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uprobes/tracing: Generalize struct uprobe_trace_entry_head

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struct uprobe_trace_entry_head has a single member for reporting,
"unsigned long ip". If we want to support uretprobes we need to
create another struct which has "func" and "ret_ip" and duplicate
a lot of functions, like trace_kprobe.c does.

To avoid this copy-and-paste horror we turn ->ip into ->vaddr[]
and add couple of trivial helpers to calculate sizeof/data. This
uglifies the code a bit, but this allows us to avoid a lot more
complications later, when we add the support for ret-probes.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Tested-by: Anton Arapov <anton@redhat.com>
This commit is contained in:
Oleg Nesterov 2013-03-29 18:26:51 +01:00
parent 0e3853d202
commit 457d1772f1
2 changed files with 36 additions and 31 deletions
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5
kernel/trace/trace.h
View file

@ -103,11 +103,6 @@ struct kretprobe_trace_entry_head {
unsigned long ret_ip;
};
struct uprobe_trace_entry_head {
struct trace_entry ent;
unsigned long ip;
};
/*
* trace_flag_type is an enumeration that holds different
* states when a trace occurs. These are:

62
kernel/trace/trace_uprobe.c
View file

@ -28,6 +28,18 @@
#define UPROBE_EVENT_SYSTEM "uprobes"
struct uprobe_trace_entry_head {
struct trace_entry ent;
unsigned long vaddr[];
};
#define SIZEOF_TRACE_ENTRY(is_return) \
(sizeof(struct uprobe_trace_entry_head) + \
sizeof(unsigned long) * (is_return ? 2 : 1))
#define DATAOF_TRACE_ENTRY(entry, is_return) \
((void*)(entry) + SIZEOF_TRACE_ENTRY(is_return))
struct trace_uprobe_filter {
rwlock_t rwlock;
int nr_systemwide;
@ -491,20 +503,19 @@ static int uprobe_trace_func(struct trace_uprobe *tu, struct pt_regs *regs)
struct uprobe_trace_entry_head *entry;
struct ring_buffer_event *event;
struct ring_buffer *buffer;
u8 *data;
void *data;
int size, i;
struct ftrace_event_call *call = &tu->call;
size = sizeof(*entry) + tu->size;
size = SIZEOF_TRACE_ENTRY(false) + tu->size;
event = trace_current_buffer_lock_reserve(&buffer, call->event.type,
size, 0, 0);
if (!event)
return 0;
entry = ring_buffer_event_data(event);
entry->ip = instruction_pointer(regs);
data = (u8 *)&entry[1];
entry->vaddr[0] = instruction_pointer(regs);
data = DATAOF_TRACE_ENTRY(entry, false);
for (i = 0; i < tu->nr_args; i++)
call_fetch(&tu->args[i].fetch, regs, data + tu->args[i].offset);
@ -518,22 +529,22 @@ static int uprobe_trace_func(struct trace_uprobe *tu, struct pt_regs *regs)
static enum print_line_t
print_uprobe_event(struct trace_iterator *iter, int flags, struct trace_event *event)
{
struct uprobe_trace_entry_head *field;
struct uprobe_trace_entry_head *entry;
struct trace_seq *s = &iter->seq;
struct trace_uprobe *tu;
u8 *data;
int i;
field = (struct uprobe_trace_entry_head *)iter->ent;
entry = (struct uprobe_trace_entry_head *)iter->ent;
tu = container_of(event, struct trace_uprobe, call.event);
if (!trace_seq_printf(s, "%s: (0x%lx)", tu->call.name, field->ip))
if (!trace_seq_printf(s, "%s: (0x%lx)", tu->call.name, entry->vaddr[0]))
goto partial;
data = (u8 *)&field[1];
data = DATAOF_TRACE_ENTRY(entry, false);
for (i = 0; i < tu->nr_args; i++) {
if (!tu->args[i].type->print(s, tu->args[i].name,
data + tu->args[i].offset, field))
data + tu->args[i].offset, entry))
goto partial;
}
@ -585,16 +596,17 @@ static void probe_event_disable(struct trace_uprobe *tu, int flag)
static int uprobe_event_define_fields(struct ftrace_event_call *event_call)
{
int ret, i;
int ret, i, size;
struct uprobe_trace_entry_head field;
struct trace_uprobe *tu = (struct trace_uprobe *)event_call->data;
struct trace_uprobe *tu = event_call->data;
DEFINE_FIELD(unsigned long, ip, FIELD_STRING_IP, 0);
DEFINE_FIELD(unsigned long, vaddr[0], FIELD_STRING_IP, 0);
size = SIZEOF_TRACE_ENTRY(false);
/* Set argument names as fields */
for (i = 0; i < tu->nr_args; i++) {
ret = trace_define_field(event_call, tu->args[i].type->fmttype,
tu->args[i].name,
sizeof(field) + tu->args[i].offset,
size + tu->args[i].offset,
tu->args[i].type->size,
tu->args[i].type->is_signed,
FILTER_OTHER);
@ -748,33 +760,31 @@ static int uprobe_perf_func(struct trace_uprobe *tu, struct pt_regs *regs)
struct ftrace_event_call *call = &tu->call;
struct uprobe_trace_entry_head *entry;
struct hlist_head *head;
u8 *data;
int size, __size, i;
int rctx;
unsigned long ip;
void *data;
int size, rctx, i;
if (!uprobe_perf_filter(&tu->consumer, 0, current->mm))
return UPROBE_HANDLER_REMOVE;
__size = sizeof(*entry) + tu->size;
size = ALIGN(__size + sizeof(u32), sizeof(u64));
size -= sizeof(u32);
size = SIZEOF_TRACE_ENTRY(false);
size = ALIGN(size + tu->size + sizeof(u32), sizeof(u64)) - sizeof(u32);
if (WARN_ONCE(size > PERF_MAX_TRACE_SIZE, "profile buffer not large enough"))
return 0;
preempt_disable();
entry = perf_trace_buf_prepare(size, call->event.type, regs, &rctx);
if (!entry)
goto out;
entry->ip = instruction_pointer(regs);
data = (u8 *)&entry[1];
ip = instruction_pointer(regs);
entry->vaddr[0] = ip;
data = DATAOF_TRACE_ENTRY(entry, false);
for (i = 0; i < tu->nr_args; i++)
call_fetch(&tu->args[i].fetch, regs, data + tu->args[i].offset);
head = this_cpu_ptr(call->perf_events);
perf_trace_buf_submit(entry, size, rctx, entry->ip, 1, regs, head, NULL);
perf_trace_buf_submit(entry, size, rctx, ip, 1, regs, head, NULL);
out:
preempt_enable();
return 0;
@ -784,7 +794,7 @@ static int uprobe_perf_func(struct trace_uprobe *tu, struct pt_regs *regs)
static
int trace_uprobe_register(struct ftrace_event_call *event, enum trace_reg type, void *data)
{
struct trace_uprobe *tu = (struct trace_uprobe *)event->data;
struct trace_uprobe *tu = event->data;
switch (type) {
case TRACE_REG_REGISTER: