Hi, > -----Original Message----- > From: Stephen Hemminger <step...@networkplumber.org> > Sent: Monday, January 13, 2025 10:10 PM > To: Gagandeep Singh <g.si...@nxp.com> > Cc: dev@dpdk.org > Subject: Re: [PATCH] eal: add worker threads cleanup in rte_eal_cleanup() > > On Mon, 13 Jan 2025 05:13:01 +0000 > Gagandeep Singh <g.si...@nxp.com> wrote: > > > Hi, > > > > > -----Original Message----- > > > From: Stephen Hemminger <step...@networkplumber.org> > > > Sent: Friday, January 10, 2025 10:49 PM > > > To: Gagandeep Singh <g.si...@nxp.com> > > > Cc: dev@dpdk.org > > > Subject: Re: [PATCH] eal: add worker threads cleanup in > > > rte_eal_cleanup() > > > > > > On Fri, 10 Jan 2025 12:17:17 +0530 > > > Gagandeep Singh <g.si...@nxp.com> wrote: > > > > > > > This patch introduces a worker thread cleanup function in the EAL > > > > library, ensuring proper termination of created pthreads and > > > > invocation of registered pthread destructors. > > > > This guarantees the correct cleanup of thread-specific resources, > > > > used by drivers or applications. > > > > > > > > Signed-off-by: Gagandeep Singh <g.si...@nxp.com> > > > > --- > > > > > > What problem is this trying to solve? > > > > > > Canceling threads sends signals and can be problematic. > > > Many of the operations done in drivers are not signal safe. > > > > To ensure the proper cleanup of thread-specific resources, the DPAA driver > initializes pthread-specific destructors using pthread_key_create(). These > destructors are executed only when a thread terminates or the key is deleted. > However, since threads are not terminated when the application is killed, > these > destructors are not executed, resulting in resource leaks. > > To address this issue, we propose adding thread termination code to > > rte_eal_cleanup() to ensure that threads are properly terminated, > > thereby triggering the execution of pthread-specific destructors > > > > Any alternate suggestion in case pthread_cancel is not a better > > solution? We can add pthread join timeout to avoid blocking on thread stuck > > or > May be any way to call pthread_exit? > > The DPAA driver is the problem here. It should not be using pthread_key. > Other drivers don't do this. Other drivers do setup on probe and cleanup on > close. > > An application doing a clean shutdown should do what existing testpmd, l3fwd, > do > - wait for worker threads to go idle > - stop all ports > - close all ports > - call eal cleanup > > If DPAA driver needs pthread_key it should handling that in the close. > But it really should be using DPDK thread local storage for this. > This is fine for graceful application termination, but what about non-graceful application termination? I have a DPAA bus cleanup patch ready, and will submit it soon, But we still need destructor in case application exit without calling the rte_eal_cleanup().
I can see DPDK is giving an API rte_thread_key_create() which is defined only in UNIX and windows. Why not for Linux? I know DPAA driver is using pthread_key which it should not use but instead use rte_thread_key_create() provided by DPDK which we can replace. Having pthread destructor is still a valid case in my opinion.
