[tip:tracing/core] tracing/syscalls: Fix fields format for enter events

From: tip-bot for Li Zefan
Date: Wed Aug 19 2009 - 09:31:52 EST


Commit-ID: e6971969c331caa5c3c88cbd1be4f465b3355452
Gitweb: http://git.kernel.org/tip/e6971969c331caa5c3c88cbd1be4f465b3355452
Author: Li Zefan <lizf@xxxxxxxxxxxxxx>
AuthorDate: Wed, 19 Aug 2009 15:52:25 +0800
Committer: Ingo Molnar <mingo@xxxxxxx>
CommitDate: Wed, 19 Aug 2009 15:02:22 +0200

tracing/syscalls: Fix fields format for enter events

The "format" file of a trace event is originally for parsers to
parse ftrace binary output.

But the "format" file of a syscall event can only be used by
perfcounter, because it describes the format of struct
syscall_enter_record not struct syscall_trace_enter.

To fix this, we remove struct syscall_enter_record, and then
struct syscall_trace_enter will be used by both perf profile
and ftrace.

Signed-off-by: Li Zefan <lizf@xxxxxxxxxxxxxx>
Cc: Jason Baron <jbaron@xxxxxxxxxx>
Cc: Steven Rostedt <rostedt@xxxxxxxxxxx>
Cc: Frederic Weisbecker <fweisbec@xxxxxxxxx>
LKML-Reference: <4A8BAF39.1030404@xxxxxxxxxxxxxx>
Signed-off-by: Ingo Molnar <mingo@xxxxxxx>


---
kernel/trace/trace_syscalls.c | 51 ++++++++++++++++++++++------------------
1 files changed, 28 insertions(+), 23 deletions(-)

diff --git a/kernel/trace/trace_syscalls.c b/kernel/trace/trace_syscalls.c
index f130dac..d10daf0 100644
--- a/kernel/trace/trace_syscalls.c
+++ b/kernel/trace/trace_syscalls.c
@@ -90,26 +90,39 @@ print_syscall_exit(struct trace_iterator *iter, int flags)
return TRACE_TYPE_HANDLED;
}

+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)
+
int ftrace_format_syscall(struct ftrace_event_call *call, struct trace_seq *s)
{
int i;
int nr;
- int ret = 0;
+ int ret;
struct syscall_metadata *entry;
- int offset = sizeof(struct trace_entry);
+ struct syscall_trace_enter trace;
+ int offset = offsetof(struct syscall_trace_enter, args);

- nr = syscall_name_to_nr((char *)call->data);
+ nr = syscall_name_to_nr(call->data);
entry = syscall_nr_to_meta(nr);

if (!entry)
- return ret;
+ return 0;
+
+ ret = trace_seq_printf(s, "\tfield:%s %s;\toffset:%zu;\tsize:%zu;\n",
+ SYSCALL_FIELD(int, nr));
+ if (!ret)
+ return 0;

for (i = 0; i < entry->nb_args; i++) {
ret = trace_seq_printf(s, "\tfield:%s %s;", entry->types[i],
entry->args[i]);
if (!ret)
return 0;
- ret = trace_seq_printf(s, "\toffset:%d;\tsize:%lu;\n", offset,
+ ret = trace_seq_printf(s, "\toffset:%d;\tsize:%zu;\n", offset,
sizeof(unsigned long));
if (!ret)
return 0;
@@ -118,7 +131,7 @@ int ftrace_format_syscall(struct ftrace_event_call *call, struct trace_seq *s)

trace_seq_printf(s, "\nprint fmt: \"");
for (i = 0; i < entry->nb_args; i++) {
- ret = trace_seq_printf(s, "%s: 0x%%0%lulx%s", entry->args[i],
+ ret = trace_seq_printf(s, "%s: 0x%%0%zulx%s", entry->args[i],
sizeof(unsigned long),
i == entry->nb_args - 1 ? "\", " : ", ");
if (!ret)
@@ -287,16 +300,6 @@ struct trace_event event_syscall_exit = {

#ifdef CONFIG_EVENT_PROFILE

-struct syscall_enter_record {
- struct trace_entry entry;
- unsigned long args[0];
-};
-
-struct syscall_exit_record {
- struct trace_entry entry;
- unsigned long ret;
-};
-
static DECLARE_BITMAP(enabled_prof_enter_syscalls, FTRACE_SYSCALL_MAX);
static DECLARE_BITMAP(enabled_prof_exit_syscalls, FTRACE_SYSCALL_MAX);
static int sys_prof_refcount_enter;
@@ -304,7 +307,7 @@ static int sys_prof_refcount_exit;

static void prof_syscall_enter(struct pt_regs *regs, long id)
{
- struct syscall_enter_record *rec;
+ struct syscall_trace_enter *rec;
struct syscall_metadata *sys_data;
int syscall_nr;
int size;
@@ -328,9 +331,10 @@ static void prof_syscall_enter(struct pt_regs *regs, long id)
/* zero the dead bytes from align to not leak stack to user */
*(u64 *)(&raw_data[size - sizeof(u64)]) = 0ULL;

- rec = (struct syscall_enter_record *) raw_data;
- tracing_generic_entry_update(&rec->entry, 0, 0);
- rec->entry.type = sys_data->enter_id;
+ rec = (struct syscall_trace_enter *) raw_data;
+ tracing_generic_entry_update(&rec->ent, 0, 0);
+ rec->ent.type = sys_data->enter_id;
+ rec->nr = syscall_nr;
syscall_get_arguments(current, regs, 0, sys_data->nb_args,
(unsigned long *)&rec->args);
perf_tpcounter_event(sys_data->enter_id, 0, 1, rec, size);
@@ -379,7 +383,7 @@ void unreg_prof_syscall_enter(char *name)
static void prof_syscall_exit(struct pt_regs *regs, long ret)
{
struct syscall_metadata *sys_data;
- struct syscall_exit_record rec;
+ struct syscall_trace_exit rec;
int syscall_nr;

syscall_nr = syscall_get_nr(current, regs);
@@ -390,8 +394,9 @@ static void prof_syscall_exit(struct pt_regs *regs, long ret)
if (!sys_data)
return;

- tracing_generic_entry_update(&rec.entry, 0, 0);
- rec.entry.type = sys_data->exit_id;
+ tracing_generic_entry_update(&rec.ent, 0, 0);
+ rec.ent.type = sys_data->exit_id;
+ rec.nr = syscall_nr;
rec.ret = syscall_get_return_value(current, regs);

perf_tpcounter_event(sys_data->exit_id, 0, 1, &rec, sizeof(rec));
--
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