This patch adds multi-IOMMU support for perf by exposing
an AMD IOMMU PMU for each IOMMU found in the system via:
/sys/device/amd_iommu_x /* where x is the IOMMU index. */
This allows users to specify different events to be programed
onto performance counters of each IOMMU.
Cc: Peter Zijlstra <pet...@infradead.org>
Cc: Borislav Petkov <b...@alien8.de>
Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpa...@amd.com>
---
arch/x86/events/amd/iommu.c | 115 ++++++++++++++++++++++++--------------------
1 file changed, 62 insertions(+), 53 deletions(-)
diff --git a/arch/x86/events/amd/iommu.c b/arch/x86/events/amd/iommu.c
index 35a7b18..0ebadc6 100644
--- a/arch/x86/events/amd/iommu.c
+++ b/arch/x86/events/amd/iommu.c
@@ -35,10 +35,13 @@
#define _GET_PASID_MASK(ev) ((ev->hw.extra_reg.config >> 16) & 0xFFFFULL)
#define _GET_DOMID_MASK(ev) ((ev->hw.extra_reg.config >> 32) & 0xFFFFULL)
-static struct perf_iommu __perf_iommu;
+#define PERF_AMD_IOMMU_NAME_SZ 16
struct perf_iommu {
+ struct list_head list;
struct pmu pmu;
+ int idx;
+ char name[PERF_AMD_IOMMU_NAME_SZ];
u8 max_banks;
u8 max_counters;
u64 cntr_assign_mask;
@@ -46,6 +49,8 @@ struct perf_iommu {
const struct attribute_group *attr_groups[4];
};
+LIST_HEAD(perf_amd_iommu_list);
+
#define format_group attr_groups[0]
#define cpumask_group attr_groups[1]
#define events_group attr_groups[2]
@@ -196,8 +201,7 @@ static int clear_avail_iommu_bnk_cntr(struct perf_iommu
*pi, u8 bank, u8 cntr)
static int perf_iommu_event_init(struct perf_event *event)
{
struct hw_perf_event *hwc = &event->hw;
- struct perf_iommu *pi;
- u64 config, config1;
+ struct perf_iommu *pi = container_of(event->pmu, struct perf_iommu,
pmu);
/* test the event attr type check for PMU enumeration */
if (event->attr.type != event->pmu->type)
@@ -219,27 +223,17 @@ static int perf_iommu_event_init(struct perf_event *event)
if (event->cpu < 0)
return -EINVAL;
- pi = &__perf_iommu;
-
- if (event->pmu != &pi->pmu)
- return -ENOENT;
-
- if (pi) {
- config = event->attr.config;
- config1 = event->attr.config1;
- } else {
- return -EINVAL;
- }
-
/* update the hw_perf_event struct with the iommu config data */
- hwc->config = config;
- hwc->extra_reg.config = config1;
+ hwc->idx = pi->idx;
+ hwc->config = event->attr.config;
+ hwc->extra_reg.config = event->attr.config1;
return 0;
}
static void perf_iommu_enable_event(struct perf_event *ev)
{
+ struct hw_perf_event *hwc = &ev->hw;
u8 csource = _GET_CSOURCE(ev);
u16 devid = _GET_DEVID(ev);
u8 bank = _GET_BANK(ev);
@@ -247,33 +241,34 @@ static void perf_iommu_enable_event(struct perf_event *ev)
u64 reg = 0ULL;
reg = csource;
- amd_iommu_pc_set_reg(0, devid, bank, cntr,
+ amd_iommu_pc_set_reg(hwc->idx, devid, bank, cntr,
IOMMU_PC_COUNTER_SRC_REG, ®);
reg = devid | (_GET_DEVID_MASK(ev) << 32);
if (reg)
reg |= BIT(31);
- amd_iommu_pc_set_reg(0, devid, bank, cntr,
+ amd_iommu_pc_set_reg(hwc->idx, devid, bank, cntr,
IOMMU_PC_DEVID_MATCH_REG, ®);
reg = _GET_PASID(ev) | (_GET_PASID_MASK(ev) << 32);
if (reg)
reg |= BIT(31);
- amd_iommu_pc_set_reg(0, devid, bank, cntr,
+ amd_iommu_pc_set_reg(hwc->idx, devid, bank, cntr,
IOMMU_PC_PASID_MATCH_REG, ®);
reg = _GET_DOMID(ev) | (_GET_DOMID_MASK(ev) << 32);
if (reg)
reg |= BIT(31);
- amd_iommu_pc_set_reg(0, devid, bank, cntr,
+ amd_iommu_pc_set_reg(hwc->idx, devid, bank, cntr,
IOMMU_PC_DOMID_MATCH_REG, ®);
}
static void perf_iommu_disable_event(struct perf_event *event)
{
+ struct hw_perf_event *hwc = &event->hw;
u64 reg = 0ULL;
- amd_iommu_pc_set_reg(0, _GET_DEVID(event), _GET_BANK(event),
+ amd_iommu_pc_set_reg(hwc->idx, _GET_DEVID(event), _GET_BANK(event),
_GET_CNTR(event), IOMMU_PC_COUNTER_SRC_REG, ®);
}
