Move pageblock_start_pfn/pageblock_end_pfn() into pageblock-flags.h,
then they could be used somewhere else, not only in compaction.
Signed-off-by: Kefeng Wang <[email protected]>
---
include/linux/pageblock-flags.h | 2 ++
mm/compaction.c | 2 --
mm/memblock.c | 2 +-
mm/page_alloc.c | 13 ++++++-------
mm/page_isolation.c | 2 +-
mm/page_owner.c | 4 ++--
6 files changed, 12 insertions(+), 13 deletions(-)
diff --git a/include/linux/pageblock-flags.h b/include/linux/pageblock-flags.h
index 83c7248053a1..ef2e17e312ae 100644
--- a/include/linux/pageblock-flags.h
+++ b/include/linux/pageblock-flags.h
@@ -53,6 +53,8 @@ extern unsigned int pageblock_order;
#endif /* CONFIG_HUGETLB_PAGE */
#define pageblock_nr_pages (1UL << pageblock_order)
+#define pageblock_start_pfn(pfn) round_down(pfn, pageblock_nr_pages)
+#define pageblock_end_pfn(pfn) ALIGN((pfn + 1), pageblock_nr_pages)
/* Forward declaration */
struct page;
diff --git a/mm/compaction.c b/mm/compaction.c
index f72907c7cfef..65bef5f78897 100644
--- a/mm/compaction.c
+++ b/mm/compaction.c
@@ -52,8 +52,6 @@ static inline void count_compact_events(enum vm_event_item item, long delta)
#define block_start_pfn(pfn, order) round_down(pfn, 1UL << (order))
#define block_end_pfn(pfn, order) ALIGN((pfn) + 1, 1UL << (order))
-#define pageblock_start_pfn(pfn) block_start_pfn(pfn, pageblock_order)
-#define pageblock_end_pfn(pfn) block_end_pfn(pfn, pageblock_order)
/*
* Page order with-respect-to which proactive compaction
diff --git a/mm/memblock.c b/mm/memblock.c
index b5d3026979fc..46fe7575f03c 100644
--- a/mm/memblock.c
+++ b/mm/memblock.c
@@ -2000,7 +2000,7 @@ static void __init free_unused_memmap(void)
* presume that there are no holes in the memory map inside
* a pageblock
*/
- start = round_down(start, pageblock_nr_pages);
+ start = pageblock_start_pfn(start);
/*
* If we had a previous bank, and there is a space
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 36b20215a3be..93339cc61f92 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -544,7 +544,7 @@ static inline int pfn_to_bitidx(const struct page *page, unsigned long pfn)
#ifdef CONFIG_SPARSEMEM
pfn &= (PAGES_PER_SECTION-1);
#else
- pfn = pfn - round_down(page_zone(page)->zone_start_pfn, pageblock_nr_pages);
+ pfn = pfn - pageblock_start_pfn(page_zone(page)->zone_start_pfn);
#endif /* CONFIG_SPARSEMEM */
return (pfn >> pageblock_order) * NR_PAGEBLOCK_BITS;
}
@@ -1857,7 +1857,7 @@ void set_zone_contiguous(struct zone *zone)
unsigned long block_start_pfn = zone->zone_start_pfn;
unsigned long block_end_pfn;
- block_end_pfn = ALIGN(block_start_pfn + 1, pageblock_nr_pages);
+ block_end_pfn = pageblock_end_pfn(block_start_pfn);
for (; block_start_pfn < zone_end_pfn(zone);
block_start_pfn = block_end_pfn,
block_end_pfn += pageblock_nr_pages) {
@@ -2653,8 +2653,8 @@ int move_freepages_block(struct zone *zone, struct page *page,
*num_movable = 0;
pfn = page_to_pfn(page);
- start_pfn = pfn & ~(pageblock_nr_pages - 1);
- end_pfn = start_pfn + pageblock_nr_pages - 1;
+ start_pfn = pageblock_start_pfn(pfn);
+ end_pfn = pageblock_end_pfn(pfn) - 1;
/* Do not cross zone boundaries */
if (!zone_spans_pfn(zone, start_pfn))
@@ -6939,9 +6939,8 @@ static void __init init_unavailable_range(unsigned long spfn,
u64 pgcnt = 0;
for (pfn = spfn; pfn < epfn; pfn++) {
- if (!pfn_valid(ALIGN_DOWN(pfn, pageblock_nr_pages))) {
- pfn = ALIGN_DOWN(pfn, pageblock_nr_pages)
- + pageblock_nr_pages - 1;
+ if (!pfn_valid(pageblock_start_pfn(pfn))) {
+ pfn = pageblock_end_pfn(pfn) - 1;
continue;
}
__init_single_page(pfn_to_page(pfn), pfn, zone, node);
diff --git a/mm/page_isolation.c b/mm/page_isolation.c
index 9d73dc38e3d7..f2df4ad53cd6 100644
--- a/mm/page_isolation.c
+++ b/mm/page_isolation.c
@@ -172,7 +172,7 @@ static int set_migratetype_isolate(struct page *page, int migratetype, int isol_
* to avoid redundant checks.
