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perf/x86/intel/uncore: Fix multi-segment problem of perf_event_intel_uncore 

In multi-segment system, uncore devices may belong to buses whose segment
number is other than 0:

  ....
  0000:ff:10.5 System peripheral: Intel Corporation Xeon E5 v3/Core i7 Scratchpad & Semaphore Registers (rev 03)
  ...
  0001:7f:10.5 System peripheral: Intel Corporation Xeon E5 v3/Core i7 Scratchpad & Semaphore Registers (rev 03)
  ...
  0001:bf:10.5 System peripheral: Intel Corporation Xeon E5 v3/Core i7 Scratchpad & Semaphore Registers (rev 03)
  ...
  0001:ff:10.5 System peripheral: Intel Corporation Xeon E5 v3/Core i7 Scratchpad & Semaphore Registers (rev 03
  ...

In that case, relation of bus number and physical id may be broken
because "uncore_pcibus_to_physid" doesn't take account of PCI segment.
For example, bus 0000:ff and 0001:ff uses the same entry of
"uncore_pcibus_to_physid" array.

This patch fixes this problem by introducing the segment-aware pci2phy_map instead.

Signed-off-by: Taku Izumi <izumi.taku@jp.fujitsu.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: acme@kernel.org
Cc: hpa@zytor.com
Link: http://lkml.kernel.org/r/1443096621-4119-1-git-send-email-izumi.taku@jp.fujitsu.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
hifive-unleashed-5.1
Taku Izumi 2015-09-24 21:10:21 +09:00 committed by Ingo Molnar
parent 7ce1346a68
commit 712df65ccb
4 changed files with 105 additions and 14 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

61
arch/x86/kernel/cpu/perf_event_intel_uncore.c
View File

@ -7,7 +7,8 @@ struct intel_uncore_type **uncore_pci_uncores = empty_uncore;
static bool pcidrv_registered;
struct pci_driver *uncore_pci_driver;
/* pci bus to socket mapping */
int uncore_pcibus_to_physid[256] = { [0 ... 255] = -1, };
DEFINE_RAW_SPINLOCK(pci2phy_map_lock);
struct list_head pci2phy_map_head = LIST_HEAD_INIT(pci2phy_map_head);
struct pci_dev *uncore_extra_pci_dev[UNCORE_SOCKET_MAX][UNCORE_EXTRA_PCI_DEV_MAX];
static DEFINE_RAW_SPINLOCK(uncore_box_lock);
@ -20,6 +21,59 @@ static struct event_constraint uncore_constraint_fixed =
struct event_constraint uncore_constraint_empty =
EVENT_CONSTRAINT(0, 0, 0);
int uncore_pcibus_to_physid(struct pci_bus *bus)
{
struct pci2phy_map *map;
int phys_id = -1;
raw_spin_lock(&pci2phy_map_lock);
list_for_each_entry(map, &pci2phy_map_head, list) {
if (map->segment == pci_domain_nr(bus)) {
phys_id = map->pbus_to_physid[bus->number];
break;
}
}
raw_spin_unlock(&pci2phy_map_lock);
return phys_id;
}
struct pci2phy_map *__find_pci2phy_map(int segment)
{
struct pci2phy_map *map, *alloc = NULL;
int i;
lockdep_assert_held(&pci2phy_map_lock);
lookup:
list_for_each_entry(map, &pci2phy_map_head, list) {
if (map->segment == segment)
goto end;
}
if (!alloc) {
raw_spin_unlock(&pci2phy_map_lock);
alloc = kmalloc(sizeof(struct pci2phy_map), GFP_KERNEL);
raw_spin_lock(&pci2phy_map_lock);
if (!alloc)
return NULL;
goto lookup;
}
map = alloc;
alloc = NULL;
map->segment = segment;
for (i = 0; i < 256; i++)
map->pbus_to_physid[i] = -1;
list_add_tail(&map->list, &pci2phy_map_head);
end:
kfree(alloc);
return map;
}
ssize_t uncore_event_show(struct kobject *kobj,
struct kobj_attribute *attr, char *buf)
{
@ -809,7 +863,7 @@ static int uncore_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id
int phys_id;
bool first_box = false;
phys_id = uncore_pcibus_to_physid[pdev->bus->number];
phys_id = uncore_pcibus_to_physid(pdev->bus);
if (phys_id < 0)
return -ENODEV;
@ -856,9 +910,10 @@ static void uncore_pci_remove(struct pci_dev *pdev)
{
struct intel_uncore_box *box = pci_get_drvdata(pdev);
struct intel_uncore_pmu *pmu;
int i, cpu, phys_id = uncore_pcibus_to_physid[pdev->bus->number];
int i, cpu, phys_id;
bool last_box = false;
phys_id = uncore_pcibus_to_physid(pdev->bus);
box = pci_get_drvdata(pdev);
if (!box) {
for (i = 0; i < UNCORE_EXTRA_PCI_DEV_MAX; i++) {

