From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id E04EE2E8DE8; Tue, 17 Jun 2025 16:33:23 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1750178004; cv=none; b=Kq8cywSpyJ9z/0l/dEY7Dh98qpPPofboO272a/ck4cL+CpwRxhG8unYw0K42eRIXfEDnDxHUgVNN8N8YwTGKtMTwsrfrHCGajJyPvVFfTN/TK3umPKmToi3ucgGM/x+cMDl8OM/fI2mLd8s2at4Uj1qm+OA6VkoDr1PIZjGpoP4= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1750178004; c=relaxed/simple; bh=FbkA4QdGr/B6K2hejlT0b94OTqWCoXtZs9ueojjLRUc=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=WOAAIu1Vr6XNG0bFpdPC7J6wBRiMqhukveMTUO/g5HTVhDRc3ZuQfwpcEYW3dKfSFWUla9cTDr+5gLWk3btOAKwPkeiqVyTqM7hon3sDJQCbqMuJx8U6W8oFUFxFv0tcIZrP5YWJZqUbM1BrSu1VDbDKc3arqrdk6H75Y4b+xAY= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=UVORwsDv; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="UVORwsDv" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 4FDE9C4CEE7; Tue, 17 Jun 2025 16:33:23 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1750178003; bh=FbkA4QdGr/B6K2hejlT0b94OTqWCoXtZs9ueojjLRUc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=UVORwsDvwhwYZh5I8dTmgt3NNEKd/8azD9aQF2dI9eW8sLPoR7DHiHb1vNJg5T7Vc vlxEHn4Aax1hEz9vbPbCFc4h8/0K3Yin3VvaaZUo/GlKlevJ6K7o4OOHQzAP2WJjK/ wwgFp9AT+9PFy092D0WN7MD2c6JjCceB47XAXNhs= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Yury Vostrikov , Baochen Qiang , Vasanthakumar Thiagarajan , Jeff Johnson , Sasha Levin Subject: [PATCH 6.12 430/512] wifi: ath11k: avoid burning CPU in ath11k_debugfs_fw_stats_request() Date: Tue, 17 Jun 2025 17:26:36 +0200 Message-ID: <20250617152436.998281921@linuxfoundation.org> X-Mailer: git-send-email 2.49.0 In-Reply-To: <20250617152419.512865572@linuxfoundation.org> References: <20250617152419.512865572@linuxfoundation.org> User-Agent: quilt/0.68 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.12-stable review patch. If anyone has any objections, please let me know. ------------------ From: Baochen Qiang [ Upstream commit 9f6e82d11bb9692a90d20b10f87345598945c803 ] 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. Change to completion mechanism 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 Closes: https://lore.kernel.org/all/7324ac7a-8b7a-42a5-aa19-de52138ff638@app.fastmail.com/ # [1] Signed-off-by: Baochen Qiang Reviewed-by: Vasanthakumar Thiagarajan Link: https://patch.msgid.link/20250220082448.31039-2-quic_bqiang@quicinc.com Signed-off-by: Jeff Johnson Signed-off-by: Sasha Levin --- drivers/net/wireless/ath/ath11k/core.c | 1 + drivers/net/wireless/ath/ath11k/core.h | 2 +- drivers/net/wireless/ath/ath11k/debugfs.c | 38 +++++++++-------------- drivers/net/wireless/ath/ath11k/mac.c | 2 +- drivers/net/wireless/ath/ath11k/wmi.c | 2 +- 5 files changed, 18 insertions(+), 27 deletions(-) diff --git a/drivers/net/wireless/ath/ath11k/core.c b/drivers/net/wireless/ath/ath11k/core.c index 674c4763333f3..d08f40f77031a 100644 --- a/drivers/net/wireless/ath/ath11k/core.c +++ b/drivers/net/wireless/ath/ath11k/core.c @@ -855,6 +855,7 @@ void ath11k_fw_stats_init(struct ath11k *ar) INIT_LIST_HEAD(&ar->fw_stats.bcn); init_completion(&ar->fw_stats_complete); + init_completion(&ar->fw_stats_done); } void ath11k_fw_stats_free(struct ath11k_fw_stats *stats) diff --git a/drivers/net/wireless/ath/ath11k/core.h b/drivers/net/wireless/ath/ath11k/core.h index 09c37e19a1680..bbf2ccfee3fc0 100644 --- a/drivers/net/wireless/ath/ath11k/core.h +++ b/drivers/net/wireless/ath/ath11k/core.h @@ -780,7 +780,7 @@ struct ath11k { u8 alpha2[REG_ALPHA2_LEN + 1]; struct ath11k_fw_stats fw_stats; struct completion fw_stats_complete; - bool fw_stats_done; + struct completion fw_stats_done; /* protected by conf_mutex */ bool ps_state_enable; diff --git a/drivers/net/wireless/ath/ath11k/debugfs.c b/drivers/net/wireless/ath/ath11k/debugfs.c index bf192529e3fe2..1d03e3aab011d 100644 --- a/drivers/net/wireless/ath/ath11k/debugfs.c +++ b/drivers/net/wireless/ath/ath11k/debugfs.c @@ -1,7 +1,7 @@ // SPDX-License-Identifier: