Kernel/linux-next
1
0
Fork 0
mirror of https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git synced 2025-01-15 11:37:47 +00:00
Code Issues Actions Packages Projects Releases Wiki Activity

perf/x86/intel/uncore: Clean up func_id

Browse Source 
The below warning may be triggered on GNR when the PCIE uncore units are
exposed.

WARNING: CPU: 4 PID: 1 at arch/x86/events/intel/uncore.c:1169 uncore_pci_pmu_register+0x158/0x190

The current uncore driver assumes that all the devices in the same PMU
have the exact same devfn. It's true for the previous platforms. But it
doesn't work for the new PCIE uncore units on GNR.

The assumption doesn't make sense. There is no reason to limit the
devices from the same PMU to the same devfn. Also, the current code just
throws the warning, but still registers the device. The WARN_ON_ONCE()
should be removed.

The func_id is used by the later event_init() to check if a event->pmu
has valid devices. For cpu and mmio uncore PMUs, they are always valid.
For pci uncore PMUs, it's set when the PMU is registered. It can be
replaced by the pmu->registered. Clean up the func_id.

Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Tested-by: Eric Hu <eric.hu@intel.com>
Link: https://lkml.kernel.org/r/20250108143017.1793781-1-kan.liang@linux.intel.com
This commit is contained in:
Kan Liang 2025-01-08 06:30:16 -08:00 committed by Peter Zijlstra
parent 0e45818ec1
commit 3f710be02e
3 changed files with 8 additions and 15 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

20
arch/x86/events/intel/uncore.c
View File

@ -745,7 +745,7 @@ static int uncore_pmu_event_init(struct perf_event *event)
pmu = uncore_event_to_pmu(event);
/* no device found for this pmu */
if (pmu->func_id < 0)
if (!pmu->registered)
return -ENOENT;
/* Sampling not supported yet */
@ -992,7 +992,7 @@ static void uncore_types_exit(struct intel_uncore_type **types)
uncore_type_exit(*types);
}
static int __init uncore_type_init(struct intel_uncore_type *type, bool setid)
static int __init uncore_type_init(struct intel_uncore_type *type)
{
struct intel_uncore_pmu *pmus;
size_t size;
@ -1005,7 +1005,6 @@ static int __init uncore_type_init(struct intel_uncore_type *type, bool setid)
size = uncore_max_dies() * sizeof(struct intel_uncore_box *);
for (i = 0; i < type->num_boxes; i++) {
pmus[i].func_id = setid ? i : -1;
pmus[i].pmu_idx = i;
pmus[i].type = type;
pmus[i].boxes = kzalloc(size, GFP_KERNEL);
@ -1055,12 +1054,12 @@ err:
}
static int __init
uncore_types_init(struct intel_uncore_type **types, bool setid)
uncore_types_init(struct intel_uncore_type **types)
{
int ret;
for (; *types; types++) {
ret = uncore_type_init(*types, setid);
ret = uncore_type_init(*types);
if (ret)
return ret;
}
@ -1160,11 +1159,6 @@ static int uncore_pci_pmu_register(struct pci_dev *pdev,
if (!box)
return -ENOMEM;
if (pmu->func_id < 0)
pmu->func_id = pdev->devfn;
else
WARN_ON_ONCE(pmu->func_id != pdev->devfn);
atomic_inc(&box->refcnt);
box->dieid = die;
box->pci_dev = pdev;
@ -1410,7 +1404,7 @@ static int __init uncore_pci_init(void)
goto err;
}
ret = uncore_types_init(uncore_pci_uncores, false);
ret = uncore_types_init(uncore_pci_uncores);
if (ret)
goto errtype;
@ -1678,7 +1672,7 @@ static int __init uncore_cpu_init(void)
{
int ret;
ret = uncore_types_init(uncore_msr_uncores, true);
ret = uncore_types_init(uncore_msr_uncores);
if (ret)
goto err;
@ -1697,7 +1691,7 @@ static int __init uncore_mmio_init(void)
struct intel_uncore_type **types = uncore_mmio_uncores;
int ret;
ret = uncore_types_init(types, true);
ret = uncore_types_init(types);
if (ret)
goto err;

1
arch/x86/events/intel/uncore.h
View File

@ -125,7 +125,6 @@ struct intel_uncore_pmu {
struct pmu pmu;
char name[UNCORE_PMU_NAME_LEN];
int pmu_idx;
int func_id;
bool registered;
atomic_t activeboxes;
cpumask_t cpu_mask;

2
arch/x86/events/intel/uncore_snb.c
View File

@ -910,7 +910,7 @@ static int snb_uncore_imc_event_init(struct perf_event *event)
pmu = uncore_event_to_pmu(event);
/* no device found for this pmu */
if (pmu->func_id < 0)
if (!pmu->registered)
return -ENOENT;
/* Sampling not supported yet */