1 files changed, 119 insertions, 185 deletions

diff --git a/kernel/trace/trace_kprobe.c b/kernel/trace/trace_kprobe.c
index 50b1b8239806..505c92273b1a 100644
--- a/kernel/trace/trace_kprobe.c
+++ b/kernel/trace/trace_kprobe.c
@@ -91,11 +91,6 @@ static __kprobes unsigned long fetch_memory(struct pt_regs *regs, void *addr)
         return retval;
 }
 
-static __kprobes unsigned long fetch_argument(struct pt_regs *regs, void *num)
-{
-        return regs_get_argument_nth(regs, (unsigned int)((unsigned long)num));
-}
-
 static __kprobes unsigned long fetch_retvalue(struct pt_regs *regs,
                                               void *dummy)
 {
@@ -231,9 +226,7 @@ static int probe_arg_string(char *buf, size_t n, struct fetch_func *ff)
 {
         int ret = -EINVAL;
 
-        if (ff->func == fetch_argument)
-                ret = snprintf(buf, n, "$arg%lu", (unsigned long)ff->data);
-        else if (ff->func == fetch_register) {
+        if (ff->func == fetch_register) {
                 const char *name;
                 name = regs_query_register_name((unsigned int)((long)ff->data));
                 ret = snprintf(buf, n, "%%%s", name);
@@ -489,14 +482,6 @@ static int parse_probe_vars(char *arg, struct fetch_func *ff, int is_return)
                         }
                 } else
                         ret = -EINVAL;
-        } else if (strncmp(arg, "arg", 3) == 0 && isdigit(arg[3])) {
-                ret = strict_strtoul(arg + 3, 10, &param);
-                if (ret || param > PARAM_MAX_ARGS)
-                        ret = -EINVAL;
-                else {
-                        ff->func = fetch_argument;
-                        ff->data = (void *)param;
-                }
         } else
                 ret = -EINVAL;
         return ret;
@@ -611,7 +596,6 @@ static int create_trace_probe(int argc, char **argv)
          *  - Add kprobe: p[:[GRP/]EVENT] KSYM[+OFFS]|KADDR [FETCHARGS]
          *  - Add kretprobe: r[:[GRP/]EVENT] KSYM[+0] [FETCHARGS]
          * Fetch args:
-         *  $argN       : fetch Nth of function argument. (N:0-)
          *  $retval     : fetch return value
          *  $stack      : fetch stack address
          *  $stackN     : fetch Nth of stack (N:0-)
@@ -651,12 +635,12 @@ static int create_trace_probe(int argc, char **argv)
                         event = strchr(group, '/') + 1;
                         event[-1] = '\0';
                         if (strlen(group) == 0) {
-                                pr_info("Group name is not specifiled\n");
+                                pr_info("Group name is not specified\n");
                                 return -EINVAL;
                         }
                 }
                 if (strlen(event) == 0) {
-                        pr_info("Event name is not specifiled\n");
+                        pr_info("Event name is not specified\n");
                         return -EINVAL;
                 }
         }
@@ -958,7 +942,7 @@ static const struct file_operations kprobe_profile_ops = {
 };
 
 /* Kprobe handler */
-static __kprobes int kprobe_trace_func(struct kprobe *kp, struct pt_regs *regs)
+static __kprobes void kprobe_trace_func(struct kprobe *kp, struct pt_regs *regs)
 {
         struct trace_probe *tp = container_of(kp, struct trace_probe, rp.kp);
         struct kprobe_trace_entry *entry;
@@ -978,7 +962,7 @@ static __kprobes int kprobe_trace_func(struct kprobe *kp, struct pt_regs *regs)
         event = trace_current_buffer_lock_reserve(&buffer, call->id, size,
                                                   irq_flags, pc);
         if (!event)
-                return 0;
+                return;
 
         entry = ring_buffer_event_data(event);
         entry->nargs = tp->nr_args;
@@ -988,11 +972,10 @@ static __kprobes int kprobe_trace_func(struct kprobe *kp, struct pt_regs *regs)
 
         if (!filter_current_check_discard(buffer, call, entry, event))
                 trace_nowake_buffer_unlock_commit(buffer, event, irq_flags, pc);
-        return 0;
 }
 
