| Message ID | 1431743367-10059-1-git-send-email-Larry.Finger@lwfinger.net (mailing list archive) |
|---|---|
| State | Accepted |
| Delegated to: | Kalle Valo |
| Headers | show |
Larry Finger <Larry.Finger@lwfinger.net> writes: > From: Vincent Fann <vincent_fann@realtek.com> > > Several of these drivers have there TX randomly blocked for 3~5 seconds while > measuring tx throughput (iperf). The root couse happens in rtl_pci_flush(). > The function uses a while-loop to wait for TX queue length to decrease to 0. > The TX queue length counts the number of packets that are queued in the driver. > The driver relys on the TX OK interrupt to return skb and reduce TX queue length. > > The interrupt subroutine disables interupts, reads the interrupt registers, and > then clears the registers in the beginning of _rtl_pci_interrupt(). After all > interupts process are finished, the driver invokes enable_interrupt() to enable > interupts. This behavior is normal for an interrupt subroutine. > > But enable_interrupt() invokes clear_interrupt() again. This unexpected interrupt > clearing may cleari me fresh TX OK interrupts. These missing interrupts cause TX > queue length to never reduce to 0i, which causes rtl_pci_flush() to be stuck in > unterminated while-loop. > > This patch removes clear_interrupt() in enable_interrupt() to avoid this behavior. > > Signed-off-by: Vincent Fann <vincent_fann@realtek.com> > Signed-off-by: Shao Fu <shaofu@realtek.com> > Signed-off-by: Larry Finger <Larry.Finger@lwfinger.net> > Cc: Stable <stable@vger.kernel.org> [3.18+] > --- > > Kalle, > > This patch is a little large for the current kernel and stable; however, it only > deletes code that is clearly wrong. I hope it will be OK. This isn't a recent regression nor a crasher (or similar) so I can't really justify to send this to 4.1 this late. The way I see it this could easily wait for 4.2, right?
On 05/20/2015 08:53 AM, Kalle Valo wrote: > Larry Finger <Larry.Finger@lwfinger.net> writes: > >> From: Vincent Fann <vincent_fann@realtek.com> >> >> Several of these drivers have there TX randomly blocked for 3~5 seconds while >> measuring tx throughput (iperf). The root couse happens in rtl_pci_flush(). >> The function uses a while-loop to wait for TX queue length to decrease to 0. >> The TX queue length counts the number of packets that are queued in the driver. >> The driver relys on the TX OK interrupt to return skb and reduce TX queue length. >> >> The interrupt subroutine disables interupts, reads the interrupt registers, and >> then clears the registers in the beginning of _rtl_pci_interrupt(). After all >> interupts process are finished, the driver invokes enable_interrupt() to enable >> interupts. This behavior is normal for an interrupt subroutine. >> >> But enable_interrupt() invokes clear_interrupt() again. This unexpected interrupt >> clearing may cleari me fresh TX OK interrupts. These missing interrupts cause TX >> queue length to never reduce to 0i, which causes rtl_pci_flush() to be stuck in >> unterminated while-loop. >> >> This patch removes clear_interrupt() in enable_interrupt() to avoid this behavior. >> >> Signed-off-by: Vincent Fann <vincent_fann@realtek.com> >> Signed-off-by: Shao Fu <shaofu@realtek.com> >> Signed-off-by: Larry Finger <Larry.Finger@lwfinger.net> >> Cc: Stable <stable@vger.kernel.org> [3.18+] >> --- >> >> Kalle, >> >> This patch is a little large for the current kernel and stable; however, it only >> deletes code that is clearly wrong. I hope it will be OK. > > This isn't a recent regression nor a crasher (or similar) so I can't > really justify to send this to 4.1 this late. The way I see it this > could easily wait for 4.2, right? OK. If any user complains about the 3-5 second hang, I'll refer then to the out-of-kernel repo for a fix. Larry -- To unsubscribe from this list: send the line "unsubscribe linux-wireless" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
