[PATCH 06/10] drivers/perf: Clean up redundant per-task checks

From: Robin Murphy
Date: Tue Mar 12 2024 - 13:35:56 EST

It turns out that a while back, perf_event_alloc() grew the ability
to properly refuse all per-task and cgroup events on behalf of
uncore/system PMUs using perf_invalid_context, so that's a whole load
more inconsistent boilerplate which can also go from our drivers. This
includes a couple more cases of drivers foolishly checking event->cpu
*after* overriding it with their own (necessarily valid) CPU...

Signed-off-by: Robin Murphy <robin.murphy@xxxxxxx>
---
drivers/perf/alibaba_uncore_drw_pmu.c | 5 -----
drivers/perf/amlogic/meson_ddr_pmu_core.c | 6 ------
drivers/perf/arm-cci.c | 6 ------
drivers/perf/arm-ccn.c | 4 ----
drivers/perf/arm-cmn.c | 5 -----
drivers/perf/arm_cspmu/arm_cspmu.c | 10 ----------
drivers/perf/arm_dmc620_pmu.c | 12 ------------
drivers/perf/arm_dsu_pmu.c | 6 ------
drivers/perf/arm_smmuv3_pmu.c | 5 -----
drivers/perf/cxl_pmu.c | 2 --
drivers/perf/dwc_pcie_pmu.c | 4 ----
drivers/perf/fsl_imx8_ddr_perf.c | 8 --------
drivers/perf/fsl_imx9_ddr_perf.c | 8 --------
drivers/perf/hisilicon/hisi_pcie_pmu.c | 3 ---
drivers/perf/hisilicon/hisi_uncore_pmu.c | 15 ---------------
drivers/perf/hisilicon/hns3_pmu.c | 3 ---
drivers/perf/marvell_cn10k_ddr_pmu.c | 5 -----
drivers/perf/qcom_l2_pmu.c | 6 ------
drivers/perf/qcom_l3_pmu.c | 7 -------
drivers/perf/thunderx2_pmu.c | 10 ----------
drivers/perf/xgene_pmu.c | 9 ---------
21 files changed, 139 deletions(-)

diff --git a/drivers/perf/alibaba_uncore_drw_pmu.c b/drivers/perf/alibaba_uncore_drw_pmu.c
index eadf4118d1ec..42172939721b 100644
--- a/drivers/perf/alibaba_uncore_drw_pmu.c
+++ b/drivers/perf/alibaba_uncore_drw_pmu.c
@@ -535,11 +535,6 @@ static int ali_drw_pmu_event_init(struct perf_event *event)
struct perf_event *sibling;
struct device *dev = drw_pmu->pmu.dev;

- if (event->attach_state & PERF_ATTACH_TASK) {
- dev_err(dev, "Per-task counter cannot allocate!\n");
- return -EOPNOTSUPP;
- }
-
event->cpu = drw_pmu->irq->cpu;

if (event->group_leader != event &&
diff --git a/drivers/perf/amlogic/meson_ddr_pmu_core.c b/drivers/perf/amlogic/meson_ddr_pmu_core.c
index 3bc887cde163..6fcd37b11dd8 100644
--- a/drivers/perf/amlogic/meson_ddr_pmu_core.c
+++ b/drivers/perf/amlogic/meson_ddr_pmu_core.c
@@ -121,12 +121,6 @@ static int meson_ddr_perf_event_init(struct perf_event *event)
u64 config1 = event->attr.config1;
u64 config2 = event->attr.config2;

- if (event->attach_state & PERF_ATTACH_TASK)
- return -EOPNOTSUPP;
-
- if (event->cpu < 0)
- return -EOPNOTSUPP;
-
/* check if the number of parameters is too much */
if (event->attr.config != ALL_CHAN_COUNTER_ID &&
hweight64(config1) + hweight64(config2) > MAX_AXI_PORTS_OF_CHANNEL)
diff --git a/drivers/perf/arm-cci.c b/drivers/perf/arm-cci.c
index cf8fa2474bed..2ccce0e66ada 100644
--- a/drivers/perf/arm-cci.c
+++ b/drivers/perf/arm-cci.c
@@ -1312,10 +1312,6 @@ static int cci_pmu_event_init(struct perf_event *event)
atomic_t *active_events = &cci_pmu->active_events;
int err = 0;

