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- // SPDX-License-Identifier: GPL-2.0
- /*
- * uprobes-based tracing events
- *
- * Copyright (C) IBM Corporation, 2010-2012
- * Author: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
- */
- #define pr_fmt(fmt) "trace_uprobe: " fmt
- #include <linux/security.h>
- #include <linux/ctype.h>
- #include <linux/module.h>
- #include <linux/uaccess.h>
- #include <linux/uprobes.h>
- #include <linux/namei.h>
- #include <linux/string.h>
- #include <linux/rculist.h>
- #include "trace_dynevent.h"
- #include "trace_probe.h"
- #include "trace_probe_tmpl.h"
- #define UPROBE_EVENT_SYSTEM "uprobes"
- struct uprobe_trace_entry_head {
- struct trace_entry ent;
- unsigned long vaddr[];
- };
- #define SIZEOF_TRACE_ENTRY(is_return) \
- (sizeof(struct uprobe_trace_entry_head) + \
- sizeof(unsigned long) * (is_return ? 2 : 1))
- #define DATAOF_TRACE_ENTRY(entry, is_return) \
- ((void*)(entry) + SIZEOF_TRACE_ENTRY(is_return))
- static int trace_uprobe_create(int argc, const char **argv);
- static int trace_uprobe_show(struct seq_file *m, struct dyn_event *ev);
- static int trace_uprobe_release(struct dyn_event *ev);
- static bool trace_uprobe_is_busy(struct dyn_event *ev);
- static bool trace_uprobe_match(const char *system, const char *event,
- int argc, const char **argv, struct dyn_event *ev);
- static struct dyn_event_operations trace_uprobe_ops = {
- .create = trace_uprobe_create,
- .show = trace_uprobe_show,
- .is_busy = trace_uprobe_is_busy,
- .free = trace_uprobe_release,
- .match = trace_uprobe_match,
- };
- /*
- * uprobe event core functions
- */
- struct trace_uprobe {
- struct dyn_event devent;
- struct uprobe_consumer consumer;
- struct path path;
- struct inode *inode;
- char *filename;
- unsigned long offset;
- unsigned long ref_ctr_offset;
- unsigned long nhit;
- struct trace_probe tp;
- };
- static bool is_trace_uprobe(struct dyn_event *ev)
- {
- return ev->ops == &trace_uprobe_ops;
- }
- static struct trace_uprobe *to_trace_uprobe(struct dyn_event *ev)
- {
- return container_of(ev, struct trace_uprobe, devent);
- }
- /**
- * for_each_trace_uprobe - iterate over the trace_uprobe list
- * @pos: the struct trace_uprobe * for each entry
- * @dpos: the struct dyn_event * to use as a loop cursor
- */
- #define for_each_trace_uprobe(pos, dpos) \
- for_each_dyn_event(dpos) \
- if (is_trace_uprobe(dpos) && (pos = to_trace_uprobe(dpos)))
- #define SIZEOF_TRACE_UPROBE(n) \
- (offsetof(struct trace_uprobe, tp.args) + \
- (sizeof(struct probe_arg) * (n)))
- static int register_uprobe_event(struct trace_uprobe *tu);
- static int unregister_uprobe_event(struct trace_uprobe *tu);
- struct uprobe_dispatch_data {
- struct trace_uprobe *tu;
- unsigned long bp_addr;
- };
- static int uprobe_dispatcher(struct uprobe_consumer *con, struct pt_regs *regs);
- static int uretprobe_dispatcher(struct uprobe_consumer *con,
- unsigned long func, struct pt_regs *regs);
- #ifdef CONFIG_STACK_GROWSUP
- static unsigned long adjust_stack_addr(unsigned long addr, unsigned int n)
- {
- return addr - (n * sizeof(long));
- }
- #else
- static unsigned long adjust_stack_addr(unsigned long addr, unsigned int n)
- {
- return addr + (n * sizeof(long));
- }
- #endif
- static unsigned long get_user_stack_nth(struct pt_regs *regs, unsigned int n)
- {
- unsigned long ret;
- unsigned long addr = user_stack_pointer(regs);
- addr = adjust_stack_addr(addr, n);
- if (copy_from_user(&ret, (void __force __user *) addr, sizeof(ret)))
- return 0;
- return ret;
- }
- /*
- * Uprobes-specific fetch functions
- */
- static nokprobe_inline int
- probe_mem_read(void *dest, void *src, size_t size)
- {
- void __user *vaddr = (void __force __user *)src;
- return copy_from_user(dest, vaddr, size) ? -EFAULT : 0;
- }
- static nokprobe_inline int
- probe_mem_read_user(void *dest, void *src, size_t size)
- {
- return probe_mem_read(dest, src, size);
- }
- /*
- * Fetch a null-terminated string. Caller MUST set *(u32 *)dest with max
- * length and relative data location.
