| Message ID | 20230621073912.21747-1-liuq131@chinatelecom.cn (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | [v2] mm/min_free_kbytes: modify min_free_kbytes calculation rules | expand |
Hi, Liuq, Thanks for updated patch. liuq <liuq131@chinatelecom.cn> writes: > The current calculation of min_free_kbytes only uses ZONE_DMA and > ZONE_NORMAL pages,but the ZONE_MOVABLE zone->_watermark[WMARK_MIN] > will also divide part of min_free_kbytes.This will cause the min > watermark of ZONE_NORMAL to be too small in the presence of ZONE_MOVEABLE. > > __GFP_HIGH and PF_MEMALLOC allocations usually don't need moveable > zone pages, so just like ZONE_HIGHMEM, cap pages_min to a small > value in __setup_per_zone_wmarks. Please list the test result of your patch. That is, WMARK_MIN before and after your patch in a system with large ZONE_MOVABLE. > Signed-off-by: liuq <liuq131@chinatelecom.cn> > --- > mm/page_alloc.c | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/mm/page_alloc.c b/mm/page_alloc.c > index 47421bedc12b..608384712a89 100644 > --- a/mm/page_alloc.c > +++ b/mm/page_alloc.c > @@ -6364,7 +6364,7 @@ static void __setup_per_zone_wmarks(void) > > /* Calculate total number of !ZONE_HIGHMEM pages */ > for_each_zone(zone) { > - if (!is_highmem(zone)) > + if (!is_highmem(zone) || zone_idx(zone) != ZONE_MOVABLE) > lowmem_pages += zone_managed_pages(zone); > } > > @@ -6374,7 +6374,7 @@ static void __setup_per_zone_wmarks(void) > spin_lock_irqsave(&zone->lock, flags); > tmp = (u64)pages_min * zone_managed_pages(zone); > do_div(tmp, lowmem_pages); > - if (is_highmem(zone)) { > + if (is_highmem(zone) || zone_idx(zone) == ZONE_MOVABLE) { > /* > * __GFP_HIGH and PF_MEMALLOC allocations usually don't > * need highmem pages, so cap pages_min to a small ~~~~~~~ Change the comments above too? Best Regards, Huang, Ying
On 21.06.23 09:39, liuq wrote: > The current calculation of min_free_kbytes only uses ZONE_DMA and > ZONE_NORMAL pages,but the ZONE_MOVABLE zone->_watermark[WMARK_MIN] > will also divide part of min_free_kbytes.This will cause the min > watermark of ZONE_NORMAL to be too small in the presence of ZONE_MOVEABLE. > > __GFP_HIGH and PF_MEMALLOC allocations usually don't need moveable > zone pages, so just like ZONE_HIGHMEM, cap pages_min to a small > value in __setup_per_zone_wmarks. > > Signed-off-by: liuq <liuq131@chinatelecom.cn> > --- > mm/page_alloc.c | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/mm/page_alloc.c b/mm/page_alloc.c > index 47421bedc12b..608384712a89 100644 > --- a/mm/page_alloc.c > +++ b/mm/page_alloc.c > @@ -6364,7 +6364,7 @@ static void __setup_per_zone_wmarks(void) > > /* Calculate total number of !ZONE_HIGHMEM pages */ > for_each_zone(zone) { > - if (!is_highmem(zone)) > + if (!is_highmem(zone) || zone_idx(zone) != ZONE_MOVABLE) > lowmem_pages += zone_managed_pages(zone); > } > > @@ -6374,7 +6374,7 @@ static void __setup_per_zone_wmarks(void) > spin_lock_irqsave(&zone->lock, flags); > tmp = (u64)pages_min * zone_managed_pages(zone); > do_div(tmp, lowmem_pages); > - if (is_highmem(zone)) { > + if (is_highmem(zone) || zone_idx(zone) == ZONE_MOVABLE) { > /* > * __GFP_HIGH and PF_MEMALLOC allocations usually don't > * need highmem pages, so cap pages_min to a small Patch subject should probably be something like "mm/page_alloc: fix min_free_kbytes calculation regarding ZONE_MOVABLE" ?
diff --git a/mm/page_alloc.c b/mm/page_alloc.c index 47421bedc12b..608384712a89 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -6364,7 +6364,7 @@ static void __setup_per_zone_wmarks(void) /* Calculate total number of !ZONE_HIGHMEM pages */ for_each_zone(zone) { - if (!is_highmem(zone)) + if (!is_highmem(zone) || zone_idx(zone) != ZONE_MOVABLE) lowmem_pages += zone_managed_pages(zone); } @@ -6374,7 +6374,7 @@ static void __setup_per_zone_wmarks(void) spin_lock_irqsave(&zone->lock, flags); tmp = (u64)pages_min * zone_managed_pages(zone); do_div(tmp, lowmem_pages); - if (is_highmem(zone)) { + if (is_highmem(zone) || zone_idx(zone) == ZONE_MOVABLE) { /* * __GFP_HIGH and PF_MEMALLOC allocations usually don't * need highmem pages, so cap pages_min to a small
The current calculation of min_free_kbytes only uses ZONE_DMA and ZONE_NORMAL pages,but the ZONE_MOVABLE zone->_watermark[WMARK_MIN] will also divide part of min_free_kbytes.This will cause the min watermark of ZONE_NORMAL to be too small in the presence of ZONE_MOVEABLE. __GFP_HIGH and PF_MEMALLOC allocations usually don't need moveable zone pages, so just like ZONE_HIGHMEM, cap pages_min to a small value in __setup_per_zone_wmarks. Signed-off-by: liuq <liuq131@chinatelecom.cn> --- mm/page_alloc.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)