On Thu, Jun 09, 2016 at 01:34:31PM +0300, Vladimir Davydov wrote: > On Mon, Jun 06, 2016 at 07:26:57PM +0300, Cyrill Gorcunov wrote: > > After tty code redesing we've been requiring container to start > > first before be able to connect into it via vzctl console command. > > Here we rather allow userspace tool to wait until container brought > > to life and proceed connecting into console. > > > > https://jira.sw.ru/browse/PSBM-39463 > > > > Signed-off-by: Cyrill Gorcunov <gorcu...@virtuozzo.com> > > CC: Vladimir Davydov <vdavy...@virtuozzo.com> > > CC: Konstantin Khorenko <khore...@virtuozzo.com> > > CC: Igor Sukhih <i...@virtuozzo.com> > > CC: Pavel Emelyanov <xe...@virtuozzo.com> > > --- > > include/linux/ve.h | 2 ++ > > kernel/ve/ve.c | 48 ++++++++++++++++++++++++++++++++++++++++++++++++ > > kernel/ve/vecalls.c | 23 +++++++++++++++++++++-- > > 3 files changed, 71 insertions(+), 2 deletions(-) > > > > Index: linux-pcs7.git/include/linux/ve.h > > =================================================================== > > --- linux-pcs7.git.orig/include/linux/ve.h > > +++ linux-pcs7.git/include/linux/ve.h > > @@ -215,6 +215,8 @@ void ve_stop_ns(struct pid_namespace *ns > > void ve_exit_ns(struct pid_namespace *ns); > > int ve_start_container(struct ve_struct *ve); > > > > +int ve_console_wait(envid_t veid); > > + > > extern bool current_user_ns_initial(void); > > struct user_namespace *ve_init_user_ns(void); > > > > Index: linux-pcs7.git/kernel/ve/ve.c > > =================================================================== > > --- linux-pcs7.git.orig/kernel/ve/ve.c > > +++ linux-pcs7.git/kernel/ve/ve.c > > @@ -260,6 +260,49 @@ struct user_namespace *ve_init_user_ns(v > > } > > EXPORT_SYMBOL(ve_init_user_ns); > > > > +static DEFINE_IDR(ve_idr_console); > > +static DECLARE_RWSEM(ve_console_sem); > > + > > +int ve_console_wait(envid_t veid) > > +{ > > + DECLARE_COMPLETION_ONSTACK(console_work); > > + int ret; > > + > > + down_write(&ve_console_sem); > > + if (idr_find(&ve_idr_console, veid)) { > > + up_write(&ve_console_sem); > > + return -EEXIST; > > + } > > + > > + ret = idr_alloc(&ve_idr_console, &console_work, veid, veid + 1, > > GFP_KERNEL); > > + if (ret < 0) { > > + if (ret == -ENOSPC) > > + ret = -EEXIST; > > + } else > > + ret = 0; > > + downgrade_write(&ve_console_sem); > > + > > + if (!ret) { > > + ret = wait_for_completion_interruptible(&console_work); > > + idr_remove(&ve_idr_console, veid); > > + } > > + > > + up_read(&ve_console_sem); > > + return ret; > > +} > > +EXPORT_SYMBOL(ve_console_wait); > > + > > +static void ve_console_notify(struct ve_struct *ve) > > +{ > > + struct completion *console_work; > > + > > + down_read(&ve_console_sem); > > + console_work = idr_find(&ve_idr_console, ve->veid); > > + if (console_work) > > + complete(console_work); > > + up_read(&ve_console_sem); > > +} > > + > > int nr_threads_ve(struct ve_struct *ve) > > { > > return cgroup_task_count(ve->css.cgroup); > > @@ -494,6 +537,11 @@ int ve_start_container(struct ve_struct > > > > get_ve(ve); /* for ve_exit_ns() */ > > > > + /* > > + * Console waiter are to be notified at the very > > + * end when everything else is ready. > > + */ > > + ve_console_notify(ve); > > return 0; > > > > err_iterate: > > Index: linux-pcs7.git/kernel/ve/vecalls.c > > =================================================================== > > --- linux-pcs7.git.orig/kernel/ve/vecalls.c > > +++ linux-pcs7.git/kernel/ve/vecalls.c > > @@ -991,8 +991,27 @@ static int ve_configure(envid_t veid, un > > int err = -ENOKEY; > > > > ve = get_ve_by_id(veid); > > - if (!ve) > > - return -EINVAL; > > + if (!ve) { > > + > > + if (key != VE_CONFIGURE_OPEN_TTY) > > + return -EINVAL; > > + /* > > + * Offline console management: > > + * wait until ve is up and proceed. > > + */ > > What if a VE is created right here, before we call ve_console_wait()? > Looks like the caller will hang forever...
Yeah, could be a race. Thanks! > > + err = ve_console_wait(veid); > > + if (err) > > + return err; > > + > > + /* > > + * A container should not exit immediately once > > + * started but if it does, for any reason, simply > > + * exit out gracefully. > > + */ > > + ve = get_ve_by_id(veid); > > + if (!ve) > > + return -ENOENT; > > + } > > Can't we fold this into vtty_open_master()? The latter doesn't need ve > object, it only needs veid, which is known here. Will do. _______________________________________________ Devel mailing list Devel@openvz.org https://lists.openvz.org/mailman/listinfo/devel
