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authorLinus Torvalds <torvalds@linux-foundation.org>2008-10-20 13:35:07 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2008-10-20 13:35:07 -0700
commit92b29b86fe2e183d44eb467e5e74a5f718ef2e43 (patch)
tree1bac8a1aa11d47322b66d10ec3a370016d843d06 /include/linux/ring_buffer.h
parentb9d7ccf56be1ac77b71a284a1c0e6337f9a7aff0 (diff)
parent98d9c66ab07471006fd7910cb16453581c41a3e7 (diff)
Merge branch 'tracing-v28-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'tracing-v28-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (131 commits) tracing/fastboot: improve help text tracing/stacktrace: improve help text tracing/fastboot: fix initcalls disposition in bootgraph.pl tracing/fastboot: fix bootgraph.pl initcall name regexp tracing/fastboot: fix issues and improve output of bootgraph.pl tracepoints: synchronize unregister static inline tracepoints: tracepoint_synchronize_unregister() ftrace: make ftrace_test_p6nop disassembler-friendly markers: fix synchronize marker unregister static inline tracing/fastboot: add better resolution to initcall debug/tracing trace: add build-time check to avoid overrunning hex buffer ftrace: fix hex output mode of ftrace tracing/fastboot: fix initcalls disposition in bootgraph.pl tracing/fastboot: fix printk format typo in boot tracer ftrace: return an error when setting a nonexistent tracer ftrace: make some tracers reentrant ring-buffer: make reentrant ring-buffer: move page indexes into page headers tracing/fastboot: only trace non-module initcalls ftrace: move pc counter in irqtrace ... Manually fix conflicts: - init/main.c: initcall tracing - kernel/module.c: verbose level vs tracepoints - scripts/bootgraph.pl: fallout from cherry-picking commits.
Diffstat (limited to 'include/linux/ring_buffer.h')
-rw-r--r--include/linux/ring_buffer.h127
1 files changed, 127 insertions, 0 deletions
diff --git a/include/linux/ring_buffer.h b/include/linux/ring_buffer.h
new file mode 100644
index 00000000000..536b0ca46a0
--- /dev/null
+++ b/include/linux/ring_buffer.h
@@ -0,0 +1,127 @@
+#ifndef _LINUX_RING_BUFFER_H
+#define _LINUX_RING_BUFFER_H
+
+#include <linux/mm.h>
+#include <linux/seq_file.h>
+
+struct ring_buffer;
+struct ring_buffer_iter;
+
+/*
+ * Don't reference this struct directly, use functions below.
+ */
+struct ring_buffer_event {
+ u32 type:2, len:3, time_delta:27;
+ u32 array[];
+};
+
+/**
+ * enum ring_buffer_type - internal ring buffer types
+ *
+ * @RINGBUF_TYPE_PADDING: Left over page padding
+ * array is ignored
+ * size is variable depending on how much
+ * padding is needed
+ *
+ * @RINGBUF_TYPE_TIME_EXTEND: Extend the time delta
+ * array[0] = time delta (28 .. 59)
+ * size = 8 bytes
+ *
+ * @RINGBUF_TYPE_TIME_STAMP: Sync time stamp with external clock
+ * array[0] = tv_nsec
+ * array[1] = tv_sec
+ * size = 16 bytes
+ *
+ * @RINGBUF_TYPE_DATA: Data record
+ * If len is zero:
+ * array[0] holds the actual length
+ * array[1..(length+3)/4-1] holds data
+ * else
+ * length = len << 2
+ * array[0..(length+3)/4] holds data
+ */
+enum ring_buffer_type {
+ RINGBUF_TYPE_PADDING,
+ RINGBUF_TYPE_TIME_EXTEND,
+ /* FIXME: RINGBUF_TYPE_TIME_STAMP not implemented */
+ RINGBUF_TYPE_TIME_STAMP,
+ RINGBUF_TYPE_DATA,
+};
+
+unsigned ring_buffer_event_length(struct ring_buffer_event *event);
+void *ring_buffer_event_data(struct ring_buffer_event *event);
+
+/**
+ * ring_buffer_event_time_delta - return the delta timestamp of the event
+ * @event: the event to get the delta timestamp of
+ *
+ * The delta timestamp is the 27 bit timestamp since the last event.
+ */
+static inline unsigned
+ring_buffer_event_time_delta(struct ring_buffer_event *event)
+{
+ return event->time_delta;
+}
+
+/*
+ * size is in bytes for each per CPU buffer.
+ */
+struct ring_buffer *
+ring_buffer_alloc(unsigned long size, unsigned flags);
+void ring_buffer_free(struct ring_buffer *buffer);
+
+int ring_buffer_resize(struct ring_buffer *buffer, unsigned long size);
+
+struct ring_buffer_event *
+ring_buffer_lock_reserve(struct ring_buffer *buffer,
+ unsigned long length,
+ unsigned long *flags);
+int ring_buffer_unlock_commit(struct ring_buffer *buffer,
+ struct ring_buffer_event *event,
+ unsigned long flags);
+int ring_buffer_write(struct ring_buffer *buffer,
+ unsigned long length, void *data);
+
+struct ring_buffer_event *
+ring_buffer_peek(struct ring_buffer *buffer, int cpu, u64 *ts);
+struct ring_buffer_event *
+ring_buffer_consume(struct ring_buffer *buffer, int cpu, u64 *ts);
+
+struct ring_buffer_iter *
+ring_buffer_read_start(struct ring_buffer *buffer, int cpu);
+void ring_buffer_read_finish(struct ring_buffer_iter *iter);
+
+struct ring_buffer_event *
+ring_buffer_iter_peek(struct ring_buffer_iter *iter, u64 *ts);
+struct ring_buffer_event *
+ring_buffer_read(struct ring_buffer_iter *iter, u64 *ts);
+void ring_buffer_iter_reset(struct ring_buffer_iter *iter);
+int ring_buffer_iter_empty(struct ring_buffer_iter *iter);
+
+unsigned long ring_buffer_size(struct ring_buffer *buffer);
+
+void ring_buffer_reset_cpu(struct ring_buffer *buffer, int cpu);
+void ring_buffer_reset(struct ring_buffer *buffer);
+
+int ring_buffer_swap_cpu(struct ring_buffer *buffer_a,
+ struct ring_buffer *buffer_b, int cpu);
+
+int ring_buffer_empty(struct ring_buffer *buffer);
+int ring_buffer_empty_cpu(struct ring_buffer *buffer, int cpu);
+
+void ring_buffer_record_disable(struct ring_buffer *buffer);
+void ring_buffer_record_enable(struct ring_buffer *buffer);
+void ring_buffer_record_disable_cpu(struct ring_buffer *buffer, int cpu);
+void ring_buffer_record_enable_cpu(struct ring_buffer *buffer, int cpu);
+
+unsigned long ring_buffer_entries(struct ring_buffer *buffer);
+unsigned long ring_buffer_overruns(struct ring_buffer *buffer);
+
+u64 ring_buffer_time_stamp(int cpu);
+void ring_buffer_normalize_time_stamp(int cpu, u64 *ts);
+
+enum ring_buffer_flags {
+ RB_FL_OVERWRITE = 1 << 0,
+};
+
+#endif /* _LINUX_RING_BUFFER_H */