On Fri, Jul 31, 2026 at 06:46:26PM +0200, Laurent Vivier wrote:
> The main epoll file descriptor is now managed by the threading subsystem,
> so there's no need to store it in the context structure.
> All code that previously accessed c->epollfd now calls
> threading_epollfd(THREADING_ID_DEFAULT) to get the main event loop's
> epoll file descriptor.
> 
> Signed-off-by: Laurent Vivier <lvivier@redhat.com>

Reviewed-by: David Gibson <david@gibson.dropbear.id.au>

> ---
>  conf.c       | 10 +++++++---
>  fwd.c        |  4 +++-
>  netlink.c    |  4 +++-
>  passt.c      |  1 -
>  passt.h      |  2 --
>  pasta.c      |  3 ++-
>  pif.c        |  3 ++-
>  repair.c     | 12 ++++++++----
>  tap.c        |  9 ++++++---
>  tcp_splice.c |  1 +
>  vhost_user.c |  9 +++++----
>  11 files changed, 37 insertions(+), 21 deletions(-)
> 
> diff --git a/conf.c b/conf.c
> index faf268140321..733bad4228cb 100644
> --- a/conf.c
> +++ b/conf.c
> @@ -53,6 +53,7 @@
>  #include "pesto.h"
>  #include "serialise.h"
>  #include "parse.h"
> +#include "threading.h"
>  
>  #define NETNS_RUN_DIR	"/run/netns"
>  
> @@ -1164,7 +1165,8 @@ static void conf_sock_listen(const struct ctx *c)
>  		die_perror("Couldn't listen on configuration socket");
>  
>  	ref.fd = c->fd_control_listen;
> -	if (epoll_add(c->epollfd, EPOLLIN | EPOLLET, ref))
> +	if (epoll_add(threading_epollfd(THREADING_ID_DEFAULT),
> +		      EPOLLIN | EPOLLET, ref))
>  		die_perror("Couldn't add configuration socket to epoll");
>  }
>  
> @@ -2117,7 +2119,8 @@ static int conf_recv_rules(const struct ctx *c, int fd)
>  static void conf_close(struct ctx *c)
>  {
>  	debug("Closing configuration socket");
> -	epoll_ctl(c->epollfd, EPOLL_CTL_DEL, c->fd_control, NULL);
> +	epoll_ctl(threading_epollfd(THREADING_ID_DEFAULT), EPOLL_CTL_DEL,
> +		  c->fd_control, NULL);
>  	close(c->fd_control);
>  	c->fd_control = -1;
>  }
> @@ -2180,7 +2183,8 @@ retry:
>  		warn_perror("Can't get configuration client credentials");
>  
>  	c->fd_control = ref.fd = fd;
> -	rc = epoll_add(c->epollfd, EPOLLIN | EPOLLET, ref);
> +	rc = epoll_add(threading_epollfd(THREADING_ID_DEFAULT),
> +		       EPOLLIN | EPOLLET, ref);
>  	if (rc < 0) {
>  		warn_perror("epoll_ctl() on configuration socket");
>  		goto fail;
> diff --git a/fwd.c b/fwd.c
> index 5679a3d606ea..fa6679ea1b2e 100644
> --- a/fwd.c
> +++ b/fwd.c
> @@ -33,6 +33,7 @@
>  #include "netlink.h"
>  #include "arp.h"
>  #include "ndp.h"
> +#include "threading.h"
>  
>  #define NEIGH_TABLE_SLOTS    1024
>  #define NEIGH_TABLE_SIZE     (NEIGH_TABLE_SLOTS / 2)
> @@ -377,7 +378,8 @@ static int fwd_sync_one(const struct ctx *c, uint8_t pif, unsigned idx,
>  			/* We don't want to listen on this port */
>  			if (fd >= 0) {
>  				/* We already are, so stop */
> -				epoll_del(c->epollfd, fd);
> +				epoll_del(threading_epollfd(THREADING_ID_DEFAULT),
> +					  fd);
>  				close(fd);
>  				socks[port - rule->first] = -1;
>  			}
> diff --git a/netlink.c b/netlink.c
> index 8d20dbb57fb8..8fffe490b6f3 100644
> --- a/netlink.c
> +++ b/netlink.c
> @@ -37,6 +37,7 @@
>  #include "ip.h"
>  #include "netlink.h"
>  #include "epoll_ctl.h"
> +#include "threading.h"
>  
>  /* Same as RTA_NEXT() but for nexthops: RTNH_NEXT() doesn't take 'attrlen' */
>  #define RTNH_NEXT_AND_DEC(rtnh, attrlen)				\
> @@ -1292,7 +1293,8 @@ int nl_neigh_notify_init(const struct ctx *c)
>  	}
>  
>  	ev.data.u64 = ref.u64;
> -	if (epoll_ctl(c->epollfd, EPOLL_CTL_ADD, nl_sock_neigh, &ev) == -1) {