- /* Shared by all CPUs, no meaningful state to sample */
- if (event->attach_state & PERF_ATTACH_TASK)
- return -EOPNOTSUPP;
-
/*
* Following the example set by other "uncore" PMUs, we accept any CPU
* and rewrite its affinity dynamically rather than having perf core
@@ -1325,8 +1321,6 @@ static int cci_pmu_event_init(struct perf_event *event)
* the event being installed into its context, so the PMU's CPU can't
* change under our feet.
*/
- if (event->cpu < 0)
- return -EINVAL;
event->cpu = cci_pmu->cpu;

event->destroy = hw_perf_event_destroy;
diff --git a/drivers/perf/arm-ccn.c b/drivers/perf/arm-ccn.c
index 4114349e62dd..2adb6a1d136f 100644
--- a/drivers/perf/arm-ccn.c
+++ b/drivers/perf/arm-ccn.c
@@ -720,10 +720,6 @@ static int arm_ccn_pmu_event_init(struct perf_event *event)

ccn = pmu_to_arm_ccn(event->pmu);

- if (event->cpu < 0) {
- dev_dbg(ccn->dev, "Can't provide per-task data!\n");
- return -EOPNOTSUPP;
- }
/*
* Many perf core operations (eg. events rotation) operate on a
* single CPU context. This is obvious for CPU PMUs, where one
diff --git a/drivers/perf/arm-cmn.c b/drivers/perf/arm-cmn.c
index e1f151f04c9f..26ede1db1f72 100644
--- a/drivers/perf/arm-cmn.c
+++ b/drivers/perf/arm-cmn.c
@@ -1696,12 +1696,7 @@ static int arm_cmn_event_init(struct perf_event *event)
bool bynodeid;
u16 nodeid, eventid;

- if (event->attach_state & PERF_ATTACH_TASK)
- return -EINVAL;
-
event->cpu = cmn->cpu;
- if (event->cpu < 0)
- return -EINVAL;

type = CMN_EVENT_TYPE(event);
/* DTC events (i.e. cycles) already have everything they need */
diff --git a/drivers/perf/arm_cspmu/arm_cspmu.c b/drivers/perf/arm_cspmu/arm_cspmu.c
index c5c7198e6921..b007e1fdd336 100644
--- a/drivers/perf/arm_cspmu/arm_cspmu.c
+++ b/drivers/perf/arm_cspmu/arm_cspmu.c
@@ -676,16 +676,6 @@ static int arm_cspmu_event_init(struct perf_event *event)

cspmu = to_arm_cspmu(event->pmu);

- /*
- * Following other "uncore" PMUs, we do not support sampling mode or
- * attach to a task (per-process mode).
- */
- if (event->cpu < 0 || event->attach_state & PERF_ATTACH_TASK) {
- dev_dbg(cspmu->pmu.dev,
- "Can't support per-task counters\n");
- return -EINVAL;
- }
-
/*
* Make sure the CPU assignment is on one of the CPUs associated with
* this PMU.
diff --git a/drivers/perf/arm_dmc620_pmu.c b/drivers/perf/arm_dmc620_pmu.c
index 47d3a166bccc..98e7c2333cc6 100644
--- a/drivers/perf/arm_dmc620_pmu.c
+++ b/drivers/perf/arm_dmc620_pmu.c
@@ -515,16 +515,6 @@ static int dmc620_pmu_event_init(struct perf_event *event)
struct hw_perf_event *hwc = &event->hw;
struct perf_event *sibling;

- /*
- * DMC 620 PMUs are shared across all cpus and cannot
- * support task bound and sampling events.
- */
- if (event->attach_state & PERF_ATTACH_TASK) {
- dev_dbg(dmc620_pmu->pmu.dev,
- "Can't support per-task counters\n");
- return -EOPNOTSUPP;
- }
-
/*
* Many perf core operations (eg. events rotation) operate on a
* single CPU context. This is obvious for CPU PMUs, where one
@@ -535,8 +525,6 @@ static int dmc620_pmu_event_init(struct perf_event *event)
* processor.
*/
event->cpu = dmc620_pmu->irq->cpu;
- if (event->cpu < 0)
- return -EINVAL;

