49 lines
1.1 KiB
C
49 lines
1.1 KiB
C
// SPDX-License-Identifier: GPL-2.0
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/*
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* Dynamic Ftrace based Kprobes Optimization
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*/
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#include <linux/kprobes.h>
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#include <linux/ptrace.h>
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#include <linux/hardirq.h>
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#include <linux/preempt.h>
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#include <linux/ftrace.h>
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/* Ftrace callback handler for kprobes */
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void kprobe_ftrace_handler(unsigned long ip, unsigned long parent_ip,
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struct ftrace_ops *ops, struct pt_regs *regs)
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{
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struct kprobe *p;
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struct kprobe_ctlblk *kcb;
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p = get_kprobe((kprobe_opcode_t *)ip);
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if (unlikely(!p) || kprobe_disabled(p))
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return;
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kcb = get_kprobe_ctlblk();
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if (kprobe_running()) {
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kprobes_inc_nmissed_count(p);
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} else {
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regs->regs[28] -= MCOUNT_INSN_SIZE;
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__this_cpu_write(current_kprobe, p);
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kcb->kprobe_status = KPROBE_HIT_ACTIVE;
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if (!p->pre_handler || !p->pre_handler(p, regs)) {
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regs->regs[28] += MCOUNT_INSN_SIZE;
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if (unlikely(p->post_handler)) {
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kcb->kprobe_status = KPROBE_HIT_SSDONE;
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p->post_handler(p, regs, 0);
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}
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}
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__this_cpu_write(current_kprobe, NULL);
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}
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}
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NOKPROBE_SYMBOL(kprobe_ftrace_handler);
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int arch_prepare_kprobe_ftrace(struct kprobe *p)
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{
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p->ainsn.insn = NULL;
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p->ainsn.boostable = -1;
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return 0;
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}
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