tracing/kprobe: Drop function argument access syntax

Drop function argument access syntax, because the function
arguments depend on not only architecture but also
compile-options and function API. And now, we have perf-probe
for finding register/memory assigned to each argument.

Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: systemtap <systemtap@sources.redhat.com>
Cc: DLE <dle-develop@lists.sourceforge.net>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Roland McGrath <roland@redhat.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Michael Neuling <mikey@neuling.org>
Cc: linuxppc-dev@ozlabs.org
LKML-Reference: <20100105224648.19431.52309.stgit@dhcp-100-2-132.bos.redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

1 files changed, 1 insertions, 17 deletions

diff --git a/kernel/trace/trace_kprobe.c b/kernel/trace/trace_kprobe.c
index 47f54ab57b68..7ac728ded964 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-)