summaryrefslogtreecommitdiff
path: root/kernel/trace/trace_kprobe.c
diff options
context:
space:
mode:
Diffstat (limited to 'kernel/trace/trace_kprobe.c')
-rw-r--r--kernel/trace/trace_kprobe.c1495
1 files changed, 1495 insertions, 0 deletions
diff --git a/kernel/trace/trace_kprobe.c b/kernel/trace/trace_kprobe.c
new file mode 100644
index 000000000..d0ce590f0
--- /dev/null
+++ b/kernel/trace/trace_kprobe.c
@@ -0,0 +1,1495 @@
+/*
+ * Kprobes-based tracing events
+ *
+ * Created by Masami Hiramatsu <mhiramat@redhat.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ */
+
+#include <linux/module.h>
+#include <linux/uaccess.h>
+
+#include "trace_probe.h"
+
+#define KPROBE_EVENT_SYSTEM "kprobes"
+
+/**
+ * Kprobe event core functions
+ */
+struct trace_kprobe {
+ struct list_head list;
+ struct kretprobe rp; /* Use rp.kp for kprobe use */
+ unsigned long nhit;
+ const char *symbol; /* symbol name */
+ struct trace_probe tp;
+};
+
+#define SIZEOF_TRACE_KPROBE(n) \
+ (offsetof(struct trace_kprobe, tp.args) + \
+ (sizeof(struct probe_arg) * (n)))
+
+
+static nokprobe_inline bool trace_kprobe_is_return(struct trace_kprobe *tk)
+{
+ return tk->rp.handler != NULL;
+}
+
+static nokprobe_inline const char *trace_kprobe_symbol(struct trace_kprobe *tk)
+{
+ return tk->symbol ? tk->symbol : "unknown";
+}
+
+static nokprobe_inline unsigned long trace_kprobe_offset(struct trace_kprobe *tk)
+{
+ return tk->rp.kp.offset;
+}
+
+static nokprobe_inline bool trace_kprobe_has_gone(struct trace_kprobe *tk)
+{
+ return !!(kprobe_gone(&tk->rp.kp));
+}
+
+static nokprobe_inline bool trace_kprobe_within_module(struct trace_kprobe *tk,
+ struct module *mod)
+{
+ int len = strlen(mod->name);
+ const char *name = trace_kprobe_symbol(tk);
+ return strncmp(mod->name, name, len) == 0 && name[len] == ':';
+}
+
+static nokprobe_inline bool trace_kprobe_is_on_module(struct trace_kprobe *tk)
+{
+ return !!strchr(trace_kprobe_symbol(tk), ':');
+}
+
+static int register_kprobe_event(struct trace_kprobe *tk);
+static int unregister_kprobe_event(struct trace_kprobe *tk);
+
+static DEFINE_MUTEX(probe_lock);
+static LIST_HEAD(probe_list);
+
+static int kprobe_dispatcher(struct kprobe *kp, struct pt_regs *regs);
+static int kretprobe_dispatcher(struct kretprobe_instance *ri,
+ struct pt_regs *regs);
+
+/* Memory fetching by symbol */
+struct symbol_cache {
+ char *symbol;
+ long offset;
+ unsigned long addr;
+};
+
+unsigned long update_symbol_cache(struct symbol_cache *sc)
+{
+ sc->addr = (unsigned long)kallsyms_lookup_name(sc->symbol);
+
+ if (sc->addr)
+ sc->addr += sc->offset;
+
+ return sc->addr;
+}
+
+void free_symbol_cache(struct symbol_cache *sc)
+{
+ kfree(sc->symbol);
+ kfree(sc);
+}
+
+struct symbol_cache *alloc_symbol_cache(const char *sym, long offset)
+{
+ struct symbol_cache *sc;
+
+ if (!sym || strlen(sym) == 0)
+ return NULL;
+
+ sc = kzalloc(sizeof(struct symbol_cache), GFP_KERNEL);
+ if (!sc)
+ return NULL;
+
+ sc->symbol = kstrdup(sym, GFP_KERNEL);
+ if (!sc->symbol) {
+ kfree(sc);
+ return NULL;
+ }
+ sc->offset = offset;
+ update_symbol_cache(sc);
+
+ return sc;
+}
+
+/*
+ * Kprobes-specific fetch functions
+ */
+#define DEFINE_FETCH_stack(type) \
+static void FETCH_FUNC_NAME(stack, type)(struct pt_regs *regs, \
+ void *offset, void *dest) \
+{ \
+ *(type *)dest = (type)regs_get_kernel_stack_nth(regs, \
+ (unsigned int)((unsigned long)offset)); \
+} \
+NOKPROBE_SYMBOL(FETCH_FUNC_NAME(stack, type));
+
+DEFINE_BASIC_FETCH_FUNCS(stack)
+/* No string on the stack entry */
+#define fetch_stack_string NULL
+#define fetch_stack_string_size NULL
+
+#define DEFINE_FETCH_memory(type) \
+static void FETCH_FUNC_NAME(memory, type)(struct pt_regs *regs, \
+ void *addr, void *dest) \
+{ \
+ type retval; \
+ if (probe_kernel_address(addr, retval)) \
+ *(type *)dest = 0; \
+ else \
+ *(type *)dest = retval; \
+} \
+NOKPROBE_SYMBOL(FETCH_FUNC_NAME(memory, type));
+
+DEFINE_BASIC_FETCH_FUNCS(memory)
+/*
+ * Fetch a null-terminated string. Caller MUST set *(u32 *)dest with max
+ * length and relative data location.
+ */
+static void FETCH_FUNC_NAME(memory, string)(struct pt_regs *regs,
+ void *addr, void *dest)
+{
+ long ret;
+ int maxlen = get_rloc_len(*(u32 *)dest);
+ u8 *dst = get_rloc_data(dest);
+ u8 *src = addr;
+ mm_segment_t old_fs = get_fs();
+
+ if (!maxlen)
+ return;
+
+ /*
+ * Try to get string again, since the string can be changed while
+ * probing.