BSD-3-Clause-Clear /* * Copyright (c) 2018-2020 The Linux Foundation. All rights reserved. - * Copyright (c) 2021-2024 Qualcomm Innovation Center, Inc. All rights reserved. + * Copyright (c) 2021-2025 Qualcomm Innovation Center, Inc. All rights reserved. */ #include @@ -96,7 +96,6 @@ void ath11k_debugfs_add_dbring_entry(struct ath11k *ar, static void ath11k_debugfs_fw_stats_reset(struct ath11k *ar) { spin_lock_bh(&ar->data_lock); - ar->fw_stats_done = false; ath11k_fw_stats_pdevs_free(&ar->fw_stats.pdevs); ath11k_fw_stats_vdevs_free(&ar->fw_stats.vdevs); spin_unlock_bh(&ar->data_lock); @@ -114,7 +113,7 @@ void ath11k_debugfs_fw_stats_process(struct ath11k *ar, struct ath11k_fw_stats * /* WMI_REQUEST_PDEV_STAT request has been already processed */ if (stats->stats_id == WMI_REQUEST_RSSI_PER_CHAIN_STAT) { - ar->fw_stats_done = true; + complete(&ar->fw_stats_done); return; } @@ -138,7 +137,7 @@ void ath11k_debugfs_fw_stats_process(struct ath11k *ar, struct ath11k_fw_stats * &ar->fw_stats.vdevs); if (is_end) { - ar->fw_stats_done = true; + complete(&ar->fw_stats_done); num_vdev = 0; } return; @@ -158,7 +157,7 @@ void ath11k_debugfs_fw_stats_process(struct ath11k *ar, struct ath11k_fw_stats * &ar->fw_stats.bcn); if (is_end) { - ar->fw_stats_done = true; + complete(&ar->fw_stats_done); num_bcn = 0; } } @@ -168,21 +167,15 @@ static int ath11k_debugfs_fw_stats_request(struct ath11k *ar, struct stats_request_params *req_param) { struct ath11k_base *ab = ar->ab; - unsigned long timeout, time_left; + unsigned long time_left; int ret; lockdep_assert_held(&ar->conf_mutex); - /* FW stats can get split when exceeding the stats data buffer limit. - * In that case, since there is no end marking for the back-to-back - * received 'update stats' event, we keep a 3 seconds timeout in case, - * fw_stats_done is not marked yet - */ - timeout = jiffies + secs_to_jiffies(3); - ath11k_debugfs_fw_stats_reset(ar); reinit_completion(&ar->fw_stats_complete); + reinit_completion(&ar->fw_stats_done); ret = ath11k_wmi_send_stats_request_cmd(ar, req_param); @@ -193,21 +186,18 @@ static int ath11k_debugfs_fw_stats_request(struct ath11k *ar, } time_left = wait_for_completion_timeout(&ar->fw_stats_complete, 1 * HZ); - if (!time_left) return -ETIMEDOUT; - for (;;) { - if (time_after(jiffies, timeout)) - break; + /* FW stats can get split when exceeding the stats data buffer limit. + * In that case, since there is no end marking for the back-to-back + * received 'update stats' event, we keep a 3 seconds timeout in case, + * fw_stats_done is not marked yet + */ + time_left = wait_for_completion_timeout(&ar->fw_stats_done, 3 * HZ); + if (!time_left) + return -ETIMEDOUT; - spin_lock_bh(&ar->data_lock); - if (ar->fw_stats_done) { - spin_unlock_bh(&ar->data_lock); - break; - } - spin_unlock_bh(&ar->data_lock); - } return 0; } diff --git a/drivers/net/wireless/ath/ath11k/mac.c b/drivers/net/wireless/ath/ath11k/mac.c index f8068d2e848c3..78c825244613b 100644 --- a/drivers/net/wireless/ath/ath11k/mac.c +++ b/drivers/net/wireless/ath/ath11k/mac.c @@ -9331,11 +9331,11 @@ static int ath11k_fw_stats_request(struct ath11k *ar, lockdep_assert_held(&ar->conf_mutex); spin_lock_bh(&ar->data_lock); - ar->fw_stats_done = false; ath11k_fw_stats_pdevs_free(&ar->fw_stats.pdevs); spin_unlock_bh(&ar->data_lock); reinit_completion(&ar->fw_stats_complete); + reinit_completion(&ar->fw_stats_done); ret = ath11k_wmi_send_stats_request_cmd(ar, req_param); if (ret) { diff --git a/drivers/net/wireless/ath/ath11k/wmi.c b/drivers/net/wireless/ath/ath11k/wmi.c index 87abfa5475295..e2203f668d7cf 100644 --- a/drivers/net/wireless/ath/ath11k/wmi.c +++ b/drivers/net/wireless/ath/ath11k/wmi.c @@ -8188,7 +8188,7 @@ static void ath11k_update_stats_event(struct ath11k_base *ab, struct sk_buff *sk */ if (stats.stats_id == WMI_REQUEST_PDEV_STAT) { list_splice_tail_init(&stats.pdevs, &ar->fw_stats.pdevs); - ar->fw_stats_done = true; + complete(&ar->fw_stats_done); goto complete; } -- 2.39.5