trace_syscalls: Add syscall_nr field to struct syscall_metadata

Add syscall_nr field to struct syscall_metadata,
it helps us to get syscall number easier.

Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com>
Acked-by: Jason Baron <jbaron@redhat.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <4B14D293.6090800@cn.fujitsu.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

1 files changed, 9 insertions, 13 deletions

diff --git a/kernel/trace/trace_syscalls.c b/kernel/trace/trace_syscalls.c
index 27eb18d69222..144cc14d8551 100644
--- a/kernel/trace/trace_syscalls.c
+++ b/kernel/trace/trace_syscalls.c
@@ -51,7 +51,7 @@ static struct syscall_metadata *syscall_nr_to_meta(int nr)
         return syscalls_metadata[nr];
 }
 
-int syscall_name_to_nr(const char *name)
+static int syscall_name_to_nr(const char *name)
 {
         int i;
 
@@ -342,10 +342,8 @@ int reg_event_syscall_enter(struct ftrace_event_call *call)
 {
         int ret = 0;
         int num;
-        const char *name;
 
-        name = ((struct syscall_metadata *)call->data)->name;
-        num = syscall_name_to_nr(name);
+        num = ((struct syscall_metadata *)call->data)->syscall_nr;
         if (num < 0 || num >= NR_syscalls)
                 return -ENOSYS;
         mutex_lock(&syscall_trace_lock);
@@ -365,10 +363,8 @@ int reg_event_syscall_enter(struct ftrace_event_call *call)
 void unreg_event_syscall_enter(struct ftrace_event_call *call)
 {
         int num;
-        const char *name;
 
-        name = ((struct syscall_metadata *)call->data)->name;
-        num = syscall_name_to_nr(name);
+        num = ((struct syscall_metadata *)call->data)->syscall_nr;
         if (num < 0 || num >= NR_syscalls)
                 return;
         mutex_lock(&syscall_trace_lock);
@@ -383,10 +379,8 @@ int reg_event_syscall_exit(struct ftrace_event_call *call)
 {
         int ret = 0;
         int num;
-        const char *name;
 
-        name = ((struct syscall_metadata *)call->data)->name;
-        num = syscall_name_to_nr(name);
+        num = ((struct syscall_metadata *)call->data)->syscall_nr;
         if (num < 0 || num >= NR_syscalls)
                 return -ENOSYS;
         mutex_lock(&syscall_trace_lock);
@@ -406,10 +400,8 @@ int reg_event_syscall_exit(struct ftrace_event_call *call)
 void unreg_event_syscall_exit(struct ftrace_event_call *call)
 {
         int num;
-        const char *name;
 
-        name = ((struct syscall_metadata *)call->data)->name;
-        num = syscall_name_to_nr(name);
+        num = ((struct syscall_metadata *)call->data)->syscall_nr;
         if (num < 0 || num >= NR_syscalls)
                 return;
         mutex_lock(&syscall_trace_lock);
@@ -436,6 +428,10 @@ int __init init_ftrace_syscalls(void)
         for (i = 0; i < NR_syscalls; i++) {
                 addr = arch_syscall_addr(i);
                 meta = find_syscall_meta(addr);
+                if (!meta)
+                        continue;
+
+                meta->syscall_nr = i;
                 syscalls_metadata[i] = meta;
         }