+ */
+ set_fs(KERNEL_DS);
+ pagefault_disable();
+
+ do
+ ret = __copy_from_user_inatomic(dst++, src++, 1);
+ while (dst[-1] && ret == 0 && src - (u8 *)addr < maxlen);
+
+ dst[-1] = '\0';
+ pagefault_enable();
+ set_fs(old_fs);
+
+ if (ret < 0) { /* Failed to fetch string */
+ ((u8 *)get_rloc_data(dest))[0] = '\0';
+ *(u32 *)dest = make_data_rloc(0, get_rloc_offs(*(u32 *)dest));
+ } else {
+ *(u32 *)dest = make_data_rloc(src - (u8 *)addr,
+ get_rloc_offs(*(u32 *)dest));
+ }
+}
+NOKPROBE_SYMBOL(FETCH_FUNC_NAME(memory, string));
+
+/* Return the length of string -- including null terminal byte */
+static void FETCH_FUNC_NAME(memory, string_size)(struct pt_regs *regs,
+ void *addr, void *dest)
+{
+ mm_segment_t old_fs;
+ int ret, len = 0;
+ u8 c;
+
+ old_fs = get_fs();
+ set_fs(KERNEL_DS);
+ pagefault_disable();
+
+ do {
+ ret = __copy_from_user_inatomic(&c, (u8 *)addr + len, 1);
+ len++;
+ } while (c && ret == 0 && len < MAX_STRING_SIZE);
+
+ pagefault_enable();
+ set_fs(old_fs);
+
+ if (ret < 0) /* Failed to check the length */
+ *(u32 *)dest = 0;
+ else
+ *(u32 *)dest = len;
+}
+NOKPROBE_SYMBOL(FETCH_FUNC_NAME(memory, string_size));
+
+#define DEFINE_FETCH_symbol(type) \
+void FETCH_FUNC_NAME(symbol, type)(struct pt_regs *regs, void *data, void *dest)\
+{ \
+ struct symbol_cache *sc = data; \
+ if (sc->addr) \
+ fetch_memory_##type(regs, (void *)sc->addr, dest); \
+ else \
+ *(type *)dest = 0; \
+} \
+NOKPROBE_SYMBOL(FETCH_FUNC_NAME(symbol, type));
+
+DEFINE_BASIC_FETCH_FUNCS(symbol)
+DEFINE_FETCH_symbol(string)
+DEFINE_FETCH_symbol(string_size)
+
+/* kprobes don't support file_offset fetch methods */
+#define fetch_file_offset_u8 NULL
+#define fetch_file_offset_u16 NULL
+#define fetch_file_offset_u32 NULL
+#define fetch_file_offset_u64 NULL
+#define fetch_file_offset_string NULL
+#define fetch_file_offset_string_size NULL
+
+/* Fetch type information table */
+static const struct fetch_type kprobes_fetch_type_table[] = {
+ /* Special types */
+ [FETCH_TYPE_STRING] = __ASSIGN_FETCH_TYPE("string", string, string,
+ sizeof(u32), 1, "__data_loc char[]"),
+ [FETCH_TYPE_STRSIZE] = __ASSIGN_FETCH_TYPE("string_size", u32,
+ string_size, sizeof(u32), 0, "u32"),
+ /* Basic types */
+ ASSIGN_FETCH_TYPE(u8, u8, 0),
+ ASSIGN_FETCH_TYPE(u16, u16, 0),
+ ASSIGN_FETCH_TYPE(u32, u32, 0),
+ ASSIGN_FETCH_TYPE(u64, u64, 0),
+ ASSIGN_FETCH_TYPE(s8, u8, 1),
+ ASSIGN_FETCH_TYPE(s16, u16, 1),
+ ASSIGN_FETCH_TYPE(s32, u32, 1),
+ ASSIGN_FETCH_TYPE(s64, u64, 1),
+
+ ASSIGN_FETCH_TYPE_END
+};
+
+/*
+ * Allocate new trace_probe and initialize it (including kprobes).
+ */
+static struct trace_kprobe *alloc_trace_kprobe(const char *group,
+ const char *event,
+ void *addr,
+ const char *symbol,
+ unsigned long offs,
+ int nargs, bool is_return)
+{
+ struct trace_kprobe *tk;
+ int ret = -ENOMEM;
+
+ tk = kzalloc(SIZEOF_TRACE_KPROBE(nargs), GFP_KERNEL);
+ if (!tk)
+ return ERR_PTR(ret);
+
+ if (symbol) {
+ tk->symbol = kstrdup(symbol, GFP_KERNEL);
+ if (!tk->symbol)
+ goto error;
+ tk->rp.kp.symbol_name = tk->symbol;
+ tk->rp.kp.offset = offs;
+ } else
+ tk->rp.kp.addr = addr;
+
+ if (is_return)
+ tk->rp.handler = kretprobe_dispatcher;
+ else
+ tk->rp.kp.pre_handler = kprobe_dispatcher;
+
+ if (!event || !is_good_name(event)) {
+ ret = -EINVAL;
+ goto error;
+ }
+
+ tk->tp.call.class = &tk->tp.class;
+ tk->tp.call.name = kstrdup(event, GFP_KERNEL);
+ if (!tk->tp.call.name)
+ goto error;
+
+ if (!group || !is_good_name(group)) {
+ ret = -EINVAL;
+ goto error;
+ }
+
+ tk->tp.class.system = kstrdup(group, GFP_KERNEL);
+ if (!tk->tp.class.system)
+ goto error;
+
+ INIT_LIST_HEAD(&tk->list);
+ INIT_LIST_HEAD(&tk->tp.files);
+ return tk;
+error:
+ kfree(tk->tp.call.name);
+ kfree(tk->symbol);
+ kfree(tk);
+ return ERR_PTR(ret);
+}
+
+static void free_trace_kprobe(struct trace_kprobe *tk)
+{
+ int i;
+
+ for (i = 0; i < tk->tp.nr_args; i++)
+ traceprobe_free_probe_arg(&tk->tp.args[i]);
+
+ kfree(tk->tp.call.class->system);
+ kfree(tk->tp.call.name);
+ kfree(tk->symbol);
+ kfree(tk);
+}
+
+static struct trace_kprobe *find_trace_kprobe(const char *event,
+ const char *group)
+{
+ struct trace_kprobe *tk;
+
+ list_for_each_entry(tk, &probe_list, list)
+ if (strcmp(ftrace_event_name(&tk->tp.call), event) == 0 &&
+ strcmp(tk->tp.call.class->system, group) == 0)
+ return tk;
+ return NULL;
+}
+
+/*
+ * Enable trace_probe
+ * if the file is NULL, enable "perf" handler, or enable "trace" handler.