/*
* We can't atomically disable all HW counters so only one event allowed,
diff --git a/drivers/perf/arm_dsu_pmu.c b/drivers/perf/arm_dsu_pmu.c
index 3424d165795c..740f8c958976 100644
--- a/drivers/perf/arm_dsu_pmu.c
+++ b/drivers/perf/arm_dsu_pmu.c
@@ -544,12 +544,6 @@ static int dsu_pmu_event_init(struct perf_event *event)
{
struct dsu_pmu *dsu_pmu = to_dsu_pmu(event->pmu);

- /* We cannot support task bound events */
- if (event->cpu < 0 || event->attach_state & PERF_ATTACH_TASK) {
- dev_dbg(dsu_pmu->pmu.dev, "Can't support per-task counters\n");
- return -EINVAL;
- }
-
if (!cpumask_test_cpu(event->cpu, &dsu_pmu->associated_cpus)) {
dev_dbg(dsu_pmu->pmu.dev,
"Requested cpu is not associated with the DSU\n");
diff --git a/drivers/perf/arm_smmuv3_pmu.c b/drivers/perf/arm_smmuv3_pmu.c
index 8206ba0c1637..f4e22ff179b9 100644
--- a/drivers/perf/arm_smmuv3_pmu.c
+++ b/drivers/perf/arm_smmuv3_pmu.c
@@ -401,11 +401,6 @@ static int smmu_pmu_event_init(struct perf_event *event)
int group_num_events = 1;
u16 event_id;

- if (event->cpu < 0) {
- dev_dbg(dev, "Per-task mode not supported\n");
- return -EOPNOTSUPP;
- }
-
/* Verify specified event is supported on this PMU */
event_id = get_event(event);
if (event_id < SMMU_PMCG_ARCH_MAX_EVENTS &&
diff --git a/drivers/perf/cxl_pmu.c b/drivers/perf/cxl_pmu.c
index 41afbbd221a9..e78f8db8ef52 100644
--- a/drivers/perf/cxl_pmu.c
+++ b/drivers/perf/cxl_pmu.c
@@ -571,8 +571,6 @@ static int cxl_pmu_event_init(struct perf_event *event)
struct cxl_pmu_info *info = pmu_to_cxl_pmu_info(event->pmu);
int rc;

- if (event->attach_state & PERF_ATTACH_TASK)
- return -EOPNOTSUPP;
/* TODO: Validation of any filter */

/*
diff --git a/drivers/perf/dwc_pcie_pmu.c b/drivers/perf/dwc_pcie_pmu.c
index 638ad527f252..c2c4a7673e58 100644
--- a/drivers/perf/dwc_pcie_pmu.c
+++ b/drivers/perf/dwc_pcie_pmu.c
@@ -366,10 +366,6 @@ static int dwc_pcie_pmu_event_init(struct perf_event *event)
struct perf_event *sibling;
u32 lane;

- /* We cannot support task bound events */
- if (event->cpu < 0 || event->attach_state & PERF_ATTACH_TASK)
- return -EINVAL;
-
if (event->group_leader != event &&
!is_software_event(event->group_leader))
return -EINVAL;
diff --git a/drivers/perf/fsl_imx8_ddr_perf.c b/drivers/perf/fsl_imx8_ddr_perf.c
index 0070f2bd4d88..612216277ea5 100644
--- a/drivers/perf/fsl_imx8_ddr_perf.c
+++ b/drivers/perf/fsl_imx8_ddr_perf.c
@@ -398,14 +398,6 @@ static int ddr_perf_event_init(struct perf_event *event)
struct hw_perf_event *hwc = &event->hw;
struct perf_event *sibling;

