[PATCH v6 05/21] tracing: probeevent: Cleanup print argument functions

Masami Hiramatsu
2018-03-17T12:41:53Z

Current print argument functions prints the argument
name too. It is not good for printing out multiple
values for one argument. This change it to just print
out the value.

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
---
kernel/trace/trace_kprobe.c | 20 ++++++--------------
kernel/trace/trace_probe.c | 12 +++++-------
kernel/trace/trace_probe.h | 19 ++++++++++++++++---
kernel/trace/trace_uprobe.c | 9 ++-------
4 files changed, 29 insertions(+), 31 deletions(-)

diff --git a/kernel/trace/trace_kprobe.c b/kernel/trace/trace_kprobe.c
index 1cd3fb4d70f8..81e2eb5a1566 100644
--- a/kernel/trace/trace_kprobe.c
+++ b/kernel/trace/trace_kprobe.c
@@ -1090,8 +1090,6 @@ print_kprobe_event(struct trace_iterator *iter, int flags,
struct kprobe_trace_entry_head *field;
struct trace_seq *s = &iter->seq;
struct trace_probe *tp;
- u8 *data;
- int i;

field = (struct kprobe_trace_entry_head *)iter->ent;
tp = container_of(event, struct trace_probe, call.event);
@@ -1103,11 +1101,9 @@ print_kprobe_event(struct trace_iterator *iter, int flags,

trace_seq_putc(s, ')');

- data = (u8 *)&field[1];
- for (i = 0; i < tp->nr_args; i++)
- if (!tp->args[i].type->print(s, tp->args[i].name,
- data + tp->args[i].offset, field))
- goto out;
+ if (print_probe_args(s, tp->args, tp->nr_args,
+ (u8 *)&field[1], field) < 0)
+ goto out;

trace_seq_putc(s, '\n');
out:
@@ -1121,8 +1117,6 @@ print_kretprobe_event(struct trace_iterator *iter, int flags,
struct kretprobe_trace_entry_head *field;
struct trace_seq *s = &iter->seq;
struct trace_probe *tp;
- u8 *data;
- int i;

field = (struct kretprobe_trace_entry_head *)iter->ent;
tp = container_of(event, struct trace_probe, call.event);
@@ -1139,11 +1133,9 @@ print_kretprobe_event(struct trace_iterator *iter, int flags,

trace_seq_putc(s, ')');

- data = (u8 *)&field[1];
- for (i = 0; i < tp->nr_args; i++)
- if (!tp->args[i].type->print(s, tp->args[i].name,
- data + tp->args[i].offset, field))
- goto out;
+ if (print_probe_args(s, tp->args, tp->nr_args,
+ (u8 *)&field[1], field) < 0)
+ goto out;

trace_seq_putc(s, '\n');

diff --git a/kernel/trace/trace_probe.c b/kernel/trace/trace_probe.c
index daf54bda4dc8..8894b81e29b0 100644
--- a/kernel/trace/trace_probe.c
+++ b/kernel/trace/trace_probe.c
@@ -38,10 +38,9 @@ const char *reserved_field_names[] = {

/* Printing in basic type function template */
#define DEFINE_BASIC_PRINT_TYPE_FUNC(tname, type, fmt) \
-int PRINT_TYPE_FUNC_NAME(tname)(struct trace_seq *s, const char *name, \
- void *data, void *ent) \
+int PRINT_TYPE_FUNC_NAME(tname)(struct trace_seq *s, void *data, void *ent)\
{ \
- trace_seq_printf(s, " %s=" fmt, name, *(type *)data); \
+ trace_seq_printf(s, fmt, *(type *)data); \
return !trace_seq_has_overflowed(s); \
} \
const char PRINT_TYPE_FMT_NAME(tname)[] = fmt; \
@@ -61,15 +60,14 @@ DEFINE_BASIC_PRINT_TYPE_FUNC(x32, u32, "0x%x")
DEFINE_BASIC_PRINT_TYPE_FUNC(x64, u64, "0x%Lx")

