Re: [PATCH 1/3] CMA: Fix the bug that CMA's page number is substructed twice
On Tue, Dec 30, 2014 at 12:48 PM, Joonsoo Kim wrote: > On Thu, Dec 25, 2014 at 05:43:26PM +0800, Hui Zhu wrote: >> In Joonsoo's CMA patch "CMA: always treat free cma pages as non-free on >> watermark checking" [1], it changes __zone_watermark_ok to substruct CMA >> pages number from free_pages if system use CMA: >> if (IS_ENABLED(CONFIG_CMA) && z->managed_cma_pages) >> free_pages -= zone_page_state(z, NR_FREE_CMA_PAGES); > > Hello, > > In fact, without that patch, watermark checking has a problem in current > kernel. > If there is reserved CMA region, watermark check for high order > allocation is done loosly. See following thread. > > https://lkml.org/lkml/2014/5/30/320 > > Your patch can fix this situation, so, how about submitting this patch > separately? > > Thanks. > Hi Joonsoo, Thanks for your remind. I will post a separate patch for current kernel. Thanks, Hui -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: [PATCH 1/3] CMA: Fix the bug that CMA's page number is substructed twice
On Tue, Dec 30, 2014 at 12:48 PM, Joonsoo Kim iamjoonsoo@lge.com wrote: On Thu, Dec 25, 2014 at 05:43:26PM +0800, Hui Zhu wrote: In Joonsoo's CMA patch CMA: always treat free cma pages as non-free on watermark checking [1], it changes __zone_watermark_ok to substruct CMA pages number from free_pages if system use CMA: if (IS_ENABLED(CONFIG_CMA) z-managed_cma_pages) free_pages -= zone_page_state(z, NR_FREE_CMA_PAGES); Hello, In fact, without that patch, watermark checking has a problem in current kernel. If there is reserved CMA region, watermark check for high order allocation is done loosly. See following thread. https://lkml.org/lkml/2014/5/30/320 Your patch can fix this situation, so, how about submitting this patch separately? Thanks. Hi Joonsoo, Thanks for your remind. I will post a separate patch for current kernel. Thanks, Hui -- To unsubscribe from this list: send the line unsubscribe linux-kernel in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: [PATCH 1/3] CMA: Fix the bug that CMA's page number is substructed twice
On Thu, Dec 25, 2014 at 05:43:26PM +0800, Hui Zhu wrote: > In Joonsoo's CMA patch "CMA: always treat free cma pages as non-free on > watermark checking" [1], it changes __zone_watermark_ok to substruct CMA > pages number from free_pages if system use CMA: > if (IS_ENABLED(CONFIG_CMA) && z->managed_cma_pages) > free_pages -= zone_page_state(z, NR_FREE_CMA_PAGES); Hello, In fact, without that patch, watermark checking has a problem in current kernel. If there is reserved CMA region, watermark check for high order allocation is done loosly. See following thread. https://lkml.org/lkml/2014/5/30/320 Your patch can fix this situation, so, how about submitting this patch separately? Thanks. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: [PATCH 1/3] CMA: Fix the bug that CMA's page number is substructed twice
On Thu, Dec 25, 2014 at 05:43:26PM +0800, Hui Zhu wrote: In Joonsoo's CMA patch CMA: always treat free cma pages as non-free on watermark checking [1], it changes __zone_watermark_ok to substruct CMA pages number from free_pages if system use CMA: if (IS_ENABLED(CONFIG_CMA) z-managed_cma_pages) free_pages -= zone_page_state(z, NR_FREE_CMA_PAGES); Hello, In fact, without that patch, watermark checking has a problem in current kernel. If there is reserved CMA region, watermark check for high order allocation is done loosly. See following thread. https://lkml.org/lkml/2014/5/30/320 Your patch can fix this situation, so, how about submitting this patch separately? Thanks. -- To unsubscribe from this list: send the line unsubscribe linux-kernel in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
[PATCH 1/3] CMA: Fix the bug that CMA's page number is substructed twice
In Joonsoo's CMA patch "CMA: always treat free cma pages as non-free on
watermark checking" [1], it changes __zone_watermark_ok to substruct CMA
pages number from free_pages if system use CMA:
if (IS_ENABLED(CONFIG_CMA) && z->managed_cma_pages)
free_pages -= zone_page_state(z, NR_FREE_CMA_PAGES);
But after this part of code
for (o = 0; o < order; o++) {
/* At the next order, this order's pages become unavailable */
free_pages -= z->free_area[o].nr_free << o;
CMA memory in each order is part of z->free_area[o].nr_free, then the CMA
page number of this order is substructed twice. This bug will make
__zone_watermark_ok return more false.
This patch add cma_free_area to struct free_area that just record the number
of CMA pages. And add it back in the order loop to handle the substruct
twice issue.
