2 files changed, 155 insertions, 8 deletions

diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h
index 56ce34d90b03..f56162806f50 100644
--- a/kernel/trace/trace.h
+++ b/kernel/trace/trace.h
@@ -202,6 +202,19 @@ struct kmemtrace_free_entry {
         const void *ptr;
 };
 
+struct syscall_trace_enter {
+        struct trace_entry      ent;
+        int                     nr;
+        unsigned long           args[];
+};
+
+struct syscall_trace_exit {
+        struct trace_entry      ent;
+        int                     nr;
+        unsigned long           ret;
+};
+
+
 /*
  * trace_flag_type is an enumeration that holds different
  * states when a trace occurs. These are:
@@ -315,6 +328,10 @@ extern void __ftrace_bad_type(void);
                           TRACE_KMEM_ALLOC);    \
                 IF_ASSIGN(var, ent, struct kmemtrace_free_entry,        \
                           TRACE_KMEM_FREE);     \
+                IF_ASSIGN(var, ent, struct syscall_trace_enter,         \
+                          TRACE_SYSCALL_ENTER);                         \
+                IF_ASSIGN(var, ent, struct syscall_trace_exit,          \
+                          TRACE_SYSCALL_EXIT);                          \
                 __ftrace_bad_type();                                    \
         } while (0)
 
diff --git a/kernel/trace/trace_syscalls.c b/kernel/trace/trace_syscalls.c
index 66cf97449af3..c72e599230ff 100644
--- a/kernel/trace/trace_syscalls.c
+++ b/kernel/trace/trace_syscalls.c
@@ -1,6 +1,5 @@
-#include <linux/ftrace.h>
 #include <linux/kernel.h>
-
+#include <linux/ftrace.h>
 #include <asm/syscall.h>
 
 #include "trace_output.h"
@@ -8,6 +7,90 @@
 
 static atomic_t refcount;
 
+/* Our two options */
+enum {
+        TRACE_SYSCALLS_OPT_TYPES = 0x1,
+};
+
+static struct tracer_opt syscalls_opts[] = {
+        { TRACER_OPT(syscall_arg_type, TRACE_SYSCALLS_OPT_TYPES) },
+        { }
+};
+
+static struct tracer_flags syscalls_flags = {
+        .val = 0, /* By default: no args types */
+        .opts = syscalls_opts
+};
+
+enum print_line_t
+print_syscall_enter(struct trace_iterator *iter, int flags)
+{
+        struct trace_seq *s = &iter->seq;
+        struct trace_entry *ent = iter->ent;
+        struct syscall_trace_enter *trace;
+        struct syscall_metadata *entry;
+        int i, ret, syscall;
+
+        trace_assign_type(trace, ent);
+
+        syscall = trace->nr;
+
+        entry = syscall_nr_to_meta(syscall);
+        if (!entry)
+                goto end;
+
+        ret = trace_seq_printf(s, "%s(", entry->name);
+        if (!ret)
+                return TRACE_TYPE_PARTIAL_LINE;
+
+        for (i = 0; i < entry->nb_args; i++) {
+                /* parameter types */
+                if (syscalls_flags.val & TRACE_SYSCALLS_OPT_TYPES) {
+                        ret = trace_seq_printf(s, "%s ", entry->types[i]);
+                        if (!ret)
+                                return TRACE_TYPE_PARTIAL_LINE;
+                }
+                /* parameter values */
+                ret = trace_seq_printf(s, "%s: %lx%s ", entry->args[i],
+                                       trace->args[i],
+                                       i == entry->nb_args - 1 ? ")" : ",");
+                if (!ret)
+                        return TRACE_TYPE_PARTIAL_LINE;
+        }
+
+end:
+        trace_seq_printf(s, "\n");
+        return TRACE_TYPE_HANDLED;
+}
+
+enum print_line_t
+print_syscall_exit(struct trace_iterator *iter, int flags)
+{
+        struct trace_seq *s = &iter->seq;
+        struct trace_entry *ent = iter->ent;
+        struct syscall_trace_exit *trace;
+        int syscall;
+        struct syscall_metadata *entry;
+        int ret;
+
+        trace_assign_type(trace, ent);
+
+        syscall = trace->nr;
+
+        entry = syscall_nr_to_meta(syscall);
+        if (!entry) {
+                trace_seq_printf(s, "\n");
+                return TRACE_TYPE_HANDLED;
+        }
+
+        ret = trace_seq_printf(s, "%s -> 0x%lx\n", entry->name,
+                                trace->ret);
+        if (!ret)
+                return TRACE_TYPE_PARTIAL_LINE;
+
+        return TRACE_TYPE_HANDLED;
+}
+
 void start_ftrace_syscalls(void)
 {
         unsigned long flags;
@@ -16,6 +99,7 @@ void start_ftrace_syscalls(void)
         if (atomic_inc_return(&refcount) != 1)
                 goto out;
 
