mm, oom: change type of oom_score_adj to short

The maximum oom_score_adj is 1000 and the minimum oom_score_adj is -1000,
so this range can be represented by the signed short type with no
functional change.  The extra space this frees up in struct signal_struct
will be used for per-thread oom kill flags in the next patch.

Signed-off-by: David Rientjes <rientjes@google.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Reviewed-by: Michal Hocko <mhocko@suse.cz>
Cc: Anton Vorontsov <anton.vorontsov@linaro.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
David Rientjes 2012-12-11 16:02:54 -08:00 committed by Linus Torvalds
parent fa26437517
commit a9c58b907d
9 changed files with 31 additions and 31 deletions

View File

@ -40,7 +40,7 @@
#include <linux/notifier.h> #include <linux/notifier.h>
static uint32_t lowmem_debug_level = 2; static uint32_t lowmem_debug_level = 2;
static int lowmem_adj[6] = { static short lowmem_adj[6] = {
0, 0,
1, 1,
6, 6,
@ -70,9 +70,9 @@ static int lowmem_shrink(struct shrinker *s, struct shrink_control *sc)
int rem = 0; int rem = 0;
int tasksize; int tasksize;
int i; int i;
int min_score_adj = OOM_SCORE_ADJ_MAX + 1; short min_score_adj = OOM_SCORE_ADJ_MAX + 1;
int selected_tasksize = 0; int selected_tasksize = 0;
int selected_oom_score_adj; short selected_oom_score_adj;
int array_size = ARRAY_SIZE(lowmem_adj); int array_size = ARRAY_SIZE(lowmem_adj);
int other_free = global_page_state(NR_FREE_PAGES); int other_free = global_page_state(NR_FREE_PAGES);
int other_file = global_page_state(NR_FILE_PAGES) - int other_file = global_page_state(NR_FILE_PAGES) -
@ -90,7 +90,7 @@ static int lowmem_shrink(struct shrinker *s, struct shrink_control *sc)
} }
} }
if (sc->nr_to_scan > 0) if (sc->nr_to_scan > 0)
lowmem_print(3, "lowmem_shrink %lu, %x, ofree %d %d, ma %d\n", lowmem_print(3, "lowmem_shrink %lu, %x, ofree %d %d, ma %hd\n",
sc->nr_to_scan, sc->gfp_mask, other_free, sc->nr_to_scan, sc->gfp_mask, other_free,
other_file, min_score_adj); other_file, min_score_adj);
rem = global_page_state(NR_ACTIVE_ANON) + rem = global_page_state(NR_ACTIVE_ANON) +
@ -107,7 +107,7 @@ static int lowmem_shrink(struct shrinker *s, struct shrink_control *sc)
rcu_read_lock(); rcu_read_lock();
for_each_process(tsk) { for_each_process(tsk) {
struct task_struct *p; struct task_struct *p;
int oom_score_adj; short oom_score_adj;
if (tsk->flags & PF_KTHREAD) if (tsk->flags & PF_KTHREAD)
continue; continue;
@ -141,11 +141,11 @@ static int lowmem_shrink(struct shrinker *s, struct shrink_control *sc)
selected = p; selected = p;
selected_tasksize = tasksize; selected_tasksize = tasksize;
selected_oom_score_adj = oom_score_adj; selected_oom_score_adj = oom_score_adj;
lowmem_print(2, "select %d (%s), adj %d, size %d, to kill\n", lowmem_print(2, "select %d (%s), adj %hd, size %d, to kill\n",
p->pid, p->comm, oom_score_adj, tasksize); p->pid, p->comm, oom_score_adj, tasksize);
} }
if (selected) { if (selected) {
lowmem_print(1, "send sigkill to %d (%s), adj %d, size %d\n", lowmem_print(1, "send sigkill to %d (%s), adj %hd, size %d\n",
selected->pid, selected->comm, selected->pid, selected->comm,
selected_oom_score_adj, selected_tasksize); selected_oom_score_adj, selected_tasksize);
lowmem_deathpending_timeout = jiffies + HZ; lowmem_deathpending_timeout = jiffies + HZ;
@ -176,7 +176,7 @@ static void __exit lowmem_exit(void)
} }
module_param_named(cost, lowmem_shrinker.seeks, int, S_IRUGO | S_IWUSR); module_param_named(cost, lowmem_shrinker.seeks, int, S_IRUGO | S_IWUSR);
module_param_array_named(adj, lowmem_adj, int, &lowmem_adj_size, module_param_array_named(adj, lowmem_adj, short, &lowmem_adj_size,
S_IRUGO | S_IWUSR); S_IRUGO | S_IWUSR);
module_param_array_named(minfree, lowmem_minfree, uint, &lowmem_minfree_size, module_param_array_named(minfree, lowmem_minfree, uint, &lowmem_minfree_size,
S_IRUGO | S_IWUSR); S_IRUGO | S_IWUSR);