[1] https://lkml.org/lkml/2014/5/28/110
Signed-off-by: Hui Zhu
Signed-off-by: Weixing Liu
---
include/linux/mmzone.h | 3 +++
mm/page_alloc.c| 29 -
2 files changed, 31 insertions(+), 1 deletion(-)
diff --git a/include/linux/mmzone.h b/include/linux/mmzone.h
index ee1ce1f..7ccad93 100644
--- a/include/linux/mmzone.h
+++ b/include/linux/mmzone.h
@@ -92,6 +92,9 @@ static inline int get_pfnblock_migratetype(struct page *page,
unsigned long pfn)
struct free_area {
struct list_headfree_list[MIGRATE_TYPES];
unsigned long nr_free;
+#ifdef CONFIG_CMA
+ unsigned long cma_nr_free;
+#endif
};
struct pglist_data;
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 1b6c82c..a8d9f03 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -650,6 +650,8 @@ static inline void __free_one_page(struct page *page,
} else {
list_del(>lru);
zone->free_area[order].nr_free--;
+ if (is_migrate_cma(migratetype))
+ zone->free_area[order].cma_nr_free--;
rmv_page_order(buddy);
}
combined_idx = buddy_idx & page_idx;
@@ -683,6 +685,8 @@ static inline void __free_one_page(struct page *page,
list_add(>lru, >free_area[order].free_list[migratetype]);
out:
zone->free_area[order].nr_free++;
+ if (is_migrate_cma(migratetype))
+ zone->free_area[order].cma_nr_free++;
}
static inline int free_pages_check(struct page *page)
@@ -987,6 +991,8 @@ static inline void expand(struct zone *zone, struct page
*page,
}
list_add([size].lru, >free_list[migratetype]);
area->nr_free++;
+ if (is_migrate_cma(migratetype))
+ area->cma_nr_free++;
set_page_order([size], high);
}
}
@@ -1070,6 +1076,8 @@ struct page *__rmqueue_smallest(struct zone *zone,
unsigned int order,
list_del(>lru);
rmv_page_order(page);
area->nr_free--;
+ if (is_migrate_cma(migratetype))
+ area->cma_nr_free--;
expand(zone, page, order, current_order, area, migratetype);
set_freepage_migratetype(page, migratetype);
return page;
@@ -1258,6 +1266,8 @@ __rmqueue_fallback(struct zone *zone, unsigned int order,
int start_migratetype)
page = list_entry(area->free_list[migratetype].next,
struct page, lru);
area->nr_free--;
+ if (is_migrate_cma(migratetype))
+ area->cma_nr_free--;
new_type = try_to_steal_freepages(zone, page,
start_migratetype,
@@ -1682,6 +1692,8 @@ int __isolate_free_page(struct page *page, unsigned int
order)
/* Remove page from free list */
list_del(>lru);
zone->free_area[order].nr_free--;
+ if (is_migrate_cma(mt))
+ zone->free_area[order].cma_nr_free--;
rmv_page_order(page);
/* Set the pageblock if the isolated page is at least a pageblock */
@@ -1893,6 +1905,9 @@ static bool __zone_watermark_ok(struct zone *z, unsigned
int order,
/* free_pages may go negative - that's OK */
long min = mark;
int o;
+#ifdef CONFIG_CMA
+ bool cma_is_subbed = false;
+#endif
free_pages -= (1 << order) - 1;
if (alloc_flags & ALLOC_HIGH)
@@ -1905,8 +1920,10 @@ static bool __zone_watermark_ok(struct zone *z, unsigned
int order,
* unmovable/reclaimable allocation and they can suddenly
* vanish through CMA allocation
*/
- if (IS_ENABLED(CONFIG_CMA) && z->managed_cma_pages)
+ if (IS_ENABLED(CONFIG_CMA) && z->managed_cma_pages) {
free_pages -= zone_page_state(z, NR_FREE_CMA_PAGES);
+ cma_is_subbed = true;
+
[PATCH 1/3] CMA: Fix the bug that CMA's page number is substructed twice
In Joonsoo's CMA patch CMA: always treat free cma pages as non-free on
watermark checking [1], it changes __zone_watermark_ok to substruct CMA
pages number from free_pages if system use CMA:
if (IS_ENABLED(CONFIG_CMA) z-managed_cma_pages)
free_pages -= zone_page_state(z, NR_FREE_CMA_PAGES);
But after this part of code
for (o = 0; o order; o++) {
/* At the next order, this order's pages become unavailable */
free_pages -= z-free_area[o].nr_free o;
CMA memory in each order is part of z-free_area[o].nr_free, then the CMA
page number of this order is substructed twice. This bug will make
__zone_watermark_ok return more false.
This patch add cma_free_area to struct free_area that just record the number
of CMA pages. And add it back in the order loop to handle the substruct
twice issue.
