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trace: Direct access of atomics is verboten, use the API

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The GLib Reference Manual says:

    It is very important that all accesses to a particular integer or
    pointer be performed using only this API and that different sizes
    of operation are not mixed or used on overlapping memory
    regions. Never read or assign directly from or to a value --
    always use this API.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Harsh Prateek Bora <harsh@linux.vnet.ibm.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
This commit is contained in:
Markus Armbruster 2013-01-25 16:43:38 +01:00 committed by Stefan Hajnoczi
parent fb3a508531
commit e722d705ae
1 changed files with 5 additions and 4 deletions
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9
trace/simple.c
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@ -166,13 +166,13 @@ static gpointer writeout_thread(gpointer opaque)
for (;;) {
wait_for_trace_records_available();
if (dropped_events) {
if (g_atomic_int_get(&dropped_events)) {
dropped.rec.event = DROPPED_EVENT_ID,
dropped.rec.timestamp_ns = get_clock();
dropped.rec.length = sizeof(TraceRecord) + sizeof(uint64_t),
dropped.rec.reserved = 0;
while (1) {
dropped_count = dropped_events;
dropped_count = g_atomic_int_get(&dropped_events);
if (g_atomic_int_compare_and_exchange(&dropped_events,
dropped_count, 0)) {
break;
@ -214,7 +214,7 @@ int trace_record_start(TraceBufferRecord *rec, TraceEventID event, size_t datasi
uint64_t timestamp_ns = get_clock();
while (1) {
old_idx = trace_idx;
old_idx = g_atomic_int_get(&trace_idx);
smp_rmb();
new_idx = old_idx + rec_len;
@ -275,7 +275,8 @@ void trace_record_finish(TraceBufferRecord *rec)
record.event |= TRACE_RECORD_VALID;
write_to_buffer(rec->tbuf_idx, &record, sizeof(TraceRecord));
if ((trace_idx - writeout_idx) > TRACE_BUF_FLUSH_THRESHOLD) {
if ((g_atomic_int_get(&trace_idx) - writeout_idx)
> TRACE_BUF_FLUSH_THRESHOLD) {
flush_trace_file(false);
}
}