Re: [PATCH] ath9k_htc: add adaptive usb receive flow control to repair soft lockup with monitor mode

From: Yuwei Zheng
Date: Mon Feb 09 2015 - 03:57:47 EST

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In reply to: Oleksij Rempel: "Re: [PATCH] ath9k_htc: add adaptive usb receive flow control to repair soft lockup with monitor mode"
Next in thread: Oleksij Rempel: "Re: [PATCH] ath9k_htc: add adaptive usb receive flow control to repair soft lockup with monitor mode"
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On ä, 2015-02-06 at 23:24 +0100, Oleksij Rempel wrote:
> formatting of this patch is still badly broken.
> ./scripts/checkpatch.pl ~/Downloads/patch.eml
> ....
> ERROR: DOS line endings
> #442: FILE: drivers/net/wireless/ath/ath9k/htc_drv_txrx.c:1170:
> +^I^IAURFC_STAT_SET(aurfc_submit_delay, delay);^M$
>
> total: 195 errors, 6 warnings, 1 checks, 310 lines checked

Don't save the email as microsoft eml format. The mail tool may
translate it to DOS line endings if you save it as eml format.

I have tested the patch and save it with Evolution as mobox format.
The check result is

total: 0 errors, 0 warnings, 1 checks, 310 lines checked

>
>
> Am 06.02.2015 um 11:46 schrieb yuweizheng@xxxxxxx:
> > From: Yuwei Zheng <yuweizheng@xxxxxxx>
> >
> > In the environment with heavy wifi traffic, set the ar9271 into monitor mode, will
> > trigger a deadloop panic.
> >
> > The ath9k_hif_usb_rx_cb function excute on the interrupt context, and ath9k_rx_tasklet excute
> > on the soft irq context. In other words, the ath9k_hif_usb_rx_cb have more chance to excute than
> > ath9k_rx_tasklet. So in the worst condition, the rx.rxbuf receive list is always full,
> > and the do {}while(true) loop will not be break. The kernel get a soft lockup panic.
> >
> > [59011.007210] BUG: soft lockup - CPU#0 stuck for 23s!
> > [kworker/0:0:30609]
> > [59011.030560] BUG: scheduling while atomic: kworker/0:0/30609/0x40010100
> > [59013.804486] BUG: scheduling while atomic: kworker/0:0/30609/0x40010100
> > [59013.858522] Kernel panic - not syncing: softlockup: hung tasks
> >
> > [59014.038891] Exception stack(0xdf4bbc38 to 0xdf4bbc80)
> > [59014.046834] bc20: de57b950 60000113
> > [59014.059579] bc40: 00000000 bb32bb32 60000113 de57b948 de57b500 dc7bb440 df4bbcd0 00000000
> > [59014.072337] bc60: de57b950 60000113 df4bbcd0 df4bbc80 c04c259d c04c25a0 60000133 ffffffff
> > [59014.085233] [<c04c28db>] (__irq_svc+0x3b/0x5c) from [<c04c25a0>] (_raw_spin_unlock_irqrestore+0xc/0x10)
> > [59014.100437] [<c04c25a0>] (_raw_spin_unlock_irqrestore+0xc/0x10) from [<bf9c2089>] (ath9k_rx_tasklet+0x290/0x490 [ath9k_htc])
> > [59014.118267] [<bf9c2089>] (ath9k_rx_tasklet+0x290/0x490 [ath9k_htc]) from [<c0036d23>] (tasklet_action+0x3b/0x98)
> > [59014.134132] [<c0036d23>] (tasklet_action+0x3b/0x98) from [<c0036709>] (__do_softirq+0x99/0x16c)
> > [59014.147784] [<c0036709>] (__do_softirq+0x99/0x16c) from [<c00369f7>] (irq_exit+0x5b/0x5c)
> > [59014.160653] [<c00369f7>] (irq_exit+0x5b/0x5c) from [<c000cfc3>] (handle_IRQ+0x37/0x78)
> > [59014.173124] [<c000cfc3>] (handle_IRQ+0x37/0x78) from [<c00085df>] (omap3_intc_handle_irq+0x5f/0x68)
> > [59014.187225] [<c00085df>] (omap3_intc_handle_irq+0x5f/0x68) from [<c04c28db>](__irq_svc+0x3b/0x5c)
> >
> > This bug can be see with low performance board, such as uniprocessor beagle bone board.
