trace_syscalls: Remove enter_id exit_id
[firefly-linux-kernel-4.4.55.git] / kernel / trace / trace_syscalls.c
index 527e17eae57516a1f36932d13e1799d1244ef03f..27eb18d69222a7d3dafbb25f8bfef07145c3a0f7 100644 (file)
@@ -14,6 +14,59 @@ static int sys_refcount_exit;
 static DECLARE_BITMAP(enabled_enter_syscalls, NR_syscalls);
 static DECLARE_BITMAP(enabled_exit_syscalls, NR_syscalls);
 
+extern unsigned long __start_syscalls_metadata[];
+extern unsigned long __stop_syscalls_metadata[];
+
+static struct syscall_metadata **syscalls_metadata;
+
+static struct syscall_metadata *find_syscall_meta(unsigned long syscall)
+{
+       struct syscall_metadata *start;
+       struct syscall_metadata *stop;
+       char str[KSYM_SYMBOL_LEN];
+
+
+       start = (struct syscall_metadata *)__start_syscalls_metadata;
+       stop = (struct syscall_metadata *)__stop_syscalls_metadata;
+       kallsyms_lookup(syscall, NULL, NULL, NULL, str);
+
+       for ( ; start < stop; start++) {
+               /*
+                * Only compare after the "sys" prefix. Archs that use
+                * syscall wrappers may have syscalls symbols aliases prefixed
+                * with "SyS" instead of "sys", leading to an unwanted
+                * mismatch.
+                */
+               if (start->name && !strcmp(start->name + 3, str + 3))
+                       return start;
+       }
+       return NULL;
+}
+
+static struct syscall_metadata *syscall_nr_to_meta(int nr)
+{
+       if (!syscalls_metadata || nr >= NR_syscalls || nr < 0)
+               return NULL;
+
+       return syscalls_metadata[nr];
+}
+
+int syscall_name_to_nr(const char *name)
+{
+       int i;
+
+       if (!syscalls_metadata)
+               return -1;
+
+       for (i = 0; i < NR_syscalls; i++) {
+               if (syscalls_metadata[i]) {
+                       if (!strcmp(syscalls_metadata[i]->name, name))
+                               return i;
+               }
+       }
+       return -1;
+}
+
 enum print_line_t
 print_syscall_enter(struct trace_iterator *iter, int flags)
 {
@@ -30,7 +83,7 @@ print_syscall_enter(struct trace_iterator *iter, int flags)
        if (!entry)
                goto end;
 
-       if (entry->enter_id != ent->type) {
+       if (entry->enter_event->id != ent->type) {
                WARN_ON_ONCE(1);
                goto end;
        }
@@ -85,7 +138,7 @@ print_syscall_exit(struct trace_iterator *iter, int flags)
                return TRACE_TYPE_HANDLED;
        }
 
-       if (entry->exit_id != ent->type) {
+       if (entry->exit_event->id != ent->type) {
                WARN_ON_ONCE(1);
                return TRACE_TYPE_UNHANDLED;
        }
@@ -103,24 +156,19 @@ extern char *__bad_type_size(void);
 #define SYSCALL_FIELD(type, name)                                      \
        sizeof(type) != sizeof(trace.name) ?                            \
                __bad_type_size() :                                     \
-               #type, #name, offsetof(typeof(trace), name), sizeof(trace.name)
+               #type, #name, offsetof(typeof(trace), name),            \
+               sizeof(trace.name), is_signed_type(type)
 
 int syscall_enter_format(struct ftrace_event_call *call, struct trace_seq *s)
 {
        int i;
-       int nr;
        int ret;
-       struct syscall_metadata *entry;
+       struct syscall_metadata *entry = call->data;
        struct syscall_trace_enter trace;
        int offset = offsetof(struct syscall_trace_enter, args);
 