> +	if (epoll_ctl(threading_epollfd(THREADING_ID_DEFAULT), EPOLL_CTL_ADD,
> +		      nl_sock_neigh, &ev) == -1) {
>  		warn_perror("epoll_ctl() on neighbour notifier socket failed");
>  		close(nl_sock_neigh);
>  		nl_sock_neigh = -1;
> diff --git a/passt.c b/passt.c
> index 57290a5a7c6e..469e2525f545 100644
> --- a/passt.c
> +++ b/passt.c
> @@ -376,7 +376,6 @@ int main(int argc, char **argv)
>  	madvise(pkt_buf, sizeof(pkt_buf), MADV_HUGEPAGE);
>  
>  	threading_init();
> -	c->epollfd = threading_epollfd(THREADING_ID_DEFAULT);
>  
>  	if (getrlimit(RLIMIT_NOFILE, &limit))
>  		die_perror("Failed to get maximum value of open files limit");
> diff --git a/passt.h b/passt.h
> index 00ef5a8f85e5..40abc5995ffd 100644
> --- a/passt.h
> +++ b/passt.h
> @@ -190,7 +190,6 @@ struct ip6_ctx {
>   * @no_netns_quit:	In pasta mode, don't exit if fs-bound namespace is gone
>   * @netns_base:		Base name for fs-bound namespace, if any, in pasta mode
>   * @netns_dir:		Directory of fs-bound namespace, if any, in pasta mode
> - * @epollfd:		File descriptor for epoll instance
>   * @fd_tap_listen:	File descriptor for listening AF_UNIX socket, if any
>   * @fd_tap:		AF_UNIX socket, tuntap device, or pre-opened socket
>   * @fd_control_listen:	Listening control/configuration socket, if any
> @@ -266,7 +265,6 @@ struct ctx {
>  	char netns_base[PATH_MAX];
>  	char netns_dir[PATH_MAX];
>  
> -	int epollfd;
>  	int fd_tap_listen;
>  	int fd_tap;
>  	int fd_control_listen;
> diff --git a/pasta.c b/pasta.c
> index 5aa56b78d262..0a742a4f9abe 100644
> --- a/pasta.c
> +++ b/pasta.c
> @@ -50,6 +50,7 @@
>  #include "netlink.h"
>  #include "log.h"
>  #include "epoll_ctl.h"
> +#include "threading.h"
>  
>  #define HOSTNAME_PREFIX		"pasta-"
>  
> @@ -517,7 +518,7 @@ void pasta_netns_quit_init(const struct ctx *c)
>  
>  	ref.fd = fd;
>  
> -	epoll_add(c->epollfd, EPOLLIN, ref);
> +	epoll_add(threading_epollfd(THREADING_ID_DEFAULT), EPOLLIN, ref);
>  }
>  
>  /**
> diff --git a/pif.c b/pif.c
> index 8ade587c623a..e0a36413878b 100644
> --- a/pif.c
> +++ b/pif.c
> @@ -16,6 +16,7 @@
>  #include "ip.h"
>  #include "inany.h"
>  #include "epoll_ctl.h"
> +#include "threading.h"
>  
>  const char pif_type_str[][PIF_NAME_SIZE] = {
>  	[PIF_NONE]		= "<none>",
> @@ -130,7 +131,7 @@ int pif_listen(const struct ctx *c, uint8_t proto, uint8_t pif,
>  		goto fail;
>  	}
>  
> -	ret = epoll_add(c->epollfd, EPOLLIN, ref);
> +	ret = epoll_add(threading_epollfd(THREADING_ID_DEFAULT), EPOLLIN, ref);
>  	if (ret < 0)
>  		goto fail;
>  
> diff --git a/repair.c b/repair.c
> index f31ccceed7c6..7560242cf1c1 100644
> --- a/repair.c
> +++ b/repair.c
> @@ -23,6 +23,7 @@
>  #include "flow.h"
>  #include "flow_table.h"
>  #include "epoll_ctl.h"
> +#include "threading.h"
>  
>  #include "repair.h"
>  
> @@ -58,8 +59,9 @@ void repair_sock_init(const struct ctx *c)
>  	}
>  
>  	ref.fd = c->fd_repair_listen;
> -	if (epoll_add(c->epollfd, EPOLLIN | EPOLLHUP | EPOLLET, ref))
> -		err("repair helper socket epoll_ctl(), won't migrate");
> +	if (epoll_add(threading_epollfd(THREADING_ID_DEFAULT),
> +		      EPOLLIN | EPOLLHUP | EPOLLET, ref))
> +		err_perror("repair helper socket epoll_ctl(), won't migrate");
>  }
>  
>  /**
> @@ -115,7 +117,8 @@ int repair_listen_handler(struct ctx *c, uint32_t events)
>  
>  	ref.fd = c->fd_repair;
>  
> -	rc = epoll_add(c->epollfd, EPOLLHUP | EPOLLET, ref);
> +	rc = epoll_add(threading_epollfd(THREADING_ID_DEFAULT),
> +		       EPOLLHUP | EPOLLET, ref);
>  	if (rc < 0) {
>  		debug("epoll_ctl() on TCP_REPAIR helper socket");