> >
> > Signed-off-by: Yuwei Zheng <yuweizheng@xxxxxxx>
> >
> > ---
> > drivers/net/wireless/ath/ath9k/hif_usb.c | 74 +++++++++++++++++++++++---
> > drivers/net/wireless/ath/ath9k/hif_usb.h | 9 ++++
> > drivers/net/wireless/ath/ath9k/htc.h | 19 +++++++
> > drivers/net/wireless/ath/ath9k/htc_drv_debug.c | 53 ++++++++++++++++++
> > drivers/net/wireless/ath/ath9k/htc_drv_txrx.c | 44 +++++++++++++++
> > 5 files changed, 192 insertions(+), 7 deletions(-)
> >
> > diff --git a/drivers/net/wireless/ath/ath9k/hif_usb.c b/drivers/net/wireless/ath/ath9k/hif_usb.c
> > index 8e7153b..90ee568 100644
> > --- a/drivers/net/wireless/ath/ath9k/hif_usb.c
> > +++ b/drivers/net/wireless/ath/ath9k/hif_usb.c
> > @@ -640,6 +640,7 @@ static void ath9k_hif_usb_rx_cb(struct urb *urb)
> > struct hif_device_usb *hif_dev =
> > usb_get_intfdata(usb_ifnum_to_if(urb->dev, 0));
> > int ret;
> > + int delay;
> >
> > if (!skb)
> > return;
> > @@ -658,7 +659,6 @@ static void ath9k_hif_usb_rx_cb(struct urb *urb)
> > default:
> > goto resubmit;
> > }
> > -
> > if (likely(urb->actual_length != 0)) {
> > skb_put(skb, urb->actual_length);
> > ath9k_hif_usb_rx_stream(hif_dev, skb);
> > @@ -667,12 +667,22 @@ static void ath9k_hif_usb_rx_cb(struct urb *urb)
> > resubmit:
> > skb_reset_tail_pointer(skb);
> > skb_trim(skb, 0);
> > -
> > - usb_anchor_urb(urb, &hif_dev->rx_submitted);
> > - ret = usb_submit_urb(urb, GFP_ATOMIC);
> > - if (ret) {
> > - usb_unanchor_urb(urb);
> > - goto free;
> > + spin_lock(&hif_dev->aurfc_lock);
> > + if (atomic_read(&hif_dev->aurfc_submit_delay) > 0 &&
> > + hif_dev->aurfc_active == 1) {
> > + usb_anchor_urb(urb, &hif_dev->rx_delayed_submitted);
> > + delay = atomic_read(&hif_dev->aurfc_submit_delay);
> > + schedule_delayed_work(&hif_dev->aurfc_delayed_work,
> > + msecs_to_jiffies(delay));
> > + spin_unlock(&hif_dev->aurfc_lock);
> > + } else {
> > + spin_unlock(&hif_dev->aurfc_lock);
> > + usb_anchor_urb(urb, &hif_dev->rx_submitted);
> > + ret = usb_submit_urb(urb, GFP_ATOMIC);
> > + if (ret) {
> > + usb_unanchor_urb(urb);
> > + goto free;
> > + }
> > }
> >
> > return;
> > @@ -818,9 +828,50 @@ err:
> > return -ENOMEM;
> > }
> >
> > +static void aurfc_submit_handler(struct work_struct *work)
> > +{
> > + struct hif_device_usb *hif_dev =
> > + container_of(work,
> > + struct hif_device_usb,
> > + aurfc_delayed_work.work);
> > +
> > + struct urb *urb = NULL;
> > + struct sk_buff *skb = NULL;
> > + int ret;
> > + int loop_times = 0;
> > +
> > + while (true) {
> > + loop_times++;
> > + if (loop_times > MAX_RX_URB_NUM)
> > + atomic_add(AURFC_STEP,
> > + &hif_dev->aurfc_submit_delay);
> > +
> > + urb = usb_get_from_anchor(
> > + &hif_dev->rx_delayed_submitted);
> > + if (urb) {
> > + skb = (struct sk_buff *)urb->context;
> > + ret = usb_submit_urb(urb, GFP_KERNEL);
> > + if (ret != 0) {
> > + usb_unanchor_urb(urb);
> > + dev_kfree_skb_any(skb);
> > + urb->context = NULL;
> > + }
> > + } else {
> > + break;
> > + }
> > + }
> > +}
> > +
> > static void ath9k_hif_usb_dealloc_rx_urbs(struct hif_device_usb *hif_dev)
> > {
> > + unsigned long flags;
> > +
> > + spin_lock_irqsave(&hif_dev->aurfc_lock, flags);