- */
- static nokprobe_inline int
- fetch_store_string(unsigned long addr, void *dest, void *base)
- {
- long ret;
- u32 loc = *(u32 *)dest;
- int maxlen = get_loc_len(loc);
- u8 *dst = get_loc_data(dest, base);
- void __user *src = (void __force __user *) addr;
- if (unlikely(!maxlen))
- return -ENOMEM;
- if (addr == FETCH_TOKEN_COMM)
- ret = strlcpy(dst, current->comm, maxlen);
- else
- ret = strncpy_from_user(dst, src, maxlen);
- if (ret >= 0) {
- if (ret == maxlen)
- dst[ret - 1] = '\0';
- else
- /*
- * Include the terminating null byte. In this case it
- * was copied by strncpy_from_user but not accounted
- * for in ret.
- */
- ret++;
- *(u32 *)dest = make_data_loc(ret, (void *)dst - base);
- }
- return ret;
- }
- static nokprobe_inline int
- fetch_store_string_user(unsigned long addr, void *dest, void *base)
- {
- return fetch_store_string(addr, dest, base);
- }
- /* Return the length of string -- including null terminal byte */
- static nokprobe_inline int
- fetch_store_strlen(unsigned long addr)
- {
- int len;
- void __user *vaddr = (void __force __user *) addr;
- if (addr == FETCH_TOKEN_COMM)
- len = strlen(current->comm) + 1;
- else
- len = strnlen_user(vaddr, MAX_STRING_SIZE);
- return (len > MAX_STRING_SIZE) ? 0 : len;
- }
- static nokprobe_inline int
- fetch_store_strlen_user(unsigned long addr)
- {
- return fetch_store_strlen(addr);
- }
- static unsigned long translate_user_vaddr(unsigned long file_offset)
- {
- unsigned long base_addr;
- struct uprobe_dispatch_data *udd;
- udd = (void *) current->utask->vaddr;
- base_addr = udd->bp_addr - udd->tu->offset;
- return base_addr + file_offset;
- }
- /* Note that we don't verify it, since the code does not come from user space */
- static int
- process_fetch_insn(struct fetch_insn *code, struct pt_regs *regs, void *dest,
- void *base)
- {
- unsigned long val;
- /* 1st stage: get value from context */
- switch (code->op) {
- case FETCH_OP_REG:
- val = regs_get_register(regs, code->param);
- break;
- case FETCH_OP_STACK:
- val = get_user_stack_nth(regs, code->param);
- break;
- case FETCH_OP_STACKP:
- val = user_stack_pointer(regs);
- break;
- case FETCH_OP_RETVAL:
- val = regs_return_value(regs);
- break;
- case FETCH_OP_IMM:
- val = code->immediate;
- break;
- case FETCH_OP_COMM:
- val = FETCH_TOKEN_COMM;
- break;
- case FETCH_OP_DATA:
- val = (unsigned long)code->data;
- break;
- case FETCH_OP_FOFFS:
- val = translate_user_vaddr(code->immediate);
- break;
- default:
- return -EILSEQ;
- }
- code++;
- return process_fetch_insn_bottom(code, val, dest, base);
- }
- NOKPROBE_SYMBOL(process_fetch_insn)
- static inline void init_trace_uprobe_filter(struct trace_uprobe_filter *filter)
- {
- rwlock_init(&filter->rwlock);
- filter->nr_systemwide = 0;
- INIT_LIST_HEAD(&filter->perf_events);
- }
- static inline bool uprobe_filter_is_empty(struct trace_uprobe_filter *filter)
- {
- return !filter->nr_systemwide && list_empty(&filter->perf_events);
- }
- static inline bool is_ret_probe(struct trace_uprobe *tu)
- {
- return tu->consumer.ret_handler != NULL;
- }
- static bool trace_uprobe_is_busy(struct dyn_event *ev)
- {
- struct trace_uprobe *tu = to_trace_uprobe(ev);
- return trace_probe_is_enabled(&tu->tp);
- }
- static bool trace_uprobe_match_command_head(struct trace_uprobe *tu,
- int argc, const char **argv)
