void switch_mmu_context(struct mm_struct *prev, struct mm_struct *next)
{
unsigned int id, cpu = smp_processor_id();
unsigned long *map;
/* No lockless fast path .. yet */
atomic_spin_lock(&context_lock);
#ifndef DEBUG_STEAL_ONLY
pr_devel("[%d] activating context for mm @%p, active=%d, id=%d\n",
cpu, next, next->context.active, next->context.id);
#endif
#ifdef CONFIG_SMP
/* Mark us active and the previous one not anymore */
next->context.active++;
if (prev) {
#ifndef DEBUG_STEAL_ONLY
pr_devel(" old context %p active was: %d\n",
prev, prev->context.active);
#endif
WARN_ON(prev->context.active < 1);
prev->context.active--;
}
again:
#endif /* CONFIG_SMP */
/* If we already have a valid assigned context, skip all that */
id = next->context.id;
if (likely(id != MMU_NO_CONTEXT))
goto ctxt_ok;
/* We really don't have a context, let's try to acquire one */
id = next_context;
if (id > last_context)
id = first_context;
map = context_map;
/* No more free contexts, let's try to steal one */
if (nr_free_contexts == 0) {
#ifdef CONFIG_SMP
if (num_online_cpus() > 1) {
id = steal_context_smp(id);
if (id == MMU_NO_CONTEXT)
goto again;
goto stolen;
}
#endif /* CONFIG_SMP */
id = steal_context_up(id);
goto stolen;
}
nr_free_contexts--;
/* We know there's at least one free context, try to find it */
while (__test_and_set_bit(id, map)) {
id = find_next_zero_bit(map, last_context+1, id);
if (id > last_context)
id = first_context;
}
stolen:
next_context = id + 1;
context_mm[id] = next;
next->context.id = id;
#ifndef DEBUG_STEAL_ONLY
pr_devel("[%d] picked up new id %d, nrf is now %d\n",
cpu, id, nr_free_contexts);
#endif
context_check_map();
ctxt_ok:
/* If that context got marked stale on this CPU, then flush the
* local TLB for it and unmark it before we use it
*/
if (test_bit(id, stale_map[cpu])) {
pr_devel("[%d] flushing stale context %d for mm @%p !\n",
cpu, id, next);
local_flush_tlb_mm(next);
/* XXX This clear should ultimately be part of local_flush_tlb_mm */
__clear_bit(id, stale_map[cpu]);
}
/* Flick the MMU and release lock */
set_context(id, next->pgd);
atomic_spin_unlock(&context_lock);
}
void switch_mmu_context(struct mm_struct *prev, struct mm_struct *next,
struct task_struct *tsk)
{
unsigned int i, id, cpu = smp_processor_id();
unsigned long *map;
/* No lockless fast path .. yet */
raw_spin_lock(&context_lock);
pr_hard("[%d] activating context for mm @%p, active=%d, id=%d",
cpu, next, next->context.active, next->context.id);
#ifdef CONFIG_SMP
/* Mark us active and the previous one not anymore */
next->context.active++;
if (prev) {
pr_hardcont(" (old=0x%p a=%d)", prev, prev->context.active);
WARN_ON(prev->context.active < 1);
prev->context.active--;
}
again:
#endif /* CONFIG_SMP */
/* If we already have a valid assigned context, skip all that */
id = next->context.id;
if (likely(id != MMU_NO_CONTEXT)) {
#ifdef DEBUG_MAP_CONSISTENCY
if (context_mm[id] != next)
pr_err("MMU: mm 0x%p has id %d but context_mm[%d] says 0x%p\n",
next, id, id, context_mm[id]);
#endif
goto ctxt_ok;
}
/* We really don't have a context, let's try to acquire one */
id = next_context;
if (id > last_context)
id = first_context;
map = context_map;
/* No more free contexts, let's try to steal one */
if (nr_free_contexts == 0) {
#ifdef CONFIG_SMP
if (num_online_cpus() > 1) {
id = steal_context_smp(id);
if (id == MMU_NO_CONTEXT)
goto again;
goto stolen;
}
#endif /* CONFIG_SMP */
if (no_selective_tlbil)
id = steal_all_contexts();
else
id = steal_context_up(id);
goto stolen;
}
nr_free_contexts--;
/* We know there's at least one free context, try to find it */
while (__test_and_set_bit(id, map)) {
id = find_next_zero_bit(map, last_context+1, id);
if (id > last_context)
id = first_context;
}
stolen:
next_context = id + 1;
context_mm[id] = next;
next->context.id = id;
pr_hardcont(" | new id=%d,nrf=%d", id, nr_free_contexts);
context_check_map();
ctxt_ok:
/* If that context got marked stale on this CPU, then flush the
* local TLB for it and unmark it before we use it
*/
if (test_bit(id, stale_map[cpu])) {
pr_hardcont(" | stale flush %d [%d..%d]",
id, cpu_first_thread_sibling(cpu),
cpu_last_thread_sibling(cpu));
local_flush_tlb_mm(next);
/* XXX This clear should ultimately be part of local_flush_tlb_mm */
for (i = cpu_first_thread_sibling(cpu);
i <= cpu_last_thread_sibling(cpu); i++) {
if (stale_map[i])
__clear_bit(id, stale_map[i]);
}
}
/* Flick the MMU and release lock */
pr_hardcont(" -> %d\n", id);
set_context(id, next->pgd);
raw_spin_unlock(&context_lock);
}
void switch_mmu_context(struct mm_struct *prev, struct mm_struct *next)
{
unsigned int i, id, cpu = smp_processor_id();
unsigned long *map;
raw_spin_lock(&context_lock);
pr_hard("[%d] activating context for mm @%p, active=%d, id=%d",
cpu, next, next->context.active, next->context.id);
#ifdef CONFIG_SMP
next->context.active++;
if (prev) {
pr_hardcont(" (old=0x%p a=%d)", prev, prev->context.active);
WARN_ON(prev->context.active < 1);
prev->context.active--;
}
again:
#endif
id = next->context.id;
if (likely(id != MMU_NO_CONTEXT)) {
#ifdef DEBUG_MAP_CONSISTENCY
if (context_mm[id] != next)
pr_err("MMU: mm 0x%p has id %d but context_mm[%d] says 0x%p\n",
next, id, id, context_mm[id]);
#endif
goto ctxt_ok;
}
id = next_context;
if (id > last_context)
id = first_context;
map = context_map;
if (nr_free_contexts == 0) {
#ifdef CONFIG_SMP
if (num_online_cpus() > 1) {
id = steal_context_smp(id);
if (id == MMU_NO_CONTEXT)
goto again;
goto stolen;
}
#endif
id = steal_context_up(id);
goto stolen;
}
nr_free_contexts--;
while (__test_and_set_bit(id, map)) {
id = find_next_zero_bit(map, last_context+1, id);
if (id > last_context)
id = first_context;
}
stolen:
next_context = id + 1;
context_mm[id] = next;
next->context.id = id;
pr_hardcont(" | new id=%d,nrf=%d", id, nr_free_contexts);
context_check_map();
ctxt_ok:
if (test_bit(id, stale_map[cpu])) {
pr_hardcont(" | stale flush %d [%d..%d]",
id, cpu_first_thread_sibling(cpu),
cpu_last_thread_sibling(cpu));
local_flush_tlb_mm(next);
for (i = cpu_first_thread_sibling(cpu);
i <= cpu_last_thread_sibling(cpu); i++) {
__clear_bit(id, stale_map[i]);
}
}
pr_hardcont(" -> %d\n", id);
set_context(id, next->pgd);
raw_spin_unlock(&context_lock);
}