[1] https://lkml.org/lkml/2014/5/28/110
Signed-off-by: Hui Zhu zhu...@xiaomi.com
Signed-off-by: Weixing Liu liuweix...@xiaomi.com
---
include/linux/mmzone.h | 3 +++
mm/page_alloc.c| 29 -
2 files changed, 31 insertions(+), 1 deletion(-)
diff --git a/include/linux/mmzone.h b/include/linux/mmzone.h
index ee1ce1f..7ccad93 100644
--- a/include/linux/mmzone.h
+++ b/include/linux/mmzone.h
@@ -92,6 +92,9 @@ static inline int get_pfnblock_migratetype(struct page *page,
unsigned long pfn)
struct free_area {
struct list_headfree_list[MIGRATE_TYPES];
unsigned long nr_free;
+#ifdef CONFIG_CMA
+ unsigned long cma_nr_free;
+#endif
};
struct pglist_data;
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 1b6c82c..a8d9f03 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -650,6 +650,8 @@ static inline void __free_one_page(struct page *page,
} else {
list_del(buddy-lru);
zone-free_area[order].nr_free--;
+ if (is_migrate_cma(migratetype))
+ zone-free_area[order].cma_nr_free--;
rmv_page_order(buddy);
}
combined_idx = buddy_idx page_idx;
@@ -683,6 +685,8 @@ static inline void __free_one_page(struct page *page,
list_add(page-lru, zone-free_area[order].free_list[migratetype]);
out:
zone-free_area[order].nr_free++;
+ if (is_migrate_cma(migratetype))
+ zone-free_area[order].cma_nr_free++;
}
static inline int free_pages_check(struct page *page)
@@ -987,6 +991,8 @@ static inline void expand(struct zone *zone, struct page
*page,
}
list_add(page[size].lru, area-free_list[migratetype]);
area-nr_free++;
+ if (is_migrate_cma(migratetype))
+ area-cma_nr_free++;
set_page_order(page[size], high);
}
}
@@ -1070,6 +1076,8 @@ struct page *__rmqueue_smallest(struct zone *zone,
unsigned int order,
list_del(page-lru);
rmv_page_order(page);
area-nr_free--;
+ if (is_migrate_cma(migratetype))
+ area-cma_nr_free--;
expand(zone, page, order, current_order, area, migratetype);
set_freepage_migratetype(page, migratetype);
return page;
@@ -1258,6 +1266,8 @@ __rmqueue_fallback(struct zone *zone, unsigned int order,
int start_migratetype)
page = list_entry(area-free_list[migratetype].next,
struct page, lru);
area-nr_free--;
+ if (is_migrate_cma(migratetype))
+ area-cma_nr_free--;
new_type = try_to_steal_freepages(zone, page,
start_migratetype,
@@ -1682,6 +1692,8 @@ int __isolate_free_page(struct page *page, unsigned int
order)
/* Remove page from free list */
list_del(page-lru);
zone-free_area[order].nr_free--;
+ if (is_migrate_cma(mt))
+ zone-free_area[order].cma_nr_free--;
rmv_page_order(page);
/* Set the pageblock if the isolated page is at least a pageblock */
@@ -1893,6 +1905,9 @@ static bool __zone_watermark_ok(struct zone *z, unsigned
int order,
/* free_pages may go negative - that's OK */
long min = mark;
int o;
+#ifdef CONFIG_CMA
+ bool cma_is_subbed = false;
+#endif
free_pages -= (1 order) - 1;
if (alloc_flags ALLOC_HIGH)
@@ -1905,8 +1920,10 @@ static bool __zone_watermark_ok(struct zone *z, unsigned
int order,
* unmovable/reclaimable allocation and they can suddenly
* vanish through CMA allocation
*/
- if (IS_ENABLED(CONFIG_CMA) z-managed_cma_pages)
+ if (IS_ENABLED(CONFIG_CMA) z-managed_cma_pages) {
free_pages -= zone_page_state(z, NR_FREE_CMA_PAGES);
+