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@ -985,7 +985,7 @@ static ssize_t oom_score_adj_read(struct file *file, char __user *buf,
{ {
struct task_struct *task = get_proc_task(file->f_path.dentry->d_inode); struct task_struct *task = get_proc_task(file->f_path.dentry->d_inode);
char buffer[PROC_NUMBUF]; char buffer[PROC_NUMBUF];
int oom_score_adj = OOM_SCORE_ADJ_MIN; short oom_score_adj = OOM_SCORE_ADJ_MIN;
unsigned long flags; unsigned long flags;
size_t len; size_t len;
@ -996,7 +996,7 @@ static ssize_t oom_score_adj_read(struct file *file, char __user *buf,
unlock_task_sighand(task, &flags); unlock_task_sighand(task, &flags);
} }
put_task_struct(task); put_task_struct(task);
len = snprintf(buffer, sizeof(buffer), "%d\n", oom_score_adj); len = snprintf(buffer, sizeof(buffer), "%hd\n", oom_score_adj);
return simple_read_from_buffer(buf, count, ppos, buffer, len); return simple_read_from_buffer(buf, count, ppos, buffer, len);
} }
@ -1043,15 +1043,15 @@ static ssize_t oom_score_adj_write(struct file *file, const char __user *buf,
goto err_task_lock; goto err_task_lock;
} }
if (oom_score_adj < task->signal->oom_score_adj_min && if ((short)oom_score_adj < task->signal->oom_score_adj_min &&
!capable(CAP_SYS_RESOURCE)) { !capable(CAP_SYS_RESOURCE)) {
err = -EACCES; err = -EACCES;
goto err_sighand; goto err_sighand;
} }
task->signal->oom_score_adj = oom_score_adj; task->signal->oom_score_adj = (short)oom_score_adj;
if (has_capability_noaudit(current, CAP_SYS_RESOURCE)) if (has_capability_noaudit(current, CAP_SYS_RESOURCE))
task->signal->oom_score_adj_min = oom_score_adj; task->signal->oom_score_adj_min = (short)oom_score_adj;
trace_oom_score_adj_update(task); trace_oom_score_adj_update(task);
err_sighand: err_sighand:

View File

@ -29,8 +29,8 @@ enum oom_scan_t {
OOM_SCAN_SELECT, /* always select this thread first */ OOM_SCAN_SELECT, /* always select this thread first */
}; };
extern void compare_swap_oom_score_adj(int old_val, int new_val); extern void compare_swap_oom_score_adj(short old_val, short new_val);
extern int test_set_oom_score_adj(int new_val); extern short test_set_oom_score_adj(short new_val);
extern unsigned long oom_badness(struct task_struct *p, extern unsigned long oom_badness(struct task_struct *p,
struct mem_cgroup *memcg, const nodemask_t *nodemask, struct mem_cgroup *memcg, const nodemask_t *nodemask,

