From 05e59e5fb0064c97a1c10921ecd549f2d4a58565 Mon Sep 17 00:00:00 2001
From: hc <hc@nodka.com>
Date: Wed, 09 Oct 2024 06:14:40 +0000
Subject: [PATCH] add REDIRECT
---
kernel/arch/powerpc/perf/hv-gpci.c | 122 ++++++++++++++++++++++++++++++++--------
1 files changed, 98 insertions(+), 24 deletions(-)
diff --git a/kernel/arch/powerpc/perf/hv-gpci.c b/kernel/arch/powerpc/perf/hv-gpci.c
index 160b86d..28b770b 100644
--- a/kernel/arch/powerpc/perf/hv-gpci.c
+++ b/kernel/arch/powerpc/perf/hv-gpci.c
@@ -1,14 +1,10 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
/*
* Hypervisor supplied "gpci" ("get performance counter info") performance
* counter support
*
* Author: Cody P Schafer <cody@linux.vnet.ibm.com>
* Copyright 2014 IBM Corporation.
- *
- * This program is free software; you can redistribute it and/or
- * modify it under the terms of the GNU General Public License
- * as published by the Free Software Foundation; either version
- * 2 of the License, or (at your option) any later version.
*/
#define pr_fmt(fmt) "hv-gpci: " fmt
@@ -52,6 +48,8 @@
/* u32, byte offset */
EVENT_DEFINE_RANGE_FORMAT(offset, config1, 32, 63);
+static cpumask_t hv_gpci_cpumask;
+
static struct attribute *format_attrs[] = {
&format_attr_request.attr,
&format_attr_starting_index.attr,
@@ -74,7 +72,7 @@
static struct attribute_group event_group = {
.name = "events",
- .attrs = hv_gpci_event_attrs,
+ /* .attrs is set in init */
};
#define HV_CAPS_ATTR(_name, _format) \
@@ -98,7 +96,15 @@
return sprintf(page, "0x%x\n", COUNTER_INFO_VERSION_CURRENT);
}
+static ssize_t cpumask_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ return cpumap_print_to_pagebuf(true, buf, &hv_gpci_cpumask);
+}
+
static DEVICE_ATTR_RO(kernel_version);
+static DEVICE_ATTR_RO(cpumask);
+
HV_CAPS_ATTR(version, "0x%x\n");
HV_CAPS_ATTR(ga, "%d\n");
HV_CAPS_ATTR(expanded, "%d\n");
@@ -115,6 +121,15 @@
NULL,
};
+static struct attribute *cpumask_attrs[] = {
+ &dev_attr_cpumask.attr,
+ NULL,
+};
+
+static struct attribute_group cpumask_attr_group = {
+ .attrs = cpumask_attrs,
+};
+
static struct attribute_group interface_group = {
.name = "interface",
.attrs = interface_attrs,
@@ -124,19 +139,11 @@
&format_group,
&event_group,
&interface_group,
+ &cpumask_attr_group,
NULL,
};
-#define HGPCI_REQ_BUFFER_SIZE 4096
-#define HGPCI_MAX_DATA_BYTES \
- (HGPCI_REQ_BUFFER_SIZE - sizeof(struct hv_get_perf_counter_info_params))
-
static DEFINE_PER_CPU(char, hv_gpci_reqb[HGPCI_REQ_BUFFER_SIZE]) __aligned(sizeof(uint64_t));
-
-struct hv_gpci_request_buffer {
- struct hv_get_perf_counter_info_params params;
- uint8_t bytes[HGPCI_MAX_DATA_BYTES];
-} __packed;
static unsigned long single_gpci_request(u32 req, u32 starting_index,
u16 secondary_index, u8 version_in, u32 offset, u8 length,
@@ -232,15 +239,6 @@
return -EINVAL;
}
