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error checks. -----BEGIN PGP SIGNATURE----- iIoEABYIADIWIQRRSw7ePDh/lE+zeZMp5XQQmuv6qgUCXIukmxQccm9zdGVkdEBn b29kbWlzLm9yZwAKCRAp5XQQmuv6qi+PAQCKf6Yz7LZ3oBtjKy7jJRhkAn3Ie5Ls n7KOXnOGntO1cgD/RdynJcFtpwgDxuj7L/c3iInel0B/rdU5VLbglXy+2AA= =y/ft -----END PGP SIGNATURE----- Merge tag 'trace-v5.1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace Pull tracing fixes and cleanups from Steven Rostedt: "This contains a series of last minute clean ups, small fixes and error checks" * tag 'trace-v5.1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: tracing/probe: Verify alloc_trace_*probe() result tracing/probe: Check event/group naming rule at parsing tracing/probe: Check the size of argument name and body tracing/probe: Check event name length correctly tracing/probe: Check maxactive error cases tracing: kdb: Fix ftdump to not sleep trace/probes: Remove kernel doc style from non kernel doc comment tracing/probes: Make reserved_field_names static
1438 lines
32 KiB
C
1438 lines
32 KiB
C
// SPDX-License-Identifier: GPL-2.0
|
|
/*
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* uprobes-based tracing events
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*
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* Copyright (C) IBM Corporation, 2010-2012
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* Author: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
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*/
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#define pr_fmt(fmt) "trace_uprobe: " fmt
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#include <linux/ctype.h>
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#include <linux/module.h>
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#include <linux/uaccess.h>
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#include <linux/uprobes.h>
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#include <linux/namei.h>
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#include <linux/string.h>
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#include <linux/rculist.h>
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#include "trace_dynevent.h"
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#include "trace_probe.h"
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#include "trace_probe_tmpl.h"
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#define UPROBE_EVENT_SYSTEM "uprobes"
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struct uprobe_trace_entry_head {
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struct trace_entry ent;
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unsigned long vaddr[];
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};
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#define SIZEOF_TRACE_ENTRY(is_return) \
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(sizeof(struct uprobe_trace_entry_head) + \
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sizeof(unsigned long) * (is_return ? 2 : 1))
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#define DATAOF_TRACE_ENTRY(entry, is_return) \
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((void*)(entry) + SIZEOF_TRACE_ENTRY(is_return))
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struct trace_uprobe_filter {
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rwlock_t rwlock;
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int nr_systemwide;
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struct list_head perf_events;
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};
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static int trace_uprobe_create(int argc, const char **argv);
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static int trace_uprobe_show(struct seq_file *m, struct dyn_event *ev);
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static int trace_uprobe_release(struct dyn_event *ev);
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static bool trace_uprobe_is_busy(struct dyn_event *ev);
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static bool trace_uprobe_match(const char *system, const char *event,
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struct dyn_event *ev);
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static struct dyn_event_operations trace_uprobe_ops = {
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.create = trace_uprobe_create,
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.show = trace_uprobe_show,
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.is_busy = trace_uprobe_is_busy,
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.free = trace_uprobe_release,
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.match = trace_uprobe_match,
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};
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/*
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* uprobe event core functions
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*/
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struct trace_uprobe {
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struct dyn_event devent;
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struct trace_uprobe_filter filter;
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struct uprobe_consumer consumer;
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struct path path;
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struct inode *inode;
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char *filename;
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unsigned long offset;
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unsigned long ref_ctr_offset;
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unsigned long nhit;
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struct trace_probe tp;
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};
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static bool is_trace_uprobe(struct dyn_event *ev)
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{
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return ev->ops == &trace_uprobe_ops;
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}
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static struct trace_uprobe *to_trace_uprobe(struct dyn_event *ev)
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{
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return container_of(ev, struct trace_uprobe, devent);
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}
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/**
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* for_each_trace_uprobe - iterate over the trace_uprobe list
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* @pos: the struct trace_uprobe * for each entry
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* @dpos: the struct dyn_event * to use as a loop cursor
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*/
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#define for_each_trace_uprobe(pos, dpos) \
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for_each_dyn_event(dpos) \
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if (is_trace_uprobe(dpos) && (pos = to_trace_uprobe(dpos)))
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#define SIZEOF_TRACE_UPROBE(n) \
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(offsetof(struct trace_uprobe, tp.args) + \
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(sizeof(struct probe_arg) * (n)))
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static int register_uprobe_event(struct trace_uprobe *tu);
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static int unregister_uprobe_event(struct trace_uprobe *tu);
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struct uprobe_dispatch_data {
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struct trace_uprobe *tu;
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unsigned long bp_addr;
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};
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static int uprobe_dispatcher(struct uprobe_consumer *con, struct pt_regs *regs);
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static int uretprobe_dispatcher(struct uprobe_consumer *con,
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unsigned long func, struct pt_regs *regs);
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#ifdef CONFIG_STACK_GROWSUP
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static unsigned long adjust_stack_addr(unsigned long addr, unsigned int n)
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{
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return addr - (n * sizeof(long));
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}
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#else
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static unsigned long adjust_stack_addr(unsigned long addr, unsigned int n)
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{
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return addr + (n * sizeof(long));
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}
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#endif
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static unsigned long get_user_stack_nth(struct pt_regs *regs, unsigned int n)
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{
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unsigned long ret;
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unsigned long addr = user_stack_pointer(regs);
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addr = adjust_stack_addr(addr, n);
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if (copy_from_user(&ret, (void __force __user *) addr, sizeof(ret)))
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return 0;
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return ret;
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}
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/*
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* Uprobes-specific fetch functions
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*/
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static nokprobe_inline int
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probe_mem_read(void *dest, void *src, size_t size)
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{
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void __user *vaddr = (void __force __user *)src;
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return copy_from_user(dest, vaddr, size) ? -EFAULT : 0;
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}
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/*
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* Fetch a null-terminated string. Caller MUST set *(u32 *)dest with max
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* length and relative data location.
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*/
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static nokprobe_inline int
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fetch_store_string(unsigned long addr, void *dest, void *base)
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{
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long ret;
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u32 loc = *(u32 *)dest;
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int maxlen = get_loc_len(loc);
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u8 *dst = get_loc_data(dest, base);
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void __user *src = (void __force __user *) addr;
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if (unlikely(!maxlen))
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return -ENOMEM;
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ret = strncpy_from_user(dst, src, maxlen);
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if (ret >= 0) {
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if (ret == maxlen)
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dst[ret - 1] = '\0';
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else
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/*
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* Include the terminating null byte. In this case it
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* was copied by strncpy_from_user but not accounted
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* for in ret.