*/
check_unmovable_start = max(page_to_pfn(page), start_pfn);
- check_unmovable_end = min(ALIGN(page_to_pfn(page) + 1, pageblock_nr_pages),
+ check_unmovable_end = min(pageblock_end_pfn(page_to_pfn(page)),
end_pfn);
unmovable = has_unmovable_pages(check_unmovable_start, check_unmovable_end,
diff --git a/mm/page_owner.c b/mm/page_owner.c
index 90023f938c19..c91664a4b768 100644
--- a/mm/page_owner.c
+++ b/mm/page_owner.c
@@ -297,7 +297,7 @@ void pagetypeinfo_showmixedcount_print(struct seq_file *m,
continue;
}
- block_end_pfn = ALIGN(pfn + 1, pageblock_nr_pages);
+ block_end_pfn = pageblock_end_pfn(pfn);
block_end_pfn = min(block_end_pfn, end_pfn);
pageblock_mt = get_pageblock_migratetype(page);
@@ -637,7 +637,7 @@ static void init_pages_in_zone(pg_data_t *pgdat, struct zone *zone)
continue;
}
- block_end_pfn = ALIGN(pfn + 1, pageblock_nr_pages);
+ block_end_pfn = pageblock_end_pfn(pfn);
block_end_pfn = min(block_end_pfn, end_pfn);
for (; pfn < block_end_pfn; pfn++) {
--
2.35.3
Add pageblock_aligned() and use it to simplify code.
Signed-off-by: Kefeng Wang <[email protected]>
---
include/linux/pageblock-flags.h | 1 +
mm/compaction.c | 8 ++++----
mm/memory_hotplug.c | 6 ++----
mm/page_alloc.c | 17 +++++++----------
mm/page_isolation.c | 2 +-
5 files changed, 15 insertions(+), 19 deletions(-)
diff --git a/include/linux/pageblock-flags.h b/include/linux/pageblock-flags.h
index ef2e17e312ae..e0b980268442 100644
--- a/include/linux/pageblock-flags.h
+++ b/include/linux/pageblock-flags.h
@@ -53,6 +53,7 @@ extern unsigned int pageblock_order;
#endif /* CONFIG_HUGETLB_PAGE */
#define pageblock_nr_pages (1UL << pageblock_order)
+#define pageblock_aligned(pfn) IS_ALIGNED((unsigned long)(pfn), pageblock_nr_pages)
#define pageblock_start_pfn(pfn) round_down(pfn, pageblock_nr_pages)
#define pageblock_end_pfn(pfn) ALIGN((pfn + 1), pageblock_nr_pages)
diff --git a/mm/compaction.c b/mm/compaction.c
index 65bef5f78897..c4e4453187a2 100644
--- a/mm/compaction.c
+++ b/mm/compaction.c
@@ -402,7 +402,7 @@ static bool test_and_set_skip(struct compact_control *cc, struct page *page,
if (cc->ignore_skip_hint)
return false;
- if (!IS_ALIGNED(pfn, pageblock_nr_pages))
+ if (!pageblock_aligned(pfn))
return false;
skip = get_pageblock_skip(page);
@@ -884,7 +884,7 @@ isolate_migratepages_block(struct compact_control *cc, unsigned long low_pfn,
* COMPACT_CLUSTER_MAX at a time so the second call must
* not falsely conclude that the block should be skipped.
*/
- if (!valid_page && IS_ALIGNED(low_pfn, pageblock_nr_pages)) {
+ if (!valid_page && pageblock_aligned(low_pfn)) {
if (!isolation_suitable(cc, page)) {
low_pfn = end_pfn;
page = NULL;
@@ -1936,7 +1936,7 @@ static isolate_migrate_t isolate_migratepages(struct compact_control *cc)
* before making it "skip" so other compaction instances do
* not scan the same block.