- {
- char buf[MAX_ARGSTR_LEN + 1];
- int len;
- if (!argc)
- return true;
- len = strlen(tu->filename);
- if (strncmp(tu->filename, argv[0], len) || argv[0][len] != ':')
- return false;
- if (tu->ref_ctr_offset == 0)
- snprintf(buf, sizeof(buf), "0x%0*lx",
- (int)(sizeof(void *) * 2), tu->offset);
- else
- snprintf(buf, sizeof(buf), "0x%0*lx(0x%lx)",
- (int)(sizeof(void *) * 2), tu->offset,
- tu->ref_ctr_offset);
- if (strcmp(buf, &argv[0][len + 1]))
- return false;
- argc--; argv++;
- return trace_probe_match_command_args(&tu->tp, argc, argv);
- }
- static bool trace_uprobe_match(const char *system, const char *event,
- int argc, const char **argv, struct dyn_event *ev)
- {
- struct trace_uprobe *tu = to_trace_uprobe(ev);
- return strcmp(trace_probe_name(&tu->tp), event) == 0 &&
- (!system || strcmp(trace_probe_group_name(&tu->tp), system) == 0) &&
- trace_uprobe_match_command_head(tu, argc, argv);
- }
- static nokprobe_inline struct trace_uprobe *
- trace_uprobe_primary_from_call(struct trace_event_call *call)
- {
- struct trace_probe *tp;
- tp = trace_probe_primary_from_call(call);
- if (WARN_ON_ONCE(!tp))
- return NULL;
- return container_of(tp, struct trace_uprobe, tp);
- }
- /*
- * Allocate new trace_uprobe and initialize it (including uprobes).
- */
- static struct trace_uprobe *
- alloc_trace_uprobe(const char *group, const char *event, int nargs, bool is_ret)
- {
- struct trace_uprobe *tu;
- int ret;
- tu = kzalloc(SIZEOF_TRACE_UPROBE(nargs), GFP_KERNEL);
- if (!tu)
- return ERR_PTR(-ENOMEM);
- ret = trace_probe_init(&tu->tp, event, group, true);
- if (ret < 0)
- goto error;
- dyn_event_init(&tu->devent, &trace_uprobe_ops);
- tu->consumer.handler = uprobe_dispatcher;
- if (is_ret)
- tu->consumer.ret_handler = uretprobe_dispatcher;
- init_trace_uprobe_filter(tu->tp.event->filter);
- return tu;
- error:
- kfree(tu);
- return ERR_PTR(ret);
- }
- static void free_trace_uprobe(struct trace_uprobe *tu)
- {
- if (!tu)
- return;
- path_put(&tu->path);
- trace_probe_cleanup(&tu->tp);
- kfree(tu->filename);
- kfree(tu);
- }
- static struct trace_uprobe *find_probe_event(const char *event, const char *group)
- {
- struct dyn_event *pos;
- struct trace_uprobe *tu;
- for_each_trace_uprobe(tu, pos)
- if (strcmp(trace_probe_name(&tu->tp), event) == 0 &&
- strcmp(trace_probe_group_name(&tu->tp), group) == 0)
- return tu;
- return NULL;
- }
- /* Unregister a trace_uprobe and probe_event */
- static int unregister_trace_uprobe(struct trace_uprobe *tu)
- {
- int ret;
- if (trace_probe_has_sibling(&tu->tp))
- goto unreg;
- ret = unregister_uprobe_event(tu);
- if (ret)
- return ret;
- unreg:
- dyn_event_remove(&tu->devent);
- trace_probe_unlink(&tu->tp);
- free_trace_uprobe(tu);
- return 0;
- }
- static bool trace_uprobe_has_same_uprobe(struct trace_uprobe *orig,
- struct trace_uprobe *comp)
- {
- struct trace_probe_event *tpe = orig->tp.event;
- struct trace_probe *pos;
- struct inode *comp_inode = d_real_inode(comp->path.dentry);
- int i;
- list_for_each_entry(pos, &tpe->probes, list) {
- orig = container_of(pos, struct trace_uprobe, tp);
- if (comp_inode != d_real_inode(orig->path.dentry) ||
- comp->offset != orig->offset)
- continue;
- /*
- * trace_probe_compare_arg_type() ensured that nr_args and
- * each argument name and type are same. Let's compare comm.
