Commit db8894f2 authored by Harsh Prateek Bora's avatar Harsh Prateek Bora Committed by Stefan Hajnoczi
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trace: avoid pointer aliasing in trace_record_finish() 



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

Signed-off-by: default avatarHarsh Prateek Bora <harsh@linux.vnet.ibm.com>
Signed-off-by: default avatarStefan Hajnoczi <stefanha@linux.vnet.ibm.com>
parent fd82f015

trace/simple.c

+4 −5
Original line number Diff line number Diff line
@@ -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);