Commit 393a736c authored by Oleg Nesterov's avatar Oleg Nesterov
Browse files

uprobes/tracing: Make uprobe_{trace,perf}_print() uretprobe-friendly 



Change uprobe_trace_print() and uprobe_perf_print() to check
is_ret_probe() and fill ring_buffer_event accordingly.

Also change uprobe_trace_func() and uprobe_perf_func() to not
_print() if is_ret_probe() is true. Note that we keep ->handler()
nontrivial even for uretprobe, we need this for filtering and for
other potential extensions.

Signed-off-by: default avatarOleg Nesterov <oleg@redhat.com>
Acked-by: default avatarSrikar Dronamraju <srikar@linux.vnet.ibm.com>
Tested-by: default avatarAnton Arapov <anton@redhat.com>
parent c1ae5c75

kernel/trace/trace_uprobe.c

+25 −9
Original line number Diff line number Diff line
@@ -516,15 +516,22 @@ static void uprobe_trace_print(struct trace_uprobe *tu, 
	int size, i;

	struct ftrace_event_call *call = &tu->call;



	size = SIZEOF_TRACE_ENTRY(false) + tu->size;

	size = SIZEOF_TRACE_ENTRY(is_ret_probe(tu));

	event = trace_current_buffer_lock_reserve(&buffer, call->event.type,

						  size, 0, 0);

						  size + tu->size, 0, 0);

	if (!event)

		return;



	entry = ring_buffer_event_data(event);

	if (is_ret_probe(tu)) {

		entry->vaddr[0] = func;

		entry->vaddr[1] = instruction_pointer(regs);

		data = DATAOF_TRACE_ENTRY(entry, true);

	} else {

		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);
@@ -535,6 +542,7 @@ static void uprobe_trace_print(struct trace_uprobe *tu, 
/* uprobe handler */

static int uprobe_trace_func(struct trace_uprobe *tu, struct pt_regs *regs)

{

	if (!is_ret_probe(tu))

		uprobe_trace_print(tu, 0, regs);

	return 0;

}
@@ -784,7 +792,7 @@ static void uprobe_perf_print(struct trace_uprobe *tu, 
	void *data;

	int size, rctx, i;



	size = SIZEOF_TRACE_ENTRY(false);

	size = SIZEOF_TRACE_ENTRY(is_ret_probe(tu));

	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;
@@ -795,8 +803,15 @@ static void uprobe_perf_print(struct trace_uprobe *tu, 
		goto out;



	ip = instruction_pointer(regs);

	if (is_ret_probe(tu)) {

		entry->vaddr[0] = func;

		entry->vaddr[1] = ip;

		data = DATAOF_TRACE_ENTRY(entry, true);

	} else {

		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);
@@ -812,6 +827,7 @@ static int uprobe_perf_func(struct trace_uprobe *tu, struct pt_regs *regs) 
	if (!uprobe_perf_filter(&tu->consumer, 0, current->mm))

		return UPROBE_HANDLER_REMOVE;



	if (!is_ret_probe(tu))

		uprobe_perf_print(tu, 0, regs);

	return 0;

}

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