@@ -224,13 +224,6 @@ memory usage. Its seven fields are explained in Table 1-3. The stat file
contains detailed information about the process itself. Its fields are
explained in Table 1-4.
-(for SMP CONFIG users)
-
-For making accounting scalable, RSS related information are handled in an
-asynchronous manner and the value may not be very precise. To see a precise
-snapshot of a moment, you can see /proc/<pid>/smaps file and scan page table.
-It's slow but very precise.
-
.. table:: Table 1-2: Contents of the status files (as of 4.19)
========================== ===================================================
@@ -988,8 +988,6 @@ static int exec_mmap(struct mm_struct *mm)
tsk = current;
old_mm = current->mm;
exec_mm_release(tsk, old_mm);
- if (old_mm)
- sync_mm_rss(old_mm);
ret = down_write_killable(&tsk->signal->exec_update_lock);
if (ret)
@@ -1998,17 +1998,7 @@ static inline bool get_user_page_fast_only(unsigned long addr,
*/
static inline unsigned long get_mm_counter(struct mm_struct *mm, int member)
{
- long val = atomic_long_read(&mm->rss_stat.count[member]);
-
-#ifdef SPLIT_RSS_COUNTING
- /*
- * counter is updated in asynchronous manner and may go to minus.
- * But it's never be expected number for users.
- */
- if (val < 0)
- val = 0;
-#endif
- return (unsigned long)val;
+ return atomic_long_read(&mm->rss_stat.count[member]);
}
void mm_trace_rss_stat(struct mm_struct *mm, int member, long count);
@@ -2094,14 +2084,6 @@ static inline void setmax_mm_hiwater_rss(unsigned long *maxrss,
*maxrss = hiwater_rss;
}
-#if defined(SPLIT_RSS_COUNTING)
-void sync_mm_rss(struct mm_struct *mm);
-#else
-static inline void sync_mm_rss(struct mm_struct *mm)
-{
-}
-#endif
-
#ifndef CONFIG_ARCH_HAS_PTE_SPECIAL
static inline int pte_special(pte_t pte)
{
@@ -48,15 +48,6 @@ enum {
NR_MM_COUNTERS
};
-#if USE_SPLIT_PTE_PTLOCKS && defined(CONFIG_MMU)
-#define SPLIT_RSS_COUNTING
-/* per-thread cached information, */
-struct task_rss_stat {
- int events; /* for synchronization threshold */
- int count[NR_MM_COUNTERS];
-};
-#endif /* USE_SPLIT_PTE_PTLOCKS */
-
struct mm_rss_stat {
atomic_long_t count[NR_MM_COUNTERS];
};
@@ -861,9 +861,6 @@ struct task_struct {
/* Per-thread vma caching: */
struct vmacache vmacache;
-#ifdef SPLIT_RSS_COUNTING
- struct task_rss_stat rss_stat;
-#endif
int exit_state;
int exit_code;
int exit_signal;
@@ -482,7 +482,6 @@ static void exit_mm(void)
exit_mm_release(current, mm);
if (!mm)
return;
- sync_mm_rss(mm);
mmap_read_lock(mm);
mmgrab(mm);
BUG_ON(mm != current->active_mm);
@@ -749,10 +748,6 @@ void __noreturn do_exit(long code)
io_uring_files_cancel();
exit_signals(tsk); /* sets PF_EXITING */
-
- /* sync mm's RSS info before statistics gathering */
- if (tsk->mm)
- sync_mm_rss(tsk->mm);
acct_update_integrals(tsk);
group_dead = atomic_dec_and_test(&tsk->signal->live);
if (group_dead) {
@@ -2145,10 +2145,6 @@ static __latent_entropy struct task_struct *copy_process(
p->io_uring = NULL;
#endif
-#if defined(SPLIT_RSS_COUNTING)
- memset(&p->rss_stat, 0, sizeof(p->rss_stat));
-#endif
-
p->default_timer_slack_ns = current->timer_slack_ns;
#ifdef CONFIG_PSI
@@ -1463,7 +1463,6 @@ void kthread_unuse_mm(struct mm_struct *mm)
* clearing tsk->mm.
*/
smp_mb__after_spinlock();
- sync_mm_rss(mm);
local_irq_disable();
tsk->mm = NULL;
membarrier_update_current_mm(NULL);
@@ -711,12 +711,9 @@ static int madvise_free_pte_range(pmd_t *pmd, unsigned long addr,
mark_page_lazyfree(page);
}
out:
- if (nr_swap) {
- if (current->mm == mm)
- sync_mm_rss(mm);
-
+ if (nr_swap)
add_mm_counter(mm, MM_SWAPENTS, nr_swap);
- }
+
arch_leave_lazy_mmu_mode();
pte_unmap_unlock(orig_pte, ptl);
cond_resched();
@@ -176,53 +176,9 @@ void mm_trace_rss_stat(struct mm_struct *mm, int member, long count)
trace_rss_stat(mm, member, count);
}
-#if defined(SPLIT_RSS_COUNTING)
-
-void sync_mm_rss(struct mm_struct *mm)
-{
- int i;
-
- for (i = 0; i < NR_MM_COUNTERS; i++) {
- if (current->rss_stat.count[i]) {
- add_mm_counter(mm, i, current->rss_stat.count[i]);
- current->rss_stat.count[i] = 0;
- }
- }
- current->rss_stat.events = 0;
-}
-
-static void add_mm_counter_fast(struct mm_struct *mm, int member, int val)
-{
- struct task_struct *task = current;
-
- if (likely(task->mm == mm))
- task->rss_stat.count[member] += val;
- else
- add_mm_counter(mm, member, val);
-}
-#define inc_mm_counter_fast(mm, member) add_mm_counter_fast(mm, member, 1)
-#define dec_mm_counter_fast(mm, member) add_mm_counter_fast(mm, member, -1)
-
-/* sync counter once per 64 page faults */
-#define TASK_RSS_EVENTS_THRESH (64)
-static void check_sync_rss_stat(struct task_struct *task)
-{
- if (unlikely(task != current))
- return;
- if (unlikely(task->rss_stat.events++ > TASK_RSS_EVENTS_THRESH))
- sync_mm_rss(task->mm);
-}
-#else /* SPLIT_RSS_COUNTING */
-
#define inc_mm_counter_fast(mm, member) inc_mm_counter(mm, member)
#define dec_mm_counter_fast(mm, member) dec_mm_counter(mm, member)
-static void check_sync_rss_stat(struct task_struct *task)
-{
-}
-
-#endif /* SPLIT_RSS_COUNTING */
-
/*
* Note: this doesn't free the actual pages themselves. That
* has been handled earlier when unmapping all the memory regions.
@@ -502,8 +458,6 @@ static inline void add_mm_rss_vec(struct mm_struct *mm, int *rss)
{
int i;
- if (current->mm == mm)
- sync_mm_rss(mm);
for (i = 0; i < NR_MM_COUNTERS; i++)
if (rss[i])
add_mm_counter(mm, i, rss[i]);
@@ -5120,9 +5074,6 @@ vm_fault_t handle_mm_fault(struct vm_area_struct *vma, unsigned long address,
count_vm_event(PGFAULT);
count_memcg_event_mm(vma->vm_mm, PGFAULT);
- /* do counter updates before entering really critical section. */
- check_sync_rss_stat(current);
-
if (!arch_vma_access_permitted(vma, flags & FAULT_FLAG_WRITE,
flags & FAULT_FLAG_INSTRUCTION,
flags & FAULT_FLAG_REMOTE))