+ */
+static int
+enable_trace_kprobe(struct trace_kprobe *tk, struct ftrace_event_file *file)
+{
+ int ret = 0;
+
+ if (file) {
+ struct event_file_link *link;
+
+ link = kmalloc(sizeof(*link), GFP_KERNEL);
+ if (!link) {
+ ret = -ENOMEM;
+ goto out;
+ }
+
+ link->file = file;
+ list_add_tail_rcu(&link->list, &tk->tp.files);
+
+ tk->tp.flags |= TP_FLAG_TRACE;
+ } else
+ tk->tp.flags |= TP_FLAG_PROFILE;
+
+ if (trace_probe_is_registered(&tk->tp) && !trace_kprobe_has_gone(tk)) {
+ if (trace_kprobe_is_return(tk))
+ ret = enable_kretprobe(&tk->rp);
+ else
+ ret = enable_kprobe(&tk->rp.kp);
+ }
+ out:
+ return ret;
+}
+
+/*
+ * Disable trace_probe
+ * if the file is NULL, disable "perf" handler, or disable "trace" handler.
+ */
+static int
+disable_trace_kprobe(struct trace_kprobe *tk, struct ftrace_event_file *file)
+{
+ struct event_file_link *link = NULL;
+ int wait = 0;
+ int ret = 0;
+
+ if (file) {
+ link = find_event_file_link(&tk->tp, file);
+ if (!link) {
+ ret = -EINVAL;
+ goto out;
+ }
+
+ list_del_rcu(&link->list);
+ wait = 1;
+ if (!list_empty(&tk->tp.files))
+ goto out;
+
+ tk->tp.flags &= ~TP_FLAG_TRACE;
+ } else
+ tk->tp.flags &= ~TP_FLAG_PROFILE;
+
+ if (!trace_probe_is_enabled(&tk->tp) && trace_probe_is_registered(&tk->tp)) {
+ if (trace_kprobe_is_return(tk))
+ disable_kretprobe(&tk->rp);
+ else
+ disable_kprobe(&tk->rp.kp);
+ wait = 1;
+ }
+ out:
+ if (wait) {
+ /*
+ * Synchronize with kprobe_trace_func/kretprobe_trace_func
+ * to ensure disabled (all running handlers are finished).
+ * This is not only for kfree(), but also the caller,
+ * trace_remove_event_call() supposes it for releasing
+ * event_call related objects, which will be accessed in
+ * the kprobe_trace_func/kretprobe_trace_func.
+ */
+ synchronize_sched();
+ kfree(link); /* Ignored if link == NULL */
+ }
+
+ return ret;
+}
+
+/* Internal register function - just handle k*probes and flags */
+static int __register_trace_kprobe(struct trace_kprobe *tk)
+{
+ int i, ret;
+
+ if (trace_probe_is_registered(&tk->tp))
+ return -EINVAL;
+
+ for (i = 0; i < tk->tp.nr_args; i++)
+ traceprobe_update_arg(&tk->tp.args[i]);
+
+ /* Set/clear disabled flag according to tp->flag */
+ if (trace_probe_is_enabled(&tk->tp))
+ tk->rp.kp.flags &= ~KPROBE_FLAG_DISABLED;
+ else
+ tk->rp.kp.flags |= KPROBE_FLAG_DISABLED;
+
+ if (trace_kprobe_is_return(tk))
+ ret = register_kretprobe(&tk->rp);
+ else
+ ret = register_kprobe(&tk->rp.kp);
+
+ if (ret == 0)
+ tk->tp.flags |= TP_FLAG_REGISTERED;
+ else {
+ pr_warning("Could not insert probe at %s+%lu: %d\n",
+ trace_kprobe_symbol(tk), trace_kprobe_offset(tk), ret);
+ if (ret == -ENOENT && trace_kprobe_is_on_module(tk)) {
+ pr_warning("This probe might be able to register after"
+ "target module is loaded. Continue.\n");
+ ret = 0;
+ } else if (ret == -EILSEQ) {
+ pr_warning("Probing address(0x%p) is not an "
+ "instruction boundary.\n",
+ tk->rp.kp.addr);
+ ret = -EINVAL;
+ }
+ }
+
+ return ret;
+}
+
+/* Internal unregister function - just handle k*probes and flags */
+static void __unregister_trace_kprobe(struct trace_kprobe *tk)
+{
+ if (trace_probe_is_registered(&tk->tp)) {
+ if (trace_kprobe_is_return(tk))
+ unregister_kretprobe(&tk->rp);
+ else
+ unregister_kprobe(&tk->rp.kp);
+ tk->tp.flags &= ~TP_FLAG_REGISTERED;
+ /* Cleanup kprobe for reuse */
+ if (tk->rp.kp.symbol_name)
+ tk->rp.kp.addr = NULL;
+ }
+}
+
+/* Unregister a trace_probe and probe_event: call with locking probe_lock */
+static int unregister_trace_kprobe(struct trace_kprobe *tk)
+{
+ /* Enabled event can not be unregistered */
+ if (trace_probe_is_enabled(&tk->tp))
+ return -EBUSY;
+
+ /* Will fail if probe is being used by ftrace or perf */
+ if (unregister_kprobe_event(tk))
+ return -EBUSY;
+
+ __unregister_trace_kprobe(tk);
+ list_del(&tk->list);
+
+ return 0;
+}
+
+/* Register a trace_probe and probe_event */
+static int register_trace_kprobe(struct trace_kprobe *tk)
+{
+ struct trace_kprobe *old_tk;
+ int ret;
+
+ mutex_lock(&probe_lock);
+
+ /* Delete old (same name) event if exist */
+ old_tk = find_trace_kprobe(ftrace_event_name(&tk->tp.call),
+ tk->tp.call.class->system);
+ if (old_tk) {
+ ret = unregister_trace_kprobe(old_tk);
+ if (ret < 0)
+ goto end;
+ free_trace_kprobe(old_tk);
+ }
+
+ /* Register new event */
+ ret = register_kprobe_event(tk);
+ if (ret) {
+ pr_warning("Failed to register probe event(%d)\n", ret);
+ goto end;
+ }
+
+ /* Register k*probe */
+ ret = __register_trace_kprobe(tk);
+ if (ret < 0)
+ unregister_kprobe_event(tk);
+ else
+ list_add_tail(&tk->list, &probe_list);
+
+end:
+ mutex_unlock(&probe_lock);
+ return ret;
+}
+
+/* Module notifier call back, checking event on the module */
+static int trace_kprobe_module_callback(struct notifier_block *nb,
+ unsigned long val, void *data)
+{
+ struct module *mod = data;
+ struct trace_kprobe *tk;
+ int ret;
+
+ if (val != MODULE_STATE_COMING)
+ return NOTIFY_DONE;
+
