summaryrefslogtreecommitdiffstats
path: root/include/linux/ring_buffer.h
diff options
context:
space:
mode:
authorSebastian Andrzej Siewior <bigeasy@linutronix.de>2016-11-27 00:13:34 +0100
committerThomas Gleixner <tglx@linutronix.de>2016-12-02 00:52:34 +0100
commitb32614c03413f8a6025d8677c2b7c0ee976e63d4 (patch)
tree31033ddc3ce2320c4f4faec012b7bfec6199b550 /include/linux/ring_buffer.h
parent14660b7ea3ca628410bb999d53926ca77973892b (diff)
downloadlinux-stable-b32614c03413f8a6025d8677c2b7c0ee976e63d4.tar.gz
linux-stable-b32614c03413f8a6025d8677c2b7c0ee976e63d4.tar.bz2
linux-stable-b32614c03413f8a6025d8677c2b7c0ee976e63d4.zip
tracing/rb: Convert to hotplug state machine
Install the callbacks via the state machine. The notifier in struct ring_buffer is replaced by the multi instance interface. Upon __ring_buffer_alloc() invocation, cpuhp_state_add_instance() will invoke the trace_rb_cpu_prepare() on each CPU. This callback may now fail. This means __ring_buffer_alloc() will fail and cleanup (like previously) and during a CPU up event this failure will not allow the CPU to come up. Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: rt@linutronix.de Link: http://lkml.kernel.org/r/20161126231350.10321-7-bigeasy@linutronix.de Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Diffstat (limited to 'include/linux/ring_buffer.h')
-rw-r--r--include/linux/ring_buffer.h6
1 files changed, 6 insertions, 0 deletions
diff --git a/include/linux/ring_buffer.h b/include/linux/ring_buffer.h
index 4acc552e9279..b6d4568795a7 100644
--- a/include/linux/ring_buffer.h
+++ b/include/linux/ring_buffer.h
@@ -198,4 +198,10 @@ enum ring_buffer_flags {
RB_FL_OVERWRITE = 1 << 0,
};
+#ifdef CONFIG_RING_BUFFER
+int trace_rb_cpu_prepare(unsigned int cpu, struct hlist_node *node);
+#else
+#define trace_rb_cpu_prepare NULL
+#endif
+
#endif /* _LINUX_RING_BUFFER_H */