View File

@ -631,9 +631,9 @@ struct signal_struct {
struct rw_semaphore group_rwsem; struct rw_semaphore group_rwsem;
#endif #endif
int oom_score_adj; /* OOM kill score adjustment */ short oom_score_adj; /* OOM kill score adjustment */
int oom_score_adj_min; /* OOM kill score adjustment minimum value. short oom_score_adj_min; /* OOM kill score adjustment min value.
* Only settable by CAP_SYS_RESOURCE. */ * Only settable by CAP_SYS_RESOURCE. */
struct mutex cred_guard_mutex; /* guard against foreign influences on struct mutex cred_guard_mutex; /* guard against foreign influences on
* credential calculations * credential calculations

View File

@ -14,7 +14,7 @@ TRACE_EVENT(oom_score_adj_update,
TP_STRUCT__entry( TP_STRUCT__entry(
__field( pid_t, pid) __field( pid_t, pid)
__array( char, comm, TASK_COMM_LEN ) __array( char, comm, TASK_COMM_LEN )
__field( int, oom_score_adj) __field( short, oom_score_adj)
), ),
TP_fast_assign( TP_fast_assign(
@ -23,7 +23,7 @@ TRACE_EVENT(oom_score_adj_update,
__entry->oom_score_adj = task->signal->oom_score_adj; __entry->oom_score_adj = task->signal->oom_score_adj;
), ),
TP_printk("pid=%d comm=%s oom_score_adj=%d", TP_printk("pid=%d comm=%s oom_score_adj=%hd",
__entry->pid, __entry->comm, __entry->oom_score_adj) __entry->pid, __entry->comm, __entry->oom_score_adj)
); );

View File

@ -15,7 +15,7 @@ TRACE_EVENT(task_newtask,
__field( pid_t, pid) __field( pid_t, pid)
__array( char, comm, TASK_COMM_LEN) __array( char, comm, TASK_COMM_LEN)
__field( unsigned long, clone_flags) __field( unsigned long, clone_flags)
__field( int, oom_score_adj) __field( short, oom_score_adj)
), ),
TP_fast_assign( TP_fast_assign(
@ -25,7 +25,7 @@ TRACE_EVENT(task_newtask,
__entry->oom_score_adj = task->signal->oom_score_adj; __entry->oom_score_adj = task->signal->oom_score_adj;
), ),
TP_printk("pid=%d comm=%s clone_flags=%lx oom_score_adj=%d", TP_printk("pid=%d comm=%s clone_flags=%lx oom_score_adj=%hd",
__entry->pid, __entry->comm, __entry->pid, __entry->comm,
__entry->clone_flags, __entry->oom_score_adj) __entry->clone_flags, __entry->oom_score_adj)
); );
@ -40,7 +40,7 @@ TRACE_EVENT(task_rename,
__field( pid_t, pid) __field( pid_t, pid)
__array( char, oldcomm, TASK_COMM_LEN) __array( char, oldcomm, TASK_COMM_LEN)
__array( char, newcomm, TASK_COMM_LEN) __array( char, newcomm, TASK_COMM_LEN)
__field( int, oom_score_adj) __field( short, oom_score_adj)
), ),
TP_fast_assign( TP_fast_assign(
@ -50,7 +50,7 @@ TRACE_EVENT(task_rename,
__entry->oom_score_adj = task->signal->oom_score_adj; __entry->oom_score_adj = task->signal->oom_score_adj;
), ),
TP_printk("pid=%d oldcomm=%s newcomm=%s oom_score_adj=%d", TP_printk("pid=%d oldcomm=%s newcomm=%s oom_score_adj=%hd",
__entry->pid, __entry->oldcomm, __entry->pid, __entry->oldcomm,
__entry->newcomm, __entry->oom_score_adj) __entry->newcomm, __entry->oom_score_adj)
); );

