aboutsummaryrefslogtreecommitdiffstats
path: root/block
diff options
context:
space:
mode:
authorArnaldo Carvalho de Melo <acme@redhat.com>2009-02-05 16:14:13 -0200
committerIngo Molnar <mingo@elte.hu>2009-02-06 01:01:41 +0100
commit51a763dd84253bab1d0a1e68e11a7753d1b702ca (patch)
tree2cc2cf0509db480391c585786285267e360c1338 /block
parent0a9877514c4fed10a70720293b37213dd172ee3e (diff)
downloadmrst-s0i3-test-51a763dd84253bab1d0a1e68e11a7753d1b702ca.tar.gz
mrst-s0i3-test-51a763dd84253bab1d0a1e68e11a7753d1b702ca.tar.xz
mrst-s0i3-test-51a763dd84253bab1d0a1e68e11a7753d1b702ca.zip
tracing: Introduce trace_buffer_{lock_reserve,unlock_commit}
Impact: new API These new functions do what previously was being open coded, reducing the number of details ftrace plugin writers have to worry about. It also standardizes the handling of stacktrace, userstacktrace and other trace options we may introduce in the future. With this patch, for instance, the blk tracer (and some others already in the tree) can use the "userstacktrace" /d/tracing/trace_options facility. $ codiff /tmp/vmlinux.before /tmp/vmlinux.after linux-2.6-tip/kernel/trace/trace.c: trace_vprintk | -5 trace_graph_return | -22 trace_graph_entry | -26 trace_function | -45 __ftrace_trace_stack | -27 ftrace_trace_userstack | -29 tracing_sched_switch_trace | -66 tracing_stop | +1 trace_seq_to_user | -1 ftrace_trace_special | -63 ftrace_special | +1 tracing_sched_wakeup_trace | -70 tracing_reset_online_cpus | -1 13 functions changed, 2 bytes added, 355 bytes removed, diff: -353 linux-2.6-tip/block/blktrace.c: __blk_add_trace | -58 1 function changed, 58 bytes removed, diff: -58 linux-2.6-tip/kernel/trace/trace.c: trace_buffer_lock_reserve | +88 trace_buffer_unlock_commit | +86 2 functions changed, 174 bytes added, diff: +174 /tmp/vmlinux.after: 16 functions changed, 176 bytes added, 413 bytes removed, diff: -237 Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Acked-by: Frédéric Weisbecker <fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
Diffstat (limited to 'block')
-rw-r--r--block/blktrace.c21
1 files changed, 6 insertions, 15 deletions
diff --git a/block/blktrace.c b/block/blktrace.c
index 8e52f24cc8f..834cd84037b 100644
--- a/block/blktrace.c
+++ b/block/blktrace.c
@@ -187,19 +187,15 @@ static void __blk_add_trace(struct blk_trace *bt, sector_t sector, int bytes,
cpu = raw_smp_processor_id();
if (blk_tr) {
- struct trace_entry *ent;
tracing_record_cmdline(current);
- event = ring_buffer_lock_reserve(blk_tr->buffer,
- sizeof(*t) + pdu_len);
+ pc = preempt_count();
+ event = trace_buffer_lock_reserve(blk_tr, TRACE_BLK,
+ sizeof(*t) + pdu_len,
+ 0, pc);
if (!event)
return;
-
- ent = ring_buffer_event_data(event);
- t = (struct blk_io_trace *)ent;
- pc = preempt_count();
- tracing_generic_entry_update(ent, 0, pc);
- ent->type = TRACE_BLK;
+ t = ring_buffer_event_data(event);
goto record_it;
}
@@ -241,12 +237,7 @@ record_it:
memcpy((void *) t + sizeof(*t), pdu_data, pdu_len);
if (blk_tr) {
- ring_buffer_unlock_commit(blk_tr->buffer, event);
- if (pid != 0 &&
- !(blk_tracer_flags.val & TRACE_BLK_OPT_CLASSIC) &&
- (trace_flags & TRACE_ITER_STACKTRACE) != 0)
- __trace_stack(blk_tr, 0, 5, pc);
- trace_wake_up();
+ trace_buffer_unlock_commit(blk_tr, event, 0, pc);
return;
}
}