 /* Kretprobe handler */
-static __kprobes int kretprobe_trace_func(struct kretprobe_instance *ri,
+static __kprobes void kretprobe_trace_func(struct kretprobe_instance *ri,
                                           struct pt_regs *regs)
 {
         struct trace_probe *tp = container_of(ri->rp, struct trace_probe, rp);
@@ -1011,7 +994,7 @@ static __kprobes int kretprobe_trace_func(struct kretprobe_instance *ri,
         event = trace_current_buffer_lock_reserve(&buffer, call->id, size,
                                                   irq_flags, pc);
         if (!event)
-                return 0;
+                return;
 
         entry = ring_buffer_event_data(event);
         entry->nargs = tp->nr_args;
@@ -1022,8 +1005,6 @@ static __kprobes int kretprobe_trace_func(struct kretprobe_instance *ri,
 
         if (!filter_current_check_discard(buffer, call, entry, event))
                 trace_nowake_buffer_unlock_commit(buffer, event, irq_flags, pc);
-
-        return 0;
 }
 
 /* Event entry printers */
@@ -1174,213 +1155,123 @@ static int kretprobe_event_define_fields(struct ftrace_event_call *event_call)
         return 0;
 }
 
-static int __probe_event_show_format(struct trace_seq *s,
-                                     struct trace_probe *tp, const char *fmt,
-                                     const char *arg)
+static int __set_print_fmt(struct trace_probe *tp, char *buf, int len)
 {
         int i;
+        int pos = 0;
 
-        /* Show format */
-        if (!trace_seq_printf(s, "\nprint fmt: \"%s", fmt))
-                return 0;
+        const char *fmt, *arg;
 
-        for (i = 0; i < tp->nr_args; i++)
-                if (!trace_seq_printf(s, " %s=%%lx", tp->args[i].name))
-                        return 0;
+        if (!probe_is_return(tp)) {
+                fmt = "(%lx)";
+                arg = "REC->" FIELD_STRING_IP;
+        } else {
+                fmt = "(%lx <- %lx)";
+                arg = "REC->" FIELD_STRING_FUNC ", REC->" FIELD_STRING_RETIP;
+        }
 
-        if (!trace_seq_printf(s, "\", %s", arg))
-                return 0;
+        /* When len=0, we just calculate the needed length */
+#define LEN_OR_ZERO (len ? len - pos : 0)
 
-        for (i = 0; i < tp->nr_args; i++)
-                if (!trace_seq_printf(s, ", REC->%s", tp->args[i].name))
-                        return 0;
-
-        return trace_seq_puts(s, "\n");
-}
+        pos += snprintf(buf + pos, LEN_OR_ZERO, "\"%s", fmt);
 
-#undef SHOW_FIELD
-#define SHOW_FIELD(type, item, name)                                    \
-        do {                                                            \
-                ret = trace_seq_printf(s, "\tfield:" #type " %s;\t"     \
-                                "offset:%u;\tsize:%u;\tsigned:%d;\n", name,\
-                                (unsigned int)offsetof(typeof(field), item),\
-                                (unsigned int)sizeof(type),             \
-                                is_signed_type(type));                  \
-                if (!ret)                                               \
-                        return 0;                                       \
-        } while (0)
+        for (i = 0; i < tp->nr_args; i++) {
+                pos += snprintf(buf + pos, LEN_OR_ZERO, " %s=%%lx",
+                                tp->args[i].name);
+        }
 
-static int kprobe_event_show_format(struct ftrace_event_call *call,
-                                    struct trace_seq *s)
-{
-        struct kprobe_trace_entry field __attribute__((unused));
-        int ret, i;
-        struct trace_probe *tp = (struct trace_probe *)call->data;
+        pos += snprintf(buf + pos, LEN_OR_ZERO, "\", %s", arg);
 
-        SHOW_FIELD(unsigned long, ip, FIELD_STRING_IP);
-        SHOW_FIELD(int, nargs, FIELD_STRING_NARGS);
+        for (i = 0; i < tp->nr_args; i++) {
+                pos += snprintf(buf + pos, LEN_OR_ZERO, ", REC->%s",
+                                tp->args[i].name);
+        }
 
-        /* Show fields */
-        for (i = 0; i < tp->nr_args; i++)
-                SHOW_FIELD(unsigned long, args[i], tp->args[i].name);
-        trace_seq_puts(s, "\n");
+#undef LEN_OR_ZERO
 
-        return __probe_event_show_format(s, tp, "(%lx)",
-                                         "REC->" FIELD_STRING_IP);
+        /* return the length of print_fmt */
+        return pos;
 }
 