- /* unsupported modes and filters */
- if (event->attr.exclude_user ||
- event->attr.exclude_kernel ||
- event->attr.exclude_hv ||
- event->attr.exclude_idle ||
- event->attr.exclude_host ||
- event->attr.exclude_guest)
- return -EINVAL;
-
/* no branch sampling */
if (has_branch_stack(event))
return -EOPNOTSUPP;
@@ -285,13 +283,54 @@
.start = h_gpci_event_start,
.stop = h_gpci_event_stop,
.read = h_gpci_event_update,
+ .capabilities = PERF_PMU_CAP_NO_EXCLUDE,
};
+
+static int ppc_hv_gpci_cpu_online(unsigned int cpu)
+{
+ if (cpumask_empty(&hv_gpci_cpumask))
+ cpumask_set_cpu(cpu, &hv_gpci_cpumask);
+
+ return 0;
+}
+
+static int ppc_hv_gpci_cpu_offline(unsigned int cpu)
+{
+ int target;
+
+ /* Check if exiting cpu is used for collecting gpci events */
+ if (!cpumask_test_and_clear_cpu(cpu, &hv_gpci_cpumask))
+ return 0;
+
+ /* Find a new cpu to collect gpci events */
+ target = cpumask_last(cpu_active_mask);
+
+ if (target < 0 || target >= nr_cpu_ids) {
+ pr_err("hv_gpci: CPU hotplug init failed\n");
+ return -1;
+ }
+
+ /* Migrate gpci events to the new target */
+ cpumask_set_cpu(target, &hv_gpci_cpumask);
+ perf_pmu_migrate_context(&h_gpci_pmu, cpu, target);
+
+ return 0;
+}
+
+static int hv_gpci_cpu_hotplug_init(void)
+{
+ return cpuhp_setup_state(CPUHP_AP_PERF_POWERPC_HV_GPCI_ONLINE,
+ "perf/powerpc/hv_gcpi:online",
+ ppc_hv_gpci_cpu_online,
+ ppc_hv_gpci_cpu_offline);
+}
static int hv_gpci_init(void)
{
int r;
unsigned long hret;
struct hv_perf_caps caps;
+ struct hv_gpci_request_buffer *arg;
hv_gpci_assert_offsets_correct();
@@ -307,9 +346,44 @@
return -ENODEV;
}
+ /* init cpuhotplug */
+ r = hv_gpci_cpu_hotplug_init();
+ if (r)
+ return r;
+
/* sampling not supported */
h_gpci_pmu.capabilities |= PERF_PMU_CAP_NO_INTERRUPT;
+ arg = (void *)get_cpu_var(hv_gpci_reqb);
+ memset(arg, 0, HGPCI_REQ_BUFFER_SIZE);
+
+ /*
+ * hcall H_GET_PERF_COUNTER_INFO populates the output
+ * counter_info_version value based on the system hypervisor.
+ * Pass the counter request 0x10 corresponds to request type
+ * 'Dispatch_timebase_by_processor', to get the supported
+ * counter_info_version.
+ */
+ arg->params.counter_request = cpu_to_be32(0x10);
+
+ r = plpar_hcall_norets(H_GET_PERF_COUNTER_INFO,
+ virt_to_phys(arg), HGPCI_REQ_BUFFER_SIZE);
+ if (r) {
+ pr_devel("hcall failed, can't get supported counter_info_version: 0x%x\n", r);
+ arg->params.counter_info_version_out = 0x8;
+ }
+
+ /*
+ * Use counter_info_version_out value to assign
+ * required hv-gpci event list.
+ */
+ if (arg->params.counter_info_version_out >= 0x8)
+ event_group.attrs = hv_gpci_event_attrs;
+ else
+ event_group.attrs = hv_gpci_event_attrs_v6;
+
+ put_cpu_var(hv_gpci_reqb);
+
r = perf_pmu_register(&h_gpci_pmu, h_gpci_pmu.name, -1);
if (r)
return r;
--
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