-       nr = syscall_name_to_nr(call->data);
-       entry = syscall_nr_to_meta(nr);
-
-       if (!entry)
-               return 0;
-
-       ret = trace_seq_printf(s, "\tfield:%s %s;\toffset:%zu;\tsize:%zu;\n",
+       ret = trace_seq_printf(s, "\tfield:%s %s;\toffset:%zu;\tsize:%zu;"
+                              "\tsigned:%u;\n",
                               SYSCALL_FIELD(int, nr));
        if (!ret)
                return 0;
@@ -130,8 +178,10 @@ int syscall_enter_format(struct ftrace_event_call *call, struct trace_seq *s)
                                        entry->args[i]);
                if (!ret)
                        return 0;
-               ret = trace_seq_printf(s, "\toffset:%d;\tsize:%zu;\n", offset,
-                                      sizeof(unsigned long));
+               ret = trace_seq_printf(s, "\toffset:%d;\tsize:%zu;"
+                                      "\tsigned:%u;\n", offset,
+                                      sizeof(unsigned long),
+                                      is_signed_type(unsigned long));
                if (!ret)
                        return 0;
                offset += sizeof(unsigned long);
@@ -163,8 +213,10 @@ int syscall_exit_format(struct ftrace_event_call *call, struct trace_seq *s)
        struct syscall_trace_exit trace;
 
        ret = trace_seq_printf(s,
-                              "\tfield:%s %s;\toffset:%zu;\tsize:%zu;\n"
-                              "\tfield:%s %s;\toffset:%zu;\tsize:%zu;\n",
+                              "\tfield:%s %s;\toffset:%zu;\tsize:%zu;"
+                              "\tsigned:%u;\n"
+                              "\tfield:%s %s;\toffset:%zu;\tsize:%zu;"
+                              "\tsigned:%u;\n",
                               SYSCALL_FIELD(int, nr),
                               SYSCALL_FIELD(long, ret));
        if (!ret)
@@ -176,22 +228,19 @@ int syscall_exit_format(struct ftrace_event_call *call, struct trace_seq *s)
 int syscall_enter_define_fields(struct ftrace_event_call *call)
 {
        struct syscall_trace_enter trace;
-       struct syscall_metadata *meta;
+       struct syscall_metadata *meta = call->data;
        int ret;
-       int nr;
        int i;
        int offset = offsetof(typeof(trace), args);
 
-       nr = syscall_name_to_nr(call->data);
-       meta = syscall_nr_to_meta(nr);
-
-       if (!meta)
-               return 0;
-
        ret = trace_define_common_fields(call);
        if (ret)
                return ret;
 
+       ret = trace_define_field(call, SYSCALL_FIELD(int, nr), FILTER_OTHER);
+       if (ret)
+               return ret;
+
        for (i = 0; i < meta->nb_args; i++) {
                ret = trace_define_field(call, meta->types[i],
                                         meta->args[i], offset,
@@ -212,7 +261,11 @@ int syscall_exit_define_fields(struct ftrace_event_call *call)
        if (ret)
                return ret;
 
-       ret = trace_define_field(call, SYSCALL_FIELD(long, ret), 0,
+       ret = trace_define_field(call, SYSCALL_FIELD(int, nr), FILTER_OTHER);
+       if (ret)
+               return ret;
+
+       ret = trace_define_field(call, SYSCALL_FIELD(long, ret),
                                 FILTER_OTHER);
 
        return ret;
@@ -239,8 +292,8 @@ void ftrace_syscall_enter(struct pt_regs *regs, long id)
 
        size = sizeof(*entry) + sizeof(unsigned long) * sys_data->nb_args;
 
-       event = trace_current_buffer_lock_reserve(&buffer, sys_data->enter_id,
-                                                 size, 0, 0);
+       event = trace_current_buffer_lock_reserve(&buffer,
+                       sys_data->enter_event->id, size, 0, 0);
        if (!event)
                return;
 
@@ -271,8 +324,8 @@ void ftrace_syscall_exit(struct pt_regs *regs, long ret)
        if (!sys_data)
                return;
 
