diff mbox series

[RFC,6/6] r8169: remove ASPM restrictions now that ASPM is disabled during NAPI poll

Message ID 2d61ba5a-9a2c-28c3-4a1b-a81a3f34af3d@gmail.com (mailing list archive)
State Superseded
Delegated to: Netdev Maintainers
Headers show
Series r8169: disable ASPM during NAPI poll | expand

Checks

Context Check Description
netdev/series_format warning Target tree name not specified in the subject
netdev/tree_selection success Guessed tree name to be net-next
netdev/fixes_present success Fixes tag not required for -next series
netdev/header_inline success No static functions without inline keyword in header files
netdev/build_32bit success Errors and warnings before: 0 this patch: 0
netdev/cc_maintainers success CCed 7 of 7 maintainers
netdev/build_clang success Errors and warnings before: 0 this patch: 0
netdev/verify_signedoff success Signed-off-by tag matches author and committer
netdev/deprecated_api success None detected
netdev/check_selftest success No net selftest shell script
netdev/verify_fixes success No Fixes tag
netdev/build_allmodconfig_warn success Errors and warnings before: 0 this patch: 0
netdev/checkpatch success total: 0 errors, 0 warnings, 0 checks, 51 lines checked
netdev/kdoc success Errors and warnings before: 0 this patch: 0
netdev/source_inline success Was 0 now: 0

Commit Message

Heiner Kallweit Feb. 25, 2023, 9:47 p.m. UTC
Now that  ASPM is disabled during NAPI poll, we can remove all ASPM
restrictions. This allows for higher power savings if the network
isn't fully loaded.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
---
 drivers/net/ethernet/realtek/r8169_main.c | 27 +----------------------
 1 file changed, 1 insertion(+), 26 deletions(-)

Comments

Bjorn Helgaas March 10, 2023, 9:19 p.m. UTC | #1
On Sat, Feb 25, 2023 at 10:47:32PM +0100, Heiner Kallweit wrote:
> Now that  ASPM is disabled during NAPI poll, we can remove all ASPM
> restrictions. This allows for higher power savings if the network
> isn't fully loaded.
> 
> Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
> ---
>  drivers/net/ethernet/realtek/r8169_main.c | 27 +----------------------
>  1 file changed, 1 insertion(+), 26 deletions(-)
> 
> diff --git a/drivers/net/ethernet/realtek/r8169_main.c b/drivers/net/ethernet/realtek/r8169_main.c
> index 2897b9bf2..6563e4c6a 100644
> --- a/drivers/net/ethernet/realtek/r8169_main.c
> +++ b/drivers/net/ethernet/realtek/r8169_main.c
> @@ -620,7 +620,6 @@ struct rtl8169_private {
>  	int cfg9346_usage_count;
>  
>  	unsigned supports_gmii:1;
> -	unsigned aspm_manageable:1;
>  	dma_addr_t counters_phys_addr;
>  	struct rtl8169_counters *counters;
>  	struct rtl8169_tc_offsets tc_offset;
> @@ -2744,8 +2743,7 @@ static void rtl_hw_aspm_clkreq_enable(struct rtl8169_private *tp, bool enable)
>  	if (tp->mac_version < RTL_GIGA_MAC_VER_32)
>  		return;
>  
> -	/* Don't enable ASPM in the chip if OS can't control ASPM */
> -	if (enable && tp->aspm_manageable) {
> +	if (enable) {
>  		rtl_mod_config5(tp, 0, ASPM_en);
>  		rtl_mod_config2(tp, 0, ClkReqEn);
>  
> @@ -5221,16 +5219,6 @@ static void rtl_init_mac_address(struct rtl8169_private *tp)
>  	rtl_rar_set(tp, mac_addr);
>  }
>  
> -/* register is set if system vendor successfully tested ASPM 1.2 */
> -static bool rtl_aspm_is_safe(struct rtl8169_private *tp)
> -{
> -	if (tp->mac_version >= RTL_GIGA_MAC_VER_61 &&
> -	    r8168_mac_ocp_read(tp, 0xc0b2) & 0xf)
> -		return true;
> -
> -	return false;
> -}
> -
>  static int rtl_init_one(struct pci_dev *pdev, const struct pci_device_id *ent)
>  {
>  	struct rtl8169_private *tp;
> @@ -5302,19 +5290,6 @@ static int rtl_init_one(struct pci_dev *pdev, const struct pci_device_id *ent)
>  
>  	tp->mac_version = chipset;
>  
> -	/* Disable ASPM L1 as that cause random device stop working
> -	 * problems as well as full system hangs for some PCIe devices users.
> -	 * Chips from RTL8168h partially have issues with L1.2, but seem
> -	 * to work fine with L1 and L1.1.
> -	 */
> -	if (rtl_aspm_is_safe(tp))
> -		rc = 0;
> -	else if (tp->mac_version >= RTL_GIGA_MAC_VER_46)
> -		rc = pci_disable_link_state(pdev, PCIE_LINK_STATE_L1_2);
> -	else
> -		rc = pci_disable_link_state(pdev, PCIE_LINK_STATE_L1);
> -	tp->aspm_manageable = !rc;

