Commit cd92bf61 authored by Oleg Nesterov's avatar Oleg Nesterov Committed by Steven Rostedt
Browse files

tracing/perf: Move the PERF_MAX_TRACE_SIZE check into perf_trace_buf_prepare() 

Every perf_trace_buf_prepare() caller does
WARN_ONCE(size > PERF_MAX_TRACE_SIZE, message) and "message" is
almost the same.

Shift this WARN_ONCE() into perf_trace_buf_prepare(). This changes
the meaning of _ONCE, but I think this is fine.

	- 4947014 2932448 10104832  17984294  1126b26 vmlinux
	+ 4948422 2932448 10104832  17985702  11270a6 vmlinux

on my build.

Link: http://lkml.kernel.org/r/20130617170211.GA19813@redhat.com



Acked-by: default avatarPeter Zijlstra <peterz@infradead.org>
Signed-off-by: default avatarOleg Nesterov <oleg@redhat.com>
Signed-off-by: default avatarSteven Rostedt <rostedt@goodmis.org>
parent 421c7860

include/trace/ftrace.h

+0 −4
Original line number Diff line number Diff line
@@ -670,10 +670,6 @@ perf_trace_##call(void *__data, proto) \ 
			     sizeof(u64));				\

	__entry_size -= sizeof(u32);					\

									\

	if (WARN_ONCE(__entry_size > PERF_MAX_TRACE_SIZE,		\

		      "profile buffer not large enough"))		\

		return;							\

									\

	entry = (struct ftrace_raw_##call *)perf_trace_buf_prepare(	\

		__entry_size, event_call->event.type, &__regs, &rctx);	\

	if (!entry)							\

kernel/trace/trace_event_perf.c

+4 −0
Original line number Diff line number Diff line
@@ -236,6 +236,10 @@ __kprobes void *perf_trace_buf_prepare(int size, unsigned short type, 


	BUILD_BUG_ON(PERF_MAX_TRACE_SIZE % sizeof(unsigned long));



	if (WARN_ONCE(size > PERF_MAX_TRACE_SIZE,

			"perf buffer not large enough"))

		return NULL;



	pc = preempt_count();



	*rctxp = perf_swevent_get_recursion_context();

kernel/trace/trace_kprobe.c

+0 −6
Original line number Diff line number Diff line
@@ -1087,9 +1087,6 @@ kprobe_perf_func(struct trace_probe *tp, struct pt_regs *regs) 
	__size = sizeof(*entry) + tp->size + dsize;

	size = ALIGN(__size + sizeof(u32), sizeof(u64));

	size -= sizeof(u32);

	if (WARN_ONCE(size > PERF_MAX_TRACE_SIZE,

		     "profile buffer not large enough"))

		return;



	entry = perf_trace_buf_prepare(size, call->event.type, regs, &rctx);

	if (!entry)
@@ -1120,9 +1117,6 @@ kretprobe_perf_func(struct trace_probe *tp, struct kretprobe_instance *ri, 
	__size = sizeof(*entry) + tp->size + dsize;

	size = ALIGN(__size + sizeof(u32), sizeof(u64));

	size -= sizeof(u32);

	if (WARN_ONCE(size > PERF_MAX_TRACE_SIZE,

		     "profile buffer not large enough"))

		return;



	entry = perf_trace_buf_prepare(size, call->event.type, regs, &rctx);

	if (!entry)

kernel/trace/trace_syscalls.c

+0 −12
Original line number Diff line number Diff line
@@ -575,10 +575,6 @@ static void perf_syscall_enter(void *ignore, struct pt_regs *regs, long id) 
	size = ALIGN(size + sizeof(u32), sizeof(u64));

	size -= sizeof(u32);



	if (WARN_ONCE(size > PERF_MAX_TRACE_SIZE,

		      "perf buffer not large enough"))

		return;



	rec = (struct syscall_trace_enter *)perf_trace_buf_prepare(size,

				sys_data->enter_event->event.type, regs, &rctx);

	if (!rec)
@@ -652,14 +648,6 @@ static void perf_syscall_exit(void *ignore, struct pt_regs *regs, long ret) 
	size = ALIGN(sizeof(*rec) + sizeof(u32), sizeof(u64));

	size -= sizeof(u32);



	/*

	 * Impossible, but be paranoid with the future

	 * How to put this check outside runtime?

	 */

	if (WARN_ONCE(size > PERF_MAX_TRACE_SIZE,

		"exit event has grown above perf buffer size"))

		return;



	rec = (struct syscall_trace_exit *)perf_trace_buf_prepare(size,

				sys_data->exit_event->event.type, regs, &rctx);

	if (!rec)

kernel/trace/trace_uprobe.c

+0 −2
Original line number Diff line number Diff line
@@ -818,8 +818,6 @@ static void uprobe_perf_print(struct trace_uprobe *tu, 


	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;



	preempt_disable();

	head = this_cpu_ptr(call->perf_events);

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