+        arch_init_ftrace_syscalls();
         read_lock_irqsave(&tasklist_lock, flags);
 
         do_each_thread(g, t) {
@@ -48,20 +132,63 @@ out:
 
 void ftrace_syscall_enter(struct pt_regs *regs)
 {
+        struct syscall_trace_enter *entry;
+        struct syscall_metadata *sys_data;
+        struct ring_buffer_event *event;
+        int size;
         int syscall_nr;
+        int cpu;
 
         syscall_nr = syscall_get_nr(current, regs);
 
-        trace_printk("syscall %d enter\n", syscall_nr);
+        cpu = raw_smp_processor_id();
+
+        sys_data = syscall_nr_to_meta(syscall_nr);
+        if (!sys_data)
+                return;
+
+        size = sizeof(*entry) + sizeof(unsigned long) * sys_data->nb_args;
+
+        event = trace_current_buffer_lock_reserve(TRACE_SYSCALL_ENTER, size,
+                                                        0, 0);
+        if (!event)
+                return;
+
+        entry = ring_buffer_event_data(event);
+        entry->nr = syscall_nr;
+        syscall_get_arguments(current, regs, 0, sys_data->nb_args, entry->args);
+
+        trace_current_buffer_unlock_commit(event, 0, 0);
+        trace_wake_up();
 }
 
 void ftrace_syscall_exit(struct pt_regs *regs)
 {
+        struct syscall_trace_exit *entry;
+        struct syscall_metadata *sys_data;
+        struct ring_buffer_event *event;
         int syscall_nr;
+        int cpu;
 
         syscall_nr = syscall_get_nr(current, regs);
 
-        trace_printk("syscall %d exit\n", syscall_nr);
+        cpu = raw_smp_processor_id();
+
+        sys_data = syscall_nr_to_meta(syscall_nr);
+        if (!sys_data)
+                return;
+
+        event = trace_current_buffer_lock_reserve(TRACE_SYSCALL_EXIT,
+                                sizeof(*entry), 0, 0);
+        if (!event)
+                return;
+
+        entry = ring_buffer_event_data(event);
+        entry->nr = syscall_nr;
+        entry->ret = syscall_get_return_value(current, regs);
+
+        trace_current_buffer_unlock_commit(event, 0, 0);
+        trace_wake_up();
 }
 
 static int init_syscall_tracer(struct trace_array *tr)
@@ -77,17 +204,20 @@ static void reset_syscall_tracer(struct trace_array *tr)
 }
 
 static struct trace_event syscall_enter_event = {
-        .type           = TRACE_SYSCALL_ENTER,
+        .type           = TRACE_SYSCALL_ENTER,
+        .trace          = print_syscall_enter,
 };
 
 static struct trace_event syscall_exit_event = {
-        .type           = TRACE_SYSCALL_EXIT,
+        .type           = TRACE_SYSCALL_EXIT,
+        .trace          = print_syscall_exit,
 };
 
 static struct tracer syscall_tracer __read_mostly = {
-        .name           = "syscall",
+        .name           = "syscall",
         .init           = init_syscall_tracer,
-        .reset          = reset_syscall_tracer
+        .reset          = reset_syscall_tracer,
+        .flags          = &syscalls_flags,
 };
 
 __init int register_ftrace_syscalls(void)