float_utilst::unbiased_floatt float_utilst::unpack(const bvt &src)
{
assert(src.size()==spec.width());
unbiased_floatt result;
result.sign=sign_bit(src);
result.fraction=get_fraction(src);
result.fraction.push_back(is_normal(src)); // add hidden bit
result.exponent=get_exponent(src);
assert(result.exponent.size()==spec.e);
// unbias the exponent
literalt denormal=bv_utils.is_zero(result.exponent);
result.exponent=
bv_utils.select(denormal,
bv_utils.build_constant(-spec.bias()+1, spec.e),
sub_bias(result.exponent));
result.infinity=is_infinity(src);
result.zero=is_zero(src);
result.NaN=is_NaN(src);
return result;
}
mp_integer ieee_floatt::pack() const
{
mp_integer result=0;
// sign bit
if(sign_flag)
result+=power(2, spec.e+spec.f);
if(NaN_flag)
{
result+=power(2, spec.f)*spec.max_exponent();
result+=1;
}
else if(infinity_flag)
{
result+=power(2, spec.f)*spec.max_exponent();
}
else if(fraction==0 && exponent==0)
{
// zero
}
else if(is_normal()) // normal?
{
// fraction -- need to hide hidden bit
result+=fraction-power(2, spec.f); // hidden bit
// exponent -- bias!
result+=power(2, spec.f)*(exponent+spec.bias());
}
else // denormal
{
result+=fraction; // denormal -- no hidden bit
// the exponent is zero
}
return result;
}
static int lowmem_shrink(struct shrinker *s, struct shrink_control *sc)
{
struct task_struct *tsk;
struct task_struct *selected = NULL;
int rem = 0;
int tasksize;
int i;
int min_score_adj = OOM_SCORE_ADJ_MAX + 1;
int selected_tasksize = 0;
int selected_oom_score_adj;
int selected_oom_adj = 0;
int array_size = ARRAY_SIZE(lowmem_adj);
int other_free;
int other_file;
int reserved_free = 0;
int cma_free = 0;
unsigned long nr_to_scan = sc->nr_to_scan;
struct zone *zone;
int use_cma = can_use_cma_pages(sc->gfp_mask);
if (nr_to_scan > 0) {
if (!mutex_trylock(&scan_mutex)) {
if (!(lowmem_only_kswapd_sleep && !current_is_kswapd())) {
msleep_interruptible(lowmem_sleep_ms);
}
return 0;
}
}
for_each_zone(zone)
{
if (is_normal(zone))
reserved_free = zone->watermark[WMARK_MIN] + zone->lowmem_reserve[_ZONE];
cma_free += zone_page_state(zone, NR_FREE_CMA_PAGES);
}
other_free = global_page_state(NR_FREE_PAGES);
if (global_page_state(NR_SHMEM) + global_page_state(NR_MLOCK) + total_swapcache_pages <
global_page_state(NR_FILE_PAGES))
other_file = global_page_state(NR_FILE_PAGES) -
global_page_state(NR_SHMEM) -
global_page_state(NR_MLOCK) -
total_swapcache_pages;
else
other_file = 0;
if (lowmem_adj_size < array_size)
array_size = lowmem_adj_size;
if (lowmem_minfree_size < array_size)
array_size = lowmem_minfree_size;
for (i = 0; i < array_size; i++) {
if ((other_free - reserved_free - (use_cma ? 0 : cma_free)) < lowmem_minfree[i] &&
other_file < lowmem_minfree[i]) {
min_score_adj = lowmem_adj[i];
break;
}
}
if (nr_to_scan > 0)
lowmem_print(3, "lowmem_shrink %lu, %x, ofree %d %d, ma %d, rfree %d\n",
nr_to_scan, sc->gfp_mask, other_free,
other_file, min_score_adj, reserved_free);
rem = global_page_state(NR_ACTIVE_ANON) +
global_page_state(NR_ACTIVE_FILE) +
global_page_state(NR_INACTIVE_ANON) +
global_page_state(NR_INACTIVE_FILE);
if (nr_to_scan <= 0 || min_score_adj == OOM_SCORE_ADJ_MAX + 1) {
lowmem_print(5, "lowmem_shrink %lu, %x, return %d\n",
nr_to_scan, sc->gfp_mask, rem);
if (nr_to_scan > 0)
mutex_unlock(&scan_mutex);