- if (event->attach_state & PERF_ATTACH_TASK)
- return -EOPNOTSUPP;
-
- if (event->cpu < 0) {
- dev_warn(pmu->dev, "Can't provide per-task data!\n");
- return -EOPNOTSUPP;
- }
-
/*
* We must NOT create groups containing mixed PMUs, although software
* events are acceptable (for example to create a CCN group
diff --git a/drivers/perf/fsl_imx9_ddr_perf.c b/drivers/perf/fsl_imx9_ddr_perf.c
index 83822abf8031..80b4703bef89 100644
--- a/drivers/perf/fsl_imx9_ddr_perf.c
+++ b/drivers/perf/fsl_imx9_ddr_perf.c
@@ -416,14 +416,6 @@ static int ddr_perf_event_init(struct perf_event *event)
struct hw_perf_event *hwc = &event->hw;
struct perf_event *sibling;

- if (event->attach_state & PERF_ATTACH_TASK)
- return -EOPNOTSUPP;
-
- if (event->cpu < 0) {
- dev_warn(pmu->dev, "Can't provide per-task data!\n");
- return -EOPNOTSUPP;
- }
-
/*
* We must NOT create groups containing mixed PMUs, although software
* events are acceptable (for example to create a CCN group
diff --git a/drivers/perf/hisilicon/hisi_pcie_pmu.c b/drivers/perf/hisilicon/hisi_pcie_pmu.c
index 7579b93dc462..d37c65d40a30 100644
--- a/drivers/perf/hisilicon/hisi_pcie_pmu.c
+++ b/drivers/perf/hisilicon/hisi_pcie_pmu.c
@@ -358,9 +358,6 @@ static int hisi_pcie_pmu_event_init(struct perf_event *event)
else
hwc->event_base = HISI_PCIE_CNT;

- if (event->attach_state & PERF_ATTACH_TASK)
- return -EOPNOTSUPP;
-
if (!hisi_pcie_pmu_valid_filter(event, pcie_pmu))
return -EINVAL;

diff --git a/drivers/perf/hisilicon/hisi_uncore_pmu.c b/drivers/perf/hisilicon/hisi_uncore_pmu.c
index 7718b031f671..5de53e76e42f 100644
--- a/drivers/perf/hisilicon/hisi_uncore_pmu.c
+++ b/drivers/perf/hisilicon/hisi_uncore_pmu.c
@@ -186,21 +186,6 @@ int hisi_uncore_pmu_event_init(struct perf_event *event)
struct hw_perf_event *hwc = &event->hw;
struct hisi_pmu *hisi_pmu;

- /*
- * We do not support sampling as the counters are all
- * shared by all CPU cores in a CPU die(SCCL). Also we
- * do not support attach to a task(per-process mode)
- */
- if (event->attach_state & PERF_ATTACH_TASK)
- return -EOPNOTSUPP;
-
- /*
- * The uncore counters not specific to any CPU, so cannot
- * support per-task
- */
- if (event->cpu < 0)
- return -EINVAL;
-
/*
* Validate if the events in group does not exceed the
* available counters in hardware.
diff --git a/drivers/perf/hisilicon/hns3_pmu.c b/drivers/perf/hisilicon/hns3_pmu.c
index 3d089df22c01..09bf38e56909 100644
--- a/drivers/perf/hisilicon/hns3_pmu.c
+++ b/drivers/perf/hisilicon/hns3_pmu.c
@@ -1236,9 +1236,6 @@ static int hns3_pmu_event_init(struct perf_event *event)
int idx;
int ret;

- if (event->attach_state & PERF_ATTACH_TASK)
- return -EOPNOTSUPP;
-
event->cpu = hns3_pmu->on_cpu;

idx = hns3_pmu_get_event_idx(hns3_pmu);
diff --git a/drivers/perf/marvell_cn10k_ddr_pmu.c b/drivers/perf/marvell_cn10k_ddr_pmu.c
index bb16a193ff36..ebafa39a6b24 100644
--- a/drivers/perf/marvell_cn10k_ddr_pmu.c
+++ b/drivers/perf/marvell_cn10k_ddr_pmu.c
@@ -325,11 +325,6 @@ static int cn10k_ddr_perf_event_init(struct perf_event *event)
struct cn10k_ddr_pmu *pmu = to_cn10k_ddr_pmu(event->pmu);
struct hw_perf_event *hwc = &event->hw;