-static int kretprobe_event_show_format(struct ftrace_event_call *call,
-                                       struct trace_seq *s)
+static int set_print_fmt(struct trace_probe *tp)
 {
-        struct kretprobe_trace_entry field __attribute__((unused));
-        int ret, i;
-        struct trace_probe *tp = (struct trace_probe *)call->data;
+        int len;
+        char *print_fmt;
 
-        SHOW_FIELD(unsigned long, func, FIELD_STRING_FUNC);
-        SHOW_FIELD(unsigned long, ret_ip, FIELD_STRING_RETIP);
-        SHOW_FIELD(int, nargs, FIELD_STRING_NARGS);
+        /* First: called with 0 length to calculate the needed length */
+        len = __set_print_fmt(tp, NULL, 0);
+        print_fmt = kmalloc(len + 1, GFP_KERNEL);
+        if (!print_fmt)
+                return -ENOMEM;
 
-        /* Show fields */
-        for (i = 0; i < tp->nr_args; i++)
-                SHOW_FIELD(unsigned long, args[i], tp->args[i].name);
-        trace_seq_puts(s, "\n");
+        /* Second: actually write the @print_fmt */
+        __set_print_fmt(tp, print_fmt, len + 1);
+        tp->call.print_fmt = print_fmt;
 
-        return __probe_event_show_format(s, tp, "(%lx <- %lx)",
-                                         "REC->" FIELD_STRING_FUNC
-                                         ", REC->" FIELD_STRING_RETIP);
+        return 0;
 }
 
-#ifdef CONFIG_EVENT_PROFILE
+#ifdef CONFIG_PERF_EVENTS
 
 /* Kprobe profile handler */
-static __kprobes int kprobe_profile_func(struct kprobe *kp,
+static __kprobes void kprobe_profile_func(struct kprobe *kp,
                                          struct pt_regs *regs)
 {
         struct trace_probe *tp = container_of(kp, struct trace_probe, rp.kp);
         struct ftrace_event_call *call = &tp->call;
         struct kprobe_trace_entry *entry;
-        struct trace_entry *ent;
-        int size, __size, i, pc, __cpu;
+        int size, __size, i;
         unsigned long irq_flags;
-        char *trace_buf;
-        char *raw_data;
         int rctx;
 
-        pc = preempt_count();
         __size = SIZEOF_KPROBE_TRACE_ENTRY(tp->nr_args);
         size = ALIGN(__size + sizeof(u32), sizeof(u64));
         size -= sizeof(u32);
         if (WARN_ONCE(size > FTRACE_MAX_PROFILE_SIZE,
                      "profile buffer not large enough"))
-                return 0;
-
-        /*
-         * Protect the non nmi buffer
-         * This also protects the rcu read side
-         */
-        local_irq_save(irq_flags);
-
-        rctx = perf_swevent_get_recursion_context();
-        if (rctx < 0)
-                goto end_recursion;
-
-        __cpu = smp_processor_id();
-
-        if (in_nmi())
-                trace_buf = rcu_dereference(perf_trace_buf_nmi);
-        else
-                trace_buf = rcu_dereference(perf_trace_buf);
+                return;
 
-        if (!trace_buf)
-                goto end;
-
-        raw_data = per_cpu_ptr(trace_buf, __cpu);
-
-        /* Zero dead bytes from alignment to avoid buffer leak to userspace */
-        *(u64 *)(&raw_data[size - sizeof(u64)]) = 0ULL;
-        entry = (struct kprobe_trace_entry *)raw_data;
-        ent = &entry->ent;
+        entry = ftrace_perf_buf_prepare(size, call->id, &rctx, &irq_flags);
+        if (!entry)
+                return;
 
-        tracing_generic_entry_update(ent, irq_flags, pc);
-        ent->type = call->id;
         entry->nargs = tp->nr_args;
         entry->ip = (unsigned long)kp->addr;
         for (i = 0; i < tp->nr_args; i++)
                 entry->args[i] = call_fetch(&tp->args[i].fetch, regs);
-        perf_tp_event(call->id, entry->ip, 1, entry, size);
-
-end:
-        perf_swevent_put_recursion_context(rctx);
-end_recursion:
-        local_irq_restore(irq_flags);
 
-        return 0;
+        ftrace_perf_buf_submit(entry, size, rctx, entry->ip, 1, irq_flags);
 }
 