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*/
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ret++;
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*(u32 *)dest = make_data_loc(ret, (void *)dst - base);
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}
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return ret;
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}
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/* Return the length of string -- including null terminal byte */
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static nokprobe_inline int
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fetch_store_strlen(unsigned long addr)
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{
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int len;
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void __user *vaddr = (void __force __user *) addr;
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len = strnlen_user(vaddr, MAX_STRING_SIZE);
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return (len > MAX_STRING_SIZE) ? 0 : len;
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}
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static unsigned long translate_user_vaddr(unsigned long file_offset)
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{
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unsigned long base_addr;
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struct uprobe_dispatch_data *udd;
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udd = (void *) current->utask->vaddr;
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base_addr = udd->bp_addr - udd->tu->offset;
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return base_addr + file_offset;
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}
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/* Note that we don't verify it, since the code does not come from user space */
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static int
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process_fetch_insn(struct fetch_insn *code, struct pt_regs *regs, void *dest,
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void *base)
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{
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unsigned long val;
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/* 1st stage: get value from context */
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switch (code->op) {
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case FETCH_OP_REG:
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val = regs_get_register(regs, code->param);
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break;
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case FETCH_OP_STACK:
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val = get_user_stack_nth(regs, code->param);
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break;
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case FETCH_OP_STACKP:
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val = user_stack_pointer(regs);
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break;
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case FETCH_OP_RETVAL:
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val = regs_return_value(regs);
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break;
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case FETCH_OP_IMM:
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val = code->immediate;
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break;
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case FETCH_OP_FOFFS:
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val = translate_user_vaddr(code->immediate);
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break;
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default:
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return -EILSEQ;
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}
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code++;
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return process_fetch_insn_bottom(code, val, dest, base);
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}
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NOKPROBE_SYMBOL(process_fetch_insn)
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static inline void init_trace_uprobe_filter(struct trace_uprobe_filter *filter)
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{
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rwlock_init(&filter->rwlock);
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filter->nr_systemwide = 0;
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INIT_LIST_HEAD(&filter->perf_events);
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}
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static inline bool uprobe_filter_is_empty(struct trace_uprobe_filter *filter)
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{
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return !filter->nr_systemwide && list_empty(&filter->perf_events);
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}
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static inline bool is_ret_probe(struct trace_uprobe *tu)
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{
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return tu->consumer.ret_handler != NULL;
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}
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static bool trace_uprobe_is_busy(struct dyn_event *ev)
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{
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struct trace_uprobe *tu = to_trace_uprobe(ev);
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return trace_probe_is_enabled(&tu->tp);
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}
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static bool trace_uprobe_match(const char *system, const char *event,
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struct dyn_event *ev)
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{
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struct trace_uprobe *tu = to_trace_uprobe(ev);
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return strcmp(trace_event_name(&tu->tp.call), event) == 0 &&
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(!system || strcmp(tu->tp.call.class->system, system) == 0);
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}
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/*
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* Allocate new trace_uprobe and initialize it (including uprobes).
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*/
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static struct trace_uprobe *
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alloc_trace_uprobe(const char *group, const char *event, int nargs, bool is_ret)
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{
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struct trace_uprobe *tu;
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if (!event || !group)
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return ERR_PTR(-EINVAL);
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tu = kzalloc(SIZEOF_TRACE_UPROBE(nargs), GFP_KERNEL);
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if (!tu)
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return ERR_PTR(-ENOMEM);
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tu->tp.call.class = &tu->tp.class;
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tu->tp.call.name = kstrdup(event, GFP_KERNEL);
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if (!tu->tp.call.name)
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goto error;
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tu->tp.class.system = kstrdup(group, GFP_KERNEL);
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if (!tu->tp.class.system)
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goto error;
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dyn_event_init(&tu->devent, &trace_uprobe_ops);
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INIT_LIST_HEAD(&tu->tp.files);
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tu->consumer.handler = uprobe_dispatcher;
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if (is_ret)
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tu->consumer.ret_handler = uretprobe_dispatcher;
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init_trace_uprobe_filter(&tu->filter);
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return tu;
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error:
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kfree(tu->tp.call.name);
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kfree(tu);
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return ERR_PTR(-ENOMEM);
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}
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static void free_trace_uprobe(struct trace_uprobe *tu)
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{
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int i;
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if (!tu)
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return;
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for (i = 0; i < tu->tp.nr_args; i++)
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traceprobe_free_probe_arg(&tu->tp.args[i]);
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path_put(&tu->path);
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kfree(tu->tp.call.class->system);
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kfree(tu->tp.call.name);
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kfree(tu->filename);
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kfree(tu);
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}
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static struct trace_uprobe *find_probe_event(const char *event, const char *group)
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{
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struct dyn_event *pos;
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struct trace_uprobe *tu;
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|
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for_each_trace_uprobe(tu, pos)
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if (strcmp(trace_event_name(&tu->tp.call), event) == 0 &&
|
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strcmp(tu->tp.call.class->system, group) == 0)
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return tu;
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|
|
|
return NULL;
|
|
}
|
|
|
|
/* Unregister a trace_uprobe and probe_event */
|
|
static int unregister_trace_uprobe(struct trace_uprobe *tu)
|
|
{
|
|
int ret;
|
|
|
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ret = unregister_uprobe_event(tu);
|
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if (ret)
|
|
return ret;
|
|
|
|
dyn_event_remove(&tu->devent);
|
|
free_trace_uprobe(tu);
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Uprobe with multiple reference counter is not allowed. i.e.
|
|
* If inode and offset matches, reference counter offset *must*
|
|
* match as well. Though, there is one exception: If user is
|
|
* replacing old trace_uprobe with new one(same group/event),
|
|
* then we allow same uprobe with new reference counter as far
|
|
* as the new one does not conflict with any other existing
|
|
* ones.