- */
- for (i = 0; i < orig->tp.nr_args; i++) {
- if (strcmp(orig->tp.args[i].comm,
- comp->tp.args[i].comm))
- break;
- }
- if (i == orig->tp.nr_args)
- return true;
- }
- return false;
- }
- static int append_trace_uprobe(struct trace_uprobe *tu, struct trace_uprobe *to)
- {
- int ret;
- ret = trace_probe_compare_arg_type(&tu->tp, &to->tp);
- if (ret) {
- /* Note that argument starts index = 2 */
- trace_probe_log_set_index(ret + 1);
- trace_probe_log_err(0, DIFF_ARG_TYPE);
- return -EEXIST;
- }
- if (trace_uprobe_has_same_uprobe(to, tu)) {
- trace_probe_log_set_index(0);
- trace_probe_log_err(0, SAME_PROBE);
- return -EEXIST;
- }
- /* Append to existing event */
- ret = trace_probe_append(&tu->tp, &to->tp);
- if (!ret)
- dyn_event_add(&tu->devent);
- return ret;
- }
- /*
- * 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 int validate_ref_ctr_offset(struct trace_uprobe *new)
- {
- struct dyn_event *pos;
- struct trace_uprobe *tmp;
- struct inode *new_inode = d_real_inode(new->path.dentry);
- for_each_trace_uprobe(tmp, pos) {
- if (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 -EINVAL;
- }
- }
- return 0;
- }
- /* 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);
- ret = validate_ref_ctr_offset(tu);
- if (ret)
- goto end;
- /* register as an event */
- old_tu = find_probe_event(trace_probe_name(&tu->tp),
- trace_probe_group_name(&tu->tp));
- if (old_tu) {
- if (is_ret_probe(tu) != is_ret_probe(old_tu)) {
- trace_probe_log_set_index(0);
- trace_probe_log_err(0, DIFF_PROBE_TYPE);
- ret = -EEXIST;
- } else {
- ret = append_trace_uprobe(tu, old_tu);
- }
- goto end;
- }
- ret = register_uprobe_event(tu);
- if (ret) {
- if (ret == -EEXIST) {
- trace_probe_log_set_index(0);
- trace_probe_log_err(0, EVENT_EXIST);
- } else
- 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[%return][(REF)] [FETCHARGS]
- */
- 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;
- switch (argv[0][0]) {
- case 'r':
- is_return = true;
- break;
- case 'p':
- break;
- default:
- return -ECANCELED;
- }
- if (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;
- }
- trace_probe_log_init("trace_uprobe", argc, argv);
- trace_probe_log_set_index(1); /* filename is the 2nd argument */
- *arg++ = '\0';
- ret = kern_path(filename, LOOKUP_FOLLOW, &path);
- if (ret) {
- trace_probe_log_err(0, FILE_NOT_FOUND);
- kfree(filename);
- trace_probe_log_clear();
- return ret;
- }
- if (!d_is_reg(path.dentry)) {
- trace_probe_log_err(0, NO_REGULAR_FILE);
- ret = -EINVAL;
- goto fail_address_parse;
- }
- /* Parse reference counter offset if specified. */
- rctr = strchr(arg, '(');
- if (rctr) {
- rctr_end = strchr(rctr, ')');
- if (!rctr_end) {
- ret = -EINVAL;
- rctr_end = rctr + strlen(rctr);
- trace_probe_log_err(rctr_end - filename,
- REFCNT_OPEN_BRACE);
- goto fail_address_parse;
- } else if (rctr_end[1] != '\0') {
- ret = -EINVAL;
- trace_probe_log_err(rctr_end + 1 - filename,
- BAD_REFCNT_SUFFIX);
- goto fail_address_parse;
- }
- *rctr++ = '\0';
- *rctr_end = '\0';
- ret = kstrtoul(rctr, 0, &ref_ctr_offset);
- if (ret) {
- trace_probe_log_err(rctr - filename, BAD_REFCNT);
- goto fail_address_parse;
- }
- }
- /* Check if there is %return suffix */
- tmp = strchr(arg, '%');
- if (tmp) {
- if (!strcmp(tmp, "%return")) {
- *tmp = '\0';
- is_return = true;
- } else {
- trace_probe_log_err(tmp - filename, BAD_ADDR_SUFFIX);
- ret = -EINVAL;
- goto fail_address_parse;
- }
- }
- /* Parse uprobe offset. */
- ret = kstrtoul(arg, 0, &offset);
- if (ret) {
- trace_probe_log_err(arg - filename, BAD_UPROBE_OFFS);
- goto fail_address_parse;
