Re: [PATCH 3/7] passt: Integrate main event loop with threading infrastructure

On Fri, Jul 31, 2026 at 06:46:24PM +0200, Laurent Vivier wrote:

Convert the main event loop to use the threading subsystem. The main process now registers passt_worker() as thread #0 and starts it through the threading infrastructure instead of running a manual epoll_wait loop.

Signed-off-by: Laurent Vivier --- passt.c | 20 ++++---------------- threading.c | 3 --- 2 files changed, 4 insertions(+), 19 deletions(-)

diff --git a/passt.c b/passt.c index 8a06838c5ed8..2cedb7ba0756 100644 --- a/passt.c +++ b/passt.c @@ -333,8 +333,7 @@ static void passt_worker(void *opaque, int nfds, struct epoll_event *events) */ int main(int argc, char **argv) { - struct epoll_event events[NUM_EPOLL_EVENTS]; - int nfds, devnull_fd = -1, fd; + int devnull_fd = -1, fd; struct ctx *c = &passt_ctx; struct rlimit limit; struct timespec now; @@ -377,9 +376,7 @@ int main(int argc, char **argv) madvise(pkt_buf, sizeof(pkt_buf), MADV_HUGEPAGE);

threading_init(); - c->epollfd = epoll_create1(EPOLL_CLOEXEC); - if (c->epollfd == -1) - die_perror("Failed to create epoll file descriptor"); + c->epollfd = threading_epollfd(THREADING_ID_DEFAULT);

if (getrlimit(RLIMIT_NOFILE, &limit)) die_perror("Failed to get maximum value of open files limit"); @@ -449,15 +446,6 @@ int main(int argc, char **argv)

isolate_postfork(c);

-loop: - /* NOLINTBEGIN(bugprone-branch-clone): intervals can be the same */ - /* cppcheck-suppress [duplicateValueTernary, unmatchedSuppression] */ - nfds = epoll_wait(c->epollfd, events, NUM_EPOLL_EVENTS, TIMER_INTERVAL); - /* NOLINTEND(bugprone-branch-clone) */ - if (nfds == -1 && errno != EINTR) - die_perror("epoll_wait() failed in main loop"); - - passt_worker(c, nfds, events); - - goto loop; + threading_worker_set(THREADING_ID_DEFAULT, passt_worker, c); + threading_start_thread(THREADING_ID_DEFAULT);

Invoking this through threading_start_thread(), which then special cases thread 0 seems a bit odd. Could you just directly call threading_worker()?

} diff --git a/threading.c b/threading.c index fd5b30ed7ff6..e1ed644f5864 100644 --- a/threading.c +++ b/threading.c @@ -66,7 +66,6 @@ void threading_init(void) * * Return: 0 on success, -1 if thread index is invalid */ -/* cppcheck-suppress unusedFunction */ int threading_worker_set(unsigned int threadid, void (*worker)(void *, int, struct epoll_event *), void *opaque) @@ -90,7 +89,6 @@ int threading_worker_set(unsigned int threadid, * * Return: epoll file descriptor for the specified thread, -1 if index invalid */ -/* cppcheck-suppress unusedFunction */ int threading_epollfd(unsigned int threadid) { if (threadid >= ARRAY_SIZE(threads)) @@ -135,7 +133,6 @@ static void *threading_worker(void *opaque) * * #syscalls rt_sigaction rt_sigprocmask mprotect getrandom brk clone3 rseq set_robust_list clock_nanosleep */ -/* cppcheck-suppress unusedFunction */ void threading_start_thread(unsigned int threadid) { struct threading_context *tc; -- 2.54.0

-- David Gibson (he or they) | I'll have my music baroque, and my code david AT gibson.dropbear.id.au | minimalist, thank you, not the other way | around. http://www.ozlabs.org/~dgibson