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Ignore whitespace Rev 4663 → Rev 4679

/branches/sparc/kernel/arch/sparc64/src/smp/sun4v/smp.c
51,6 → 51,7
#include <arch/sun4v/md.h>
#include <arch/sun4v/ipi.h>
#include <time/delay.h>
#include <arch/smp/sun4v/smp.h>
 
/** hypervisor code of the "running" state of the CPU */
#define CPU_STATE_RUNNING 2
138,7 → 139,55
}
#endif
 
 
/**
* Proposes the optimal number of ready threads for each virtual processor
* in the given processor core so that the processor core is as busy as the
* average processor core. The proposed number of ready threads will be
* stored to the proposed_nrdy variable of the cpu_arch_t struture.
*/
bool calculate_optimal_nrdy(exec_unit_t *exec_unit) {
 
/* calculate the number of threads the core will steal */
int avg = atomic_get(&nrdy) / exec_unit_count;
int to_steal = avg - atomic_get(&(exec_units->nrdy));
if (to_steal < 0) {
return true;
} else if (to_steal == 0) {
return false;
}
 
/* initialize the proposals with the real numbers of ready threads */
unsigned int k;
for (k = 0; k < exec_unit->strand_count; k++) {
exec_units->cpus[k]->arch.proposed_nrdy =
atomic_get(&(exec_unit->cpus[k]->nrdy));
}
 
/* distribute the threads to be stolen to the core's CPUs */
int j;
for (j = to_steal; j > 0; j--) {
unsigned int k;
unsigned int least_busy = 0;
unsigned int least_busy_nrdy =
exec_unit->cpus[0]->arch.proposed_nrdy;
 
/* for each stolen thread, give it to the least busy CPU */
for (k = 0; k < exec_unit->strand_count; k++) {
if (exec_unit->cpus[k]->arch.proposed_nrdy
< least_busy_nrdy) {
least_busy = k;
least_busy_nrdy =
exec_unit->cpus[k]->arch.proposed_nrdy;
}
}
exec_unit->cpus[least_busy]->arch.proposed_nrdy++;
}
 
return false;
}
 
/**
* Finds out which execution units belong to particular CPUs. By execution unit
* we mean the physical core the logical processor is backed by. Since each
* Niagara physical core has just one integer execution unit and we will
238,6 → 287,8
if (i == exec_unit_count) {
exec_units[i].exec_unit_id = exec_unit_id;
exec_units[i].strand_count = 0;
atomic_set(&(exec_units[i].nrdy), 0);
spinlock_initialize(&(exec_units[i].proposed_nrdy_lock), "proposed nrdy lock");
exec_unit_count++;
}
 
275,6 → 326,8
exec_unit_count = 1;
exec_units[0].strand_count = cpu_count;
exec_units[0].exec_unit_id = 1;
spinlock_initialize(&(exec_units[0].proposed_nrdy_lock), "proposed nrdy lock");
atomic_set(&(exec_units[0].nrdy), 0);
max_core_strands = cpu_count;
 
/* browse CPUs again, assign them the fictional exec. unit */
344,7 → 397,11
if (cur_core_strand > exec_units[cur_core].strand_count)
continue;
 
cpus[cur_cpu++].arch.id = exec_units[cur_core].cpuids[cur_core_strand];
cpus[cur_cpu].arch.exec_unit = &(exec_units[cur_core]);
atomic_add(&(exec_units[cur_core].nrdy), atomic_get(&(cpus[cur_cpu].nrdy)));
cpus[cur_cpu].arch.id = exec_units[cur_core].cpuids[cur_core_strand];
exec_units[cur_core].cpus[cur_core_strand] = &(cpus[cur_cpu]);
cur_cpu++;
}
}
}