*/
- if (IS_ALIGNED(low_pfn, pageblock_nr_pages) &&
+ if (pageblock_aligned(low_pfn) &&
!fast_find_block && !isolation_suitable(cc, page))
continue;
@@ -2122,7 +2122,7 @@ static enum compact_result __compact_finished(struct compact_control *cc)
* migration source is unmovable/reclaimable but it's not worth
* special casing.
*/
- if (!IS_ALIGNED(cc->migrate_pfn, pageblock_nr_pages))
+ if (!pageblock_aligned(cc->migrate_pfn))
return COMPACT_CONTINUE;
/* Direct compactor: Is a suitable page free? */
diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c
index 9ae1f98548b1..fd40f7e9f176 100644
--- a/mm/memory_hotplug.c
+++ b/mm/memory_hotplug.c
@@ -1085,8 +1085,7 @@ int __ref online_pages(unsigned long pfn, unsigned long nr_pages,
* of the physical memory space for vmemmaps. That space is pageblock
* aligned.
*/
- if (WARN_ON_ONCE(!nr_pages ||
- !IS_ALIGNED(pfn, pageblock_nr_pages) ||
+ if (WARN_ON_ONCE(!nr_pages || !pageblock_aligned(pfn) ||
!IS_ALIGNED(pfn + nr_pages, PAGES_PER_SECTION)))
return -EINVAL;
@@ -1806,8 +1805,7 @@ int __ref offline_pages(unsigned long start_pfn, unsigned long nr_pages,
* of the physical memory space for vmemmaps. That space is pageblock
* aligned.
*/
- if (WARN_ON_ONCE(!nr_pages ||
- !IS_ALIGNED(start_pfn, pageblock_nr_pages) ||
+ if (WARN_ON_ONCE(!nr_pages || !pageblock_aligned(start_pfn) ||
!IS_ALIGNED(start_pfn + nr_pages, PAGES_PER_SECTION)))
return -EINVAL;
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 93339cc61f92..d030c20a6081 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -1892,15 +1892,14 @@ static void __init deferred_free_range(unsigned long pfn,
page = pfn_to_page(pfn);
/* Free a large naturally-aligned chunk if possible */
- if (nr_pages == pageblock_nr_pages &&
- (pfn & (pageblock_nr_pages - 1)) == 0) {
+ if (nr_pages == pageblock_nr_pages && pageblock_aligned(pfn)) {
set_pageblock_migratetype(page, MIGRATE_MOVABLE);
__free_pages_core(page, pageblock_order);
return;
}
for (i = 0; i < nr_pages; i++, page++, pfn++) {
- if ((pfn & (pageblock_nr_pages - 1)) == 0)
+ if (pageblock_aligned(pfn))
set_pageblock_migratetype(page, MIGRATE_MOVABLE);
__free_pages_core(page, 0);
}
@@ -1928,7 +1927,7 @@ static inline void __init pgdat_init_report_one_done(void)
*/
static inline bool __init deferred_pfn_valid(unsigned long pfn)
{
- if (!(pfn & (pageblock_nr_pages - 1)) && !pfn_valid(pfn))
+ if (!pageblock_aligned(pfn) && !pfn_valid(pfn))
return false;
return true;
}
@@ -1940,14 +1939,13 @@ static inline bool __init deferred_pfn_valid(unsigned long pfn)
static void __init deferred_free_pages(unsigned long pfn,
unsigned long end_pfn)
{
- unsigned long nr_pgmask = pageblock_nr_pages - 1;
unsigned long nr_free = 0;
for (; pfn < end_pfn; pfn++) {
if (!deferred_pfn_valid(pfn)) {
deferred_free_range(pfn - nr_free, nr_free);
nr_free = 0;
- } else if (!(pfn & nr_pgmask)) {
+ } else if (!pageblock_aligned(pfn)) {
deferred_free_range(pfn - nr_free, nr_free);
nr_free = 1;
} else {
@@ -1967,7 +1965,6 @@ static unsigned long __init deferred_init_pages(struct zone *zone,
unsigned long pfn,
unsigned long end_pfn)
{
- unsigned long nr_pgmask = pageblock_nr_pages - 1;
int nid = zone_to_nid(zone);
unsigned long nr_pages = 0;
int zid = zone_idx(zone);
@@ -1977,7 +1974,7 @@ static unsigned long __init deferred_init_pages(struct zone *zone,
if (!deferred_pfn_valid(pfn)) {
page = NULL;
continue;
- } else if (!page || !(pfn & nr_pgmask)) {
+ } else if (!page || !pageblock_aligned(pfn)) {
page = pfn_to_page(pfn);
} else {
page++;
@@ -6759,7 +6756,7 @@ void __meminit memmap_init_range(unsigned long size, int nid, unsigned long zone
* such that unmovable allocations won't be scattered all
* over the place during system boot.