> From: Vincent Fann <vincent_fann@realtek.com> > > Several of these drivers have there TX randomly blocked for 3~5 seconds while > measuring tx throughput (iperf). The root couse happens in rtl_pci_flush(). > The function uses a while-loop to wait for TX queue length to decrease to 0. > The TX queue length counts the number of packets that are queued in the driver. > The driver relys on the TX OK interrupt to return skb and reduce TX queue length. > > The interrupt subroutine disables interupts, reads the interrupt registers, and > then clears the registers in the beginning of _rtl_pci_interrupt(). After all > interupts process are finished, the driver invokes enable_interrupt() to enable > interupts. This behavior is normal for an interrupt subroutine. > > But enable_interrupt() invokes clear_interrupt() again. This unexpected interrupt > clearing may cleari me fresh TX OK interrupts. These missing interrupts cause TX > queue length to never reduce to 0i, which causes rtl_pci_flush() to be stuck in > unterminated while-loop. > > This patch removes clear_interrupt() in enable_interrupt() to avoid this behavior. > > Signed-off-by: Vincent Fann <vincent_fann@realtek.com> > Signed-off-by: Shao Fu <shaofu@realtek.com> > Signed-off-by: Larry Finger <Larry.Finger@lwfinger.net> > Cc: Stable <stable@vger.kernel.org> [3.18+] Thanks, applied to wireless-drivers-next.git. Kalle Valo -- To unsubscribe from this list: send the line "unsubscribe linux-wireless" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/drivers/net/wireless/rtlwifi/rtl8188ee/hw.c b/drivers/net/wireless/rtlwifi/rtl8188ee/hw.c index 86ce5b1..e5d8108f 100644 --- a/drivers/net/wireless/rtlwifi/rtl8188ee/hw.c +++ b/drivers/net/wireless/rtlwifi/rtl8188ee/hw.c @@ -1354,27 +1354,11 @@ void rtl88ee_set_qos(struct ieee80211_hw *hw, int aci) } } -static void rtl88ee_clear_interrupt(struct ieee80211_hw *hw) -{ - struct rtl_priv *rtlpriv = rtl_priv(hw); - u32 tmp; - - tmp = rtl_read_dword(rtlpriv, REG_HISR); - rtl_write_dword(rtlpriv, REG_HISR, tmp); - - tmp = rtl_read_dword(rtlpriv, REG_HISRE); - rtl_write_dword(rtlpriv, REG_HISRE, tmp); - - tmp = rtl_read_dword(rtlpriv, REG_HSISR); - rtl_write_dword(rtlpriv, REG_HSISR, tmp); -} - void rtl88ee_enable_interrupt(struct ieee80211_hw *hw) { struct rtl_priv *rtlpriv = rtl_priv(hw); struct rtl_pci *rtlpci = rtl_pcidev(rtl_pcipriv(hw)); - rtl88ee_clear_interrupt(hw);/*clear it here first*/ rtl_write_dword(rtlpriv, REG_HIMR, rtlpci->irq_mask[0] & 0xFFFFFFFF); rtl_write_dword(rtlpriv, REG_HIMRE, diff --git a/drivers/net/wireless/rtlwifi/rtl8192ee/hw.c b/drivers/net/wireless/rtlwifi/rtl8192ee/hw.c index 2786ccf..0586ecb 100644 --- a/drivers/net/wireless/rtlwifi/rtl8192ee/hw.c +++ b/drivers/net/wireless/rtlwifi/rtl8192ee/hw.c @@ -1584,28 +1584,11 @@ void rtl92ee_set_qos(struct ieee80211_hw *hw, int aci) } } -static void rtl92ee_clear_interrupt(struct ieee80211_hw *hw) -{ - struct rtl_priv *rtlpriv = rtl_priv(hw); - u32 tmp; - - tmp = rtl_read_dword(rtlpriv, REG_HISR); - rtl_write_dword(rtlpriv, REG_HISR, tmp); - - tmp = rtl_read_dword(rtlpriv, REG_HISRE); - rtl_write_dword(rtlpriv, REG_HISRE, tmp); - - tmp = rtl_read_dword(rtlpriv, REG_HSISR); - rtl_write_dword(rtlpriv, REG_HSISR, tmp); -} - void rtl92ee_enable_interrupt(struct ieee80211_hw *hw) { struct rtl_priv *rtlpriv = rtl_priv(hw); struct rtl_pci *rtlpci = rtl_pcidev(rtl_pcipriv(hw)); - rtl92ee_clear_interrupt(hw);/*clear it here first*/ - rtl_write_dword(rtlpriv, REG_HIMR, rtlpci->irq_mask[0] & 0xFFFFFFFF); rtl_write_dword(rtlpriv, REG_HIMRE, rtlpci->irq_mask[1] & 0xFFFFFFFF); rtlpci->irq_enabled = true; diff --git a/drivers/net/wireless/rtlwifi/rtl8723ae/hw.c b/drivers/net/wireless/rtlwifi/rtl8723ae/hw.c index 67bb47d..a4b7eac 100644 --- a/drivers/net/wireless/rtlwifi/rtl8723ae/hw.c +++ b/drivers/net/wireless/rtlwifi/rtl8723ae/hw.c @@ -1258,18 +1258,6 @@ void rtl8723e_set_qos(struct ieee80211_hw *hw, int aci) } } -static void rtl8723e_clear_interrupt(struct ieee80211_hw *hw) -{ - struct rtl_priv *rtlpriv = rtl_priv(hw); - u32 tmp; - - tmp = rtl_read_dword(rtlpriv, REG_HISR); - rtl_write_dword(rtlpriv, REG_HISR, tmp); - - tmp = rtl_read_dword(rtlpriv, REG_HISRE); - rtl_write_dword(rtlpriv, REG_HISRE, tmp); -} - void rtl8723e_enable_interrupt(struct ieee80211_hw *hw) { struct rtl_priv *rtlpriv = rtl_priv(hw); @@ -1284,7 +1272,6 @@ void rtl8723e_disable_interrupt(struct ieee80211_hw *hw) { struct rtl_priv *rtlpriv = rtl_priv(hw); struct rtl_pci *rtlpci = rtl_pcidev(rtl_pcipriv(hw)); - rtl8723e_clear_interrupt(hw);/*clear it here first*/ rtl_write_dword(rtlpriv, 0x3a8, IMR8190_DISABLED); rtl_write_dword(rtlpriv, 0x3ac, IMR8190_DISABLED); rtlpci->irq_enabled = false; diff --git a/drivers/net/wireless/rtlwifi/rtl8723be/hw.c b/drivers/net/wireless/rtlwifi/rtl8723be/hw.c index b681af3..b941726 100644 --- a/drivers/net/wireless/rtlwifi/rtl8723be/hw.c +++ b/drivers/net/wireless/rtlwifi/rtl8723be/hw.c @@ -1634,28 +1634,11 @@ void rtl8723be_set_qos(struct ieee80211_hw *hw, int aci) } } -static void rtl8723be_clear_interrupt(struct ieee80211_hw *hw) -{ - struct rtl_priv *rtlpriv = rtl_priv(hw); - u32 tmp; - - tmp = rtl_read_dword(rtlpriv, REG_HISR); - rtl_write_dword(rtlpriv, REG_HISR, tmp); - - tmp = rtl_read_dword(rtlpriv, REG_HISRE); - rtl_write_dword(rtlpriv, REG_HISRE, tmp); - - tmp = rtl_read_dword(rtlpriv, REG_HSISR); - rtl_write_dword(rtlpriv, REG_HSISR, tmp); -} - void rtl8723be_enable_interrupt(struct ieee80211_hw *hw) { struct rtl_priv *rtlpriv = rtl_priv(hw); struct rtl_pci *rtlpci = rtl_pcidev(rtl_pcipriv(hw)); - rtl8723be_clear_interrupt(hw);/*clear it here first*/ - rtl_write_dword(rtlpriv, REG_HIMR, rtlpci->irq_mask[0] & 0xFFFFFFFF); rtl_write_dword(rtlpriv, REG_HIMRE, rtlpci->irq_mask[1] & 0xFFFFFFFF); rtlpci->irq_enabled = true; diff --git a/drivers/net/wireless/rtlwifi/rtl8821ae/hw.c b/drivers/net/wireless/rtlwifi/rtl8821ae/hw.c index 8704eee..57966e3 100644 --- a/drivers/net/wireless/rtlwifi/rtl8821ae/hw.c +++ b/drivers/net/wireless/rtlwifi/rtl8821ae/hw.c @@ -2253,31 +2253,11 @@ void rtl8821ae_set_qos(struct ieee80211_hw *hw, int aci) } } -static void rtl8821ae_clear_interrupt(struct ieee80211_hw *hw) -{ - struct rtl_priv *rtlpriv = rtl_priv(hw); - u32 tmp; - tmp = rtl_read_dword(rtlpriv, REG_HISR); - /*printk("clear interrupt first:\n"); - printk("0x%x = 0x%08x\n",REG_HISR, tmp);*/ - rtl_write_dword(rtlpriv, REG_HISR, tmp); - - tmp = rtl_read_dword(rtlpriv, REG_HISRE); - /*printk("0x%x = 0x%08x\n",REG_HISRE, tmp);*/ - rtl_write_dword(rtlpriv, REG_HISRE, tmp); - - tmp = rtl_read_dword(rtlpriv, REG_HSISR); - /*printk("0x%x = 0x%08x\n",REG_HSISR, tmp);*/ - rtl_write_dword(rtlpriv, REG_HSISR, tmp); -} - void rtl8821ae_enable_interrupt(struct ieee80211_hw *hw) { struct rtl_priv *rtlpriv = rtl_priv(hw); struct rtl_pci *rtlpci = rtl_pcidev(rtl_pcipriv(hw)); - rtl8821ae_clear_interrupt(hw);/*clear it here first*/ - rtl_write_dword(rtlpriv, REG_HIMR, rtlpci->irq_mask[0] & 0xFFFFFFFF); rtl_write_dword(rtlpriv, REG_HIMRE, rtlpci->irq_mask[1] & 0xFFFFFFFF); rtlpci->irq_enabled = true;