This is beautiful.  But since this series still enables/disables ASPM
using the chip-specific knobs, I have to ask whether this is all safe
with respect to simultaneous arbitrary ASPM enable/disable via the
sysfs knobs.  For example, it should be safe to run these loops
indefinitely while the NIC is operating and doing NAPI polls:

  DEV=/sys/bus/pci/devices/...
  while /bin/true; do
    echo 1 > $DEV/link/l1_2_aspm
    echo 0 > $DEV/link/l1_2_aspm
  done
  while /bin/true; do
    echo 1 > $DEV/link/l1_1_aspm
    echo 0 > $DEV/link/l1_1_aspm
  done
  while /bin/true; do
    echo 1 > $DEV/link/l1_aspm
    echo 0 > $DEV/link/l1_aspm
  done

Bjorn
Heiner Kallweit March 10, 2023, 9:41 p.m. UTC | #2
On 10.03.2023 22:19, Bjorn Helgaas wrote:
> On Sat, Feb 25, 2023 at 10:47:32PM +0100, Heiner Kallweit wrote:
>> Now that  ASPM is disabled during NAPI poll, we can remove all ASPM
>> restrictions. This allows for higher power savings if the network
>> isn't fully loaded.
>>
>> Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
>> ---
>>  drivers/net/ethernet/realtek/r8169_main.c | 27 +----------------------
>>  1 file changed, 1 insertion(+), 26 deletions(-)
>>
>> diff --git a/drivers/net/ethernet/realtek/r8169_main.c b/drivers/net/ethernet/realtek/r8169_main.c
>> index 2897b9bf2..6563e4c6a 100644
>> --- a/drivers/net/ethernet/realtek/r8169_main.c
>> +++ b/drivers/net/ethernet/realtek/r8169_main.c
>> @@ -620,7 +620,6 @@ struct rtl8169_private {
>>  	int cfg9346_usage_count;
>>  
>>  	unsigned supports_gmii:1;
>> -	unsigned aspm_manageable:1;
>>  	dma_addr_t counters_phys_addr;
>>  	struct rtl8169_counters *counters;
>>  	struct rtl8169_tc_offsets tc_offset;
>> @@ -2744,8 +2743,7 @@ static void rtl_hw_aspm_clkreq_enable(struct rtl8169_private *tp, bool enable)
>>  	if (tp->mac_version < RTL_GIGA_MAC_VER_32)
>>  		return;
>>  
>> -	/* Don't enable ASPM in the chip if OS can't control ASPM */
>> -	if (enable && tp->aspm_manageable) {
>> +	if (enable) {
>>  		rtl_mod_config5(tp, 0, ASPM_en);
>>  		rtl_mod_config2(tp, 0, ClkReqEn);
>>  
>> @@ -5221,16 +5219,6 @@ static void rtl_init_mac_address(struct rtl8169_private *tp)
>>  	rtl_rar_set(tp, mac_addr);
>>  }
>>  
>> -/* register is set if system vendor successfully tested ASPM 1.2 */
>> -static bool rtl_aspm_is_safe(struct rtl8169_private *tp)
>> -{
>> -	if (tp->mac_version >= RTL_GIGA_MAC_VER_61 &&
>> -	    r8168_mac_ocp_read(tp, 0xc0b2) & 0xf)
>> -		return true;
>> -
>> -	return false;
>> -}
>> -
>>  static int rtl_init_one(struct pci_dev *pdev, const struct pci_device_id *ent)
>>  {
>>  	struct rtl8169_private *tp;
>> @@ -5302,19 +5290,6 @@ static int rtl_init_one(struct pci_dev *pdev, const struct pci_device_id *ent)
>>  
>>  	tp->mac_version = chipset;
>>  
>> -	/* Disable ASPM L1 as that cause random device stop working
>> -	 * problems as well as full system hangs for some PCIe devices users.
>> -	 * Chips from RTL8168h partially have issues with L1.2, but seem
>> -	 * to work fine with L1 and L1.1.
>> -	 */
>> -	if (rtl_aspm_is_safe(tp))
>> -		rc = 0;
>> -	else if (tp->mac_version >= RTL_GIGA_MAC_VER_46)
>> -		rc = pci_disable_link_state(pdev, PCIE_LINK_STATE_L1_2);
>> -	else
>> -		rc = pci_disable_link_state(pdev, PCIE_LINK_STATE_L1);
>> -	tp->aspm_manageable = !rc;
> 
> This is beautiful.  But since this series still enables/disables ASPM
> using the chip-specific knobs, I have to ask whether this is all safe
> with respect to simultaneous arbitrary ASPM enable/disable via the
> sysfs knobs.  For example, it should be safe to run these loops
> indefinitely while the NIC is operating and doing NAPI polls:
> 
Good question, but: Realtek doesn't provide any chip data sheets,
therefore I can't say what the chip-specific knobs actually do.

