lkml.org 
[lkml]   [2018]   [Feb]   [6]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
Subject[PATCH] memremap: fix softlockup reports at teardown
From
Date
The cond_resched() currently in the setup path needs to be duplicated in
the teardown path. Rather than require each instance of
for_each_device_pfn() to open code the same sequence, embed it in the
helper.

Link: https://github.com/intel/ixpdimm_sw/issues/11
Cc: "Jérôme Glisse" <jglisse@redhat.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: <stable@vger.kernel.org>
Fixes: 71389703839e ("mm, zone_device: Replace {get, put}_zone_device_page()...")
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
---
kernel/memremap.c | 15 ++++++++++-----
1 file changed, 10 insertions(+), 5 deletions(-)

diff --git a/kernel/memremap.c b/kernel/memremap.c
index 4849be5f9b3c..4dd4274cabe2 100644
--- a/kernel/memremap.c
+++ b/kernel/memremap.c
@@ -275,8 +275,15 @@ static unsigned long pfn_end(struct dev_pagemap *pgmap)
return (res->start + resource_size(res)) >> PAGE_SHIFT;
}

+static unsigned long pfn_next(unsigned long pfn)
+{
+ if (pfn % 1024 == 0)
+ cond_resched();
+ return pfn + 1;
+}
+
#define for_each_device_pfn(pfn, map) \
- for (pfn = pfn_first(map); pfn < pfn_end(map); pfn++)
+ for (pfn = pfn_first(map); pfn < pfn_end(map); pfn = pfn_next(pfn))

static void devm_memremap_pages_release(void *data)
{
@@ -337,10 +344,10 @@ void *devm_memremap_pages(struct device *dev, struct dev_pagemap *pgmap)
resource_size_t align_start, align_size, align_end;
struct vmem_altmap *altmap = pgmap->altmap_valid ?
&pgmap->altmap : NULL;
+ struct resource *res = &pgmap->res;
unsigned long pfn, pgoff, order;
pgprot_t pgprot = PAGE_KERNEL;
- int error, nid, is_ram, i = 0;
- struct resource *res = &pgmap->res;
+ int error, nid, is_ram;

align_start = res->start & ~(SECTION_SIZE - 1);
align_size = ALIGN(res->start + resource_size(res), SECTION_SIZE)
@@ -409,8 +416,6 @@ void *devm_memremap_pages(struct device *dev, struct dev_pagemap *pgmap)
list_del(&page->lru);
page->pgmap = pgmap;
percpu_ref_get(pgmap->ref);
- if (!(++i % 1024))
- cond_resched();
}

devm_add_action(dev, devm_memremap_pages_release, pgmap);
\
 
 \ /
  Last update: 2018-02-07 04:44    [W:0.031 / U:2.956 seconds]
©2003-2018 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site