 /* Kretprobe profile handler */
-static __kprobes int kretprobe_profile_func(struct kretprobe_instance *ri,
+static __kprobes void kretprobe_profile_func(struct kretprobe_instance *ri,
                                             struct pt_regs *regs)
 {
         struct trace_probe *tp = container_of(ri->rp, struct trace_probe, rp);
         struct ftrace_event_call *call = &tp->call;
         struct kretprobe_trace_entry *entry;
-        struct trace_entry *ent;
-        int size, __size, i, pc, __cpu;
+        int size, __size, i;
         unsigned long irq_flags;
-        char *trace_buf;
-        char *raw_data;
         int rctx;
 
-        pc = preempt_count();
         __size = SIZEOF_KRETPROBE_TRACE_ENTRY(tp->nr_args);
         size = ALIGN(__size + sizeof(u32), sizeof(u64));
         size -= sizeof(u32);
         if (WARN_ONCE(size > FTRACE_MAX_PROFILE_SIZE,
                      "profile buffer not large enough"))
-                return 0;
-
-        /*
-         * Protect the non nmi buffer
-         * This also protects the rcu read side
-         */
-        local_irq_save(irq_flags);
-
-        rctx = perf_swevent_get_recursion_context();
-        if (rctx < 0)
-                goto end_recursion;
-
-        __cpu = smp_processor_id();
+                return;
 
-        if (in_nmi())
-                trace_buf = rcu_dereference(perf_trace_buf_nmi);
-        else
-                trace_buf = rcu_dereference(perf_trace_buf);
-
-        if (!trace_buf)
-                goto end;
-
-        raw_data = per_cpu_ptr(trace_buf, __cpu);
-
-        /* Zero dead bytes from alignment to avoid buffer leak to userspace */
-        *(u64 *)(&raw_data[size - sizeof(u64)]) = 0ULL;
-        entry = (struct kretprobe_trace_entry *)raw_data;
-        ent = &entry->ent;
+        entry = ftrace_perf_buf_prepare(size, call->id, &rctx, &irq_flags);
+        if (!entry)
+                return;
 
-        tracing_generic_entry_update(ent, irq_flags, pc);
-        ent->type = call->id;
         entry->nargs = tp->nr_args;
         entry->func = (unsigned long)tp->rp.kp.addr;
         entry->ret_ip = (unsigned long)ri->ret_addr;
         for (i = 0; i < tp->nr_args; i++)
                 entry->args[i] = call_fetch(&tp->args[i].fetch, regs);
-        perf_tp_event(call->id, entry->ret_ip, 1, entry, size);
-
-end:
-        perf_swevent_put_recursion_context(rctx);
-end_recursion:
-        local_irq_restore(irq_flags);
 
-        return 0;
+        ftrace_perf_buf_submit(entry, size, rctx, entry->ret_ip, 1, irq_flags);
 }
 
 static int probe_profile_enable(struct ftrace_event_call *call)
@@ -1408,7 +1299,7 @@ static void probe_profile_disable(struct ftrace_event_call *call)
                         disable_kprobe(&tp->rp.kp);
         }
 }
-#endif  /* CONFIG_EVENT_PROFILE */
+#endif  /* CONFIG_PERF_EVENTS */
 
 
 static __kprobes
@@ -1418,10 +1309,10 @@ int kprobe_dispatcher(struct kprobe *kp, struct pt_regs *regs)
 
         if (tp->flags & TP_FLAG_TRACE)
                 kprobe_trace_func(kp, regs);
-#ifdef CONFIG_EVENT_PROFILE
+#ifdef CONFIG_PERF_EVENTS
         if (tp->flags & TP_FLAG_PROFILE)
                 kprobe_profile_func(kp, regs);
-#endif  /* CONFIG_EVENT_PROFILE */
+#endif
         return 0;       /* We don't tweek kernel, so just return 0 */
 }
 
@@ -1432,10 +1323,10 @@ int kretprobe_dispatcher(struct kretprobe_instance *ri, struct pt_regs *regs)
 
         if (tp->flags & TP_FLAG_TRACE)
                 kretprobe_trace_func(ri, regs);
-#ifdef CONFIG_EVENT_PROFILE
+#ifdef CONFIG_PERF_EVENTS
         if (tp->flags & TP_FLAG_PROFILE)
                 kretprobe_profile_func(ri, regs);
-#endif  /* CONFIG_EVENT_PROFILE */
+#endif
         return 0;       /* We don't tweek kernel, so just return 0 */
 }
 