>   DEV=/sys/bus/pci/devices/...
>   while /bin/true; do
>     echo 1 > $DEV/link/l1_2_aspm
>     echo 0 > $DEV/link/l1_2_aspm
>   done
>   while /bin/true; do
>     echo 1 > $DEV/link/l1_1_aspm
>     echo 0 > $DEV/link/l1_1_aspm
>   done
>   while /bin/true; do
>     echo 1 > $DEV/link/l1_aspm
>     echo 0 > $DEV/link/l1_aspm
>   done
> 
> Bjorn
diff mbox series

Patch

diff --git a/drivers/net/ethernet/realtek/r8169_main.c b/drivers/net/ethernet/realtek/r8169_main.c
index 2897b9bf2..6563e4c6a 100644
--- a/drivers/net/ethernet/realtek/r8169_main.c
+++ b/drivers/net/ethernet/realtek/r8169_main.c
@@ -620,7 +620,6 @@  struct rtl8169_private {
 	int cfg9346_usage_count;
 
 	unsigned supports_gmii:1;
-	unsigned aspm_manageable:1;
 	dma_addr_t counters_phys_addr;
 	struct rtl8169_counters *counters;
 	struct rtl8169_tc_offsets tc_offset;
@@ -2744,8 +2743,7 @@  static void rtl_hw_aspm_clkreq_enable(struct rtl8169_private *tp, bool enable)
 	if (tp->mac_version < RTL_GIGA_MAC_VER_32)
 		return;
 
-	/* Don't enable ASPM in the chip if OS can't control ASPM */
-	if (enable && tp->aspm_manageable) {
+	if (enable) {
 		rtl_mod_config5(tp, 0, ASPM_en);
 		rtl_mod_config2(tp, 0, ClkReqEn);
 
@@ -5221,16 +5219,6 @@  static void rtl_init_mac_address(struct rtl8169_private *tp)
 	rtl_rar_set(tp, mac_addr);
 }
 
-/* register is set if system vendor successfully tested ASPM 1.2 */
-static bool rtl_aspm_is_safe(struct rtl8169_private *tp)
-{
-	if (tp->mac_version >= RTL_GIGA_MAC_VER_61 &&
-	    r8168_mac_ocp_read(tp, 0xc0b2) & 0xf)
-		return true;
-
-	return false;
-}
-
 static int rtl_init_one(struct pci_dev *pdev, const struct pci_device_id *ent)
 {
 	struct rtl8169_private *tp;
@@ -5302,19 +5290,6 @@  static int rtl_init_one(struct pci_dev *pdev, const struct pci_device_id *ent)
 
 	tp->mac_version = chipset;
 
-	/* Disable ASPM L1 as that cause random device stop working
-	 * problems as well as full system hangs for some PCIe devices users.
-	 * Chips from RTL8168h partially have issues with L1.2, but seem
-	 * to work fine with L1 and L1.1.
-	 */
-	if (rtl_aspm_is_safe(tp))
-		rc = 0;
-	else if (tp->mac_version >= RTL_GIGA_MAC_VER_46)
-		rc = pci_disable_link_state(pdev, PCIE_LINK_STATE_L1_2);
-	else
-		rc = pci_disable_link_state(pdev, PCIE_LINK_STATE_L1);
-	tp->aspm_manageable = !rc;
-
 	tp->dash_type = rtl_check_dash(tp);
 
 	tp->cp_cmd = RTL_R16(tp, CPlusCmd) & CPCMD_MASK;