|
|
*/
|
|
static struct trace_uprobe *find_old_trace_uprobe(struct trace_uprobe *new)
|
|
{
|
|
struct dyn_event *pos;
|
|
struct trace_uprobe *tmp, *old = NULL;
|
|
struct inode *new_inode = d_real_inode(new->path.dentry);
|
|
|
|
old = find_probe_event(trace_event_name(&new->tp.call),
|
|
new->tp.call.class->system);
|
|
|
|
for_each_trace_uprobe(tmp, pos) {
|
|
if ((old ? old != tmp : true) &&
|
|
new_inode == d_real_inode(tmp->path.dentry) &&
|
|
new->offset == tmp->offset &&
|
|
new->ref_ctr_offset != tmp->ref_ctr_offset) {
|
|
pr_warn("Reference counter offset mismatch.");
|
|
return ERR_PTR(-EINVAL);
|
|
}
|
|
}
|
|
return old;
|
|
}
|
|
|
|
/* Register a trace_uprobe and probe_event */
|
|
static int register_trace_uprobe(struct trace_uprobe *tu)
|
|
{
|
|
struct trace_uprobe *old_tu;
|
|
int ret;
|
|
|
|
mutex_lock(&event_mutex);
|
|
|
|
/* register as an event */
|
|
old_tu = find_old_trace_uprobe(tu);
|
|
if (IS_ERR(old_tu)) {
|
|
ret = PTR_ERR(old_tu);
|
|
goto end;
|
|
}
|
|
|
|
if (old_tu) {
|
|
/* delete old event */
|
|
ret = unregister_trace_uprobe(old_tu);
|
|
if (ret)
|
|
goto end;
|
|
}
|
|
|
|
ret = register_uprobe_event(tu);
|
|
if (ret) {
|
|
pr_warn("Failed to register probe event(%d)\n", ret);
|
|
goto end;
|
|
}
|
|
|
|
dyn_event_add(&tu->devent);
|
|
|
|
end:
|
|
mutex_unlock(&event_mutex);
|
|
|
|
return ret;
|
|
}
|
|
|
|
/*
|
|
* Argument syntax:
|
|
* - Add uprobe: p|r[:[GRP/]EVENT] PATH:OFFSET [FETCHARGS]
|
|
*
|
|
* - Remove uprobe: -:[GRP/]EVENT
|
|
*/
|
|
static int trace_uprobe_create(int argc, const char **argv)
|
|
{
|
|
struct trace_uprobe *tu;
|
|
const char *event = NULL, *group = UPROBE_EVENT_SYSTEM;
|
|
char *arg, *filename, *rctr, *rctr_end, *tmp;
|
|
char buf[MAX_EVENT_NAME_LEN];
|
|
struct path path;
|
|
unsigned long offset, ref_ctr_offset;
|
|
bool is_return = false;
|
|
int i, ret;
|
|
|
|
ret = 0;
|
|
ref_ctr_offset = 0;
|
|
|
|
/* argc must be >= 1 */
|
|
if (argv[0][0] == 'r')
|
|
is_return = true;
|
|
else if (argv[0][0] != 'p' || argc < 2)
|
|
return -ECANCELED;
|
|
|
|
if (argv[0][1] == ':')
|
|
event = &argv[0][2];
|
|
|
|
if (!strchr(argv[1], '/'))
|
|
return -ECANCELED;
|
|
|
|
filename = kstrdup(argv[1], GFP_KERNEL);
|
|
if (!filename)
|
|
return -ENOMEM;
|
|
|
|
/* Find the last occurrence, in case the path contains ':' too. */
|
|
arg = strrchr(filename, ':');
|
|
if (!arg || !isdigit(arg[1])) {
|
|
kfree(filename);
|
|
return -ECANCELED;
|
|
}
|
|
|
|
*arg++ = '\0';
|
|
ret = kern_path(filename, LOOKUP_FOLLOW, &path);
|
|
if (ret) {
|
|
kfree(filename);
|
|
return ret;
|
|
}
|
|
if (!d_is_reg(path.dentry)) {
|
|
ret = -EINVAL;
|
|
goto fail_address_parse;
|
|
}
|
|
|
|
/* Parse reference counter offset if specified. */
|
|
rctr = strchr(arg, '(');
|
|
if (rctr) {
|
|
rctr_end = strchr(rctr, ')');
|
|
if (rctr > rctr_end || *(rctr_end + 1) != 0) {
|
|
ret = -EINVAL;
|
|
pr_info("Invalid reference counter offset.\n");
|
|
goto fail_address_parse;
|
|
}
|
|
|
|
*rctr++ = '\0';
|
|
*rctr_end = '\0';
|
|
ret = kstrtoul(rctr, 0, &ref_ctr_offset);
|
|
if (ret) {
|
|
pr_info("Invalid reference counter offset.\n");
|
|
goto fail_address_parse;
|
|
}
|
|
}
|
|
|
|
/* Parse uprobe offset. */
|
|
ret = kstrtoul(arg, 0, &offset);
|
|
if (ret)
|
|
goto fail_address_parse;
|
|
|
|
argc -= 2;
|
|
argv += 2;
|
|
|
|
/* setup a probe */
|
|
if (event) {
|
|
ret = traceprobe_parse_event_name(&event, &group, buf);
|
|
if (ret)
|
|
goto fail_address_parse;
|
|
} else {
|
|
char *tail;
|
|
char *ptr;
|
|
|
|
tail = kstrdup(kbasename(filename), GFP_KERNEL);
|
|
if (!tail) {
|
|
ret = -ENOMEM;
|
|
goto fail_address_parse;
|
|
}
|
|
|
|
ptr = strpbrk(tail, ".-_");
|
|
if (ptr)
|
|
*ptr = '\0';
|
|
|
|
snprintf(buf, MAX_EVENT_NAME_LEN, "%c_%s_0x%lx", 'p', tail, offset);
|
|
event = buf;
|
|
kfree(tail);
|
|
}
|
|
|
|
tu = alloc_trace_uprobe(group, event, argc, is_return);
|
|
if (IS_ERR(tu)) {
|
|
ret = PTR_ERR(tu);
|
|
/* This must return -ENOMEM otherwise there is a bug */
|
|
WARN_ON_ONCE(ret != -ENOMEM);
|
|
goto fail_address_parse;
|
|
}
|
|
tu->offset = offset;
|
|
tu->ref_ctr_offset = ref_ctr_offset;
|
|
tu->path = path;
|
|
tu->filename = filename;
|
|
|
|
/* parse arguments */
|
|
for (i = 0; i < argc && i < MAX_TRACE_ARGS; i++) {
|
|
tmp = kstrdup(argv[i], GFP_KERNEL);
|
|
if (!tmp) {
|
|
ret = -ENOMEM;
|
|
goto error;
|
|
}
|
|
|
|
ret = traceprobe_parse_probe_arg(&tu->tp, i, tmp,
|
|
is_return ? TPARG_FL_RETURN : 0);
|
|
kfree(tmp);
|
|
if (ret)
|
|
goto error;
|
|
}
|
|
|
|
ret = register_trace_uprobe(tu);
|
|
if (ret)
|
|
goto error;
|
|
return 0;
|
|
|
|
error:
|
|
free_trace_uprobe(tu);
|
|
return ret;
|
|
|
|
fail_address_parse:
|
|
path_put(&path);
|
|
kfree(filename);
|
|
|
|
pr_info("Failed to parse address or file.\n");
|
|
|
|
return ret;
|
|
}
|
|
|
|
static int create_or_delete_trace_uprobe(int argc, char **argv)
|
|
{
|
|
int ret;
|
|
|
|
if (argv[0][0] == '-')
