Re: [PATCH] bug: some event from parent might be triggered by children

Le 16 décembre 2009 16:54, Antony Dovgal <tony@daylessday.org> a écrit : > On 16.12.2009 18:33, Jérôme Loyet wrote: >> hi tony, >> >> this patch correct a behaviour that could happened randomly, depending >> on the event lib used (epoll, poll, kqueue, ...). There is some case >> in which an event created by the parent process can be triggered in a >> child. > > Some case? I had this bug several time doing differents stuff. So I don't have a real case to explain here (I can search). > Could you elaborate? It's related to the missing event_init after forking a child. In fpm_children_make(), we have: fork() event_init() /* to reinit libevent, necessary for epoll */ if (in_event_loop) event_loop_break(); I think the bug appears when event_init has been added recently. As event_init reinitiated the libevent environment, the event_loop_break() call has no more effect as it refers to a new environment. So the main loop is still running and event can be triggered by both parent and children. The solution is to move the event_init just after the call. Moreover, I think the previous patch (which add verification on fpm_globals.child) should be included also as it secure the application, just in case :) ++ Jerome Index: sapi/fpm/fpm/fpm_children.c =================================================================== --- sapi/fpm/fpm/fpm_children.c (révision 292214) +++ sapi/fpm/fpm/fpm_children.c (copie de travail) @@ -373,12 +373,12 @@ switch (pid) { case 0 : - event_init(); /* reopen epoll descriptor */ fpm_child_resources_use(child); fpm_globals.is_child = 1; if (in_event_loop) { fpm_event_exit_loop(); } + event_init(); /* refresh libevent environment */ fpm_child_init(wp); return 0; > > The patch certainly does no harm, but maybe it's worth investigating why parent events are > triggered in child processes? > > -- > Wbr, > Antony Dovgal > --- > http://pinba.org - realtime statistics for PHP >