- }
- /* setup a probe */
- trace_probe_log_set_index(0);
- if (event) {
- ret = traceprobe_parse_event_name(&event, &group, buf,
- event - argv[0]);
- 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);
- }
- argc -= 2;
- argv += 2;
- 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;
- }
- trace_probe_log_set_index(i + 2);
- ret = traceprobe_parse_probe_arg(&tu->tp, i, tmp,
- is_return ? TPARG_FL_RETURN : 0);
- kfree(tmp);
- if (ret)
- goto error;
- }
- ret = traceprobe_set_print_fmt(&tu->tp, is_ret_probe(tu));
- if (ret < 0)
- goto error;
- ret = register_trace_uprobe(tu);
- if (!ret)
- goto out;
- error:
- free_trace_uprobe(tu);
- out:
- trace_probe_log_clear();
- return ret;
- fail_address_parse:
- trace_probe_log_clear();
- path_put(&path);
- kfree(filename);
- 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, trace_probe_group_name(&tu->tp),
- trace_probe_name(&tu->tp), 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;
- ret = security_locked_down(LOCKDOWN_TRACEFS);
- if (ret)
- return 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_probe_name(&tu->tp), 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)
- {
- int ret;
- ret = security_locked_down(LOCKDOWN_TRACEFS);
- if (ret)
- return ret;
- 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 trace_buffer *buffer;
- struct ring_buffer_event *event;
- void *data;
- int size, esize;
- struct trace_event_call *call = trace_probe_event_call(&tu->tp);
- 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();
- trace_probe_for_each_link_rcu(link, &tu->tp)
- __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();
- trace_probe_for_each_link_rcu(link, &tu->tp)
- __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 = trace_uprobe_primary_from_call(
- container_of(event, struct trace_event_call, event));
- if (unlikely(!tu))
- goto out;
- if (is_ret_probe(tu)) {
- trace_seq_printf(s, "%s: (0x%lx <- 0x%lx)",
- trace_probe_name(&tu->tp),
- entry->vaddr[1], entry->vaddr[0]);
- data = DATAOF_TRACE_ENTRY(entry, true);
- } else {
- trace_seq_printf(s, "%s: (0x%lx)",
- trace_probe_name(&tu->tp),
- 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 trace_uprobe_enable(struct trace_uprobe *tu, filter_func_t filter)
- {
- int ret;
- 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)
- tu->inode = NULL;
- return ret;
- }
- static void __probe_event_disable(struct trace_probe *tp)
- {
- struct trace_probe *pos;
- struct trace_uprobe *tu;
- tu = container_of(tp, struct trace_uprobe, tp);
- WARN_ON(!uprobe_filter_is_empty(tu->tp.event->filter));
- list_for_each_entry(pos, trace_probe_probe_list(tp), list) {
- tu = container_of(pos, struct trace_uprobe, tp);
- if (!tu->inode)
- continue;
- uprobe_unregister(tu->inode, tu->offset, &tu->consumer);
- tu->inode = NULL;
- }
- }
- static int probe_event_enable(struct trace_event_call *call,
- struct trace_event_file *file, filter_func_t filter)
- {
- struct trace_probe *pos, *tp;
- struct trace_uprobe *tu;
- bool enabled;
- int ret;
- tp = trace_probe_primary_from_call(call);
- if (WARN_ON_ONCE(!tp))
- return -ENODEV;
- enabled = trace_probe_is_enabled(tp);
- /* This may also change "enabled" state */
- if (file) {
- if (trace_probe_test_flag(tp, TP_FLAG_PROFILE))
- return -EINTR;
- ret = trace_probe_add_file(tp, file);
- if (ret < 0)
- return ret;
- } else {
- if (trace_probe_test_flag(tp, TP_FLAG_TRACE))
- return -EINTR;
- trace_probe_set_flag(tp, TP_FLAG_PROFILE);
- }
- tu = container_of(tp, struct trace_uprobe, tp);
- WARN_ON(!uprobe_filter_is_empty(tu->tp.event->filter));