@@ -293,7 +288,7 @@ static void perf_iommu_start(struct perf_event *event, int
flags)
val = local64_read(&hwc->prev_count);
- amd_iommu_pc_set_counter(0, _GET_BANK(event), _GET_CNTR(event), &val);
+ amd_iommu_pc_set_counter(hwc->idx, _GET_BANK(event), _GET_CNTR(event),
&val);
enable:
perf_iommu_enable_event(event);
perf_event_update_userpage(event);
@@ -306,7 +301,7 @@ static void perf_iommu_read(struct perf_event *event)
s64 delta;
struct hw_perf_event *hwc = &event->hw;
- if (amd_iommu_pc_get_counter(0, _GET_BANK(event), _GET_CNTR(event),
&cnt))
+ if (amd_iommu_pc_get_counter(hwc->idx, _GET_BANK(event),
_GET_CNTR(event), &cnt))
return;
/* IOMMU pc counter register is only 48 bits */
@@ -405,13 +400,19 @@ static __init int _init_events_attrs(struct perf_iommu
*pi)
static __init void amd_iommu_pc_exit(void)
{
- if (__perf_iommu.events_group != NULL) {
- kfree(__perf_iommu.events_group);
- __perf_iommu.events_group = NULL;
+ struct perf_iommu *pi, *next;
+
+ list_for_each_entry_safe(pi, next, &perf_amd_iommu_list, list) {
+ list_del(&pi->list);
+
+ kfree(pi->events_group);
+ pi->events_group = NULL;
+
+ kfree(pi);
}
}
-static __init int _init_perf_amd_iommu(struct perf_iommu *pi, char *name)
+static __init int init_one_perf_amd_iommu(struct perf_iommu *pi, int idx)
{
int ret;
@@ -428,53 +429,61 @@ static __init int _init_perf_amd_iommu(struct perf_iommu
*pi, char *name)
if (_init_events_attrs(pi) != 0)
pr_err("Only support raw events.\n");
- pi->max_banks = amd_iommu_pc_get_max_banks(0);
- pi->max_counters = amd_iommu_pc_get_max_counters(0);
+ snprintf(pi->name, PERF_AMD_IOMMU_NAME_SZ, "amd_iommu_%u", idx);
+ pi->idx = idx;
+ pi->max_banks = amd_iommu_pc_get_max_banks(idx);
+ pi->max_counters = amd_iommu_pc_get_max_counters(idx);
if (!pi->max_banks || !pi->max_counters)
return -EINVAL;
/* Init null attributes */
pi->null_group = NULL;
+
+ /* Setting up PMU */
+ pi->pmu.event_init = perf_iommu_event_init,
+ pi->pmu.add = perf_iommu_add,
+ pi->pmu.del = perf_iommu_del,
+ pi->pmu.start = perf_iommu_start,
+ pi->pmu.stop = perf_iommu_stop,
+ pi->pmu.read = perf_iommu_read,
pi->pmu.attr_groups = pi->attr_groups;
- ret = perf_pmu_register(&pi->pmu, name, -1);
+ ret = perf_pmu_register(&pi->pmu, pi->name, -1);
if (ret) {
pr_err("Error initializing AMD IOMMU perf counters.\n");
amd_iommu_pc_exit();
} else {
- pr_info("perf: amd_iommu: Detected. (%d banks, %d
counters/bank)\n",
- amd_iommu_pc_get_max_banks(0),
- amd_iommu_pc_get_max_counters(0));
+ pr_info("Detected %s, w/ %d banks, %d counters/bank\n",
+ pi->name,
+ amd_iommu_pc_get_max_banks(idx),
+ amd_iommu_pc_get_max_counters(idx));
+
+ list_add_tail(&pi->list, &perf_amd_iommu_list);
}
return ret;
}
-static struct perf_iommu __perf_iommu = {
- .pmu = {
- .event_init = perf_iommu_event_init,
- .add = perf_iommu_add,
- .del = perf_iommu_del,
- .start = perf_iommu_start,
- .stop = perf_iommu_stop,
- .read = perf_iommu_read,
- },
- .max_banks = 0x00,
- .max_counters = 0x00,
- .cntr_assign_mask = 0ULL,
- .format_group = NULL,
- .cpumask_group = NULL,
- .events_group = NULL,
- .null_group = NULL,
-};
-
static __init int amd_iommu_pc_init(void)
{
+ int i;
+
/* Make sure the IOMMU PC resource is available */
if (!amd_iommu_pc_supported())
return -ENODEV;
- _init_perf_amd_iommu(&__perf_iommu, "amd_iommu");
+ for (i = 0 ; i < amd_iommu_get_num_iommus(); i++) {
+ int ret;
+ struct perf_iommu *pi;
+
+ pi = kzalloc(sizeof(struct perf_iommu), GFP_KERNEL);
+ if (!pi)
+ return -ENOMEM;
+
+ ret = init_one_perf_amd_iommu(pi, i);
+ if (ret)
+ return ret;
+ }
return 0;
}
--
1.9.1
_______________________________________________
iommu mailing list
iommu@lists.linux-foundation.org
https://lists.linuxfoundation.org/mailman/listinfo/iommu