+ /* Update probes on coming module */
+ mutex_lock(&probe_lock);
+ list_for_each_entry(tk, &probe_list, list) {
+ if (trace_kprobe_within_module(tk, mod)) {
+ /* Don't need to check busy - this should have gone. */
+ __unregister_trace_kprobe(tk);
+ ret = __register_trace_kprobe(tk);
+ if (ret)
+ pr_warning("Failed to re-register probe %s on"
+ "%s: %d\n",
+ ftrace_event_name(&tk->tp.call),
+ mod->name, ret);
+ }
+ }
+ mutex_unlock(&probe_lock);
+
+ return NOTIFY_DONE;
+}
+
+static struct notifier_block trace_kprobe_module_nb = {
+ .notifier_call = trace_kprobe_module_callback,
+ .priority = 1 /* Invoked after kprobe module callback */
+};
+
+static int create_trace_kprobe(int argc, char **argv)
+{
+ /*
+ * Argument syntax:
+ * - Add kprobe: p[:[GRP/]EVENT] [MOD:]KSYM[+OFFS]|KADDR [FETCHARGS]
+ * - Add kretprobe: r[:[GRP/]EVENT] [MOD:]KSYM[+0] [FETCHARGS]
+ * Fetch args:
+ * $retval : fetch return value
+ * $stack : fetch stack address
+ * $stackN : fetch Nth of stack (N:0-)
+ * @ADDR : fetch memory at ADDR (ADDR should be in kernel)
+ * @SYM[+|-offs] : fetch memory at SYM +|- offs (SYM is a data symbol)
+ * %REG : fetch register REG
+ * Dereferencing memory fetch:
+ * +|-offs(ARG) : fetch memory at ARG +|- offs address.
+ * Alias name of args:
+ * NAME=FETCHARG : set NAME as alias of FETCHARG.
+ * Type of args:
+ * FETCHARG:TYPE : use TYPE instead of unsigned long.
+ */
+ struct trace_kprobe *tk;
+ int i, ret = 0;
+ bool is_return = false, is_delete = false;
+ char *symbol = NULL, *event = NULL, *group = NULL;
+ char *arg;
+ unsigned long offset = 0;
+ void *addr = NULL;
+ char buf[MAX_EVENT_NAME_LEN];
+
+ /* argc must be >= 1 */
+ if (argv[0][0] == 'p')
+ is_return = false;
+ else if (argv[0][0] == 'r')
+ is_return = true;
+ else if (argv[0][0] == '-')
+ is_delete = true;
+ else {
+ pr_info("Probe definition must be started with 'p', 'r' or"
+ " '-'.\n");
+ return -EINVAL;
+ }
+
+ if (argv[0][1] == ':') {
+ event = &argv[0][2];
+ if (strchr(event, '/')) {
+ group = event;
+ event = strchr(group, '/') + 1;
+ event[-1] = '\0';
+ if (strlen(group) == 0) {
+ pr_info("Group name is not specified\n");
+ return -EINVAL;
+ }
+ }
+ if (strlen(event) == 0) {
+ pr_info("Event name is not specified\n");
+ return -EINVAL;
+ }
+ }
+ if (!group)
+ group = KPROBE_EVENT_SYSTEM;
+
+ if (is_delete) {
+ if (!event) {
+ pr_info("Delete command needs an event name.\n");
+ return -EINVAL;
+ }
+ mutex_lock(&probe_lock);
+ tk = find_trace_kprobe(event, group);
+ if (!tk) {
+ mutex_unlock(&probe_lock);
+ pr_info("Event %s/%s doesn't exist.\n", group, event);
+ return -ENOENT;
+ }
+ /* delete an event */
+ ret = unregister_trace_kprobe(tk);
+ if (ret == 0)
+ free_trace_kprobe(tk);
+ mutex_unlock(&probe_lock);
+ return ret;
+ }
+
+ if (argc < 2) {
+ pr_info("Probe point is not specified.\n");
+ return -EINVAL;
+ }
+ if (isdigit(argv[1][0])) {
+ if (is_return) {
+ pr_info("Return probe point must be a symbol.\n");
+ return -EINVAL;
+ }
+ /* an address specified */
+ ret = kstrtoul(&argv[1][0], 0, (unsigned long *)&addr);
+ if (ret) {
+ pr_info("Failed to parse address.\n");
+ return ret;
+ }
+ } else {
+ /* a symbol specified */
+ symbol = argv[1];
+ /* TODO: support .init module functions */
+ ret = traceprobe_split_symbol_offset(symbol, &offset);
+ if (ret) {
+ pr_info("Failed to parse symbol.\n");
+ return ret;
+ }
+ if (offset && is_return) {
+ pr_info("Return probe must be used without offset.\n");
+ return -EINVAL;
+ }
+ }
+ argc -= 2; argv += 2;
+
+ /* setup a probe */
+ if (!event) {
+ /* Make a new event name */
+ if (symbol)
+ snprintf(buf, MAX_EVENT_NAME_LEN, "%c_%s_%ld",
+ is_return ? 'r' : 'p', symbol, offset);
+ else
+ snprintf(buf, MAX_EVENT_NAME_LEN, "%c_0x%p",
+ is_return ? 'r' : 'p', addr);
+ event = buf;
+ }
+ tk = alloc_trace_kprobe(group, event, addr, symbol, offset, argc,
+ is_return);
+ if (IS_ERR(tk)) {
+ pr_info("Failed to allocate trace_probe.(%d)\n",
+ (int)PTR_ERR(tk));
+ return PTR_ERR(tk);
+ }
+
+ /* parse arguments */
+ ret = 0;
+ for (i = 0; i < argc && i < MAX_TRACE_ARGS; i++) {
+ struct probe_arg *parg = &tk->tp.args[i];
+
+ /* Increment count for freeing args in error case */
+ tk->tp.nr_args++;
+
+ /* Parse argument name */
+ arg = strchr(argv[i], '=');
+ if (arg) {
+ *arg++ = '\0';
+ parg->name = kstrdup(argv[i], GFP_KERNEL);
+ } else {
+ arg = argv[i];
+ /* If argument name is omitted, set "argN" */
+ snprintf(buf, MAX_EVENT_NAME_LEN, "arg%d", i + 1);
+ parg->name = kstrdup(buf, GFP_KERNEL);
+ }
+
+ if (!parg->name) {
+ pr_info("Failed to allocate argument[%d] name.\n", i);
+ ret = -ENOMEM;
+ goto error;
+ }
+
+ if (!is_good_name(parg->name)) {
+ pr_info("Invalid argument[%d] name: %s\n",
+ i, parg->name);
+ ret = -EINVAL;
+ goto error;
+ }
+
+ if (traceprobe_conflict_field_name(parg->name,
+ tk->tp.args, i)) {
+ pr_info("Argument[%d] name '%s' conflicts with "
+ "another field.\n", i, argv[i]);
+ ret = -EINVAL;