|
|
return dyn_event_release(argc, argv, &trace_uprobe_ops);
|
|
|
|
ret = trace_uprobe_create(argc, (const char **)argv);
|
|
return ret == -ECANCELED ? -EINVAL : ret;
|
|
}
|
|
|
|
static int trace_uprobe_release(struct dyn_event *ev)
|
|
{
|
|
struct trace_uprobe *tu = to_trace_uprobe(ev);
|
|
|
|
return unregister_trace_uprobe(tu);
|
|
}
|
|
|
|
/* Probes listing interfaces */
|
|
static int trace_uprobe_show(struct seq_file *m, struct dyn_event *ev)
|
|
{
|
|
struct trace_uprobe *tu = to_trace_uprobe(ev);
|
|
char c = is_ret_probe(tu) ? 'r' : 'p';
|
|
int i;
|
|
|
|
seq_printf(m, "%c:%s/%s %s:0x%0*lx", c, tu->tp.call.class->system,
|
|
trace_event_name(&tu->tp.call), tu->filename,
|
|
(int)(sizeof(void *) * 2), tu->offset);
|
|
|
|
if (tu->ref_ctr_offset)
|
|
seq_printf(m, "(0x%lx)", tu->ref_ctr_offset);
|
|
|
|
for (i = 0; i < tu->tp.nr_args; i++)
|
|
seq_printf(m, " %s=%s", tu->tp.args[i].name, tu->tp.args[i].comm);
|
|
|
|
seq_putc(m, '\n');
|
|
return 0;
|
|
}
|
|
|
|
static int probes_seq_show(struct seq_file *m, void *v)
|
|
{
|
|
struct dyn_event *ev = v;
|
|
|
|
if (!is_trace_uprobe(ev))
|
|
return 0;
|
|
|
|
return trace_uprobe_show(m, ev);
|
|
}
|
|
|
|
static const struct seq_operations probes_seq_op = {
|
|
.start = dyn_event_seq_start,
|
|
.next = dyn_event_seq_next,
|
|
.stop = dyn_event_seq_stop,
|
|
.show = probes_seq_show
|
|
};
|
|
|
|
static int probes_open(struct inode *inode, struct file *file)
|
|
{
|
|
int ret;
|
|
|
|
if ((file->f_mode & FMODE_WRITE) && (file->f_flags & O_TRUNC)) {
|
|
ret = dyn_events_release_all(&trace_uprobe_ops);
|
|
if (ret)
|
|
return ret;
|
|
}
|
|
|
|
return seq_open(file, &probes_seq_op);
|
|
}
|
|
|
|
static ssize_t probes_write(struct file *file, const char __user *buffer,
|
|
size_t count, loff_t *ppos)
|
|
{
|
|
return trace_parse_run_command(file, buffer, count, ppos,
|
|
create_or_delete_trace_uprobe);
|
|
}
|
|
|
|
static const struct file_operations uprobe_events_ops = {
|
|
.owner = THIS_MODULE,
|
|
.open = probes_open,
|
|
.read = seq_read,
|
|
.llseek = seq_lseek,
|
|
.release = seq_release,
|
|
.write = probes_write,
|
|
};
|
|
|
|
/* Probes profiling interfaces */
|
|
static int probes_profile_seq_show(struct seq_file *m, void *v)
|
|
{
|
|
struct dyn_event *ev = v;
|
|
struct trace_uprobe *tu;
|
|
|
|
if (!is_trace_uprobe(ev))
|
|
return 0;
|
|
|
|
tu = to_trace_uprobe(ev);
|
|
seq_printf(m, " %s %-44s %15lu\n", tu->filename,
|
|
trace_event_name(&tu->tp.call), tu->nhit);
|
|
return 0;
|
|
}
|
|
|
|
static const struct seq_operations profile_seq_op = {
|
|
.start = dyn_event_seq_start,
|
|
.next = dyn_event_seq_next,
|
|
.stop = dyn_event_seq_stop,
|
|
.show = probes_profile_seq_show
|
|
};
|
|
|
|
static int profile_open(struct inode *inode, struct file *file)
|
|
{
|
|
return seq_open(file, &profile_seq_op);
|
|
}
|
|
|
|
static const struct file_operations uprobe_profile_ops = {
|
|
.owner = THIS_MODULE,
|
|
.open = profile_open,
|
|
.read = seq_read,
|
|
.llseek = seq_lseek,
|
|
.release = seq_release,
|
|
};
|
|
|
|
struct uprobe_cpu_buffer {
|
|
struct mutex mutex;
|
|
void *buf;
|
|
};
|
|
static struct uprobe_cpu_buffer __percpu *uprobe_cpu_buffer;
|
|
static int uprobe_buffer_refcnt;
|
|
|
|
static int uprobe_buffer_init(void)
|
|
{
|
|
int cpu, err_cpu;
|
|
|
|
uprobe_cpu_buffer = alloc_percpu(struct uprobe_cpu_buffer);
|
|
if (uprobe_cpu_buffer == NULL)
|
|
return -ENOMEM;
|
|
|
|
for_each_possible_cpu(cpu) {
|
|
struct page *p = alloc_pages_node(cpu_to_node(cpu),
|
|
GFP_KERNEL, 0);
|
|
if (p == NULL) {
|
|
err_cpu = cpu;
|
|
goto err;
|
|
}
|
|
per_cpu_ptr(uprobe_cpu_buffer, cpu)->buf = page_address(p);
|
|
mutex_init(&per_cpu_ptr(uprobe_cpu_buffer, cpu)->mutex);
|
|
}
|
|
|
|
return 0;
|
|
|
|
err:
|
|
for_each_possible_cpu(cpu) {
|
|
if (cpu == err_cpu)
|
|
break;
|
|
free_page((unsigned long)per_cpu_ptr(uprobe_cpu_buffer, cpu)->buf);
|
|
}
|
|
|
|
free_percpu(uprobe_cpu_buffer);
|
|
return -ENOMEM;
|
|
}
|
|
|
|
static int uprobe_buffer_enable(void)
|
|
{
|
|
int ret = 0;
|
|
|
|
BUG_ON(!mutex_is_locked(&event_mutex));
|
|
|
|
if (uprobe_buffer_refcnt++ == 0) {
|
|
ret = uprobe_buffer_init();
|
|
if (ret < 0)
|
|
uprobe_buffer_refcnt--;
|
|
}
|
|
|
|
return ret;
|
|
}
|
|
|
|
static void uprobe_buffer_disable(void)
|
|
{
|
|
int cpu;
|
|
|
|
BUG_ON(!mutex_is_locked(&event_mutex));
|
|
|
|
if (--uprobe_buffer_refcnt == 0) {
|
|
for_each_possible_cpu(cpu)
|
|
free_page((unsigned long)per_cpu_ptr(uprobe_cpu_buffer,
|
|
cpu)->buf);
|
|
|
|
free_percpu(uprobe_cpu_buffer);
|
|
uprobe_cpu_buffer = NULL;
|
|
}
|
|
}
|
|
|
|
static struct uprobe_cpu_buffer *uprobe_buffer_get(void)
|
|
{
|
|
struct uprobe_cpu_buffer *ucb;
|
|
int cpu;
|
|
|
|
cpu = raw_smp_processor_id();
|
|
ucb = per_cpu_ptr(uprobe_cpu_buffer, cpu);
|
|
|
|
/*
|
|
* Use per-cpu buffers for fastest access, but we might migrate
|
|
* so the mutex makes sure we have sole access to it.