>  		close(c->fd_repair);
> @@ -134,7 +137,8 @@ void repair_close(struct ctx *c)
>  {
>  	debug("Closing TCP_REPAIR helper socket");
>  
> -	epoll_ctl(c->epollfd, EPOLL_CTL_DEL, c->fd_repair, NULL);
> +	epoll_ctl(threading_epollfd(THREADING_ID_DEFAULT), EPOLL_CTL_DEL,
> +		  c->fd_repair, NULL);
>  	close(c->fd_repair);
>  	c->fd_repair = -1;
>  }
> diff --git a/tap.c b/tap.c
> index 25cde67538ac..d9be6bcc41a0 100644
> --- a/tap.c
> +++ b/tap.c
> @@ -61,6 +61,7 @@
>  #include "vhost_user.h"
>  #include "vu_common.h"
>  #include "epoll_ctl.h"
> +#include "threading.h"
>  
>  /* Maximum allowed frame lengths (including L2 header) */
>  
> @@ -1226,7 +1227,7 @@ void tap_sock_reset(struct ctx *c)
>  		passt_exit(EXIT_SUCCESS);
>  
>  	/* Close the connected socket, wait for a new connection */
> -	epoll_del(c->epollfd, c->fd_tap);
> +	epoll_del(threading_epollfd(THREADING_ID_DEFAULT), c->fd_tap);
>  	close(c->fd_tap);
>  	c->fd_tap = -1;
>  	if (c->mode == MODE_VU)
> @@ -1417,7 +1418,8 @@ static void tap_sock_unix_init(const struct ctx *c)
>  
>  	ref.fd = c->fd_tap_listen;
>  
> -	epoll_add(c->epollfd, EPOLLIN | EPOLLET, ref);
> +	epoll_add(threading_epollfd(THREADING_ID_DEFAULT), EPOLLIN | EPOLLET,
> +		  ref);
>  }
>  
>  /**
> @@ -1465,7 +1467,8 @@ static void tap_start_connection(const struct ctx *c)
>  		break;
>  	}
>  
> -	epoll_add(c->epollfd, EPOLLIN | EPOLLRDHUP, ref);
> +	epoll_add(threading_epollfd(THREADING_ID_DEFAULT),
> +		  EPOLLIN | EPOLLRDHUP, ref);
>  
>  	if (!tap_is_ready(c))
>  		return;
> diff --git a/tcp_splice.c b/tcp_splice.c
> index 8617e62cea9a..fc5b6c25670d 100644
> --- a/tcp_splice.c
> +++ b/tcp_splice.c
> @@ -56,6 +56,7 @@
>  #include "inany.h"
>  #include "flow.h"
>  #include "epoll_ctl.h"
> +#include "threading.h"
>  
>  #include "flow_table.h"
>  
> diff --git a/vhost_user.c b/vhost_user.c
> index 8ba3949e4e9d..ad316aee12c3 100644
> --- a/vhost_user.c
> +++ b/vhost_user.c
> @@ -44,6 +44,7 @@
>  #include "pcap.h"
>  #include "migrate.h"
>  #include "epoll_ctl.h"
> +#include "threading.h"
>  
>  /* vhost-user version we are compatible with */
>  #define VHOST_USER_VERSION 1
> @@ -736,7 +737,7 @@ static bool vu_get_vring_base_exec(struct vu_dev *vdev,
>  		vdev->vq[idx].call_fd = -1;
>  	}
>  	if (vdev->vq[idx].kick_fd != -1) {
> -		epoll_del(vdev->context->epollfd, vdev->vq[idx].kick_fd);
> +		epoll_del(threading_epollfd(THREADING_ID_DEFAULT), vdev->vq[idx].kick_fd);
>  		close(vdev->vq[idx].kick_fd);
>  		vdev->vq[idx].kick_fd = -1;
>  	}
> @@ -757,7 +758,7 @@ static void vu_set_watch(const struct vu_dev *vdev, int idx)
>  		.queue = idx
>  	 };
>  
> -	epoll_add(vdev->context->epollfd, EPOLLIN, ref);
> +	epoll_add(threading_epollfd(THREADING_ID_DEFAULT), EPOLLIN, ref);
>  }
>  
>  /**
> @@ -802,7 +803,7 @@ static bool vu_set_vring_kick_exec(struct vu_dev *vdev,
>  	vu_check_queue_msg_file(vmsg);
>  
>  	if (vdev->vq[idx].kick_fd != -1) {
> -		epoll_del(vdev->context->epollfd, vdev->vq[idx].kick_fd);
> +		epoll_del(threading_epollfd(THREADING_ID_DEFAULT), vdev->vq[idx].kick_fd);
>  		close(vdev->vq[idx].kick_fd);
>  		vdev->vq[idx].kick_fd = -1;
>  	}
> @@ -1095,7 +1096,7 @@ void vu_cleanup(struct vu_dev *vdev)
>  			vq->err_fd = -1;
>  		}
>  		if (vq->kick_fd != -1) {
> -			epoll_del(vdev->context->epollfd, vq->kick_fd);
> +			epoll_del(threading_epollfd(THREADING_ID_DEFAULT), vq->kick_fd);
>  			close(vq->kick_fd);
>  			vq->kick_fd = -1;
>  		}
> -- 
> 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