/* Print type function for string type */
-int PRINT_TYPE_FUNC_NAME(string)(struct trace_seq *s, const char *name,
- void *data, void *ent)
+int PRINT_TYPE_FUNC_NAME(string)(struct trace_seq *s, void *data, void *ent)
{
int len = *(u32 *)data >> 16;

if (!len)
- trace_seq_printf(s, " %s=(fault)", name);
+ trace_seq_puts(s, "(fault)");
else
- trace_seq_printf(s, " %s=\"%s\"", name,
+ trace_seq_printf(s, "\"%s\"",
(const char *)get_loc_data(data, ent));
return !trace_seq_has_overflowed(s);
}
diff --git a/kernel/trace/trace_probe.h b/kernel/trace/trace_probe.h
index 75daff22ccea..0c8e66f9c855 100644
--- a/kernel/trace/trace_probe.h
+++ b/kernel/trace/trace_probe.h
@@ -94,7 +94,7 @@ static nokprobe_inline void *get_loc_data(u32 *dl, void *ent)
/* Data fetch function type */
typedef void (*fetch_func_t)(struct pt_regs *, void *, void *);
/* Printing function type */
-typedef int (*print_type_func_t)(struct trace_seq *, const char *, void *, void *);
+typedef int (*print_type_func_t)(struct trace_seq *, void *, void *);

/* Fetch types */
enum {
@@ -136,8 +136,7 @@ typedef u32 string_size;

/* Printing in basic type function template */
#define DECLARE_BASIC_PRINT_TYPE_FUNC(type) \
-int PRINT_TYPE_FUNC_NAME(type)(struct trace_seq *s, const char *name, \
- void *data, void *ent); \
+int PRINT_TYPE_FUNC_NAME(type)(struct trace_seq *s, void *data, void *ent);\
extern const char PRINT_TYPE_FMT_NAME(type)[]

DECLARE_BASIC_PRINT_TYPE_FUNC(u8);
@@ -415,6 +414,20 @@ store_trace_args(int ent_size, struct trace_probe *tp, struct pt_regs *regs,
}
}

+static inline int
+print_probe_args(struct trace_seq *s, struct probe_arg *args, int nr_args,
+ u8 *data, void *field)
+{
+ int i;
+
+ for (i = 0; i < nr_args; i++) {
+ trace_seq_printf(s, " %s=", args[i].name);
+ if (!args[i].type->print(s, data + args[i].offset, field))
+ return -ENOMEM;
+ }
+ return 0;
+}
+
extern int set_print_fmt(struct trace_probe *tp, bool is_return);

#ifdef CONFIG_PERF_EVENTS
diff --git a/kernel/trace/trace_uprobe.c b/kernel/trace/trace_uprobe.c
index 2014f4351ae0..4c006a693663 100644
--- a/kernel/trace/trace_uprobe.c
+++ b/kernel/trace/trace_uprobe.c
@@ -864,7 +864,6 @@ print_uprobe_event(struct trace_iterator *iter, int flags, struct trace_event *e
struct trace_seq *s = &iter->seq;
struct trace_uprobe *tu;
u8 *data;
- int i;

entry = (struct uprobe_trace_entry_head *)iter->ent;
tu = container_of(event, struct trace_uprobe, tp.call.event);
@@ -881,12 +880,8 @@ print_uprobe_event(struct trace_iterator *iter, int flags, struct trace_event *e
data = DATAOF_TRACE_ENTRY(entry, false);
}

- for (i = 0; i < tu->tp.nr_args; i++) {
- struct probe_arg *parg = &tu->tp.args[i];
-
- if (!parg->type->print(s, parg->name, data + parg->offset, entry))
- goto out;
- }
+ if (print_probe_args(s, tu->tp.args, tu->tp.nr_args, data, entry) < 0)
+ goto out;

trace_seq_putc(s, '\n');