diff options
| -rw-r--r-- | net/core/dev.c | 45 | ||||
| -rwxr-xr-x | tools/testing/selftests/net/nl_netdev.py | 38 |
2 files changed, 79 insertions, 4 deletions
diff --git a/net/core/dev.c b/net/core/dev.c index be97c440ecd5..5baa4691074f 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -6926,6 +6926,43 @@ static enum hrtimer_restart napi_watchdog(struct hrtimer *timer) return HRTIMER_NORESTART; } +static void napi_stop_kthread(struct napi_struct *napi) +{ + unsigned long val, new; + + /* Wait until the napi STATE_THREADED is unset. */ + while (true) { + val = READ_ONCE(napi->state); + + /* If napi kthread own this napi or the napi is idle, + * STATE_THREADED can be unset here. + */ + if ((val & NAPIF_STATE_SCHED_THREADED) || + !(val & NAPIF_STATE_SCHED)) { + new = val & (~NAPIF_STATE_THREADED); + } else { + msleep(20); + continue; + } + + if (try_cmpxchg(&napi->state, &val, new)) + break; + } + + /* Once STATE_THREADED is unset, wait for SCHED_THREADED to be unset by + * the kthread. + */ + while (true) { + if (!test_bit(NAPIF_STATE_SCHED_THREADED, &napi->state)) + break; + + msleep(20); + } + + kthread_stop(napi->thread); + napi->thread = NULL; +} + int dev_set_threaded(struct net_device *dev, bool threaded) { struct napi_struct *napi; @@ -6961,8 +6998,12 @@ int dev_set_threaded(struct net_device *dev, bool threaded) * softirq mode will happen in the next round of napi_schedule(). * This should not cause hiccups/stalls to the live traffic. */ - list_for_each_entry(napi, &dev->napi_list, dev_list) - assign_bit(NAPI_STATE_THREADED, &napi->state, threaded); + list_for_each_entry(napi, &dev->napi_list, dev_list) { + if (!threaded && napi->thread) + napi_stop_kthread(napi); + else + assign_bit(NAPI_STATE_THREADED, &napi->state, threaded); + } return err; } diff --git a/tools/testing/selftests/net/nl_netdev.py b/tools/testing/selftests/net/nl_netdev.py index beaee5e4e2aa..c9109627a741 100755 --- a/tools/testing/selftests/net/nl_netdev.py +++ b/tools/testing/selftests/net/nl_netdev.py @@ -2,8 +2,9 @@ # SPDX-License-Identifier: GPL-2.0 import time +from os import system from lib.py import ksft_run, ksft_exit, ksft_pr -from lib.py import ksft_eq, ksft_ge, ksft_busy_wait +from lib.py import ksft_eq, ksft_ge, ksft_ne, ksft_busy_wait from lib.py import NetdevFamily, NetdevSimDev, ip @@ -34,6 +35,39 @@ def napi_list_check(nf) -> None: ksft_eq(len(napis), 100, comment=f"queue count after reset queue {q} mode {i}") +def dev_set_threaded(nf) -> None: + """ + Test that verifies various cases of napi threaded + set and unset at device level using sysfs. + """ + with NetdevSimDev(queue_count=2) as nsimdev: + nsim = nsimdev.nsims[0] + + ip(f"link set dev {nsim.ifname} up") + + napis = nf.napi_get({'ifindex': nsim.ifindex}, dump=True) + ksft_eq(len(napis), 2) + + napi0_id = napis[0]['id'] + napi1_id = napis[1]['id'] + + # set threaded + system(f"echo 1 > /sys/class/net/{nsim.ifname}/threaded") + + # check napi threaded is set for both napis + napi0 = nf.napi_get({'id': napi0_id}) + ksft_ne(napi0.get('pid'), None) + napi1 = nf.napi_get({'id': napi1_id}) + ksft_ne(napi1.get('pid'), None) + + # unset threaded + system(f"echo 0 > /sys/class/net/{nsim.ifname}/threaded") + + # check napi threaded is unset for both napis + napi0 = nf.napi_get({'id': napi0_id}) + ksft_eq(napi0.get('pid'), None) + napi1 = nf.napi_get({'id': napi1_id}) + ksft_eq(napi1.get('pid'), None) def nsim_rxq_reset_down(nf) -> None: """ @@ -122,7 +156,7 @@ def page_pool_check(nf) -> None: def main() -> None: nf = NetdevFamily() ksft_run([empty_check, lo_check, page_pool_check, napi_list_check, - nsim_rxq_reset_down], + dev_set_threaded, nsim_rxq_reset_down], args=(nf, )) ksft_exit() |