> > + hif_dev->aurfc_active = 0;
> > + mod_delayed_work(system_wq, &hif_dev->aurfc_delayed_work, 0);
> > + spin_unlock_irqrestore(&hif_dev->aurfc_lock, flags);
> > usb_kill_anchored_urbs(&hif_dev->rx_submitted);
> > + usb_kill_anchored_urbs(&hif_dev->rx_delayed_submitted);
> > }
> >
> > static int ath9k_hif_usb_alloc_rx_urbs(struct hif_device_usb *hif_dev)
> > @@ -830,8 +881,17 @@ static int ath9k_hif_usb_alloc_rx_urbs(struct hif_device_usb *hif_dev)
> > int i, ret;
> >
> > init_usb_anchor(&hif_dev->rx_submitted);
> > + init_usb_anchor(&hif_dev->rx_delayed_submitted);
> > +
> > spin_lock_init(&hif_dev->rx_lock);
> >
> > + /* add for adaptive usb receive control*/
> > + atomic_set(&hif_dev->aurfc_submit_delay, 0);
> > + INIT_DELAYED_WORK(&hif_dev->aurfc_delayed_work,
> > + aurfc_submit_handler);
> > + spin_lock_init(&hif_dev->aurfc_lock);
> > + hif_dev->aurfc_active = 1;
> > +
> > for (i = 0; i < MAX_RX_URB_NUM; i++) {
> >
> > /* Allocate URB */
> > diff --git a/drivers/net/wireless/ath/ath9k/hif_usb.h b/drivers/net/wireless/ath/ath9k/hif_usb.h
> > index 51496e7..2050a74 100644
> > --- a/drivers/net/wireless/ath/ath9k/hif_usb.h
> > +++ b/drivers/net/wireless/ath/ath9k/hif_usb.h
> > @@ -41,6 +41,7 @@
> > #define MAX_RX_URB_NUM 8
> > #define MAX_RX_BUF_SIZE 16384
> > #define MAX_PKT_NUM_IN_TRANSFER 10
> > +#define AURFC_STEP 10 /* ms */
> >
> > #define MAX_REG_OUT_URB_NUM 1
> > #define MAX_REG_IN_URB_NUM 64
> > @@ -98,9 +99,17 @@ struct hif_device_usb {
> > struct hif_usb_tx tx;
> > struct usb_anchor regout_submitted;
> > struct usb_anchor rx_submitted;
> > + struct usb_anchor rx_delayed_submitted;
> > struct usb_anchor reg_in_submitted;
> > struct usb_anchor mgmt_submitted;
> > struct sk_buff *remain_skb;
> > +
> > + /* adaptive usb receive flow control */
> > + struct delayed_work aurfc_delayed_work;
> > + spinlock_t aurfc_lock; /* to protect work */
> > + atomic_t aurfc_submit_delay; /* ms */
> > + int aurfc_active;
> > +
> > const char *fw_name;
> > int rx_remain_len;
> > int rx_pkt_len;
> > diff --git a/drivers/net/wireless/ath/ath9k/htc.h b/drivers/net/wireless/ath/ath9k/htc.h
> > index 9dde265..1586bd2 100644
> > --- a/drivers/net/wireless/ath/ath9k/htc.h
> > +++ b/drivers/net/wireless/ath/ath9k/htc.h
> > @@ -331,6 +331,13 @@ static inline struct ath9k_htc_tx_ctl *HTC_SKB_CB(struct sk_buff *skb)
> >
> > #define TX_QSTAT_INC(q) (priv->debug.tx_stats.queue_stats[q]++)
> >
> > +#define AURFC_STAT_INC(c) \
> > + (hif_dev->htc_handle->drv_priv->debug.aurfc_stats.c++)
> > +#define AURFC_STAT_ADD(c, a) \
> > + (hif_dev->htc_handle->drv_priv->debug.aurfc_stats.c += a)
> > +#define AURFC_STAT_SET(c, a) \
> > + (hif_dev->htc_handle->drv_priv->debug.aurfc_stats.c = a)
> > +
> > void ath9k_htc_err_stat_rx(struct ath9k_htc_priv *priv,
> > struct ath_rx_status *rs);
> >
> > @@ -352,11 +359,20 @@ struct ath_skbrx_stats {
> > u32 skb_dropped;
> > };
> >
> > +struct ath_aurfc_stats {
> > + u32 aurfc_highwater;
> > + u32 aurfc_lowwater;
> > + u32 aurfc_wm_triggered;
> > + u32 aurfc_submit_delay;
> > + u32 aurfc_called;
> > +};
> > +
> > struct ath9k_debug {
> > struct dentry *debugfs_phy;
