Under synflood conditions binding defense_work to system_long_wq may pin it to a saturated CPU.
We've observed improved throughtput on a DPDK/VPP application with this change. We attribute this to the reduced context switching. The defense_work handler has no per-CPU data dependencies and no cache locality requirements that would justify this. Signed-off-by: Ismael Luceno <[email protected]> --- Depends-on: wq/for-7.1 c116737e972e ("workqueue: Add system_dfl_long_wq for long unbound works") net/netfilter/ipvs/ip_vs_ctl.c | 6 +++--- net/netfilter/ipvs/ip_vs_est.c | 2 +- 2 files changed, 4 insertions(+), 4 deletions(-) diff --git a/net/netfilter/ipvs/ip_vs_ctl.c b/net/netfilter/ipvs/ip_vs_ctl.c index 35642de2a0fe..948ae5882a70 100644 --- a/net/netfilter/ipvs/ip_vs_ctl.c +++ b/net/netfilter/ipvs/ip_vs_ctl.c @@ -234,7 +234,7 @@ #define DEFENSE_TIMER_PERIOD 1*HZ update_defense_level(ipvs); if (atomic_read(&ipvs->dropentry)) ip_vs_random_dropentry(ipvs); - queue_delayed_work(system_long_wq, &ipvs->defense_work, + queue_delayed_work(system_dfl_long_wq, &ipvs->defense_work, DEFENSE_TIMER_PERIOD); } #endif @@ -273,7 +273,7 @@ #define DEFENSE_TIMER_PERIOD 1*HZ atomic_set(&ipvs->est_genid_done, genid); if (repeat) - queue_delayed_work(system_long_wq, &ipvs->est_reload_work, + queue_delayed_work(system_dfl_long_wq, &ipvs->est_reload_work, delay); unlock: @@ -4377,7 +4377,7 @@ do_ip_vs_get_ctl(struct sock *sk, int cmd, void __user *user, int *len) goto err; /* Schedule defense work */ - queue_delayed_work(system_long_wq, &ipvs->defense_work, + queue_delayed_work(system_dfl_long_wq, &ipvs->defense_work, DEFENSE_TIMER_PERIOD); return 0; diff --git a/net/netfilter/ipvs/ip_vs_est.c b/net/netfilter/ipvs/ip_vs_est.c index b17de33314da..454ea24828cc 100644 --- a/net/netfilter/ipvs/ip_vs_est.c +++ b/net/netfilter/ipvs/ip_vs_est.c @@ -235,7 +235,7 @@ #define pr_fmt(fmt) "IPVS: " fmt ip_vs_est_stopped_recalc(ipvs); /* Bump the kthread configuration genid */ atomic_inc(&ipvs->est_genid); - queue_delayed_work(system_long_wq, &ipvs->est_reload_work, 0); + queue_delayed_work(system_dfl_long_wq, &ipvs->est_reload_work, 0); } /* Start kthread task with current configuration */
