Re: [PATCH] [RESEND] perf/x86/intel/uncore: Fix the index of PCU.3 Broadwell CPUs

["Liang, Kan" <kan.liang@linux.intel.com>]

On 7/16/2018 11:07 AM, Masayoshi Mizuma wrote:
> 
> 
> On 07/16/2018 10:29 AM, Liang, Kan wrote:
>>
>>
>> On 7/15/2018 6:34 PM, Ingo Molnar wrote:
>>>
>>> * Masayoshi Mizuma <msys.mizuma@gmail.com> wrote:
>>>
>>>> From: Masayoshi Mizuma <m.mizuma@jp.fujitsu.com>
>>>>
>>>> commit 15a3e845b01c ("perf/x86/intel/uncore: Fix SBOX support for
>>>> Broadwell CPUs") introduced PCU.3 for Broadwell CPU. Unfortunately,
>>>> the driver_data of PCU.3 conflicts to QPI Port 2 filter.
>>>>
>>>>       { /* QPI Port 2 filter  */
>>>>               PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x6f46),
>>>>               .driver_data = UNCORE_PCI_DEV_DATA(UNCORE_EXTRA_PCI_DEV, 2),
>>>>
>>>>       { /* PCU.3 (for Capability registers) */
>>>>               PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x6fc0),
>>>>               .driver_data = UNCORE_PCI_DEV_DATA(UNCORE_EXTRA_PCI_DEV,
>>>>                                                  HSWEP_PCI_PCU_3),
>>>>                                // HSWEP_PCI_PCU_3 == 2
>>>
>>>> --- a/arch/x86/events/intel/uncore_snbep.c
>>>> +++ b/arch/x86/events/intel/uncore_snbep.c
>>>> @@ -1030,6 +1030,7 @@ enum {
>>>>        SNBEP_PCI_QPI_PORT0_FILTER,
>>>>        SNBEP_PCI_QPI_PORT1_FILTER,
>>>>        HSWEP_PCI_PCU_3,
>>>> +    BDX_PCI_PCU_3,
>>>>    };
>>>
>>> So we use a magic '2' enumerator in the 'QPI Port 2 filter', and that overlaps
>>> with HSWEP_PCI_PCU_3, right?
>>>
>>> Shouldn't we clean up all the enumerators and not use magic numbers, and this fix
>>> the conflict?
>>>
>>
>> Yes, it should fix the conflict. I will clean up the code.
> 
> Thanks a lot!
> I would appreciate if you could add CC to me when you post the patch.
> 

Here is the patch.

Masa, could you please give it a try?

Thanks,
Kan

 From 688378a4003ec33156958a52dc822105c18075af Mon Sep 17 00:00:00 2001
From: Kan Liang <kan.liang@linux.intel.com>
Date: Mon, 16 Jul 2018 04:57:51 -0400
Subject: [PATCH] perf/x86/intel/uncore: Fix hardcode index of Broadwell 
extra PCI DEV

Masa reports that a warning message is shown while CPU hot-removing on
Broadwell server.

   WARNING: CPU: 126 PID: 6 at arch/x86/events/intel/uncore.c:988
   uncore_pci_remove+0x10b/0x150
   Call Trace:
    pci_device_remove+0x42/0xd0
    device_release_driver_internal+0x148/0x220
    pci_stop_bus_device+0x76/0xa0
    pci_stop_root_bus+0x44/0x60
    acpi_pci_root_remove+0x1f/0x80
    acpi_bus_trim+0x57/0x90
    acpi_bus_trim+0x2e/0x90
    acpi_device_hotplug+0x2bc/0x4b0
    acpi_hotplug_work_fn+0x1a/0x30
    process_one_work+0x174/0x3a0
    worker_thread+0x4c/0x3d0
    kthread+0xf8/0x130

This bug was introduced in:

   commit 15a3e845b01c ("perf/x86/intel/uncore: Fix SBOX support for
Broadwell CPUs")

The index of "QPI Port 2 filter" was hardcode to 2. The index of
"PCU.3" used enumerator "HSWEP_PCI_PCU_3", which equals to 2 as well.

