1 /* Copyright (c) 2013 The Regents of the University of California
2 * Barret Rhoden <brho@cs.berkeley.edu>
3 * See LICENSE for details.
5 * Simple ring-buffer tracing for in-kernel events. */
11 void trace_ring_init(struct trace_ring *tr, void *buf, size_t buf_size,
15 tr->tr_buf_sz = buf_size;
16 tr->tr_event_sz_shift = LOG2_UP(event_size);
17 tr->tr_max = (1 << LOG2_DOWN(buf_size / (1 << tr->tr_event_sz_shift)));
18 printd("Initializing TR with %d elements of shift %d (%d)\n",
19 tr->tr_max, tr->tr_event_sz_shift, (1 << tr->tr_event_sz_shift));
20 trace_ring_reset_and_clear(tr);
23 void trace_ring_reset(struct trace_ring *tr)
28 void trace_ring_reset_and_clear(struct trace_ring *tr)
30 memset(tr->tr_buf, 0, tr->tr_buf_sz);
34 void trace_ring_foreach(struct trace_ring *tr, trace_handler_t tr_func,
37 for (int i = 0; i < tr->tr_max; i++)
38 tr_func(__get_tr_slot(tr, i), data);