18/06/2026 18:09, Stephen Hemminger: > On Thu, 7 May 2026 13:58:35 -0700 > Stephen Hemminger <[email protected]> wrote: > > > Bugzilla 1942: when a primary process exits cleanly, secondary > > processes other than testpmd do not get notified. The notification > > mechanism added in 25.11 was placed in testpmd and used > > rte_mp_request_sync() with a testpmd-specific action name, so any > > non-testpmd secondary (dpdk-dumpcap, dpdk-pdump, dpdk-procinfo, or > > out-of-tree consumers) would log "Cannot find action: mp_testpmd" > > and the primary would block on the 5 second request timeout. > > > > Putting application-specific IPC actions on a broadcast request path > > is the wrong layer. Notification of primary exit is something every > > secondary needs and should come from EAL, not from each application. > > > > Patch 1 reverts the testpmd-side mechanism (commit f96273c8e9d3). > > The secondary-side primary alive monitor (enable_primary_monitor) > > is preserved and continues to handle detection of primary exit via > > the existing alarm-based polling of rte_eal_primary_proc_alive(). > > > > Patch 2 adds a generic EAL-level notification. On primary cleanup, > > rte_mp_channel_cleanup() broadcasts an MP_REQ_QUIT message to all > > known secondaries via rte_mp_sendmsg(). Secondaries register an > > internal action handler that tears down their own MP channel on > > receipt. No new public API; no application changes required for > > any secondary, in-tree or out. > > > > This is the minimum fix suitable for backport to 25.11 stable. > > It addresses the clean exit case. The crash case (primary killed > > or signaled) continues to be handled by the existing > > rte_eal_primary_proc_alive() polling on the secondary side, which > > detects the primary's release of the config file lock. > > > > A more complete solution using a connected socket type (SOCK_SEQPACKET) > > is planned since that can handle both planned and forced exiting > > of the primary. > > > > Tested with testpmd (primary) and dpdk-dumpcap, dpdk-pdump, > > dpdk-procinfo (secondaries). > > > > > > Stephen Hemminger (2): > > Revert "app/testpmd: stop forwarding in secondary process" > > eal: notify secondary on primary exit > > > > app/test-pmd/testpmd.c | 103 ++----------------------------- > > lib/eal/common/eal_common_proc.c | 51 ++++++++++++++- > > 2 files changed, 53 insertions(+), 101 deletions(-) > > > > This is a real bug fix. Even if AI is being overly wordy in describing > it; what it does is move the notification from being testpmd -> testpmd only > to a more general primary -> secondary mechanism. > > Without it can demonstrate the bug rather trivially with packet > capture tools (pdump or dumpcap) > > Could this get reviewed?
Anatoly reviewed. Applied, thanks.