To fix the conflict, the hardcode index needs to be cleaned up.
Introduce a new enumerator "BDX_PCI_QPI_PORT2_FILTER" for "QPI Port 2
filter" on Broadwell, and increase the UNCORE_EXTRA_PCI_DEV_MAX.
Clean up hardcode index.

Reported-by: Masayoshi Mizuma <m.mizuma@jp.fujitsu.com>
Suggested-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Fixes: 15a3e845b01c ("perf/x86/intel/uncore: Fix SBOX support for
Broadwell CPUs")
---
  arch/x86/events/intel/uncore.h       |  2 +-
  arch/x86/events/intel/uncore_snbep.c | 10 +++++++---
  2 files changed, 8 insertions(+), 4 deletions(-)

diff --git a/arch/x86/events/intel/uncore.h b/arch/x86/events/intel/uncore.h
index c9e1e0b..e17ab88 100644
--- a/arch/x86/events/intel/uncore.h
+++ b/arch/x86/events/intel/uncore.h
@@ -28,7 +28,7 @@
  #define UNCORE_PCI_DEV_TYPE(data)	((data >> 8) & 0xff)
  #define UNCORE_PCI_DEV_IDX(data)	(data & 0xff)
  #define UNCORE_EXTRA_PCI_DEV		0xff
-#define UNCORE_EXTRA_PCI_DEV_MAX	3
+#define UNCORE_EXTRA_PCI_DEV_MAX	4

  #define UNCORE_EVENT_CONSTRAINT(c, n) EVENT_CONSTRAINT(c, n, 0xff)

diff --git a/arch/x86/events/intel/uncore_snbep.c 
b/arch/x86/events/intel/uncore_snbep.c
index 87dc026..51d7c11 100644
--- a/arch/x86/events/intel/uncore_snbep.c
+++ b/arch/x86/events/intel/uncore_snbep.c
@@ -1029,6 +1029,7 @@ void snbep_uncore_cpu_init(void)
  enum {
  	SNBEP_PCI_QPI_PORT0_FILTER,
  	SNBEP_PCI_QPI_PORT1_FILTER,
+	BDX_PCI_QPI_PORT2_FILTER,
  	HSWEP_PCI_PCU_3,
  };

@@ -3286,15 +3287,18 @@ static const struct pci_device_id 
bdx_uncore_pci_ids[] = {
  	},
  	{ /* QPI Port 0 filter  */
  		PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x6f86),
-		.driver_data = UNCORE_PCI_DEV_DATA(UNCORE_EXTRA_PCI_DEV, 0),
+		.driver_data = UNCORE_PCI_DEV_DATA(UNCORE_EXTRA_PCI_DEV,
+						   SNBEP_PCI_QPI_PORT0_FILTER),
  	},
  	{ /* QPI Port 1 filter  */
  		PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x6f96),
-		.driver_data = UNCORE_PCI_DEV_DATA(UNCORE_EXTRA_PCI_DEV, 1),
+		.driver_data = UNCORE_PCI_DEV_DATA(UNCORE_EXTRA_PCI_DEV,
+						   SNBEP_PCI_QPI_PORT1_FILTER),
  	},
  	{ /* QPI Port 2 filter  */
  		PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x6f46),
-		.driver_data = UNCORE_PCI_DEV_DATA(UNCORE_EXTRA_PCI_DEV, 2),
+		.driver_data = UNCORE_PCI_DEV_DATA(UNCORE_EXTRA_PCI_DEV,
+						   BDX_PCI_QPI_PORT2_FILTER),
  	},
  	{ /* PCU.3 (for Capability registers) */
  		PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x6fc0),
-- 
2.4.11