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@ -1919,7 +1919,7 @@ static ssize_t run_store(struct kobject *kobj, struct kobj_attribute *attr,
if (ksm_run != flags) { if (ksm_run != flags) {
ksm_run = flags; ksm_run = flags;
if (flags & KSM_RUN_UNMERGE) { if (flags & KSM_RUN_UNMERGE) {
int oom_score_adj; short oom_score_adj;
oom_score_adj = test_set_oom_score_adj(OOM_SCORE_ADJ_MAX); oom_score_adj = test_set_oom_score_adj(OOM_SCORE_ADJ_MAX);
err = unmerge_and_remove_all_rmap_items(); err = unmerge_and_remove_all_rmap_items();

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@ -53,7 +53,7 @@ static DEFINE_SPINLOCK(zone_scan_lock);
* @old_val. Usually used to reinstate a previous value to prevent racing with * @old_val. Usually used to reinstate a previous value to prevent racing with
* userspacing tuning the value in the interim. * userspacing tuning the value in the interim.
*/ */
void compare_swap_oom_score_adj(int old_val, int new_val) void compare_swap_oom_score_adj(short old_val, short new_val)
{ {
struct sighand_struct *sighand = current->sighand; struct sighand_struct *sighand = current->sighand;
@ -72,7 +72,7 @@ void compare_swap_oom_score_adj(int old_val, int new_val)
* synchronization and returns the old value. Usually used to temporarily * synchronization and returns the old value. Usually used to temporarily
* set a value, save the old value in the caller, and then reinstate it later. * set a value, save the old value in the caller, and then reinstate it later.
*/ */
int test_set_oom_score_adj(int new_val) short test_set_oom_score_adj(short new_val)
{ {
struct sighand_struct *sighand = current->sighand; struct sighand_struct *sighand = current->sighand;
int old_val; int old_val;
@ -193,7 +193,7 @@ unsigned long oom_badness(struct task_struct *p, struct mem_cgroup *memcg,
if (!p) if (!p)
return 0; return 0;
adj = p->signal->oom_score_adj; adj = (long)p->signal->oom_score_adj;
if (adj == OOM_SCORE_ADJ_MIN) { if (adj == OOM_SCORE_ADJ_MIN) {
task_unlock(p); task_unlock(p);
return 0; return 0;
@ -399,7 +399,7 @@ static void dump_tasks(const struct mem_cgroup *memcg, const nodemask_t *nodemas
continue; continue;
} }
pr_info("[%5d] %5d %5d %8lu %8lu %7lu %8lu %5d %s\n", pr_info("[%5d] %5d %5d %8lu %8lu %7lu %8lu %5hd %s\n",
task->pid, from_kuid(&init_user_ns, task_uid(task)), task->pid, from_kuid(&init_user_ns, task_uid(task)),
task->tgid, task->mm->total_vm, get_mm_rss(task->mm), task->tgid, task->mm->total_vm, get_mm_rss(task->mm),
task->mm->nr_ptes, task->mm->nr_ptes,
@ -415,7 +415,7 @@ static void dump_header(struct task_struct *p, gfp_t gfp_mask, int order,
{ {
task_lock(current); task_lock(current);
pr_warning("%s invoked oom-killer: gfp_mask=0x%x, order=%d, " pr_warning("%s invoked oom-killer: gfp_mask=0x%x, order=%d, "
"oom_score_adj=%d\n", "oom_score_adj=%hd\n",
current->comm, gfp_mask, order, current->comm, gfp_mask, order,
current->signal->oom_score_adj); current->signal->oom_score_adj);
cpuset_print_task_mems_allowed(current); cpuset_print_task_mems_allowed(current);

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@ -1498,7 +1498,7 @@ SYSCALL_DEFINE1(swapoff, const char __user *, specialfile)
struct address_space *mapping; struct address_space *mapping;
struct inode *inode; struct inode *inode;
struct filename *pathname; struct filename *pathname;
int oom_score_adj; short oom_score_adj;
int i, type, prev; int i, type, prev;
int err; int err;