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trace: avoid pointer aliasing in trace_record_finish()

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Declaring a TraceRecord on the stack works fine.  No need for a
uint8_t array and pointer aliasing.

Signed-off-by: Harsh Prateek Bora <harsh@linux.vnet.ibm.com>
Signed-off-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
This commit is contained in:
Harsh Prateek Bora 2012-07-20 18:52:15 +05:30 committed by Stefan Hajnoczi
parent fd82f015a1
commit db8894f209
1 changed files with 4 additions and 5 deletions
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9
trace/simple.c
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@ -269,12 +269,11 @@ static unsigned int write_to_buffer(unsigned int idx, void *dataptr, size_t size
void trace_record_finish(TraceBufferRecord *rec)
{
uint8_t temp_rec[sizeof(TraceRecord)];
TraceRecord *record = (TraceRecord *) temp_rec;
read_from_buffer(rec->tbuf_idx, temp_rec, sizeof(TraceRecord));
TraceRecord record;
read_from_buffer(rec->tbuf_idx, &record, sizeof(TraceRecord));
smp_wmb(); /* write barrier before marking as valid */
record->event |= TRACE_RECORD_VALID;
write_to_buffer(rec->tbuf_idx, temp_rec, sizeof(TraceRecord));
record.event |= TRACE_RECORD_VALID;
write_to_buffer(rec->tbuf_idx, &record, sizeof(TraceRecord));
if ((trace_idx - writeout_idx) > TRACE_BUF_FLUSH_THRESHOLD) {
flush_trace_file(false);