+ goto error;
+ }
+
+ /* Parse fetch argument */
+ ret = traceprobe_parse_probe_arg(arg, &tk->tp.size, parg,
+ is_return, true,
+ kprobes_fetch_type_table);
+ if (ret) {
+ pr_info("Parse error at argument[%d]. (%d)\n", i, ret);
+ goto error;
+ }
+ }
+
+ ret = register_trace_kprobe(tk);
+ if (ret)
+ goto error;
+ return 0;
+
+error:
+ free_trace_kprobe(tk);
+ return ret;
+}
+
+static int release_all_trace_kprobes(void)
+{
+ struct trace_kprobe *tk;
+ int ret = 0;
+
+ mutex_lock(&probe_lock);
+ /* Ensure no probe is in use. */
+ list_for_each_entry(tk, &probe_list, list)
+ if (trace_probe_is_enabled(&tk->tp)) {
+ ret = -EBUSY;
+ goto end;
+ }
+ /* TODO: Use batch unregistration */
+ while (!list_empty(&probe_list)) {
+ tk = list_entry(probe_list.next, struct trace_kprobe, list);
+ ret = unregister_trace_kprobe(tk);
+ if (ret)
+ goto end;
+ free_trace_kprobe(tk);
+ }
+
+end:
+ mutex_unlock(&probe_lock);
+
+ return ret;
+}
+
+/* Probes listing interfaces */
+static void *probes_seq_start(struct seq_file *m, loff_t *pos)
+{
+ mutex_lock(&probe_lock);
+ return seq_list_start(&probe_list, *pos);
+}
+
+static void *probes_seq_next(struct seq_file *m, void *v, loff_t *pos)
+{
+ return seq_list_next(v, &probe_list, pos);
+}
+
+static void probes_seq_stop(struct seq_file *m, void *v)
+{
+ mutex_unlock(&probe_lock);
+}
+
+static int probes_seq_show(struct seq_file *m, void *v)
+{
+ struct trace_kprobe *tk = v;
+ int i;
+
+ seq_putc(m, trace_kprobe_is_return(tk) ? 'r' : 'p');
+ seq_printf(m, ":%s/%s", tk->tp.call.class->system,
+ ftrace_event_name(&tk->tp.call));
+
+ if (!tk->symbol)
+ seq_printf(m, " 0x%p", tk->rp.kp.addr);
+ else if (tk->rp.kp.offset)
+ seq_printf(m, " %s+%u", trace_kprobe_symbol(tk),
+ tk->rp.kp.offset);
+ else
+ seq_printf(m, " %s", trace_kprobe_symbol(tk));
+
+ for (i = 0; i < tk->tp.nr_args; i++)
+ seq_printf(m, " %s=%s", tk->tp.args[i].name, tk->tp.args[i].comm);
+ seq_putc(m, '\n');
+
+ return 0;
+}
+
+static const struct seq_operations probes_seq_op = {
+ .start = probes_seq_start,
+ .next = probes_seq_next,
+ .stop = probes_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 = release_all_trace_kprobes();
+ if (ret < 0)
+ 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 traceprobe_probes_write(file, buffer, count, ppos,
+ create_trace_kprobe);
+}
+
+static const struct file_operations kprobe_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 trace_kprobe *tk = v;
+
+ seq_printf(m, " %-44s %15lu %15lu\n",
+ ftrace_event_name(&tk->tp.call), tk->nhit,
+ tk->rp.kp.nmissed);
+
+ return 0;
+}
+
+static const struct seq_operations profile_seq_op = {
+ .start = probes_seq_start,
+ .next = probes_seq_next,
+ .stop = probes_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 kprobe_profile_ops = {
+ .owner = THIS_MODULE,
+ .open = profile_open,
+ .read = seq_read,
+ .llseek = seq_lseek,
+ .release = seq_release,
+};
+
+/* Kprobe handler */
+static nokprobe_inline void
+__kprobe_trace_func(struct trace_kprobe *tk, struct pt_regs *regs,
+ struct ftrace_event_file *ftrace_file)
+{
+ struct kprobe_trace_entry_head *entry;
+ struct ring_buffer_event *event;
+ struct ring_buffer *buffer;
+ int size, dsize, pc;
+ unsigned long irq_flags;
+ struct ftrace_event_call *call = &tk->tp.call;
+
+ WARN_ON(call != ftrace_file->event_call);
+
+ if (ftrace_trigger_soft_disabled(ftrace_file))
+ return;
+
+ local_save_flags(irq_flags);
+ pc = preempt_count();
+
+ dsize = __get_data_size(&tk->tp, regs);
+ size = sizeof(*entry) + tk->tp.size + dsize;
+
+ event = trace_event_buffer_lock_reserve(&buffer, ftrace_file,
+ call->event.type,
+ size, irq_flags, pc);
+ if (!event)
+ return;
+
+ entry = ring_buffer_event_data(event);
+ entry->ip = (unsigned long)tk->rp.kp.addr;
+ store_trace_args(sizeof(*entry), &tk->tp, regs, (u8 *)&entry[1], dsize);
+
+ event_trigger_unlock_commit_regs(ftrace_file, buffer, event,
+ entry, irq_flags, pc, regs);
+}
+
+static void
+kprobe_trace_func(struct trace_kprobe *tk, struct pt_regs *regs)
+{
+ struct event_file_link *link;
+
+ list_for_each_entry_rcu(link, &tk->tp.files, list)
+ __kprobe_trace_func(tk, regs, link->file);
+}
+NOKPROBE_SYMBOL(kprobe_trace_func);
+
+/* Kretprobe handler */
+static nokprobe_inline void
+__kretprobe_trace_func(struct trace_kprobe *tk, struct kretprobe_instance *ri,
+ struct pt_regs *regs,
+ struct ftrace_event_file *ftrace_file)
+{
+ struct kretprobe_trace_entry_head *entry;
+ struct ring_buffer_event *event;
+ struct ring_buffer *buffer;
+ int size, pc, dsize;
+ unsigned long irq_flags;
+ struct ftrace_event_call *call = &tk->tp.call;
+
+ WARN_ON(call != ftrace_file->event_call);
+
+ if (ftrace_trigger_soft_disabled(ftrace_file))
+ return;
+
+ local_save_flags(irq_flags);
+ pc = preempt_count();
+
+ dsize = __get_data_size(&tk->tp, regs);
+ size = sizeof(*entry) + tk->tp.size + dsize;
+
+ event = trace_event_buffer_lock_reserve(&buffer, ftrace_file,
+ call->event.type,