|
|
*/
|
|
mutex_lock(&ucb->mutex);
|
|
|
|
return ucb;
|
|
}
|
|
|
|
static void uprobe_buffer_put(struct uprobe_cpu_buffer *ucb)
|
|
{
|
|
mutex_unlock(&ucb->mutex);
|
|
}
|
|
|
|
static void __uprobe_trace_func(struct trace_uprobe *tu,
|
|
unsigned long func, struct pt_regs *regs,
|
|
struct uprobe_cpu_buffer *ucb, int dsize,
|
|
struct trace_event_file *trace_file)
|
|
{
|
|
struct uprobe_trace_entry_head *entry;
|
|
struct ring_buffer_event *event;
|
|
struct ring_buffer *buffer;
|
|
void *data;
|
|
int size, esize;
|
|
struct trace_event_call *call = &tu->tp.call;
|
|
|
|
WARN_ON(call != trace_file->event_call);
|
|
|
|
if (WARN_ON_ONCE(tu->tp.size + dsize > PAGE_SIZE))
|
|
return;
|
|
|
|
if (trace_trigger_soft_disabled(trace_file))
|
|
return;
|
|
|
|
esize = SIZEOF_TRACE_ENTRY(is_ret_probe(tu));
|
|
size = esize + tu->tp.size + dsize;
|
|
event = trace_event_buffer_lock_reserve(&buffer, trace_file,
|
|
call->event.type, size, 0, 0);
|
|
if (!event)
|
|
return;
|
|
|
|
entry = ring_buffer_event_data(event);
|
|
if (is_ret_probe(tu)) {
|
|
entry->vaddr[0] = func;
|
|
entry->vaddr[1] = instruction_pointer(regs);
|
|
data = DATAOF_TRACE_ENTRY(entry, true);
|
|
} else {
|
|
entry->vaddr[0] = instruction_pointer(regs);
|
|
data = DATAOF_TRACE_ENTRY(entry, false);
|
|
}
|
|
|
|
memcpy(data, ucb->buf, tu->tp.size + dsize);
|
|
|
|
event_trigger_unlock_commit(trace_file, buffer, event, entry, 0, 0);
|
|
}
|
|
|
|
/* uprobe handler */
|
|
static int uprobe_trace_func(struct trace_uprobe *tu, struct pt_regs *regs,
|
|
struct uprobe_cpu_buffer *ucb, int dsize)
|
|
{
|
|
struct event_file_link *link;
|
|
|
|
if (is_ret_probe(tu))
|
|
return 0;
|
|
|
|
rcu_read_lock();
|
|
list_for_each_entry_rcu(link, &tu->tp.files, list)
|
|
__uprobe_trace_func(tu, 0, regs, ucb, dsize, link->file);
|
|
rcu_read_unlock();
|
|
|
|
return 0;
|
|
}
|
|
|
|
static void uretprobe_trace_func(struct trace_uprobe *tu, unsigned long func,
|
|
struct pt_regs *regs,
|
|
struct uprobe_cpu_buffer *ucb, int dsize)
|
|
{
|
|
struct event_file_link *link;
|
|
|
|
rcu_read_lock();
|
|
list_for_each_entry_rcu(link, &tu->tp.files, list)
|
|
__uprobe_trace_func(tu, func, regs, ucb, dsize, link->file);
|
|
rcu_read_unlock();
|
|
}
|
|
|
|
/* Event entry printers */
|
|
static enum print_line_t
|
|
print_uprobe_event(struct trace_iterator *iter, int flags, struct trace_event *event)
|
|
{
|
|
struct uprobe_trace_entry_head *entry;
|
|
struct trace_seq *s = &iter->seq;
|
|
struct trace_uprobe *tu;
|
|
u8 *data;
|
|
|
|
entry = (struct uprobe_trace_entry_head *)iter->ent;
|
|
tu = container_of(event, struct trace_uprobe, tp.call.event);
|
|
|
|
if (is_ret_probe(tu)) {
|
|
trace_seq_printf(s, "%s: (0x%lx <- 0x%lx)",
|
|
trace_event_name(&tu->tp.call),
|
|
entry->vaddr[1], entry->vaddr[0]);
|
|
data = DATAOF_TRACE_ENTRY(entry, true);
|
|
} else {
|
|
trace_seq_printf(s, "%s: (0x%lx)",
|
|
trace_event_name(&tu->tp.call),
|
|
entry->vaddr[0]);
|
|
data = DATAOF_TRACE_ENTRY(entry, false);
|
|
}
|
|
|
|
if (print_probe_args(s, tu->tp.args, tu->tp.nr_args, data, entry) < 0)
|
|
goto out;
|
|
|
|
trace_seq_putc(s, '\n');
|
|
|
|
out:
|
|
return trace_handle_return(s);
|
|
}
|
|
|
|
typedef bool (*filter_func_t)(struct uprobe_consumer *self,
|
|
enum uprobe_filter_ctx ctx,
|
|
struct mm_struct *mm);
|
|
|
|
static int
|
|
probe_event_enable(struct trace_uprobe *tu, struct trace_event_file *file,
|
|
filter_func_t filter)
|
|
{
|
|
bool enabled = trace_probe_is_enabled(&tu->tp);
|
|
struct event_file_link *link = NULL;
|
|
int ret;
|
|
|
|
if (file) {
|
|
if (tu->tp.flags & TP_FLAG_PROFILE)
|
|
return -EINTR;
|
|
|
|
link = kmalloc(sizeof(*link), GFP_KERNEL);
|
|
if (!link)
|
|
return -ENOMEM;
|
|
|
|
link->file = file;
|
|
list_add_tail_rcu(&link->list, &tu->tp.files);
|
|
|
|
tu->tp.flags |= TP_FLAG_TRACE;