return rem;
}
selected_oom_score_adj = min_score_adj;
rcu_read_lock();
for_each_process(tsk) {
struct task_struct *p;
int oom_score_adj;
if (tsk->flags & PF_KTHREAD)
continue;
if (test_task_flag(tsk, TIF_MM_RELEASED))
continue;
if (time_before_eq(jiffies, lowmem_deathpending_timeout)) {
if (test_task_flag(tsk, TIF_MEMDIE)) {
lowmem_print(2, "skipping , waiting for process %d (%s) dead\n",
tsk->pid, tsk->comm);
rcu_read_unlock();
if (!(lowmem_only_kswapd_sleep && !current_is_kswapd())) {
msleep_interruptible(lowmem_sleep_ms);
}
mutex_unlock(&scan_mutex);
return 0;
}
}
p = find_lock_task_mm(tsk);
if (!p)
continue;
oom_score_adj = p->signal->oom_score_adj;
if (oom_score_adj < min_score_adj) {
task_unlock(p);
continue;
}
tasksize = get_mm_rss(p->mm);
task_unlock(p);
if (tasksize <= 0)
continue;
if (selected) {
if (oom_score_adj < selected_oom_score_adj)
continue;
if (oom_score_adj == selected_oom_score_adj &&
tasksize <= selected_tasksize)
continue;
}
selected = p;
selected_tasksize = tasksize;
selected_oom_score_adj = oom_score_adj;
selected_oom_adj = p->signal->oom_adj;
lowmem_print(2, "select %d (%s), oom_adj %d score_adj %d, size %d, to kill\n",
p->pid, p->comm, selected_oom_adj, oom_score_adj, tasksize);
}
if (selected) {
bool should_dump_meminfo = false;
lowmem_print(1, "[%s] send sigkill to %d (%s), oom_adj %d, score_adj %d,"
" min_score_adj %d, size %dK, free %dK, file %dK, "
" reserved_free %dK, cma_free %dK, use_cma %d\n",
current->comm, selected->pid, selected->comm,
selected_oom_adj, selected_oom_score_adj,
min_score_adj, selected_tasksize << 2,
other_free << 2, other_file << 2, reserved_free << 2, cma_free << 2, use_cma);
if (!current_is_kswapd() && current->reclaim_state)
current->reclaim_state->trigger_lmk++;
lowmem_deathpending_timeout = jiffies + HZ;
#ifdef CONFIG_ANDROID_LOW_MEMORY_KILLER_AUTODETECT_OOM_ADJ_VALUES
#define DUMP_INFO_OOM_SCORE_ADJ_THRESHOLD ((7 * OOM_SCORE_ADJ_MAX) / -OOM_DISABLE)
if (selected_oom_score_adj < DUMP_INFO_OOM_SCORE_ADJ_THRESHOLD)
#else
if (selected->signal->oom_adj < 7)
#endif
should_dump_meminfo = true;
send_sig(SIGKILL, selected, 0);
set_tsk_thread_flag(selected, TIF_MEMDIE);
rem -= selected_tasksize;
rcu_read_unlock();
if (should_dump_meminfo) {
show_meminfo();
dump_tasks();
}
if (!(lowmem_only_kswapd_sleep && !current_is_kswapd()))
msleep_interruptible(lowmem_sleep_ms);
} else
rcu_read_unlock();
lowmem_print(4, "lowmem_shrink %lu, %x, return %d\n",
nr_to_scan, sc->gfp_mask, rem);
mutex_unlock(&scan_mutex);
return rem;
}
static int lowmem_shrink(struct shrinker *s, struct shrink_control *sc)
{
struct task_struct *tsk;
struct task_struct *selected = NULL;
int rem = 0;
int tasksize;
int i;
int min_score_adj = OOM_SCORE_ADJ_MAX + 1;
int selected_tasksize = 0;
int selected_oom_score_adj;
int selected_oom_adj = 0;
int array_size = ARRAY_SIZE(lowmem_adj);
int other_free;
int other_file;
int reserved_free = 0;
unsigned long nr_to_scan = sc->nr_to_scan;
int fork_boost = 0;
size_t *min_array;
struct zone *zone;
if (nr_to_scan > 0) {
if (!mutex_trylock(&scan_mutex)) {
if (!(lowmem_only_kswapd_sleep && !current_is_kswapd())) {
msleep_interruptible(lowmem_sleep_ms);
}
return 0;
}
}
for_each_zone(zone)
{
if(is_normal(zone))
{
reserved_free = zone->watermark[WMARK_MIN] + zone->lowmem_reserve[_ZONE];