+ size, irq_flags, pc);
+ if (!event)
+ return;
+
+ entry = ring_buffer_event_data(event);
+ entry->func = (unsigned long)tk->rp.kp.addr;
+ entry->ret_ip = (unsigned long)ri->ret_addr;
+ store_trace_args(sizeof(*entry), &tk->tp, regs, (u8 *)&entry[1], dsize);
+
+ event_trigger_unlock_commit_regs(ftrace_file, buffer, event,
+ entry, irq_flags, pc, regs);
+}
+
+static void
+kretprobe_trace_func(struct trace_kprobe *tk, struct kretprobe_instance *ri,
+ struct pt_regs *regs)
+{
+ struct event_file_link *link;
+
+ list_for_each_entry_rcu(link, &tk->tp.files, list)
+ __kretprobe_trace_func(tk, ri, regs, link->file);
+}
+NOKPROBE_SYMBOL(kretprobe_trace_func);
+
+/* Event entry printers */
+static enum print_line_t
+print_kprobe_event(struct trace_iterator *iter, int flags,
+ struct trace_event *event)
+{
+ struct kprobe_trace_entry_head *field;
+ struct trace_seq *s = &iter->seq;
+ struct trace_probe *tp;
+ u8 *data;
+ int i;
+
+ field = (struct kprobe_trace_entry_head *)iter->ent;
+ tp = container_of(event, struct trace_probe, call.event);
+
+ trace_seq_printf(s, "%s: (", ftrace_event_name(&tp->call));
+
+ if (!seq_print_ip_sym(s, field->ip, flags | TRACE_ITER_SYM_OFFSET))
+ goto out;
+
+ trace_seq_putc(s, ')');
+
+ data = (u8 *)&field[1];
+ for (i = 0; i < tp->nr_args; i++)
+ if (!tp->args[i].type->print(s, tp->args[i].name,
+ data + tp->args[i].offset, field))
+ goto out;
+
+ trace_seq_putc(s, '\n');
+ out:
+ return trace_handle_return(s);
+}
+
+static enum print_line_t
+print_kretprobe_event(struct trace_iterator *iter, int flags,
+ struct trace_event *event)
+{
+ struct kretprobe_trace_entry_head *field;
+ struct trace_seq *s = &iter->seq;
+ struct trace_probe *tp;
+ u8 *data;
+ int i;
+
+ field = (struct kretprobe_trace_entry_head *)iter->ent;
+ tp = container_of(event, struct trace_probe, call.event);
+
+ trace_seq_printf(s, "%s: (", ftrace_event_name(&tp->call));
+
+ if (!seq_print_ip_sym(s, field->ret_ip, flags | TRACE_ITER_SYM_OFFSET))
+ goto out;
+
+ trace_seq_puts(s, " <- ");
+
+ if (!seq_print_ip_sym(s, field->func, flags & ~TRACE_ITER_SYM_OFFSET))
+ goto out;
+
+ trace_seq_putc(s, ')');
+
+ data = (u8 *)&field[1];
+ for (i = 0; i < tp->nr_args; i++)
+ if (!tp->args[i].type->print(s, tp->args[i].name,
+ data + tp->args[i].offset, field))
+ goto out;
+
+ trace_seq_putc(s, '\n');
+
+ out:
+ return trace_handle_return(s);
+}
+
+
+static int kprobe_event_define_fields(struct ftrace_event_call *event_call)
+{
+ int ret, i;
+ struct kprobe_trace_entry_head field;
+ struct trace_kprobe *tk = (struct trace_kprobe *)event_call->data;
+
+ DEFINE_FIELD(unsigned long, ip, FIELD_STRING_IP, 0);
+ /* Set argument names as fields */
+ for (i = 0; i < tk->tp.nr_args; i++) {
+ struct probe_arg *parg = &tk->tp.args[i];
+
+ ret = trace_define_field(event_call, parg->type->fmttype,
+ parg->name,
+ sizeof(field) + parg->offset,
+ parg->type->size,
+ parg->type->is_signed,
+ FILTER_OTHER);
+ if (ret)
+ return ret;
+ }
+ return 0;
+}
+
+static int kretprobe_event_define_fields(struct ftrace_event_call *event_call)
+{
+ int ret, i;
+ struct kretprobe_trace_entry_head field;
+ struct trace_kprobe *tk = (struct trace_kprobe *)event_call->data;
+
+ DEFINE_FIELD(unsigned long, func, FIELD_STRING_FUNC, 0);
+ DEFINE_FIELD(unsigned long, ret_ip, FIELD_STRING_RETIP, 0);
+ /* Set argument names as fields */
+ for (i = 0; i < tk->tp.nr_args; i++) {
+ struct probe_arg *parg = &tk->tp.args[i];
+
+ ret = trace_define_field(event_call, parg->type->fmttype,
+ parg->name,
+ sizeof(field) + parg->offset,
+ parg->type->size,
+ parg->type->is_signed,
+ FILTER_OTHER);
+ if (ret)
+ return ret;
+ }
+ return 0;
+}
+
+#ifdef CONFIG_PERF_EVENTS
+
+/* Kprobe profile handler */
+static void
+kprobe_perf_func(struct trace_kprobe *tk, struct pt_regs *regs)
+{
+ struct ftrace_event_call *call = &tk->tp.call;
+ struct bpf_prog *prog = call->prog;
+ struct kprobe_trace_entry_head *entry;
+ struct hlist_head *head;
+ int size, __size, dsize;
+ int rctx;
+
+ if (prog && !trace_call_bpf(prog, regs))
+ return;
+
+ head = this_cpu_ptr(call->perf_events);
+ if (hlist_empty(head))
+ return;
+
+ dsize = __get_data_size(&tk->tp, regs);
+ __size = sizeof(*entry) + tk->tp.size + dsize;
+ size = ALIGN(__size + sizeof(u32), sizeof(u64));
+ size -= sizeof(u32);
+
+ entry = perf_trace_buf_prepare(size, call->event.type, NULL, &rctx);
+ if (!entry)
+ return;
+
+ entry->ip = (unsigned long)tk->rp.kp.addr;
+ memset(&entry[1], 0, dsize);
+ store_trace_args(sizeof(*entry), &tk->tp, regs, (u8 *)&entry[1], dsize);
+ perf_trace_buf_submit(entry, size, rctx, 0, 1, regs, head, NULL);
+}
+NOKPROBE_SYMBOL(kprobe_perf_func);
+
+/* Kretprobe profile handler */
+static void
+kretprobe_perf_func(struct trace_kprobe *tk, struct kretprobe_instance *ri,
+ struct pt_regs *regs)
+{
+ struct ftrace_event_call *call = &tk->tp.call;
+ struct bpf_prog *prog = call->prog;
+ struct kretprobe_trace_entry_head *entry;
