[PATCH V6 4/5] perf/x86/intel/uncore: Fix PMON enumeration with NUMA disabled

[Zide Chen]

When NUMA is disabled on a NUMA-capable platform, UPI and M3UPI PMON
units are not enumerated.

In this case, pcibus_to_node() always returns NUMA_NO_NODE, causing
uncore_device_to_die() to return -1 for all PCI devices. As a result,
the corresponding PMON units are not added to the RB tree.

These PMON units are per-die resources, and their utility when NUMA is
disabled is limited.  The driver does not prohibit their use, and the
enumeration should still work correctly.

Fix this by using uncore_pcibus_to_dieid(), which works regardless of
whether NUMA is enabled.  This requires calling
snbep_pci2phy_map_init() in spr_uncore_pci_init().

Since pci_init() is called before mmio_init(), remove the redundant
snbep_pci2phy_map_init() call from spr_uncore_mmio_init().  If
snbep_pci2phy_map_init() fails, uncore driver should be bailed out,
so the fallback path in spr_uncore_mmio_init() can be removed.

Signed-off-by: Zide Chen <zide.chen@xxxxxxxxx>
---
V6:
- Split from patch v5 3/4.
- Remove the redundant call in spr_uncore_mmio_init().
- Update commit messages.
---
 arch/x86/events/intel/uncore.c       |  1 +
 arch/x86/events/intel/uncore_snbep.c | 26 +++++++++++---------------
 2 files changed, 12 insertions(+), 15 deletions(-)

diff --git a/arch/x86/events/intel/uncore.c b/arch/x86/events/intel/uncore.c
index 786bd51a0d89..e9cc1ba921c5 100644
--- a/arch/x86/events/intel/uncore.c
+++ b/arch/x86/events/intel/uncore.c
@@ -67,6 +67,7 @@ int uncore_die_to_segment(int die)
 	return bus ? pci_domain_nr(bus) : -EINVAL;
 }
 
+/* Note: This API can only be used when NUMA information is available. */
 int uncore_device_to_die(struct pci_dev *dev)
 {
 	int node = pcibus_to_node(dev->bus);
diff --git a/arch/x86/events/intel/uncore_snbep.c b/arch/x86/events/intel/uncore_snbep.c
index 8ee06d4659bb..73da1e88e286 100644
--- a/arch/x86/events/intel/uncore_snbep.c
+++ b/arch/x86/events/intel/uncore_snbep.c
@@ -6415,7 +6415,7 @@ static void spr_update_device_location(int type_id)
 
 	while ((dev = pci_get_device(PCI_VENDOR_ID_INTEL, device, dev)) != NULL) {
 
-		die = uncore_device_to_die(dev);
+		die = uncore_pcibus_to_dieid(dev->bus);
 		if (die < 0)
 			continue;
 
@@ -6439,6 +6439,10 @@ static void spr_update_device_location(int type_id)
 
 int spr_uncore_pci_init(void)
 {
+	int ret = snbep_pci2phy_map_init(0x3250, SKX_CPUNODEID, SKX_GIDNIDMAP, true);
+	if (ret)
+		return ret;
+
 	/*
 	 * The discovery table of UPI on some SPR variant is broken,
 	 * which impacts the detection of both UPI and M3UPI uncore PMON.
@@ -6460,21 +6464,13 @@ int spr_uncore_pci_init(void)
 
 void spr_uncore_mmio_init(void)
 {
-	int ret = snbep_pci2phy_map_init(0x3250, SKX_CPUNODEID, SKX_GIDNIDMAP, true);
+	uncore_mmio_uncores = uncore_get_uncores(UNCORE_ACCESS_MMIO,
+						 UNCORE_SPR_MMIO_EXTRA_UNCORES,
+						 spr_mmio_uncores,
+						 UNCORE_SPR_NUM_UNCORE_TYPES,
+						 spr_uncores);
 
-	if (ret) {
-		uncore_mmio_uncores = uncore_get_uncores(UNCORE_ACCESS_MMIO, 0, NULL,
-							 UNCORE_SPR_NUM_UNCORE_TYPES,
-							 spr_uncores);
-	} else {
-		uncore_mmio_uncores = uncore_get_uncores(UNCORE_ACCESS_MMIO,
-							 UNCORE_SPR_MMIO_EXTRA_UNCORES,
-							 spr_mmio_uncores,
-							 UNCORE_SPR_NUM_UNCORE_TYPES,
-							 spr_uncores);
-
-		spr_uncore_imc_free_running.num_boxes = uncore_type_max_boxes(uncore_mmio_uncores, UNCORE_SPR_IMC) / 2;
-	}
+	spr_uncore_imc_free_running.num_boxes = uncore_type_max_boxes(uncore_mmio_uncores, UNCORE_SPR_IMC) / 2;
 }
 
 /* end of SPR uncore support */
-- 
2.53.0