- if (event->cpu < 0) {
- dev_warn(pmu->dev, "Can't provide per-task data!\n");
- return -EOPNOTSUPP;
- }
-
/* We must NOT create groups containing mixed PMUs */
if (event->group_leader->pmu != event->pmu &&
!is_software_event(event->group_leader))
diff --git a/drivers/perf/qcom_l2_pmu.c b/drivers/perf/qcom_l2_pmu.c
index 3f7837632988..d85f11c9261f 100644
--- a/drivers/perf/qcom_l2_pmu.c
+++ b/drivers/perf/qcom_l2_pmu.c
@@ -442,12 +442,6 @@ static int l2_cache_event_init(struct perf_event *event)
struct perf_event *sibling;
struct l2cache_pmu *l2cache_pmu = to_l2cache_pmu(event->pmu);

- if (event->cpu < 0) {
- dev_dbg_ratelimited(&l2cache_pmu->pdev->dev,
- "Per-task mode not supported\n");
- return -EOPNOTSUPP;
- }
-
if (((L2_EVT_GROUP(event->attr.config) > L2_EVT_GROUP_MAX) ||
((event->attr.config & ~L2_EVT_MASK) != 0)) &&
(event->attr.config != L2CYCLE_CTR_RAW_CODE)) {
diff --git a/drivers/perf/qcom_l3_pmu.c b/drivers/perf/qcom_l3_pmu.c
index 54fde33802f4..733067fa68e5 100644
--- a/drivers/perf/qcom_l3_pmu.c
+++ b/drivers/perf/qcom_l3_pmu.c
@@ -480,13 +480,6 @@ static int qcom_l3_cache__event_init(struct perf_event *event)
struct l3cache_pmu *l3pmu = to_l3cache_pmu(event->pmu);
struct hw_perf_event *hwc = &event->hw;

- /*
- * Task mode not available, we run the counters as socket counters,
- * not attributable to any CPU and therefore cannot attribute per-task.
- */
- if (event->cpu < 0)
- return -EINVAL;
-
/* Validate the group */
if (!qcom_l3_cache__validate_event_group(event))
return -EINVAL;
diff --git a/drivers/perf/thunderx2_pmu.c b/drivers/perf/thunderx2_pmu.c
index 06b589799536..d9da3070f27c 100644
--- a/drivers/perf/thunderx2_pmu.c
+++ b/drivers/perf/thunderx2_pmu.c
@@ -574,16 +574,6 @@ static int tx2_uncore_event_init(struct perf_event *event)
struct hw_perf_event *hwc = &event->hw;
struct tx2_uncore_pmu *tx2_pmu;

- /*
- * SOC PMU counters are shared across all cores.
- * Therefore, it does not support per-process mode.
- */
- if (event->attach_state & PERF_ATTACH_TASK)
- return -EINVAL;
-
- if (event->cpu < 0)
- return -EINVAL;
-
tx2_pmu = pmu_to_tx2_pmu(event->pmu);
if (tx2_pmu->cpu >= nr_cpu_ids)
return -EINVAL;
diff --git a/drivers/perf/xgene_pmu.c b/drivers/perf/xgene_pmu.c
index 7f753b8f4e93..b2d855866354 100644
--- a/drivers/perf/xgene_pmu.c
+++ b/drivers/perf/xgene_pmu.c
@@ -888,15 +888,6 @@ static int xgene_perf_event_init(struct perf_event *event)
struct hw_perf_event *hw = &event->hw;
struct perf_event *sibling;

- /*
- * SOC PMU counters are shared across all cores.
- * Therefore, it does not support per-process mode.
- */
- if (event->attach_state & PERF_ATTACH_TASK)
- return -EINVAL;
-
- if (event->cpu < 0)
- return -EINVAL;
/*
* Many perf core operations (eg. events rotation) operate on a
* single CPU context. This is obvious for CPU PMUs, where one
--
2.39.2.101.g768bb238c484.dirty