-       event = trace_current_buffer_lock_reserve(&buffer, sys_data->exit_id,
-                               sizeof(*entry), 0, 0);
+       event = trace_current_buffer_lock_reserve(&buffer,
+                       sys_data->exit_event->id, sizeof(*entry), 0, 0);
        if (!event)
                return;
 
@@ -285,13 +338,13 @@ void ftrace_syscall_exit(struct pt_regs *regs, long ret)
                trace_current_buffer_unlock_commit(buffer, event, 0, 0);
 }
 
-int reg_event_syscall_enter(void *ptr)
+int reg_event_syscall_enter(struct ftrace_event_call *call)
 {
        int ret = 0;
        int num;
-       char *name;
+       const char *name;
 
-       name = (char *)ptr;
+       name = ((struct syscall_metadata *)call->data)->name;
        num = syscall_name_to_nr(name);
        if (num < 0 || num >= NR_syscalls)
                return -ENOSYS;
@@ -309,12 +362,12 @@ int reg_event_syscall_enter(void *ptr)
        return ret;
 }
 
-void unreg_event_syscall_enter(void *ptr)
+void unreg_event_syscall_enter(struct ftrace_event_call *call)
 {
        int num;
-       char *name;
+       const char *name;
 
-       name = (char *)ptr;
+       name = ((struct syscall_metadata *)call->data)->name;
        num = syscall_name_to_nr(name);
        if (num < 0 || num >= NR_syscalls)
                return;
@@ -326,13 +379,13 @@ void unreg_event_syscall_enter(void *ptr)
        mutex_unlock(&syscall_trace_lock);
 }
 
-int reg_event_syscall_exit(void *ptr)
+int reg_event_syscall_exit(struct ftrace_event_call *call)
 {
        int ret = 0;
        int num;
-       char *name;
+       const char *name;
 
-       name = (char *)ptr;
+       name = ((struct syscall_metadata *)call->data)->name;
        num = syscall_name_to_nr(name);
        if (num < 0 || num >= NR_syscalls)
                return -ENOSYS;
@@ -350,12 +403,12 @@ int reg_event_syscall_exit(void *ptr)
        return ret;
 }
 
-void unreg_event_syscall_exit(void *ptr)
+void unreg_event_syscall_exit(struct ftrace_event_call *call)
 {
        int num;
-       char *name;
+       const char *name;
 
-       name = (char *)ptr;
+       name = ((struct syscall_metadata *)call->data)->name;
        num = syscall_name_to_nr(name);
        if (num < 0 || num >= NR_syscalls)
                return;
@@ -367,13 +420,28 @@ void unreg_event_syscall_exit(void *ptr)
        mutex_unlock(&syscall_trace_lock);
 }
 
-struct trace_event event_syscall_enter = {
-       .trace                  = print_syscall_enter,
-};
+int __init init_ftrace_syscalls(void)
+{
+       struct syscall_metadata *meta;
+       unsigned long addr;
+       int i;
 
-struct trace_event event_syscall_exit = {
-       .trace                  = print_syscall_exit,
-};
+       syscalls_metadata = kzalloc(sizeof(*syscalls_metadata) *
+                                       NR_syscalls, GFP_KERNEL);
+       if (!syscalls_metadata) {
+               WARN_ON(1);
+               return -ENOMEM;
+       }
+
+       for (i = 0; i < NR_syscalls; i++) {
+               addr = arch_syscall_addr(i);
+               meta = find_syscall_meta(addr);
+               syscalls_metadata[i] = meta;
+       }
+
+       return 0;
+}
+core_initcall(init_ftrace_syscalls);
 
 #ifdef CONFIG_EVENT_PROFILE
 
@@ -387,8 +455,10 @@ static void prof_syscall_enter(struct pt_regs *regs, long id)
        struct syscall_metadata *sys_data;
        struct syscall_trace_enter *rec;
        unsigned long flags;
+       char *trace_buf;
        char *raw_data;
        int syscall_nr;
+       int rctx;
        int size;
        int cpu;
 
