From ea08eeccae9297f7aabd2ef7f0c2517ac4549acc Mon Sep 17 00:00:00 2001
From: hc <hc@nodka.com>
Date: Tue, 20 Feb 2024 01:18:26 +0000
Subject: [PATCH] write in 30M
---
kernel/drivers/perf/arm_spe_pmu.c | 71 +++++++++++++++++++----------------
1 files changed, 39 insertions(+), 32 deletions(-)
diff --git a/kernel/drivers/perf/arm_spe_pmu.c b/kernel/drivers/perf/arm_spe_pmu.c
index 3623f64..6fbfcab 100644
--- a/kernel/drivers/perf/arm_spe_pmu.c
+++ b/kernel/drivers/perf/arm_spe_pmu.c
@@ -1,18 +1,7 @@
+// SPDX-License-Identifier: GPL-2.0-only
/*
* Perf support for the Statistical Profiling Extension, introduced as
* part of ARMv8.2.
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License version 2 as
- * published by the Free Software Foundation.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program. If not, see <http://www.gnu.org/licenses/>.
*
* Copyright (C) 2016 ARM Limited
*
@@ -38,6 +27,7 @@
#include <linux/of_address.h>
#include <linux/of_device.h>
#include <linux/perf_event.h>
+#include <linux/perf/arm_pmu.h>
#include <linux/platform_device.h>
#include <linux/printk.h>
#include <linux/slab.h>
@@ -48,6 +38,24 @@
#include <asm/cpufeature.h>
#include <asm/mmu.h>
#include <asm/sysreg.h>
+
+/*
+ * Cache if the event is allowed to trace Context information.
+ * This allows us to perform the check, i.e, perfmon_capable(),
+ * in the context of the event owner, once, during the event_init().
+ */
+#define SPE_PMU_HW_FLAGS_CX BIT(0)
+
+static void set_spe_event_has_cx(struct perf_event *event)
+{
+ if (IS_ENABLED(CONFIG_PID_IN_CONTEXTIDR) && perfmon_capable())
+ event->hw.flags |= SPE_PMU_HW_FLAGS_CX;
+}
+
+static bool get_spe_event_has_cx(struct perf_event *event)
+{
+ return !!(event->hw.flags & SPE_PMU_HW_FLAGS_CX);
+}
#define ARM_SPE_BUF_PAD_BYTE 0
@@ -284,7 +292,7 @@
if (!attr->exclude_kernel)
reg |= BIT(SYS_PMSCR_EL1_E1SPE_SHIFT);
- if (IS_ENABLED(CONFIG_PID_IN_CONTEXTIDR) && capable(CAP_SYS_ADMIN))
+ if (get_spe_event_has_cx(event))
reg |= BIT(SYS_PMSCR_EL1_CX_SHIFT);
return reg;
@@ -709,10 +717,10 @@
!(spe_pmu->features & SPE_PMU_FEAT_FILT_LAT))
return -EOPNOTSUPP;
+ set_spe_event_has_cx(event);
reg = arm_spe_event_to_pmscr(event);
- if (!capable(CAP_SYS_ADMIN) &&
+ if (!perfmon_capable() &&
(reg & (BIT(SYS_PMSCR_EL1_PA_SHIFT) |
- BIT(SYS_PMSCR_EL1_CX_SHIFT) |
BIT(SYS_PMSCR_EL1_PCT_SHIFT))))
return -EACCES;
@@ -841,7 +849,7 @@
* parts and give userspace a fighting chance of getting some
* useful data out of it.
*/
- if (!nr_pages || (snapshot && (nr_pages & 1)))
+ if (snapshot && (nr_pages & 1))
return NULL;
if (cpu == -1)
@@ -855,16 +863,8 @@
if (!pglist)
goto out_free_buf;
- for (i = 0; i < nr_pages; ++i) {
- struct page *page = virt_to_page(pages[i]);
-
- if (PagePrivate(page)) {
- pr_warn("unexpected high-order page for auxbuf!");
- goto out_free_pglist;
- }
-
+ for (i = 0; i < nr_pages; ++i)
pglist[i] = virt_to_page(pages[i]);
- }
buf->base = vmap(pglist, nr_pages, VM_MAP, PAGE_KERNEL);
if (!buf->base)
@@ -1020,7 +1020,7 @@
default:
dev_warn(dev, "unknown PMSIDR_EL1.Interval [%d]; assuming 8\n",
fld);
- /* Fallthrough */
+ fallthrough;
case 8:
spe_pmu->min_period = 4096;
}
@@ -1039,7 +1039,7 @@
default:
dev_warn(dev, "unknown PMSIDR_EL1.CountSize [%d]; assuming 2\n",
fld);
- /* Fallthrough */
+ fallthrough;
case 2:
spe_pmu->counter_sz = 12;
}
@@ -1151,10 +1151,8 @@
struct platform_device *pdev = spe_pmu->pdev;
int irq = platform_get_irq(pdev, 0);
- if (irq < 0) {
- dev_err(&pdev->dev, "failed to get IRQ (%d)\n", irq);
+ if (irq < 0)
return -ENXIO;
- }
if (!irq_is_percpu(irq)) {
dev_err(&pdev->dev, "expected PPI but got SPI (%d)\n", irq);
@@ -1174,8 +1172,15 @@
{ .compatible = "arm,statistical-profiling-extension-v1", .data = (void *)1 },
{ /* Sentinel */ },
};
+MODULE_DEVICE_TABLE(of, arm_spe_pmu_of_match);
-static int arm_spe_pmu_device_dt_probe(struct platform_device *pdev)
+static const struct platform_device_id arm_spe_match[] = {
+ { ARMV8_SPE_PDEV_NAME, 0},
+ { }
+};
+MODULE_DEVICE_TABLE(platform, arm_spe_match);
+
+static int arm_spe_pmu_device_probe(struct platform_device *pdev)
{
int ret;
struct arm_spe_pmu *spe_pmu;
@@ -1235,11 +1240,13 @@
}
static struct platform_driver arm_spe_pmu_driver = {
+ .id_table = arm_spe_match,
.driver = {
.name = DRVNAME,
.of_match_table = of_match_ptr(arm_spe_pmu_of_match),
+ .suppress_bind_attrs = true,
},
- .probe = arm_spe_pmu_device_dt_probe,
+ .probe = arm_spe_pmu_device_probe,
.remove = arm_spe_pmu_device_remove,
};
--
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