|
|
} else {
|
|
if (tu->tp.flags & TP_FLAG_TRACE)
|
|
return -EINTR;
|
|
|
|
tu->tp.flags |= TP_FLAG_PROFILE;
|
|
}
|
|
|
|
WARN_ON(!uprobe_filter_is_empty(&tu->filter));
|
|
|
|
if (enabled)
|
|
return 0;
|
|
|
|
ret = uprobe_buffer_enable();
|
|
if (ret)
|
|
goto err_flags;
|
|
|
|
tu->consumer.filter = filter;
|
|
tu->inode = d_real_inode(tu->path.dentry);
|
|
if (tu->ref_ctr_offset) {
|
|
ret = uprobe_register_refctr(tu->inode, tu->offset,
|
|
tu->ref_ctr_offset, &tu->consumer);
|
|
} else {
|
|
ret = uprobe_register(tu->inode, tu->offset, &tu->consumer);
|
|
}
|
|
|
|
if (ret)
|
|
goto err_buffer;
|
|
|
|
return 0;
|
|
|
|
err_buffer:
|
|
uprobe_buffer_disable();
|
|
|
|
err_flags:
|
|
if (file) {
|
|
list_del(&link->list);
|
|
kfree(link);
|
|
tu->tp.flags &= ~TP_FLAG_TRACE;
|
|
} else {
|
|
tu->tp.flags &= ~TP_FLAG_PROFILE;
|
|
}
|
|
return ret;
|
|
}
|
|
|
|
static void
|
|
probe_event_disable(struct trace_uprobe *tu, struct trace_event_file *file)
|
|
{
|
|
if (!trace_probe_is_enabled(&tu->tp))
|
|
return;
|
|
|
|
if (file) {
|
|
struct event_file_link *link;
|
|
|
|
link = find_event_file_link(&tu->tp, file);
|
|
if (!link)
|
|
return;
|
|
|
|
list_del_rcu(&link->list);
|
|
/* synchronize with u{,ret}probe_trace_func */
|
|
synchronize_rcu();
|
|
kfree(link);
|
|
|
|
if (!list_empty(&tu->tp.files))
|
|
return;
|
|
}
|
|
|
|
WARN_ON(!uprobe_filter_is_empty(&tu->filter));
|
|
|
|
uprobe_unregister(tu->inode, tu->offset, &tu->consumer);
|
|
tu->inode = NULL;
|
|
tu->tp.flags &= file ? ~TP_FLAG_TRACE : ~TP_FLAG_PROFILE;
|
|
|
|
uprobe_buffer_disable();
|
|
}
|
|
|
|
static int uprobe_event_define_fields(struct trace_event_call *event_call)
|
|
{
|
|
int ret, size;
|
|
struct uprobe_trace_entry_head field;
|
|
struct trace_uprobe *tu = event_call->data;
|
|
|
|
if (is_ret_probe(tu)) {
|
|
DEFINE_FIELD(unsigned long, vaddr[0], FIELD_STRING_FUNC, 0);
|
|
DEFINE_FIELD(unsigned long, vaddr[1], FIELD_STRING_RETIP, 0);
|
|
size = SIZEOF_TRACE_ENTRY(true);
|
|
} else {
|
|
DEFINE_FIELD(unsigned long, vaddr[0], FIELD_STRING_IP, 0);
|
|
size = SIZEOF_TRACE_ENTRY(false);
|
|
}
|
|
|
|
return traceprobe_define_arg_fields(event_call, size, &tu->tp);
|
|
}
|
|
|
|
#ifdef CONFIG_PERF_EVENTS
|
|
static bool
|
|
__uprobe_perf_filter(struct trace_uprobe_filter *filter, struct mm_struct *mm)
|
|
{
|
|
struct perf_event *event;
|
|
|
|
if (filter->nr_systemwide)
|
|
return true;
|
|
|
|
list_for_each_entry(event, &filter->perf_events, hw.tp_list) {
|
|
if (event->hw.target->mm == mm)
|
|
return true;
|
|
}
|
|
|
|
return false;
|
|
}
|
|
|
|
static inline bool
|
|
uprobe_filter_event(struct trace_uprobe *tu, struct perf_event *event)
|
|
{
|
|
return __uprobe_perf_filter(&tu->filter, event->hw.target->mm);
|
|
}
|
|
|
|
static int uprobe_perf_close(struct trace_uprobe *tu, struct perf_event *event)
|
|
{
|
|
bool done;
|
|
|
|
write_lock(&tu->filter.rwlock);
|
|
if (event->hw.target) {
|
|
list_del(&event->hw.tp_list);
|
|
done = tu->filter.nr_systemwide ||
|
|
(event->hw.target->flags & PF_EXITING) ||
|
|
uprobe_filter_event(tu, event);
|
|
} else {
|
|
tu->filter.nr_systemwide--;
|
|
done = tu->filter.nr_systemwide;
|
|
}
|
|
write_unlock(&tu->filter.rwlock);
|
|
|
|
if (!done)
|
|
return uprobe_apply(tu->inode, tu->offset, &tu->consumer, false);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int uprobe_perf_open(struct trace_uprobe *tu, struct perf_event *event)
|
|
{
|
|
bool done;
|
|
int err;
|
|
|
|
write_lock(&tu->filter.rwlock);
|
|
if (event->hw.target) {
|
|
/*
|
|
* event->parent != NULL means copy_process(), we can avoid
|
|
* uprobe_apply(). current->mm must be probed and we can rely
|
|
* on dup_mmap() which preserves the already installed bp's.
|
|
*
|
|
* attr.enable_on_exec means that exec/mmap will install the
|
|
* breakpoints we need.
