diff options
| author |   wanghanlin <wanghanlin@corp.netease.com> | 2021-03-18 20:00:41 +0800 |
|---|---|---|
| committer |   Florin Coras <florin.coras@gmail.com> | 2021-03-22 14:23:06 +0000 |
| commit | 8919fec5acb14d176b992b71108f9a912d98161e (patch) | |
| tree | b99473dbba9e6d91c1cc6285ec35c256373aa749 | |
| parent | 156158f06d725d9301940783dff8ccdcc4a01b9b (diff) | |
vcl: fix libc epoll pwait starved
We call vls_epoll_wait with 0 timeout to process unhandled_evts_vector
in ldp_epoll_pwait_eventfd. But vls_epoll_wait will then call
vppcom_epoll_wait_eventfd to process events in event queue. If there are
continuous events to be handled, then libc_epoll_pwait have no chance to be called.
Type: fix
Signed-off-by: wanghanlin <wanghanlin@corp.netease.com>
Change-Id: Ia4f61d0d438a3475bfde9f6715805274671d4e75
| -rw-r--r-- | src/vcl/ldp.c | 3 | ||||
| -rw-r--r-- | src/vcl/vppcom.c | 3 |
2 files changed, 5 insertions, 1 deletions
diff --git a/src/vcl/ldp.c b/src/vcl/ldp.c index a10d4d02fb4..64a4e7c77db 100644 --- a/src/vcl/ldp.c +++ b/src/vcl/ldp.c @@ -2516,7 +2516,8 @@ ldp_epoll_pwait_eventfd (int epfd, struct epoll_event *events, ldpw->mq_epfd_added = 1; } - rv = vls_epoll_wait (ep_vlsh, events, maxevents, 0); + /* Request to only drain unhandled to prevent libc_epoll_wait starved */ + rv = vls_epoll_wait (ep_vlsh, events, maxevents, -2); if (rv > 0) goto done; else if (PREDICT_FALSE (rv < 0)) diff --git a/src/vcl/vppcom.c b/src/vcl/vppcom.c index cc4464b162e..3e4ba2fb953 100644 --- a/src/vcl/vppcom.c +++ b/src/vcl/vppcom.c @@ -3042,6 +3042,9 @@ vppcom_epoll_wait (uint32_t vep_handle, struct epoll_event *events, } vec_reset_length (wrk->unhandled_evts_vector); } + /* Request to only drain unhandled */ + if ((int) wait_for_time == -2) + return n_evts; if (vcm->cfg.use_mq_eventfd) return vppcom_epoll_wait_eventfd (wrk, events, maxevents, n_evts, |