From 1b22e382ab40b0e3ee5abb3e310dffb16fee22aa Mon Sep 17 00:00:00 2001 From: "Steven Rostedt (Red Hat)" Date: Sat, 9 Mar 2013 00:56:08 -0500 Subject: [PATCH] tracing: Let tracing_snapshot() be used by modules but not NMI Add EXPORT_SYMBOL_GPL() to let the tracing_snapshot() functions be called from modules. Also add a test to see if the snapshot was called from NMI context and just warn in the tracing buffer if so, and return. Signed-off-by: Steven Rostedt --- kernel/trace/trace.c | 10 ++++++++++ 1 file changed, 10 insertions(+) diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index d372c6504c99..5c53e4092269 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -442,6 +442,12 @@ void tracing_snapshot(void) struct tracer *tracer = tr->current_trace; unsigned long flags; + if (in_nmi()) { + internal_trace_puts("*** SNAPSHOT CALLED FROM NMI CONTEXT ***\n"); + internal_trace_puts("*** snapshot is being ignored ***\n"); + return; + } + if (!tr->allocated_snapshot) { internal_trace_puts("*** SNAPSHOT NOT ALLOCATED ***\n"); internal_trace_puts("*** stopping trace here! ***\n"); @@ -460,6 +466,7 @@ void tracing_snapshot(void) update_max_tr(tr, current, smp_processor_id()); local_irq_restore(flags); } +EXPORT_SYMBOL_GPL(tracing_snapshot); static int resize_buffer_duplicate_size(struct trace_buffer *trace_buf, struct trace_buffer *size_buf, int cpu_id); @@ -493,16 +500,19 @@ void tracing_snapshot_alloc(void) tracing_snapshot(); } +EXPORT_SYMBOL_GPL(tracing_snapshot_alloc); #else void tracing_snapshot(void) { WARN_ONCE(1, "Snapshot feature not enabled, but internal snapshot used"); } +EXPORT_SYMBOL_GPL(tracing_snapshot); void tracing_snapshot_alloc(void) { /* Give warning */ tracing_snapshot(); } +EXPORT_SYMBOL_GPL(tracing_snapshot_alloc); #endif /* CONFIG_TRACER_SNAPSHOT */ /** -- 2.20.1