|
|
*/
|
|
done = tu->filter.nr_systemwide ||
|
|
event->parent || event->attr.enable_on_exec ||
|
|
uprobe_filter_event(tu, event);
|
|
list_add(&event->hw.tp_list, &tu->filter.perf_events);
|
|
} else {
|
|
done = tu->filter.nr_systemwide;
|
|
tu->filter.nr_systemwide++;
|
|
}
|
|
write_unlock(&tu->filter.rwlock);
|
|
|
|
err = 0;
|
|
if (!done) {
|
|
err = uprobe_apply(tu->inode, tu->offset, &tu->consumer, true);
|
|
if (err)
|
|
uprobe_perf_close(tu, event);
|
|
}
|
|
return err;
|
|
}
|
|
|
|
static bool uprobe_perf_filter(struct uprobe_consumer *uc,
|
|
enum uprobe_filter_ctx ctx, struct mm_struct *mm)
|
|
{
|
|
struct trace_uprobe *tu;
|
|
int ret;
|
|
|
|
tu = container_of(uc, struct trace_uprobe, consumer);
|
|
read_lock(&tu->filter.rwlock);
|
|
ret = __uprobe_perf_filter(&tu->filter, mm);
|
|
read_unlock(&tu->filter.rwlock);
|
|
|
|
return ret;
|
|
}
|
|
|
|
static void __uprobe_perf_func(struct trace_uprobe *tu,
|
|
unsigned long func, struct pt_regs *regs,
|
|
struct uprobe_cpu_buffer *ucb, int dsize)
|
|
{
|
|
struct trace_event_call *call = &tu->tp.call;
|
|
struct uprobe_trace_entry_head *entry;
|
|
struct hlist_head *head;
|
|
void *data;
|
|
int size, esize;
|
|
int rctx;
|
|
|
|
if (bpf_prog_array_valid(call) && !trace_call_bpf(call, regs))
|
|
return;
|
|
|
|
esize = SIZEOF_TRACE_ENTRY(is_ret_probe(tu));
|
|
|
|
size = esize + tu->tp.size + dsize;
|
|
size = ALIGN(size + sizeof(u32), sizeof(u64)) - sizeof(u32);
|
|
if (WARN_ONCE(size > PERF_MAX_TRACE_SIZE, "profile buffer not large enough"))
|
|
return;
|
|
|
|
preempt_disable();
|
|
head = this_cpu_ptr(call->perf_events);
|
|
if (hlist_empty(head))
|
|
goto out;
|
|
|
|
entry = perf_trace_buf_alloc(size, NULL, &rctx);
|
|
if (!entry)
|
|
goto out;
|
|
|
|
if (is_ret_probe(tu)) {
|
|
entry->vaddr[0] = func;
|
|
entry->vaddr[1] = instruction_pointer(regs);
|
|
data = DATAOF_TRACE_ENTRY(entry, true);
|
|
} else {
|
|
entry->vaddr[0] = instruction_pointer(regs);
|
|
data = DATAOF_TRACE_ENTRY(entry, false);
|
|
}
|
|
|
|
memcpy(data, ucb->buf, tu->tp.size + dsize);
|
|
|
|
if (size - esize > tu->tp.size + dsize) {
|
|
int len = tu->tp.size + dsize;
|
|
|
|
memset(data + len, 0, size - esize - len);
|
|
}
|
|
|
|
perf_trace_buf_submit(entry, size, rctx, call->event.type, 1, regs,
|
|
head, NULL);
|
|
out:
|
|
preempt_enable();
|
|
}
|
|
|
|
/* uprobe profile handler */
|
|
static int uprobe_perf_func(struct trace_uprobe *tu, struct pt_regs *regs,
|
|
struct uprobe_cpu_buffer *ucb, int dsize)
|
|
{
|
|
if (!uprobe_perf_filter(&tu->consumer, 0, current->mm))
|
|
return UPROBE_HANDLER_REMOVE;
|
|
|
|
if (!is_ret_probe(tu))
|
|
__uprobe_perf_func(tu, 0, regs, ucb, dsize);
|
|
return 0;
|
|
}
|
|
|
|
static void uretprobe_perf_func(struct trace_uprobe *tu, unsigned long func,
|
|
struct pt_regs *regs,
|
|
struct uprobe_cpu_buffer *ucb, int dsize)
|
|
{
|
|
__uprobe_perf_func(tu, func, regs, ucb, dsize);
|
|
}
|
|
|
|
int bpf_get_uprobe_info(const struct perf_event *event, u32 *fd_type,
|
|
const char **filename, u64 *probe_offset,
|
|
bool perf_type_tracepoint)
|
|
{
|
|
const char *pevent = trace_event_name(event->tp_event);
|
|
const char *group = event->tp_event->class->system;
|
|
struct trace_uprobe *tu;
|
|
|
|
if (perf_type_tracepoint)
|
|
tu = find_probe_event(pevent, group);
|
|
else
|
|
tu = event->tp_event->data;
|
|
if (!tu)
|
|
return -EINVAL;
|
|
|
|
*fd_type = is_ret_probe(tu) ? BPF_FD_TYPE_URETPROBE
|
|
: BPF_FD_TYPE_UPROBE;
|
|
*filename = tu->filename;
|
|
*probe_offset = tu->offset;
|
|
return 0;
|
|
}
|
|
#endif /* CONFIG_PERF_EVENTS */
|
|
|
|
static int
|
|
trace_uprobe_register(struct trace_event_call *event, enum trace_reg type,
|
|
void *data)
|
|
{
|
|
struct trace_uprobe *tu = event->data;
|
|
struct trace_event_file *file = data;
|
|
|
|
switch (type) {
|
|
case TRACE_REG_REGISTER:
|
|
return probe_event_enable(tu, file, NULL);
|
|
|
|
case TRACE_REG_UNREGISTER:
|
|
probe_event_disable(tu, file);
|
|
return 0;
|
|
|
|
#ifdef CONFIG_PERF_EVENTS
|
|
case TRACE_REG_PERF_REGISTER:
|
|
return probe_event_enable(tu, NULL, uprobe_perf_filter);
|
|
|
|
case TRACE_REG_PERF_UNREGISTER:
|
|
probe_event_disable(tu, NULL);
|
|
return 0;
|
|
|
|
case TRACE_REG_PERF_OPEN:
|
|
return uprobe_perf_open(tu, data);
|
|
|
|
case TRACE_REG_PERF_CLOSE:
|
|
return uprobe_perf_close(tu, data);
|
|
|
|
#endif
|
|
default:
|
|
return 0;
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
static int uprobe_dispatcher(struct uprobe_consumer *con, struct pt_regs *regs)
|
|
{
|
|
struct trace_uprobe *tu;
|
|
struct uprobe_dispatch_data udd;
|
|
struct uprobe_cpu_buffer *ucb;
|
|
int dsize, esize;
|
|
int ret = 0;
|
|
|
|
|
|
tu = container_of(con, struct trace_uprobe, consumer);
|
|
tu->nhit++;
|
|
|
|
udd.tu = tu;
|
|
udd.bp_addr = instruction_pointer(regs);
|
|
|
|
current->utask->vaddr = (unsigned long) &udd;
|
|
|
|
if (WARN_ON_ONCE(!uprobe_cpu_buffer))
|
|
return 0;
|
|
|
|
dsize = __get_data_size(&tu->tp, regs);
|
|
