The patch titled
Subject: z3fold: remove preempt disabled sections for RT
has been added to the -mm tree. Its filename is
z3fold-remove-preempt-disabled-sections-for-rt.patch
This patch should soon appear at
https://ozlabs.org/~akpm/mmots/broken-out/z3fold-remove-preempt-disabled-sections-for-rt.patch
and later at
https://ozlabs.org/~akpm/mmotm/broken-out/z3fold-remove-preempt-disabled-sections-for-rt.patch
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*** Remember to use Documentation/process/submit-checklist.rst when testing your code ***
The -mm tree is included into linux-next and is updated
there every 3-4 working days
------------------------------------------------------
From: Vitaly Wool <vitaly.wool@xxxxxxxxxxxx>
Subject: z3fold: remove preempt disabled sections for RT
Replace get_cpu_ptr() with migrate_disable()+this_cpu_ptr() so RT can take
spinlocks that become sleeping locks.
Signed-off-by Mike Galbraith <efault@xxxxxx>
Link: https://lkml.kernel.org/r/20201209145151.18994-3-vitaly.wool@xxxxxxxxxxxx
Signed-off-by: Vitaly Wool <vitaly.wool@xxxxxxxxxxxx>
Cc: Sebastian Andrzej Siewior <bigeasy@xxxxxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
mm/z3fold.c | 17 ++++++++++-------
1 file changed, 10 insertions(+), 7 deletions(-)
--- a/mm/z3fold.c~z3fold-remove-preempt-disabled-sections-for-rt
+++ a/mm/z3fold.c
@@ -623,14 +623,16 @@ static inline void add_to_unbuddied(stru
{
if (zhdr->first_chunks == 0 || zhdr->last_chunks == 0 ||
zhdr->middle_chunks == 0) {
- struct list_head *unbuddied = get_cpu_ptr(pool->unbuddied);
-
+ struct list_head *unbuddied;
int freechunks = num_free_chunks(zhdr);
+
+ migrate_disable();
+ unbuddied = this_cpu_ptr(pool->unbuddied);
spin_lock(&pool->lock);
list_add(&zhdr->buddy, &unbuddied[freechunks]);
spin_unlock(&pool->lock);
zhdr->cpu = smp_processor_id();
- put_cpu_ptr(pool->unbuddied);
+ migrate_enable();
}
}
@@ -880,8 +882,9 @@ static inline struct z3fold_header *__z3
int chunks = size_to_chunks(size), i;
lookup:
+ migrate_disable();
/* First, try to find an unbuddied z3fold page. */
- unbuddied = get_cpu_ptr(pool->unbuddied);
+ unbuddied = this_cpu_ptr(pool->unbuddied);
for_each_unbuddied_list(i, chunks) {
struct list_head *l = &unbuddied[i];
@@ -899,7 +902,7 @@ lookup:
!z3fold_page_trylock(zhdr)) {
spin_unlock(&pool->lock);
zhdr = NULL;
- put_cpu_ptr(pool->unbuddied);
+ migrate_enable();
if (can_sleep)
cond_resched();
goto lookup;
@@ -913,7 +916,7 @@ lookup:
test_bit(PAGE_CLAIMED, &page->private)) {
z3fold_page_unlock(zhdr);
zhdr = NULL;
- put_cpu_ptr(pool->unbuddied);
+ migrate_enable();
if (can_sleep)
cond_resched();
goto lookup;
@@ -928,7 +931,7 @@ lookup:
kref_get(&zhdr->refcount);
break;
}
- put_cpu_ptr(pool->unbuddied);
+ migrate_enable();
if (!zhdr) {
int cpu;
_
Patches currently in -mm which might be from vitaly.wool@xxxxxxxxxxxx are
z3fold-simplify-freeing-slots.patch
z3fold-stricter-locking-and-more-careful-reclaim.patch
z3fold-remove-preempt-disabled-sections-for-rt.patch
