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authorYijie Yang <yijie.yang@oss.qualcomm.com>2026-08-11 16:46:47 +0800
committerRob Herring (Arm) <robh@kernel.org>2026-08-15 15:46:52 -0500
commite1c13aed4a1641550e8c9518c96f016e1d52d09b (patch)
tree61c2297688373db165cc857b7c7adcb147a5c419 /samples/kprobes/kprobe_example.c
downloadlinux-stable-e1c13aed4a1641550e8c9518c96f016e1d52d09b.tar.gz
linux-stable-e1c13aed4a1641550e8c9518c96f016e1d52d09b.zip
dt-bindings: interconnect: qcom-bwmon: Add Maili cpu-bwmon compatiblegrafted
Add the Qualcomm Maili SoC compatible string for the CPU bandwidth monitor (BWMONv4). This falls back to the sdm845-bwmon compatible, consistent with the existing pattern used by other recent SoCs such as sm8750 and kaanapali. Signed-off-by: Yijie Yang <yijie.yang@oss.qualcomm.com> Acked-by: Krzysztof Kozlowski <krzysztof.kozlowski@oss.qualcomm.com> Reviewed-by: Jingyi Wang <jingyi.wang@oss.qualcomm.com> Link: https://patch.msgid.link/20260811-bwmon-v2-1-80f7f150ab9e@oss.qualcomm.com Signed-off-by: Rob Herring (Arm) <robh@kernel.org>
Diffstat (limited to 'samples/kprobes/kprobe_example.c')
-rw-r--r--samples/kprobes/kprobe_example.c129
1 files changed, 129 insertions, 0 deletions
diff --git a/samples/kprobes/kprobe_example.c b/samples/kprobes/kprobe_example.c
new file mode 100644
index 000000000..53ec6c8b8
--- /dev/null
+++ b/samples/kprobes/kprobe_example.c
@@ -0,0 +1,129 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Here's a sample kernel module showing the use of kprobes to dump a
+ * stack trace and selected registers when kernel_clone() is called.
+ *
+ * For more information on theory of operation of kprobes, see
+ * Documentation/trace/kprobes.rst
+ *
+ * You will see the trace data in /var/log/messages and on the console
+ * whenever kernel_clone() is invoked to create a new process.
+ */
+
+#define pr_fmt(fmt) "%s: " fmt, __func__
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/kprobes.h>
+
+static char symbol[KSYM_NAME_LEN] = "kernel_clone";
+module_param_string(symbol, symbol, KSYM_NAME_LEN, 0644);
+
+/* For each probe you need to allocate a kprobe structure */
+static struct kprobe kp = {
+ .symbol_name = symbol,
+};
+
+/* kprobe pre_handler: called just before the probed instruction is executed */
+static int __kprobes handler_pre(struct kprobe *p, struct pt_regs *regs)
+{
+#ifdef CONFIG_X86
+ pr_info("<%s> p->addr = 0x%p, ip = %lx, flags = 0x%lx\n",
+ p->symbol_name, p->addr, regs->ip, regs->flags);
+#endif
+#ifdef CONFIG_PPC
+ pr_info("<%s> p->addr = 0x%p, nip = 0x%lx, msr = 0x%lx\n",
+ p->symbol_name, p->addr, regs->nip, regs->msr);
+#endif
+#ifdef CONFIG_MIPS
+ pr_info("<%s> p->addr = 0x%p, epc = 0x%lx, status = 0x%lx\n",
+ p->symbol_name, p->addr, regs->cp0_epc, regs->cp0_status);
+#endif
+#ifdef CONFIG_ARM64
+ pr_info("<%s> p->addr = 0x%p, pc = 0x%lx, pstate = 0x%lx\n",
+ p->symbol_name, p->addr, (long)regs->pc, (long)regs->pstate);
+#endif
+#ifdef CONFIG_ARM
+ pr_info("<%s> p->addr = 0x%p, pc = 0x%lx, cpsr = 0x%lx\n",
+ p->symbol_name, p->addr, (long)regs->ARM_pc, (long)regs->ARM_cpsr);
+#endif
+#ifdef CONFIG_RISCV
+ pr_info("<%s> p->addr = 0x%p, pc = 0x%lx, status = 0x%lx\n",
+ p->symbol_name, p->addr, regs->epc, regs->status);
+#endif
+#ifdef CONFIG_S390
+ pr_info("<%s> p->addr, 0x%p, ip = 0x%lx, flags = 0x%lx\n",
+ p->symbol_name, p->addr, regs->psw.addr, regs->flags);
+#endif
+#ifdef CONFIG_LOONGARCH
+ pr_info("<%s> p->addr = 0x%p, era = 0x%lx, estat = 0x%lx\n",
+ p->symbol_name, p->addr, regs->csr_era, regs->csr_estat);
+#endif
+
+ /* A dump_stack() here will give a stack backtrace */
+ return 0;
+}
+
+/* kprobe post_handler: called after the probed instruction is executed */
+static void __kprobes handler_post(struct kprobe *p, struct pt_regs *regs,
+ unsigned long flags)
+{
+#ifdef CONFIG_X86
+ pr_info("<%s> p->addr = 0x%p, flags = 0x%lx\n",
+ p->symbol_name, p->addr, regs->flags);
+#endif
+#ifdef CONFIG_PPC
+ pr_info("<%s> p->addr = 0x%p, msr = 0x%lx\n",
+ p->symbol_name, p->addr, regs->msr);
+#endif
+#ifdef CONFIG_MIPS
+ pr_info("<%s> p->addr = 0x%p, status = 0x%lx\n",
+ p->symbol_name, p->addr, regs->cp0_status);
+#endif
+#ifdef CONFIG_ARM64
+ pr_info("<%s> p->addr = 0x%p, pstate = 0x%lx\n",
+ p->symbol_name, p->addr, (long)regs->pstate);
+#endif
+#ifdef CONFIG_ARM
+ pr_info("<%s> p->addr = 0x%p, cpsr = 0x%lx\n",
+ p->symbol_name, p->addr, (long)regs->ARM_cpsr);
+#endif
+#ifdef CONFIG_RISCV
+ pr_info("<%s> p->addr = 0x%p, status = 0x%lx\n",
+ p->symbol_name, p->addr, regs->status);
+#endif
+#ifdef CONFIG_S390
+ pr_info("<%s> p->addr, 0x%p, flags = 0x%lx\n",
+ p->symbol_name, p->addr, regs->flags);
+#endif
+#ifdef CONFIG_LOONGARCH
+ pr_info("<%s> p->addr = 0x%p, estat = 0x%lx\n",
+ p->symbol_name, p->addr, regs->csr_estat);
+#endif
+}
+
+static int __init kprobe_init(void)
+{
+ int ret;
+ kp.pre_handler = handler_pre;
+ kp.post_handler = handler_post;
+
+ ret = register_kprobe(&kp);
+ if (ret < 0) {
+ pr_err("register_kprobe failed, returned %d\n", ret);
+ return ret;
+ }
+ pr_info("Planted kprobe at %p\n", kp.addr);
+ return 0;
+}
+
+static void __exit kprobe_exit(void)
+{
+ unregister_kprobe(&kp);
+ pr_info("kprobe at %p unregistered\n", kp.addr);
+}
+
+module_init(kprobe_init)
+module_exit(kprobe_exit)
+MODULE_DESCRIPTION("sample kernel module showing the use of kprobes");
+MODULE_LICENSE("GPL");