break;
}
}
other_free = global_page_state(NR_FREE_PAGES);
other_file = global_page_state(NR_FILE_PAGES) -
global_page_state(NR_SHMEM) - global_page_state(NR_MLOCK) ;
if (lowmem_fork_boost &&
time_before_eq(jiffies, lowmem_fork_boost_timeout)) {
for (i = 0; i < lowmem_minfree_size; i++)
minfree_tmp[i] = lowmem_minfree[i] + lowmem_fork_boost_minfree[i];
min_array = minfree_tmp;
}
else
min_array = lowmem_minfree;
if (lowmem_adj_size < array_size)
array_size = lowmem_adj_size;
if (lowmem_minfree_size < array_size)
array_size = lowmem_minfree_size;
for (i = 0; i < array_size; i++) {
if ((other_free - reserved_free) < min_array[i] &&
other_file < min_array[i]) {
min_score_adj = lowmem_adj[i];
fork_boost = lowmem_fork_boost_minfree[i];
break;
}
}
if (nr_to_scan > 0)
lowmem_print(3, "lowmem_shrink %lu, %x, ofree %d %d, ma %d, rfree %d\n",
nr_to_scan, sc->gfp_mask, other_free,
other_file, min_score_adj, reserved_free);
rem = global_page_state(NR_ACTIVE_ANON) +
global_page_state(NR_ACTIVE_FILE) +
global_page_state(NR_INACTIVE_ANON) +
global_page_state(NR_INACTIVE_FILE);
if (nr_to_scan <= 0 || min_score_adj == OOM_SCORE_ADJ_MAX + 1) {
lowmem_print(5, "lowmem_shrink %lu, %x, return %d\n",
nr_to_scan, sc->gfp_mask, rem);
if (nr_to_scan > 0)
mutex_unlock(&scan_mutex);
return rem;
}
selected_oom_score_adj = min_score_adj;
rcu_read_lock();
for_each_process(tsk) {
struct task_struct *p;
int oom_score_adj;
if (tsk->flags & PF_KTHREAD)
continue;
if (time_before_eq(jiffies, lowmem_deathpending_timeout)) {
if (test_task_flag(tsk, TIF_MEMDIE)) {
lowmem_print(2, "skipping , waiting for process %d (%s) dead\n",
tsk->pid, tsk->comm);
rcu_read_unlock();
if (!(lowmem_only_kswapd_sleep && !current_is_kswapd())) {
msleep_interruptible(lowmem_sleep_ms);
}
mutex_unlock(&scan_mutex);
return 0;
}
}
p = find_lock_task_mm(tsk);
if (!p)
continue;
oom_score_adj = p->signal->oom_score_adj;
if (oom_score_adj < selected_oom_score_adj) {
task_unlock(p);
continue;
}
tasksize = get_mm_rss(p->mm);
task_unlock(p);
if (tasksize <= 0)
continue;
if (selected && oom_score_adj == selected_oom_score_adj &&
tasksize <= selected_tasksize)
continue;
selected = p;
selected_tasksize = tasksize;
selected_oom_score_adj = oom_score_adj;
selected_oom_adj = p->signal->oom_adj;
lowmem_print(2, "select %d (%s), oom_adj %d score_adj %d, size %d, to kill\n",
p->pid, p->comm, selected_oom_adj, oom_score_adj, tasksize);
}
if (selected) {
lowmem_print(1, "[%s] send sigkill to %d (%s), oom_adj %d, score_adj %d,"
" min_score_adj %d, size %dK, free %dK, file %dK, fork_boost %dK,"
" reserved_free %dK\n",
current->comm, selected->pid, selected->comm,
selected_oom_adj, selected_oom_score_adj,
min_score_adj, selected_tasksize << 2,
other_free << 2, other_file << 2, fork_boost << 2, reserved_free << 2);
lowmem_deathpending_timeout = jiffies + HZ;
if (selected_oom_adj < 7)
{
show_meminfo();
dump_tasks();
}
send_sig(SIGKILL, selected, 0);
set_tsk_thread_flag(selected, TIF_MEMDIE);
rem -= selected_tasksize;
rcu_read_unlock();
if (!(lowmem_only_kswapd_sleep && !current_is_kswapd())) {
msleep_interruptible(lowmem_sleep_ms);
}
}
else
rcu_read_unlock();
lowmem_print(4, "lowmem_shrink %lu, %x, return %d\n",
sc->nr_to_scan, sc->gfp_mask, rem);
mutex_unlock(&scan_mutex);
return rem;
}