12
arch/x86/kernel/cpu/perf_event_intel_uncore.h
View File

@ -117,6 +117,15 @@ struct uncore_event_desc {
const char *config;
};
struct pci2phy_map {
struct list_head list;
int segment;
int pbus_to_physid[256];
};
int uncore_pcibus_to_physid(struct pci_bus *bus);
struct pci2phy_map *__find_pci2phy_map(int segment);
ssize_t uncore_event_show(struct kobject *kobj,
struct kobj_attribute *attr, char *buf);
@ -317,7 +326,8 @@ u64 uncore_shared_reg_config(struct intel_uncore_box *box, int idx);
extern struct intel_uncore_type **uncore_msr_uncores;
extern struct intel_uncore_type **uncore_pci_uncores;
extern struct pci_driver *uncore_pci_driver;
extern int uncore_pcibus_to_physid[256];
extern raw_spinlock_t pci2phy_map_lock;
extern struct list_head pci2phy_map_head;
extern struct pci_dev *uncore_extra_pci_dev[UNCORE_SOCKET_MAX][UNCORE_EXTRA_PCI_DEV_MAX];
extern struct event_constraint uncore_constraint_empty;

14
arch/x86/kernel/cpu/perf_event_intel_uncore_snb.c
View File

@ -420,15 +420,25 @@ static void snb_uncore_imc_event_del(struct perf_event *event, int flags)
static int snb_pci2phy_map_init(int devid)
{
struct pci_dev *dev = NULL;
int bus;
struct pci2phy_map *map;
int bus, segment;
dev = pci_get_device(PCI_VENDOR_ID_INTEL, devid, dev);
if (!dev)
return -ENOTTY;
bus = dev->bus->number;
segment = pci_domain_nr(dev->bus);
uncore_pcibus_to_physid[bus] = 0;
raw_spin_lock(&pci2phy_map_lock);
map = __find_pci2phy_map(segment);
if (!map) {
raw_spin_unlock(&pci2phy_map_lock);
pci_dev_put(dev);
return -ENOMEM;
}
map->pbus_to_physid[bus] = 0;
raw_spin_unlock(&pci2phy_map_lock);
pci_dev_put(dev);

32
arch/x86/kernel/cpu/perf_event_intel_uncore_snbep.c
View File

@ -1087,7 +1087,8 @@ static struct pci_driver snbep_uncore_pci_driver = {
static int snbep_pci2phy_map_init(int devid)
{
struct pci_dev *ubox_dev = NULL;
int i, bus, nodeid;
int i, bus, nodeid, segment;
struct pci2phy_map *map;
int err = 0;
u32 config = 0;
@ -1106,16 +1107,27 @@ static int snbep_pci2phy_map_init(int devid)
err = pci_read_config_dword(ubox_dev, 0x54, &config);
if (err)
break;
segment = pci_domain_nr(ubox_dev->bus);
raw_spin_lock(&pci2phy_map_lock);
map = __find_pci2phy_map(segment);
if (!map) {
raw_spin_unlock(&pci2phy_map_lock);
err = -ENOMEM;
break;
}
/*
* every three bits in the Node ID mapping register maps
* to a particular node.
*/
for (i = 0; i < 8; i++) {
if (nodeid == ((config >> (3 * i)) & 0x7)) {
uncore_pcibus_to_physid[bus] = i;
map->pbus_to_physid[bus] = i;
break;
}
}
raw_spin_unlock(&pci2phy_map_lock);
}
if (!err) {
@ -1123,13 +1135,17 @@ static int snbep_pci2phy_map_init(int devid)
* For PCI bus with no UBOX device, find the next bus
* that has UBOX device and use its mapping.
*/
i = -1;
for (bus = 255; bus >= 0; bus--) {
if (uncore_pcibus_to_physid[bus] >= 0)
i = uncore_pcibus_to_physid[bus];
else
uncore_pcibus_to_physid[bus] = i;
raw_spin_lock(&pci2phy_map_lock);
list_for_each_entry(map, &pci2phy_map_head, list) {
i = -1;
for (bus = 255; bus >= 0; bus--) {
if (map->pbus_to_physid[bus] >= 0)
i = map->pbus_to_physid[bus];
else
map->pbus_to_physid[bus] = i;
}
}
raw_spin_unlock(&pci2phy_map_lock);
}
pci_dev_put(ubox_dev);