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: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
diff --git a/kernel/trace/trace_event_perf.c b/kernel/trace/trace_event_perf.c
index 12df557..80c36bc 100644
--- a/kernel/trace/trace_event_perf.c
+++ b/kernel/trace/trace_event_perf.c
@@ -236,6 +236,10 @@
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();
diff --git a/kernel/trace/trace_kprobe.c b/kernel/trace/trace_kprobe.c
index 7ed6976..ae6ce83 100644
--- a/kernel/trace/trace_kprobe.c
+++ b/kernel/trace/trace_kprobe.c
@@ -1087,9 +1087,6 @@
__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 @@
__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)
diff --git a/kernel/trace/trace_syscalls.c b/kernel/trace/trace_syscalls.c
index ac00857..8fd0365 100644
--- a/kernel/trace/trace_syscalls.c
+++ b/kernel/trace/trace_syscalls.c
@@ -575,10 +575,6 @@
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 @@
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)
diff --git a/kernel/trace/trace_uprobe.c b/kernel/trace/trace_uprobe.c
index d5d0cd3..a23d2d7 100644
--- a/kernel/trace/trace_uprobe.c
+++ b/kernel/trace/trace_uprobe.c
@@ -818,8 +818,6 @@
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);