- if (enabled)
- return 0;
- ret = uprobe_buffer_enable();
- if (ret)
- goto err_flags;
- list_for_each_entry(pos, trace_probe_probe_list(tp), list) {
- tu = container_of(pos, struct trace_uprobe, tp);
- ret = trace_uprobe_enable(tu, filter);
- if (ret) {
- __probe_event_disable(tp);
- goto err_buffer;
- }
- }
- return 0;
- err_buffer:
- uprobe_buffer_disable();
- err_flags:
- if (file)
- trace_probe_remove_file(tp, file);
- else
- trace_probe_clear_flag(tp, TP_FLAG_PROFILE);
- return ret;
- }
- static void probe_event_disable(struct trace_event_call *call,
- struct trace_event_file *file)
- {
- struct trace_probe *tp;
- tp = trace_probe_primary_from_call(call);
- if (WARN_ON_ONCE(!tp))
- return;
- if (!trace_probe_is_enabled(tp))
- return;
- if (file) {
- if (trace_probe_remove_file(tp, file) < 0)
- return;
- if (trace_probe_is_enabled(tp))
- return;
- } else
- trace_probe_clear_flag(tp, TP_FLAG_PROFILE);
- __probe_event_disable(tp);
- 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;
- tu = trace_uprobe_primary_from_call(event_call);
- if (unlikely(!tu))
- return -ENODEV;
- 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
- trace_uprobe_filter_event(struct trace_uprobe_filter *filter,
- struct perf_event *event)
- {
- return __uprobe_perf_filter(filter, event->hw.target->mm);
- }
- static bool trace_uprobe_filter_remove(struct trace_uprobe_filter *filter,
- struct perf_event *event)
- {
- bool done;
- write_lock(&filter->rwlock);
- if (event->hw.target) {
- list_del(&event->hw.tp_list);
- done = filter->nr_systemwide ||
- (event->hw.target->flags & PF_EXITING) ||
- trace_uprobe_filter_event(filter, event);
- } else {
- filter->nr_systemwide--;
- done = filter->nr_systemwide;
- }
- write_unlock(&filter->rwlock);
- return done;
- }
- /* This returns true if the filter always covers target mm */
- static bool trace_uprobe_filter_add(struct trace_uprobe_filter *filter,
- struct perf_event *event)
- {
- bool done;
- write_lock(&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 = filter->nr_systemwide ||
- event->parent || event->attr.enable_on_exec ||
- trace_uprobe_filter_event(filter, event);
- list_add(&event->hw.tp_list, &filter->perf_events);
- } else {
- done = filter->nr_systemwide;
- filter->nr_systemwide++;
- }
- write_unlock(&filter->rwlock);
- return done;
- }
- static int uprobe_perf_close(struct trace_event_call *call,
- struct perf_event *event)
- {
- struct trace_probe *pos, *tp;
- struct trace_uprobe *tu;
- int ret = 0;
- tp = trace_probe_primary_from_call(call);
- if (WARN_ON_ONCE(!tp))
- return -ENODEV;
- tu = container_of(tp, struct trace_uprobe, tp);
- if (trace_uprobe_filter_remove(tu->tp.event->filter, event))
- return 0;
- list_for_each_entry(pos, trace_probe_probe_list(tp), list) {
- tu = container_of(pos, struct trace_uprobe, tp);
- ret = uprobe_apply(tu->inode, tu->offset, &tu->consumer, false);
- if (ret)
- break;
- }
- return ret;
- }
- static int uprobe_perf_open(struct trace_event_call *call,
- struct perf_event *event)
- {
- struct trace_probe *pos, *tp;
- struct trace_uprobe *tu;
- int err = 0;
- tp = trace_probe_primary_from_call(call);
- if (WARN_ON_ONCE(!tp))
- return -ENODEV;
- tu = container_of(tp, struct trace_uprobe, tp);
- if (trace_uprobe_filter_add(tu->tp.event->filter, event))
- return 0;
- list_for_each_entry(pos, trace_probe_probe_list(tp), list) {
- tu = container_of(pos, struct trace_uprobe, tp);
- err = uprobe_apply(tu->inode, tu->offset, &tu->consumer, true);
- if (err) {
- uprobe_perf_close(call, event);
- break;
- }
- }
- return err;
- }
