| Message ID | 20241113015631.3105-2-quic_bqiang@quicinc.com |
|---|---|
| State | New |
| Headers | show |
| Series | [1/6] wifi: ath11k: avoid burning CPU in ath11k_debugfs_fw_stats_request() | expand |
diff --git a/drivers/net/wireless/ath/ath11k/debugfs.c b/drivers/net/wireless/ath/ath11k/debugfs.c index 57281a135dd7..a5e0f2092da5 100644 --- a/drivers/net/wireless/ath/ath11k/debugfs.c +++ b/drivers/net/wireless/ath/ath11k/debugfs.c @@ -207,6 +207,9 @@ static int ath11k_debugfs_fw_stats_request(struct ath11k *ar, break; } spin_unlock_bh(&ar->data_lock); + + /* 100ms is empirical, change if required */ + msleep(100); } return 0; }
We get report [1] that CPU is running a hot loop in ath11k_debugfs_fw_stats_request(): 94.60% 0.00% i3status [kernel.kallsyms] [k] do_syscall_64 | --94.60%--do_syscall_64 | --94.55%--__sys_sendmsg ___sys_sendmsg ____sys_sendmsg netlink_sendmsg netlink_unicast genl_rcv netlink_rcv_skb genl_rcv_msg | --94.55%--genl_family_rcv_msg_dumpit __netlink_dump_start netlink_dump genl_dumpit nl80211_dump_station | --94.55%--ieee80211_dump_station sta_set_sinfo | --94.55%--ath11k_mac_op_sta_statistics ath11k_debugfs_get_fw_stats | --94.55%--ath11k_debugfs_fw_stats_request | |--41.73%--_raw_spin_lock_bh | |--22.74%--__local_bh_enable_ip | |--9.22%--_raw_spin_unlock_bh | --6.66%--srso_alias_safe_ret This is because, if for whatever reason ar->fw_stats_done is not set by ath11k_update_stats_event(), ath11k_debugfs_fw_stats_request() won't yield CPU before an up to 3s timeout. Add 100ms sleep to avoid CPU burning. Tested-on: WCN6855 hw2.0 PCI WLAN.HSP.1.1-03125-QCAHSPSWPL_V1_V2_SILICONZ_LITE-3.6510.37 Fixes: d5c65159f289 ("ath11k: driver for Qualcomm IEEE 802.11ax devices") Reported-by: Yury Vostrikov <mon@unformed.ru> Closes: https://lore.kernel.org/all/7324ac7a-8b7a-42a5-aa19-de52138ff638@app.fastmail.com/ # [1] Signed-off-by: Baochen Qiang <quic_bqiang@quicinc.com> --- drivers/net/wireless/ath/ath11k/debugfs.c | 3 +++ 1 file changed, 3 insertions(+)