@@ -412,30 +482,33 @@ static void prof_syscall_enter(struct pt_regs *regs, long id)
        /* Protect the per cpu buffer, begin the rcu read side */
        local_irq_save(flags);
 
+       rctx = perf_swevent_get_recursion_context();
+       if (rctx < 0)
+               goto end_recursion;
+
        cpu = smp_processor_id();
 
-       if (in_nmi())
-               raw_data = rcu_dereference(trace_profile_buf_nmi);
-       else
-               raw_data = rcu_dereference(trace_profile_buf);
+       trace_buf = rcu_dereference(perf_trace_buf);
 
-       if (!raw_data)
+       if (!trace_buf)
                goto end;
 
-       raw_data = per_cpu_ptr(raw_data, cpu);
+       raw_data = per_cpu_ptr(trace_buf, cpu);
 
        /* zero the dead bytes from align to not leak stack to user */
        *(u64 *)(&raw_data[size - sizeof(u64)]) = 0ULL;
 
        rec = (struct syscall_trace_enter *) raw_data;
        tracing_generic_entry_update(&rec->ent, 0, 0);
-       rec->ent.type = sys_data->enter_id;
+       rec->ent.type = sys_data->enter_event->id;
        rec->nr = syscall_nr;
        syscall_get_arguments(current, regs, 0, sys_data->nb_args,
                               (unsigned long *)&rec->args);
-       perf_tp_event(sys_data->enter_id, 0, 1, rec, size);
+       perf_tp_event(sys_data->enter_event->id, 0, 1, rec, size);
 
 end:
+       perf_swevent_put_recursion_context(rctx);
+end_recursion:
        local_irq_restore(flags);
 }
 
@@ -484,7 +557,9 @@ static void prof_syscall_exit(struct pt_regs *regs, long ret)
        struct syscall_trace_exit *rec;
        unsigned long flags;
        int syscall_nr;
+       char *trace_buf;
        char *raw_data;
+       int rctx;
        int size;
        int cpu;
 
@@ -510,17 +585,19 @@ static void prof_syscall_exit(struct pt_regs *regs, long ret)
 
        /* Protect the per cpu buffer, begin the rcu read side */
        local_irq_save(flags);
+
+       rctx = perf_swevent_get_recursion_context();
+       if (rctx < 0)
+               goto end_recursion;
+
        cpu = smp_processor_id();
 
-       if (in_nmi())
-               raw_data = rcu_dereference(trace_profile_buf_nmi);
-       else
-               raw_data = rcu_dereference(trace_profile_buf);
+       trace_buf = rcu_dereference(perf_trace_buf);
 
-       if (!raw_data)
+       if (!trace_buf)
                goto end;
 
-       raw_data = per_cpu_ptr(raw_data, cpu);
+       raw_data = per_cpu_ptr(trace_buf, cpu);
 
        /* zero the dead bytes from align to not leak stack to user */
        *(u64 *)(&raw_data[size - sizeof(u64)]) = 0ULL;
@@ -528,13 +605,15 @@ static void prof_syscall_exit(struct pt_regs *regs, long ret)
        rec = (struct syscall_trace_exit *)raw_data;
 
        tracing_generic_entry_update(&rec->ent, 0, 0);
-       rec->ent.type = sys_data->exit_id;
+       rec->ent.type = sys_data->exit_event->id;
        rec->nr = syscall_nr;
        rec->ret = syscall_get_return_value(current, regs);
 
-       perf_tp_event(sys_data->exit_id, 0, 1, rec, size);
+       perf_tp_event(sys_data->exit_event->id, 0, 1, rec, size);
 
 end:
+       perf_swevent_put_recursion_context(rctx);
+end_recursion:
        local_irq_restore(flags);
 }