Palacios Public Git Repository

To checkout Palacios execute

  git clone http://v3vee.org/palacios/palacios.web/palacios.git
This will give you the master branch. You probably want the devel branch or one of the release branches. To switch to the devel branch, simply execute
  cd palacios
  git checkout --track -b devel origin/devel
The other branches are similar.


Halt handling uses global performance parameters to decide yield strategy
Peter Dinda [Thu, 9 Aug 2012 18:48:49 +0000 (13:48 -0500)]
palacios/src/palacios/vmm_halt.c

index 604d06b..b6e1a96 100644 (file)
@@ -21,6 +21,7 @@
 #include <palacios/vmm_halt.h>
 #include <palacios/vmm_intr.h>
 #include <palacios/vmm_lowlevel.h> 
+#include <palacios/vmm_perftune.h>
 
 #ifndef V3_CONFIG_DEBUG_HALT
 #undef PrintDebug
 #endif
 
 
-#define NO_PROGRESS_CYCLE_LIMIT  4000000ULL   // 4 million cycles, about 1ms on a 4 GHz machine
-
-#define YIELD_TIME_USEC    1000
-
-
 //
 // This should trigger a #GP if cpl != 0, otherwise, yield to host
 //
@@ -43,33 +39,22 @@ int v3_handle_halt(struct guest_info * info)
     if (info->cpl != 0) { 
        v3_raise_exception(info, GPF_EXCEPTION);
     } else {
-       uint64_t total_cycles;
+       uint64_t start_cycles;
        
-
        PrintDebug("CPU Yield\n");
 
-       total_cycles = 0;
+       start_cycles  = v3_get_host_time(&info->time_state);
 
        while (!v3_intr_pending(info) && (info->vm_info->run_state == VM_RUNNING)) {
             uint64_t t, cycles;
-           /* Yield, allowing time to pass while yielded */
+
            t = v3_get_host_time(&info->time_state);
 
-           // adaptively select the best yield option
-           if (total_cycles > NO_PROGRESS_CYCLE_LIMIT) { 
-               // Slow yield - will take at least YIELD_TIME_USEC to come back
-               v3_yield(info,YIELD_TIME_USEC);
-           } else {
-               // Fast yield - may come back immediately
-               v3_yield(info,-1);
-           }
+           /* Yield, allowing time to pass while yielded */
+           v3_strategy_driven_yield(info, v3_cycle_diff_in_usec(info, start_cycles, t));
 
            cycles = v3_get_host_time(&info->time_state) - t;
 
-           if ((total_cycles + cycles) > total_cycles) { 
-               total_cycles += cycles;
-           }
-
            v3_advance_time(info, &cycles);
 
            v3_update_timers(info);