Commit 18973367 authored by Zide Chen's avatar Zide Chen Committed by Peter Zijlstra
Browse files

perf/x86/intel/uncore: Remove has_generic_discovery_table() 



In the !x86_match_cpu() fallback path, has_generic_discovery_table()
is removed because it does not handle multiple PCI devices.  Instead,
use PCI_ANY_ID in generic_uncore_init[] to probe all PCI devices.

For MSR portals, only probe MSR 0x201e to keep the fallback simple, as
this path is best-effort only.

Signed-off-by: default avatarZide Chen <zide.chen@intel.com>
Signed-off-by: default avatarPeter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: default avatarDapeng Mi <dapeng1.mi@linux.intel.com>
Link: https://patch.msgid.link/20251231224233.113839-4-zide.chen@intel.com
parent e75462f6

arch/x86/events/intel/uncore.c

+3 −0
Original line number Diff line number Diff line
@@ -1835,6 +1835,9 @@ static const struct uncore_plat_init generic_uncore_init __initconst = { 
	.cpu_init = intel_uncore_generic_uncore_cpu_init,

	.pci_init = intel_uncore_generic_uncore_pci_init,

	.mmio_init = intel_uncore_generic_uncore_mmio_init,

	.domain[0].base_is_pci = true,

	.domain[0].discovery_base = PCI_ANY_ID,

	.domain[1].discovery_base = UNCORE_DISCOVERY_MSR,

};



static const struct x86_cpu_id intel_uncore_match[] __initconst = {

arch/x86/events/intel/uncore_discovery.c

+9 −33
Original line number Diff line number Diff line
@@ -12,24 +12,6 @@ 
static struct rb_root discovery_tables = RB_ROOT;

static int num_discovered_types[UNCORE_ACCESS_MAX];



static bool has_generic_discovery_table(void)

{

	struct pci_dev *dev;

	int dvsec;



	dev = pci_get_device(PCI_VENDOR_ID_INTEL, UNCORE_DISCOVERY_TABLE_DEVICE, NULL);

	if (!dev)

		return false;



	/* A discovery table device has the unique capability ID. */

	dvsec = pci_find_next_ext_capability(dev, 0, UNCORE_EXT_CAP_ID_DISCOVERY);

	pci_dev_put(dev);

	if (dvsec)

		return true;



	return false;

}



static int logical_die_id;



static int get_device_die_id(struct pci_dev *dev)
@@ -358,12 +340,7 @@ static bool uncore_discovery_pci(struct uncore_discovery_domain *domain) 
	struct pci_dev *dev = NULL;

	bool parsed = false;



	if (domain->discovery_base)

	device = domain->discovery_base;

	else if (has_generic_discovery_table())

		device = UNCORE_DISCOVERY_TABLE_DEVICE;

	else

		device = PCI_ANY_ID;



	/*

	 * Start a new search and iterates through the list of
@@ -406,7 +383,7 @@ static bool uncore_discovery_msr(struct uncore_discovery_domain *domain) 
{

	unsigned long *die_mask;

	bool parsed = false;

	int cpu, die, msr;

	int cpu, die;

	u64 base;



	die_mask = kcalloc(BITS_TO_LONGS(uncore_max_dies()),
@@ -414,16 +391,13 @@ static bool uncore_discovery_msr(struct uncore_discovery_domain *domain) 
	if (!die_mask)

		return false;



	msr = domain->discovery_base ?

	      domain->discovery_base : UNCORE_DISCOVERY_MSR;



	cpus_read_lock();

	for_each_online_cpu(cpu) {

		die = topology_logical_die_id(cpu);

		if (__test_and_set_bit(die, die_mask))

			continue;



		if (rdmsrq_safe_on_cpu(cpu, msr, &base))

		if (rdmsrq_safe_on_cpu(cpu, domain->discovery_base, &base))

			continue;



		if (!base)
@@ -446,11 +420,13 @@ bool uncore_discovery(struct uncore_plat_init *init) 


	for (i = 0; i < UNCORE_DISCOVERY_DOMAINS; i++) {

		domain = &init->domain[i];

		if (domain->discovery_base) {

			if (!domain->base_is_pci)

				ret |= uncore_discovery_msr(domain);

			else

				ret |= uncore_discovery_pci(domain);

		}

	}



	return ret;

}