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# try to induce overflow of pmap aggregation
# (this will only work on smp machines)
global stat, count, pcpu_count, max_count
probe begin {
if (num_online_cpus() < 2) {
warn("This test only applies to smp systems...")
exit()
}
max_count = max_map_entries() + 1
}
probe kernel.function("scheduler_tick") {
# Be sure not to overflow the percpu array
if (++pcpu_count[cpu()] > max_map_entries())
next
i = ++count
if (i <= max_count)
stat[i] <<< i
else
exit()
}
probe end {
# pmap aggregation should overflow here
foreach (i in stat)
printf("@count(stat[%d]) = %d\n", i, @count(stat[i]))
}
probe end {
# sorted pmap aggregation should overflow here
foreach (i+ in stat)
printf("@count(stat[%d]) = %d\n", i, @count(stat[i]))
}
function max_map_entries:long() %{
STAP_RETVALUE = MAXMAPENTRIES;
%}
function num_online_cpus:long() %{
STAP_RETVALUE = num_online_cpus();
%}
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