Luck, Tony wrote:
It is very much curious having so few dirty and i-access traps...Your data collection code has races (ld8, add, st8 on one cpu can race with another cpu doing the same). So you'll undercount whenever a race happens. Perhaps you should use per-cpu counters to collect the values, and then sum for each cpu in the syscall() before reporting to the user?
It was not very important to count the events precisely. The lesson I learnt is the VHPT miss handler is the most important (maybe the D-ACCESS trap handler), the others are "neglectable". (I have not counted yet the handlers not doing a purge.) The problem is that the most frequently used trap handler contains the unsafe walk of the rx = IA64_KR_PT_BASE -> pgd[i] -> pud[j] -> pmd[k] -> pte[l] chain... Zoltan - : send the line "unsubscribe linux-ia64" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
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