@@ -1448,23 +1339,25 @@ static int register_probe_event(struct trace_probe *tp)
         if (probe_is_return(tp)) {
                 tp->event.trace = print_kretprobe_event;
                 call->raw_init = probe_event_raw_init;
-                call->show_format = kretprobe_event_show_format;
                 call->define_fields = kretprobe_event_define_fields;
         } else {
                 tp->event.trace = print_kprobe_event;
                 call->raw_init = probe_event_raw_init;
-                call->show_format = kprobe_event_show_format;
                 call->define_fields = kprobe_event_define_fields;
         }
+        if (set_print_fmt(tp) < 0)
+                return -ENOMEM;
         call->event = &tp->event;
         call->id = register_ftrace_event(&tp->event);
-        if (!call->id)
+        if (!call->id) {
+                kfree(call->print_fmt);
                 return -ENODEV;
+        }
         call->enabled = 0;
         call->regfunc = probe_event_enable;
         call->unregfunc = probe_event_disable;
 
-#ifdef CONFIG_EVENT_PROFILE
+#ifdef CONFIG_PERF_EVENTS
         call->profile_enable = probe_profile_enable;
         call->profile_disable = probe_profile_disable;
 #endif
@@ -1472,6 +1365,7 @@ static int register_probe_event(struct trace_probe *tp)
         ret = trace_add_event_call(call);
         if (ret) {
                 pr_info("Failed to register kprobe event: %s\n", call->name);
+                kfree(call->print_fmt);
                 unregister_ftrace_event(&tp->event);
         }
         return ret;
@@ -1481,6 +1375,7 @@ static void unregister_probe_event(struct trace_probe *tp)
 {
         /* tp->event is unregistered in trace_remove_event_call() */
         trace_remove_event_call(&tp->call);
+        kfree(tp->call.print_fmt);
 }
 
 /* Make a debugfs interface for controling probe points */
@@ -1523,28 +1418,67 @@ static int kprobe_trace_selftest_target(int a1, int a2, int a3,
 
 static __init int kprobe_trace_self_tests_init(void)
 {
-        int ret;
+        int ret, warn = 0;
         int (*target)(int, int, int, int, int, int);
+        struct trace_probe *tp;
 
         target = kprobe_trace_selftest_target;
 
         pr_info("Testing kprobe tracing: ");
 
         ret = command_trace_probe("p:testprobe kprobe_trace_selftest_target "
-                                  "$arg1 $arg2 $arg3 $arg4 $stack $stack0");
-        if (WARN_ON_ONCE(ret))
-                pr_warning("error enabling function entry\n");
+                                  "$stack $stack0 +0($stack)");
+        if (WARN_ON_ONCE(ret)) {
+                pr_warning("error on probing function entry.\n");
+                warn++;
+        } else {
+                /* Enable trace point */
+                tp = find_probe_event("testprobe", KPROBE_EVENT_SYSTEM);
+                if (WARN_ON_ONCE(tp == NULL)) {
+                        pr_warning("error on getting new probe.\n");
+                        warn++;
+                } else
+                        probe_event_enable(&tp->call);
+        }
 
         ret = command_trace_probe("r:testprobe2 kprobe_trace_selftest_target "
                                   "$retval");
-        if (WARN_ON_ONCE(ret))
-                pr_warning("error enabling function return\n");
+        if (WARN_ON_ONCE(ret)) {
+                pr_warning("error on probing function return.\n");
+                warn++;
+        } else {
+                /* Enable trace point */
+                tp = find_probe_event("testprobe2", KPROBE_EVENT_SYSTEM);
+                if (WARN_ON_ONCE(tp == NULL)) {
+                        pr_warning("error on getting new probe.\n");
+                        warn++;
+                } else
+                        probe_event_enable(&tp->call);
+        }
+
+        if (warn)
+                goto end;
 
         ret = target(1, 2, 3, 4, 5, 6);
 
-        cleanup_all_probes();
+        ret = command_trace_probe("-:testprobe");
+        if (WARN_ON_ONCE(ret)) {
+                pr_warning("error on deleting a probe.\n");
+                warn++;
+        }
 
-        pr_cont("OK\n");
+        ret = command_trace_probe("-:testprobe2");
+        if (WARN_ON_ONCE(ret)) {
+                pr_warning("error on deleting a probe.\n");
+                warn++;
+        }
+
+end:
+        cleanup_all_probes();
+        if (warn)
+                pr_cont("NG: Some tests are failed. Please check them.\n");
+        else
+                pr_cont("OK\n");
         return 0;
 }