+ struct hlist_head *head;
+ int size, __size, dsize;
+ int rctx;
+
+ if (prog && !trace_call_bpf(prog, regs))
+ return;
+
+ head = this_cpu_ptr(call->perf_events);
+ if (hlist_empty(head))
+ return;
+
+ dsize = __get_data_size(&tk->tp, regs);
+ __size = sizeof(*entry) + tk->tp.size + dsize;
+ size = ALIGN(__size + sizeof(u32), sizeof(u64));
+ size -= sizeof(u32);
+
+ entry = perf_trace_buf_prepare(size, call->event.type, NULL, &rctx);
+ if (!entry)
+ return;
+
+ entry->func = (unsigned long)tk->rp.kp.addr;
+ entry->ret_ip = (unsigned long)ri->ret_addr;
+ store_trace_args(sizeof(*entry), &tk->tp, regs, (u8 *)&entry[1], dsize);
+ perf_trace_buf_submit(entry, size, rctx, 0, 1, regs, head, NULL);
+}
+NOKPROBE_SYMBOL(kretprobe_perf_func);
+#endif /* CONFIG_PERF_EVENTS */
+
+/*
+ * called by perf_trace_init() or __ftrace_set_clr_event() under event_mutex.
+ *
+ * kprobe_trace_self_tests_init() does enable_trace_probe/disable_trace_probe
+ * lockless, but we can't race with this __init function.
+ */
+static int kprobe_register(struct ftrace_event_call *event,
+ enum trace_reg type, void *data)
+{
+ struct trace_kprobe *tk = (struct trace_kprobe *)event->data;
+ struct ftrace_event_file *file = data;
+
+ switch (type) {
+ case TRACE_REG_REGISTER:
+ return enable_trace_kprobe(tk, file);
+ case TRACE_REG_UNREGISTER:
+ return disable_trace_kprobe(tk, file);
+
+#ifdef CONFIG_PERF_EVENTS
+ case TRACE_REG_PERF_REGISTER:
+ return enable_trace_kprobe(tk, NULL);
+ case TRACE_REG_PERF_UNREGISTER:
+ return disable_trace_kprobe(tk, NULL);
+ case TRACE_REG_PERF_OPEN:
+ case TRACE_REG_PERF_CLOSE:
+ case TRACE_REG_PERF_ADD:
+ case TRACE_REG_PERF_DEL:
+ return 0;
+#endif
+ }
+ return 0;
+}
+
+static int kprobe_dispatcher(struct kprobe *kp, struct pt_regs *regs)
+{
+ struct trace_kprobe *tk = container_of(kp, struct trace_kprobe, rp.kp);
+
+ tk->nhit++;
+
+ if (tk->tp.flags & TP_FLAG_TRACE)
+ kprobe_trace_func(tk, regs);
+#ifdef CONFIG_PERF_EVENTS
+ if (tk->tp.flags & TP_FLAG_PROFILE)
+ kprobe_perf_func(tk, regs);
+#endif
+ return 0; /* We don't tweek kernel, so just return 0 */
+}
+NOKPROBE_SYMBOL(kprobe_dispatcher);
+
+static int
+kretprobe_dispatcher(struct kretprobe_instance *ri, struct pt_regs *regs)
+{
+ struct trace_kprobe *tk = container_of(ri->rp, struct trace_kprobe, rp);
+
+ tk->nhit++;
+
+ if (tk->tp.flags & TP_FLAG_TRACE)
+ kretprobe_trace_func(tk, ri, regs);
+#ifdef CONFIG_PERF_EVENTS
+ if (tk->tp.flags & TP_FLAG_PROFILE)
+ kretprobe_perf_func(tk, ri, regs);
+#endif
+ return 0; /* We don't tweek kernel, so just return 0 */
+}
+NOKPROBE_SYMBOL(kretprobe_dispatcher);
+
+static struct trace_event_functions kretprobe_funcs = {
+ .trace = print_kretprobe_event
+};
+
+static struct trace_event_functions kprobe_funcs = {
+ .trace = print_kprobe_event
+};
+
+static int register_kprobe_event(struct trace_kprobe *tk)
+{
+ struct ftrace_event_call *call = &tk->tp.call;
+ int ret;
+
+ /* Initialize ftrace_event_call */
+ INIT_LIST_HEAD(&call->class->fields);
+ if (trace_kprobe_is_return(tk)) {
+ call->event.funcs = &kretprobe_funcs;
+ call->class->define_fields = kretprobe_event_define_fields;
+ } else {
+ call->event.funcs = &kprobe_funcs;
+ call->class->define_fields = kprobe_event_define_fields;
+ }
+ if (set_print_fmt(&tk->tp, trace_kprobe_is_return(tk)) < 0)
+ return -ENOMEM;
+ ret = register_ftrace_event(&call->event);
+ if (!ret) {
+ kfree(call->print_fmt);
+ return -ENODEV;
+ }
+ call->flags = TRACE_EVENT_FL_KPROBE;
+ call->class->reg = kprobe_register;
+ call->data = tk;
+ ret = trace_add_event_call(call);
+ if (ret) {
+ pr_info("Failed to register kprobe event: %s\n",
+ ftrace_event_name(call));
+ kfree(call->print_fmt);
+ unregister_ftrace_event(&call->event);
+ }
+ return ret;
+}
+
+static int unregister_kprobe_event(struct trace_kprobe *tk)
+{
+ int ret;
+
+ /* tp->event is unregistered in trace_remove_event_call() */
+ ret = trace_remove_event_call(&tk->tp.call);
+ if (!ret)
+ kfree(tk->tp.call.print_fmt);
+ return ret;
+}
+
+/* Make a tracefs interface for controlling probe points */
+static __init int init_kprobe_trace(void)
+{
+ struct dentry *d_tracer;
+ struct dentry *entry;
+
+ if (register_module_notifier(&trace_kprobe_module_nb))
+ return -EINVAL;
+
+ d_tracer = tracing_init_dentry();
+ if (IS_ERR(d_tracer))
+ return 0;
+
+ entry = tracefs_create_file("kprobe_events", 0644, d_tracer,
+ NULL, &kprobe_events_ops);
+
+ /* Event list interface */
+ if (!entry)
+ pr_warning("Could not create tracefs "
+ "'kprobe_events' entry\n");
+
+ /* Profile interface */
+ entry = tracefs_create_file("kprobe_profile", 0444, d_tracer,
+ NULL, &kprobe_profile_ops);
+
+ if (!entry)
+ pr_warning("Could not create tracefs "
+ "'kprobe_profile' entry\n");
+ return 0;
+}
+fs_initcall(init_kprobe_trace);
+
+
+#ifdef CONFIG_FTRACE_STARTUP_TEST
+
+/*
+ * The "__used" keeps gcc from removing the function symbol
+ * from the kallsyms table.