esize = SIZEOF_TRACE_ENTRY(is_ret_probe(tu));
|
|
|
|
ucb = uprobe_buffer_get();
|
|
store_trace_args(ucb->buf, &tu->tp, regs, esize, dsize);
|
|
|
|
if (tu->tp.flags & TP_FLAG_TRACE)
|
|
ret |= uprobe_trace_func(tu, regs, ucb, dsize);
|
|
|
|
#ifdef CONFIG_PERF_EVENTS
|
|
if (tu->tp.flags & TP_FLAG_PROFILE)
|
|
ret |= uprobe_perf_func(tu, regs, ucb, dsize);
|
|
#endif
|
|
uprobe_buffer_put(ucb);
|
|
return ret;
|
|
}
|
|
|
|
static int uretprobe_dispatcher(struct uprobe_consumer *con,
|
|
unsigned long func, struct pt_regs *regs)
|
|
{
|
|
struct trace_uprobe *tu;
|
|
struct uprobe_dispatch_data udd;
|
|
struct uprobe_cpu_buffer *ucb;
|
|
int dsize, esize;
|
|
|
|
tu = container_of(con, struct trace_uprobe, consumer);
|
|
|
|
udd.tu = tu;
|
|
udd.bp_addr = func;
|
|
|
|
current->utask->vaddr = (unsigned long) &udd;
|
|
|
|
if (WARN_ON_ONCE(!uprobe_cpu_buffer))
|
|
return 0;
|
|
|
|
dsize = __get_data_size(&tu->tp, regs);
|
|
esize = SIZEOF_TRACE_ENTRY(is_ret_probe(tu));
|
|
|
|
ucb = uprobe_buffer_get();
|
|
store_trace_args(ucb->buf, &tu->tp, regs, esize, dsize);
|
|
|
|
if (tu->tp.flags & TP_FLAG_TRACE)
|
|
uretprobe_trace_func(tu, func, regs, ucb, dsize);
|
|
|
|
#ifdef CONFIG_PERF_EVENTS
|
|
if (tu->tp.flags & TP_FLAG_PROFILE)
|
|
uretprobe_perf_func(tu, func, regs, ucb, dsize);
|
|
#endif
|
|
uprobe_buffer_put(ucb);
|
|
return 0;
|
|
}
|
|
|
|
static struct trace_event_functions uprobe_funcs = {
|
|
.trace = print_uprobe_event
|
|
};
|
|
|
|
static inline void init_trace_event_call(struct trace_uprobe *tu,
|
|
struct trace_event_call *call)
|
|
{
|
|
INIT_LIST_HEAD(&call->class->fields);
|
|
call->event.funcs = &uprobe_funcs;
|
|
call->class->define_fields = uprobe_event_define_fields;
|
|
|
|
call->flags = TRACE_EVENT_FL_UPROBE;
|
|
call->class->reg = trace_uprobe_register;
|
|
call->data = tu;
|
|
}
|
|
|
|
static int register_uprobe_event(struct trace_uprobe *tu)
|
|
{
|
|
struct trace_event_call *call = &tu->tp.call;
|
|
int ret = 0;
|
|
|
|
init_trace_event_call(tu, call);
|
|
|
|
if (traceprobe_set_print_fmt(&tu->tp, is_ret_probe(tu)) < 0)
|
|
return -ENOMEM;
|
|
|
|
ret = register_trace_event(&call->event);
|
|
if (!ret) {
|
|
kfree(call->print_fmt);
|
|
return -ENODEV;
|
|
}
|
|
|
|
ret = trace_add_event_call(call);
|
|
|
|
if (ret) {
|
|
pr_info("Failed to register uprobe event: %s\n",
|
|
trace_event_name(call));
|
|
kfree(call->print_fmt);
|
|
unregister_trace_event(&call->event);
|
|
}
|
|
|
|
return ret;
|
|
}
|
|
|
|
static int unregister_uprobe_event(struct trace_uprobe *tu)
|
|
{
|
|
int ret;
|
|
|
|
/* tu->event is unregistered in trace_remove_event_call() */
|
|
ret = trace_remove_event_call(&tu->tp.call);
|
|
if (ret)
|
|
return ret;
|
|
kfree(tu->tp.call.print_fmt);
|
|
tu->tp.call.print_fmt = NULL;
|
|
return 0;
|
|
}
|
|
|
|
#ifdef CONFIG_PERF_EVENTS
|
|
struct trace_event_call *
|
|
create_local_trace_uprobe(char *name, unsigned long offs,
|
|
unsigned long ref_ctr_offset, bool is_return)
|
|
{
|
|
struct trace_uprobe *tu;
|
|
struct path path;
|
|
int ret;
|
|
|
|
ret = kern_path(name, LOOKUP_FOLLOW, &path);
|
|
if (ret)
|
|
return ERR_PTR(ret);
|
|
|
|
if (!d_is_reg(path.dentry)) {
|
|
path_put(&path);
|
|
return ERR_PTR(-EINVAL);
|
|
}
|
|
|
|
/*
|
|
* local trace_kprobes are not added to dyn_event, so they are never
|
|
* searched in find_trace_kprobe(). Therefore, there is no concern of
|
|
* duplicated name "DUMMY_EVENT" here.
|
|
*/
|
|
tu = alloc_trace_uprobe(UPROBE_EVENT_SYSTEM, "DUMMY_EVENT", 0,
|
|
is_return);
|
|
|
|
if (IS_ERR(tu)) {
|
|
pr_info("Failed to allocate trace_uprobe.(%d)\n",
|
|
(int)PTR_ERR(tu));
|
|
path_put(&path);
|
|
return ERR_CAST(tu);
|
|
}
|
|
|
|
tu->offset = offs;
|
|
tu->path = path;
|
|
tu->ref_ctr_offset = ref_ctr_offset;
|
|
tu->filename = kstrdup(name, GFP_KERNEL);
|
|
init_trace_event_call(tu, &tu->tp.call);
|
|
|
|
if (traceprobe_set_print_fmt(&tu->tp, is_ret_probe(tu)) < 0) {
|
|
ret = -ENOMEM;
|
|
goto error;
|
|
}
|
|
|
|
return &tu->tp.call;
|
|
error:
|
|
free_trace_uprobe(tu);
|
|
return ERR_PTR(ret);
|
|
}
|
|
|
|
void destroy_local_trace_uprobe(struct trace_event_call *event_call)
|
|
{
|
|
struct trace_uprobe *tu;
|
|
|
|
tu = container_of(event_call, struct trace_uprobe, tp.call);
|
|
|
|
kfree(tu->tp.call.print_fmt);
|
|
tu->tp.call.print_fmt = NULL;
|
|
|
|
free_trace_uprobe(tu);
|
|
}
|
|
#endif /* CONFIG_PERF_EVENTS */
|
|
|
|
/* Make a trace interface for controling probe points */
|
|
static __init int init_uprobe_trace(void)
|
|
{
|
|
struct dentry *d_tracer;
|
|
int ret;
|
|
|
|
ret = dyn_event_register(&trace_uprobe_ops);
|
|
if (ret)
|
|
return ret;
|
|
|
|
d_tracer = tracing_init_dentry();
|
|
if (IS_ERR(d_tracer))
|
|
return 0;
|
|
|
|
trace_create_file("uprobe_events", 0644, d_tracer,
|
|
NULL, &uprobe_events_ops);
|
|
/* Profile interface */
|
|
trace_create_file("uprobe_profile", 0444, d_tracer,
|
|
NULL, &uprobe_profile_ops);
|
|
return 0;
|
|
}
|
|
|
|
fs_initcall(init_uprobe_trace);
|