tcp_accept(self) if not errno_is_transient[errno] then break end - until not socket_readable(self, deadline - fiber.clock()) + end return nil, socket_error(self) end @@ -1390,7 +1394,8 @@ local function lsocket_tcp_receive(self, pattern, prefix) elseif pattern == "*a" then local result = { prefix } local deadline = fiber.clock() + (self.timeout or TIMEOUT_INFINITY) - repeat + while deadline - fiber.clock() >= 0 do + socket_readable(self, deadline - fiber.clock()) local data = socket_sysread(self) if data == nil then if not errno_is_transient[self._errno] then @@ -1401,7 +1406,7 @@ local function lsocket_tcp_receive(self, pattern, prefix) else table.insert(result, data) end - until not socket_readable(self, deadline - fiber.clock()) + end if #result == 1 then return nil, 'closed', table.concat(result) end diff --git a/test/app/socket.result b/test/app/socket.result index b4d4a9a78..d6f6762e0 100644 --- a/test/app/socket.result +++ b/test/app/socket.result @@ -2230,6 +2230,76 @@ s:close() --- - 1 ... +--gh-3344 connection should not fail is there is a spurious wakeup for io fiber +test_run:cmd("setopt delimiter ';'") +--- +- true +... +echo_fiber = nil +server = socket.tcp_server('localhost', 0, { handler = function(s) + echo_fiber = fiber.self() + while true do + local b = s:read(1, 0.1) + if b ~= nil then + s:write(b) + end + end +end, name = 'echoserv'}); +--- +... +test_run:cmd("setopt delimiter ''"); +--- +- true +... +addr = server:name() +--- +... +client = socket.tcp_connect(addr.host, addr.port) +--- +... +echo_fiber ~= nil +--- +- true +... +client:write('hello') +--- +- 5 +... +client:read(5, 0.1) == 'hello' +--- +- true +... +-- send spurious wakeup +fiber.wakeup(echo_fiber) +--- +... +fiber.sleep(0) +--- +... +client:write('world') +--- +- 5 +... +client:read(5, 0.1) == 'world' +--- +- true +... +-- cancel fiber +fiber.cancel(echo_fiber) +--- +... +client:write('!') +--- +- 1 +... +client:read(1, 0.1) == '' +--- +- true +... +server:close() +--- +- true +... test_run:cmd("clear filter") --- - true diff --git a/test/app/socket.test.lua b/test/app/socket.test.lua index f6539438b..4e44b7ac0 100644 --- a/test/app/socket.test.lua +++ b/test/app/socket.test.lua @@ -736,4 +736,33 @@ sc:connect(host, port) sc:close() s:close() +--gh-3344 connection should not fail is there is a spurious wakeup for io fiber +test_run:cmd("setopt delimiter ';'") +echo_fiber = nil +server = socket.tcp_server('localhost', 0, { handler = function(s) + echo_fiber = fiber.self() + while true do + local b = s:read(1, 0.1) + if b ~= nil then + s:write(b) + end + end +end, name = 'echoserv'}); +test_run:cmd("setopt delimiter ''"); +addr = server:name() +client = socket.tcp_connect(addr.host, addr.port) +echo_fiber ~= nil +client:write('hello') +client:read(5, 0.1) == 'hello' +-- send spurious wakeup +fiber.wakeup(echo_fiber) +fiber.sleep(0) +client:write('world') +client:read(5, 0.1) == 'world' +-- cancel fiber +fiber.cancel(echo_fiber) +client:write('!') +client:read(1, 0.1) == '' +server:close() + test_run:cmd("clear filter") -- 2.18.0