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Fix message priority implementation

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Functional specification mandates returning a message with a higher
timestamp in case two messages have the same priority. Somehow we
missed this in the implementation. This also introduced a bug where
all messages with same priority could cause problems.
This commit is contained in:
Sanchayan Maity 2016-03-19 16:54:26 +05:30
parent fe71ea4bc1
commit 0cc443d3c2
1 changed files with 4 additions and 1 deletions
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5
minix/kernel/mqueue.c
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@ -176,7 +176,10 @@ int message_index_with_highprio(int mqdes, endpoint_t dst)
prio = mq.msg[mqdes].msge[i].priority;
for (int j = 0; j < MAX_RECEIVERS; j++) {
if (mq.msg[mqdes].msge[i].dst[j] == dst) {
if (max_prio < find_max(max_prio, prio)) {
if (max_prio == prio) {
if (mq.msg[mqdes].msge[i].timestamp > mq.msg[mqdes].msge[index].timestamp)
index = i;
} else if (max_prio < find_max(max_prio, prio)) {
index = i;
max_prio = find_max(max_prio, prio);
}