+ */
+static __used int kprobe_trace_selftest_target(int a1, int a2, int a3,
+ int a4, int a5, int a6)
+{
+ return a1 + a2 + a3 + a4 + a5 + a6;
+}
+
+static struct ftrace_event_file *
+find_trace_probe_file(struct trace_kprobe *tk, struct trace_array *tr)
+{
+ struct ftrace_event_file *file;
+
+ list_for_each_entry(file, &tr->events, list)
+ if (file->event_call == &tk->tp.call)
+ return file;
+
+ return NULL;
+}
+
+/*
+ * Nobody but us can call enable_trace_kprobe/disable_trace_kprobe at this
+ * stage, we can do this lockless.
+ */
+static __init int kprobe_trace_self_tests_init(void)
+{
+ int ret, warn = 0;
+ int (*target)(int, int, int, int, int, int);
+ struct trace_kprobe *tk;
+ struct ftrace_event_file *file;
+
+ if (tracing_is_disabled())
+ return -ENODEV;
+
+ target = kprobe_trace_selftest_target;
+
+ pr_info("Testing kprobe tracing: ");
+
+ ret = traceprobe_command("p:testprobe kprobe_trace_selftest_target "
+ "$stack $stack0 +0($stack)",
+ create_trace_kprobe);
+ if (WARN_ON_ONCE(ret)) {
+ pr_warn("error on probing function entry.\n");
+ warn++;
+ } else {
+ /* Enable trace point */
+ tk = find_trace_kprobe("testprobe", KPROBE_EVENT_SYSTEM);
+ if (WARN_ON_ONCE(tk == NULL)) {
+ pr_warn("error on getting new probe.\n");
+ warn++;
+ } else {
+ file = find_trace_probe_file(tk, top_trace_array());
+ if (WARN_ON_ONCE(file == NULL)) {
+ pr_warn("error on getting probe file.\n");
+ warn++;
+ } else
+ enable_trace_kprobe(tk, file);
+ }
+ }
+
+ ret = traceprobe_command("r:testprobe2 kprobe_trace_selftest_target "
+ "$retval", create_trace_kprobe);
+ if (WARN_ON_ONCE(ret)) {
+ pr_warn("error on probing function return.\n");
+ warn++;
+ } else {
+ /* Enable trace point */
+ tk = find_trace_kprobe("testprobe2", KPROBE_EVENT_SYSTEM);
+ if (WARN_ON_ONCE(tk == NULL)) {
+ pr_warn("error on getting 2nd new probe.\n");
+ warn++;
+ } else {
+ file = find_trace_probe_file(tk, top_trace_array());
+ if (WARN_ON_ONCE(file == NULL)) {
+ pr_warn("error on getting probe file.\n");
+ warn++;
+ } else
+ enable_trace_kprobe(tk, file);
+ }
+ }
+
+ if (warn)
+ goto end;
+
+ ret = target(1, 2, 3, 4, 5, 6);
+
+ /* Disable trace points before removing it */
+ tk = find_trace_kprobe("testprobe", KPROBE_EVENT_SYSTEM);
+ if (WARN_ON_ONCE(tk == NULL)) {
+ pr_warn("error on getting test probe.\n");
+ warn++;
+ } else {
+ file = find_trace_probe_file(tk, top_trace_array());
+ if (WARN_ON_ONCE(file == NULL)) {
+ pr_warn("error on getting probe file.\n");
+ warn++;
+ } else
+ disable_trace_kprobe(tk, file);
+ }
+
+ tk = find_trace_kprobe("testprobe2", KPROBE_EVENT_SYSTEM);
+ if (WARN_ON_ONCE(tk == NULL)) {
+ pr_warn("error on getting 2nd test probe.\n");
+ warn++;
+ } else {
+ file = find_trace_probe_file(tk, top_trace_array());
+ if (WARN_ON_ONCE(file == NULL)) {
+ pr_warn("error on getting probe file.\n");
+ warn++;
+ } else
+ disable_trace_kprobe(tk, file);
+ }
+
+ ret = traceprobe_command("-:testprobe", create_trace_kprobe);
+ if (WARN_ON_ONCE(ret)) {
+ pr_warn("error on deleting a probe.\n");
+ warn++;
+ }
+
+ ret = traceprobe_command("-:testprobe2", create_trace_kprobe);
+ if (WARN_ON_ONCE(ret)) {
+ pr_warn("error on deleting a probe.\n");
+ warn++;
+ }
+
+end:
+ release_all_trace_kprobes();
+ if (warn)
+ pr_cont("NG: Some tests are failed. Please check them.\n");
+ else
+ pr_cont("OK\n");
+ return 0;
+}
+
+late_initcall(kprobe_trace_self_tests_init);
+
+#endif