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From 1bb6422feb2c5d6c151b91f71dac97b33685af69 Mon Sep 17 00:00:00 2001
From: Thomas Gleixner <tglx@linutronix.de>
Date: Tue, 12 Jul 2011 11:39:36 +0200
Subject: [PATCH 177/347] mm/vmalloc: Another preempt disable region which
sucks
Origin: https://www.kernel.org/pub/linux/kernel/projects/rt/4.19/older/patches-4.19.246-rt110.tar.xz
Avoid the preempt disable version of get_cpu_var(). The inner-lock should
provide enough serialisation.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
---
mm/vmalloc.c | 13 ++++++++-----
1 file changed, 8 insertions(+), 5 deletions(-)
diff --git a/mm/vmalloc.c b/mm/vmalloc.c
index 1817871b0239..aa06badc76f4 100644
--- a/mm/vmalloc.c
+++ b/mm/vmalloc.c
@@ -853,7 +853,7 @@ static void *new_vmap_block(unsigned int order, gfp_t gfp_mask)
struct vmap_block *vb;
struct vmap_area *va;
unsigned long vb_idx;
- int node, err;
+ int node, err, cpu;
void *vaddr;
node = numa_node_id();
@@ -896,11 +896,12 @@ static void *new_vmap_block(unsigned int order, gfp_t gfp_mask)
BUG_ON(err);
radix_tree_preload_end();
- vbq = &get_cpu_var(vmap_block_queue);
+ cpu = get_cpu_light();
+ vbq = this_cpu_ptr(&vmap_block_queue);
spin_lock(&vbq->lock);
list_add_tail_rcu(&vb->free_list, &vbq->free);
spin_unlock(&vbq->lock);
- put_cpu_var(vmap_block_queue);
+ put_cpu_light();
return vaddr;
}
@@ -969,6 +970,7 @@ static void *vb_alloc(unsigned long size, gfp_t gfp_mask)
struct vmap_block *vb;
void *vaddr = NULL;
unsigned int order;
+ int cpu;
BUG_ON(offset_in_page(size));
BUG_ON(size > PAGE_SIZE*VMAP_MAX_ALLOC);
@@ -983,7 +985,8 @@ static void *vb_alloc(unsigned long size, gfp_t gfp_mask)
order = get_order(size);
rcu_read_lock();
- vbq = &get_cpu_var(vmap_block_queue);
+ cpu = get_cpu_light();
+ vbq = this_cpu_ptr(&vmap_block_queue);
list_for_each_entry_rcu(vb, &vbq->free, free_list) {
unsigned long pages_off;
@@ -1006,7 +1009,7 @@ static void *vb_alloc(unsigned long size, gfp_t gfp_mask)
break;
}
- put_cpu_var(vmap_block_queue);
+ put_cpu_light();
rcu_read_unlock();
/* Allocate new block if nothing was found */
--
2.36.1
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