- static bool uprobe_perf_filter(struct uprobe_consumer *uc,
- enum uprobe_filter_ctx ctx, struct mm_struct *mm)
- {
- struct trace_uprobe_filter *filter;
- struct trace_uprobe *tu;
- int ret;
- tu = container_of(uc, struct trace_uprobe, consumer);
- filter = tu->tp.event->filter;
- read_lock(&filter->rwlock);
- ret = __uprobe_perf_filter(filter, mm);
- read_unlock(&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 = trace_probe_event_call(&tu->tp);
- struct uprobe_trace_entry_head *entry;
- struct hlist_head *head;
- void *data;
- int size, esize;
- int rctx;
- if (bpf_prog_array_valid(call)) {
- u32 ret;
- preempt_disable();
- ret = trace_call_bpf(call, regs);
- preempt_enable();
- if (!ret)
- 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 = trace_uprobe_primary_from_call(event->tp_event);
- 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_event_file *file = data;
- switch (type) {
- case TRACE_REG_REGISTER:
- return probe_event_enable(event, file, NULL);
- case TRACE_REG_UNREGISTER:
- probe_event_disable(event, file);
- return 0;
- #ifdef CONFIG_PERF_EVENTS
- case TRACE_REG_PERF_REGISTER:
- return probe_event_enable(event, NULL, uprobe_perf_filter);
- case TRACE_REG_PERF_UNREGISTER:
- probe_event_disable(event, NULL);
- return 0;
- case TRACE_REG_PERF_OPEN:
- return uprobe_perf_open(event, data);
- case TRACE_REG_PERF_CLOSE:
- return uprobe_perf_close(event, data);
- #endif
- default:
- 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 (trace_probe_test_flag(&tu->tp, TP_FLAG_TRACE))
- ret |= uprobe_trace_func(tu, regs, ucb, dsize);
- #ifdef CONFIG_PERF_EVENTS
- if (trace_probe_test_flag(&tu->tp, 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 (trace_probe_test_flag(&tu->tp, TP_FLAG_TRACE))
- uretprobe_trace_func(tu, func, regs, ucb, dsize);
- #ifdef CONFIG_PERF_EVENTS
- if (trace_probe_test_flag(&tu->tp, 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 struct trace_event_fields uprobe_fields_array[] = {
- { .type = TRACE_FUNCTION_TYPE,
- .define_fields = uprobe_event_define_fields },
- {}
- };
- static inline void init_trace_event_call(struct trace_uprobe *tu)
- {
- struct trace_event_call *call = trace_probe_event_call(&tu->tp);
- call->event.funcs = &uprobe_funcs;
- call->class->fields_array = uprobe_fields_array;
- call->flags = TRACE_EVENT_FL_UPROBE | TRACE_EVENT_FL_CAP_ANY;
- call->class->reg = trace_uprobe_register;
- }
- static int register_uprobe_event(struct trace_uprobe *tu)
- {
- init_trace_event_call(tu);
- return trace_probe_register_event_call(&tu->tp);
- }
- static int unregister_uprobe_event(struct trace_uprobe *tu)
- {
- return trace_probe_unregister_event_call(&tu->tp);
- }
- #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);
- if (traceprobe_set_print_fmt(&tu->tp, is_ret_probe(tu)) < 0) {
- ret = -ENOMEM;
- goto error;
- }
- return trace_probe_event_call(&tu->tp);
- 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 = trace_uprobe_primary_from_call(event_call);
- free_trace_uprobe(tu);
- }
- #endif /* CONFIG_PERF_EVENTS */
- /* Make a trace interface for controling probe points */
- static __init int init_uprobe_trace(void)
- {
- int ret;
- ret = dyn_event_register(&trace_uprobe_ops);
- if (ret)
- return ret;
- ret = tracing_init_dentry();
- if (ret)
- return 0;
- trace_create_file("uprobe_events", 0644, NULL,
- NULL, &uprobe_events_ops);
- /* Profile interface */
- trace_create_file("uprobe_profile", 0444, NULL,
- NULL, &uprobe_profile_ops);
- return 0;
- }
- fs_initcall(init_uprobe_trace);
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