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From f5fbf1dccda26971b16bafd3f861ce1f5956d7d7 Mon Sep 17 00:00:00 2001
From: Vitaly Wool <vitaly.wool@konsulko.com>
Date: Mon, 14 Dec 2020 19:12:36 -0800
Subject: [PATCH 001/323] z3fold: remove preempt disabled sections for RT
Origin: https://www.kernel.org/pub/linux/kernel/projects/rt/5.10/older/patches-5.10.215-rt107.tar.xz
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@gmx.de>
Link: https://lkml.kernel.org/r/20201209145151.18994-3-vitaly.wool@konsulko.com
Signed-off-by: Vitaly Wool <vitaly.wool@konsulko.com>
Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
---
mm/z3fold.c | 17 ++++++++++-------
1 file changed, 10 insertions(+), 7 deletions(-)
diff --git a/mm/z3fold.c b/mm/z3fold.c
index 912ac9a64a155..f3d875fcaeb77 100644
--- a/mm/z3fold.c
+++ b/mm/z3fold.c
@@ -623,14 +623,16 @@ static inline void add_to_unbuddied(struct z3fold_pool *pool,
{
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 *__z3fold_alloc(struct z3fold_pool *pool,
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 @@ static inline struct z3fold_header *__z3fold_alloc(struct z3fold_pool *pool,
!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 @@ static inline struct z3fold_header *__z3fold_alloc(struct z3fold_pool *pool,
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 @@ static inline struct z3fold_header *__z3fold_alloc(struct z3fold_pool *pool,
kref_get(&zhdr->refcount);
break;
}
- put_cpu_ptr(pool->unbuddied);
+ migrate_enable();
if (!zhdr) {
int cpu;
--
2.44.0
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