discuss marker types

git-svn-id: http://ltt.polymtl.ca/svn@2398 04897980-b3bd-0310-b5e0-8ef037075253

diff --git a/ltt/branches/poly/doc/developer/time-monotonic-accurate.txt b/ltt/branches/poly/doc/developer/time-monotonic-accurate.txt
index c1bc89d4d267a9a13550c056f42d943728c9e947..2fb657e49aa0c60eef946ee32b728182a0bc0646 100644 (file)
--- a/ltt/branches/poly/doc/developer/time-monotonic-accurate.txt
+++ b/ltt/branches/poly/doc/developer/time-monotonic-accurate.txt
@@ -84,20 +84,26 @@ wake_from_hlt()
  * This would happen if we are scheduled out for a period of time long enough to
  * permit 2 frequency changes. We simply start the loop again if it happens.
  * We detect it by comparing the update_count running counter. */
+/* FIXME : if thread is migrated to another CPU, get_cycles() is bad */
+/* Pb with get cpu id / migrate / get_cycles() / migrate / get cpu id and check
+ */
 u64 read_time(void)
 {
        u64 walltime;
        long update_count;
-       struct time_struct this_cpu_time = 
-               per_cpu(cpu_time, smp_processor_id());
+       struct time_struct this_cpu_time;
        struct time_info *current_time;
+       unsigned int cpu;
        do {
+               cpu = _smp_processor_id();
+               this_cpu_time = per_cpu(cpu_time, cpu);
                update_count = this_cpu_time->update_count;
                current_time = this_cpu_time->time_sel[update_count&1];
                walltime = current_time->walltime + 
                                (get_cycles() - current_time->tsc) /
                                current_time->freq;
-       } while(this_cpu_time->update_count != update_count);
+       } while(this_cpu_time->update_count != update_count
+               || cpu != _smp_processor_id());
        return walltime;
 }