> > struct ath_tx_stats tx_stats;
> > struct ath_rx_stats rx_stats;
> > struct ath_skbrx_stats skbrx_stats;
> > + struct ath_aurfc_stats aurfc_stats;
> > };
> >
> > void ath9k_htc_get_et_strings(struct ieee80211_hw *hw,
> > @@ -377,6 +393,9 @@ void ath9k_htc_get_et_stats(struct ieee80211_hw *hw,
> >
> > #define TX_QSTAT_INC(c) do { } while (0)
> >
> > +#define AURFC_STAT_INC(c) do {} while (0)
> > +#define AURFC_STAT_ADD(c, a) do {} while (0)
> > +#define AURFC_STAT_SET(c, a) do {} while (0)
> > static inline void ath9k_htc_err_stat_rx(struct ath9k_htc_priv *priv,
> > struct ath_rx_status *rs)
> > {
> > diff --git a/drivers/net/wireless/ath/ath9k/htc_drv_debug.c b/drivers/net/wireless/ath/ath9k/htc_drv_debug.c
> > index 8cef1ed..a6be9be 100644
> > --- a/drivers/net/wireless/ath/ath9k/htc_drv_debug.c
> > +++ b/drivers/net/wireless/ath/ath9k/htc_drv_debug.c
> > @@ -286,6 +286,54 @@ static const struct file_operations fops_skb_rx = {
> > .llseek = default_llseek,
> > };
> >
> > +static ssize_t read_file_aurfc(struct file *file,
> > + char __user *user_buf,
> > + size_t count, loff_t *ppos)
> > +{
> > + struct ath9k_htc_priv *priv = file->private_data;
> > + char *buf;
> > + unsigned int len = 0, size = 1500;
> > + ssize_t retval = 0;
> > +
> > + buf = kzalloc(size, GFP_KERNEL);
> > + if (!buf)
> > + return -ENOMEM;
> > +
> > + len += scnprintf(buf + len, size - len,
> > + "%20s : %10u\n", "High watermark",
> > + priv->debug.aurfc_stats.aurfc_highwater);
> > + len += scnprintf(buf + len, size - len,
> > + "%20s : %10u\n", "Low watermark",
> > + priv->debug.aurfc_stats.aurfc_lowwater);
> > +
> > + len += scnprintf(buf + len, size - len,
> > + "%20s : %10u\n", "WM triggered",
> > + priv->debug.aurfc_stats.aurfc_wm_triggered);
> > +
> > + len += scnprintf(buf + len, size - len,
> > + "%20s : %10u\n", "Handler called",
> > + priv->debug.aurfc_stats.aurfc_called);
> > +
> > + len += scnprintf(buf + len, size - len,
> > + "%20s : %10u\n", "Submit delay",
> > + priv->debug.aurfc_stats.aurfc_submit_delay);
> > + if (len > size)
> > + len = size;
> > +
> > + retval = simple_read_from_buffer(user_buf, count,
> > + ppos, buf, len);
> > + kfree(buf);
> > +
> > + return retval;
> > +}
> > +
> > +static const struct file_operations fops_aurfc = {
> > + .read = read_file_aurfc,
> > + .open = simple_open,
> > + .owner = THIS_MODULE,
> > + .llseek = default_llseek,
> > +};
> > +
> > static ssize_t read_file_slot(struct file *file, char __user *user_buf,
> > size_t count, loff_t *ppos)
> > {
> > @@ -518,7 +566,12 @@ int ath9k_htc_init_debug(struct ath_hw *ah)
> > debugfs_create_file("skb_rx", S_IRUSR, priv->debug.debugfs_phy,
> > priv, &fops_skb_rx);
> >
> > + debugfs_create_file("aurfc_stats", S_IRUSR,
> > + priv->debug.debugfs_phy,
> > + priv, &fops_aurfc);
> > +
> > ath9k_cmn_debug_recv(priv->debug.debugfs_phy, &priv->debug.rx_stats);
> > +
> > ath9k_cmn_debug_phy_err(priv->debug.debugfs_phy, &priv->debug.rx_stats);
> >
> > debugfs_create_file("slot", S_IRUSR, priv->debug.debugfs_phy,
> > diff --git a/drivers/net/wireless/ath/ath9k/htc_drv_txrx.c b/drivers/net/wireless/ath/ath9k/htc_drv_txrx.c
> > index a0f58e2..939d008 100644
> > --- a/drivers/net/wireless/ath/ath9k/htc_drv_txrx.c
> > +++ b/drivers/net/wireless/ath/ath9k/htc_drv_txrx.c
> > @@ -1061,7 +1061,28 @@ void ath9k_rx_tasklet(unsigned long data)
> > unsigned long flags;
> > struct ieee80211_hdr *hdr;
> >
> > + /* add for adaptive usb receive flow control*/
> > + int looptimes = 0;
> > + int highwatermark = ATH9K_HTC_RXBUF*3/4;
> > + int lowwatermark = ATH9K_HTC_RXBUF/32;
> > + unsigned int delay = 0;
> > +
> > + struct htc_target *htc = priv->htc;
> > + struct hif_device_usb *hif_dev = htc->hif_dev;
> > +
> > + AURFC_STAT_SET(aurfc_highwater, highwatermark);
> > + AURFC_STAT_SET(aurfc_lowwater, lowwatermark);
> > +
> > do {
> > + looptimes++;
> > + if (looptimes > highwatermark) {
> > + delay = looptimes*AURFC_STEP;
> > + atomic_set(&hif_dev->aurfc_submit_delay,
> > + delay);
> > + AURFC_STAT_INC(aurfc_wm_triggered);
> > + AURFC_STAT_SET(aurfc_submit_delay, delay);
> > + }
> > +
> > spin_lock_irqsave(&priv->rx.rxbuflock, flags);
> > list_for_each_entry(tmp_buf, &priv->rx.rxbuf, list) {
> > if (tmp_buf->in_process) {
> > @@ -1072,6 +1093,22 @@ void ath9k_rx_tasklet(unsigned long data)
> >
> > if (rxbuf == NULL) {
> > spin_unlock_irqrestore(&priv->rx.rxbuflock, flags);
> > + spin_lock_irqsave(&hif_dev->aurfc_lock,
> > + flags);
> > + if (atomic_read(
> > + &hif_dev->aurfc_submit_delay) > 0 &&
> > + hif_dev->aurfc_active > 0)
> > + mod_delayed_work(system_wq,
> > + &hif_dev->aurfc_delayed_work,
> > + 0);
> > + spin_unlock_irqrestore(&hif_dev->aurfc_lock,
> > + flags);
> > + if (looptimes < lowwatermark) {
> > + atomic_set(&hif_dev->aurfc_submit_delay
> > + , 0);
> > + AURFC_STAT_SET(aurfc_submit_delay,
> > + 0);
> > + }
> > break;
> > }
> >
> > @@ -1114,6 +1151,10 @@ void ath9k_htc_rxep(void *drv_priv, struct sk_buff *skb,
> > struct ath_common *common = ath9k_hw_common(ah);
> > struct ath9k_htc_rxbuf *rxbuf = NULL, *tmp_buf = NULL;
> >
> > + struct htc_target *htc = priv->htc;
> > + struct hif_device_usb *hif_dev = htc->hif_dev;
> > + int delay = ATH9K_HTC_RXBUF * AURFC_STEP;
> > +
> > spin_lock(&priv->rx.rxbuflock);
> > list_for_each_entry(tmp_buf, &priv->rx.rxbuf, list) {
> > if (!tmp_buf->in_process) {
> > @@ -1124,6 +1165,9 @@ void ath9k_htc_rxep(void *drv_priv, struct sk_buff *skb,
> > spin_unlock(&priv->rx.rxbuflock);
> >
> > if (rxbuf == NULL) {
> > + atomic_set(&hif_dev->aurfc_submit_delay, delay);
> > + AURFC_STAT_INC(aurfc_wm_triggered);
> > + AURFC_STAT_SET(aurfc_submit_delay, delay);
> > ath_dbg(common, ANY, "No free RX buffer\n");
> > goto err;
> > }
> >
>
>

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Next message: Greg Kroah-Hartman: "[PATCH 3.14 11/20] nilfs2: fix deadlock of segment constructor over I_SYNC flag"
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In reply to: Oleksij Rempel: "Re: [PATCH] ath9k_htc: add adaptive usb receive flow control to repair soft lockup with monitor mode"
Next in thread: Oleksij Rempel: "Re: [PATCH] ath9k_htc: add adaptive usb receive flow control to repair soft lockup with monitor mode"
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