*/
- if (IS_ALIGNED(pfn, pageblock_nr_pages)) {
+ if (pageblock_aligned(pfn)) {
set_pageblock_migratetype(page, migratetype);
cond_resched();
}
@@ -6802,7 +6799,7 @@ static void __ref __init_zone_device_page(struct page *page, unsigned long pfn,
* Please note that MEMINIT_HOTPLUG path doesn't clear memmap
* because this is done early in section_activate()
*/
- if (IS_ALIGNED(pfn, pageblock_nr_pages)) {
+ if (pageblock_aligned(pfn)) {
set_pageblock_migratetype(page, MIGRATE_MOVABLE);
cond_resched();
}
diff --git a/mm/page_isolation.c b/mm/page_isolation.c
index f2df4ad53cd6..13cc00598677 100644
--- a/mm/page_isolation.c
+++ b/mm/page_isolation.c
@@ -311,7 +311,7 @@ static int isolate_single_pageblock(unsigned long boundary_pfn, int flags,
struct zone *zone;
int ret;
- VM_BUG_ON(!IS_ALIGNED(boundary_pfn, pageblock_nr_pages));
+ VM_BUG_ON(!pageblock_aligned(boundary_pfn));
if (isolate_before)
isolate_pageblock = boundary_pfn - pageblock_nr_pages;
--
2.35.3
On 2022/9/2 16:20, David Hildenbrand wrote:
> On 02.09.22 08:47, Kefeng Wang wrote:
>> Move pageblock_start_pfn/pageblock_end_pfn() into pageblock-flags.h,
>> then they could be used somewhere else, not only in compaction.
>>
>> Signed-off-by: Kefeng Wang <[email protected]>
>> ---
>> include/linux/pageblock-flags.h | 2 ++
>> mm/compaction.c | 2 --
>> mm/memblock.c | 2 +-
>> mm/page_alloc.c | 13 ++++++-------
>> mm/page_isolation.c | 2 +-
>> mm/page_owner.c | 4 ++--
>> 6 files changed, 12 insertions(+), 13 deletions(-)
>>
>> diff --git a/include/linux/pageblock-flags.h b/include/linux/pageblock-flags.h
>> index 83c7248053a1..ef2e17e312ae 100644
>> --- a/include/linux/pageblock-flags.h
>> +++ b/include/linux/pageblock-flags.h
>> @@ -53,6 +53,8 @@ extern unsigned int pageblock_order;
>> #endif /* CONFIG_HUGETLB_PAGE */
>>
>> #define pageblock_nr_pages (1UL << pageblock_order)
>> +#define pageblock_start_pfn(pfn) round_down(pfn, pageblock_nr_pages)
>> +#define pageblock_end_pfn(pfn) ALIGN((pfn + 1), pageblock_nr_pages)
>>
> I'd naturally have paired ALIGN with ALIGN_DOWN -- or round_up with round_down.
> (You're replacing one instance where ALIGN_DOWN was used at least.)
I think they are same for pageblock usage，but the original macro
introduced from Vlastimil
(06b6640a3902 mm, compaction: wrap calculating first and last pfn of
pageblock), let's
wait for Vlastimil to see if there are some background.
>
> But maybe there is an obvious reason that I am missing :)
>
>> /* Forward declaration */
>> struct page;
>> diff --git a/mm/compaction.c b/mm/compaction.c
>> index f72907c7cfef..65bef5f78897 100644
>> --- a/mm/compaction.c
>> +++ b/mm/compaction.c
>> @@ -52,8 +52,6 @@ static inline void count_compact_events(enum vm_event_item item, long delta)
>>
>> #define block_start_pfn(pfn, order) round_down(pfn, 1UL << (order))
>> #define block_end_pfn(pfn, order) ALIGN((pfn) + 1, 1UL << (order))
>> -#define pageblock_start_pfn(pfn) block_start_pfn(pfn, pageblock_order)
>> -#define pageblock_end_pfn(pfn) block_end_pfn(pfn, pageblock_order)
>>
>> /*
>> * Page order with-respect-to which proactive compaction
>> diff --git a/mm/memblock.c b/mm/memblock.c
>> index b5d3026979fc..46fe7575f03c 100644
>> --- a/mm/memblock.c
>> +++ b/mm/memblock.c
>> @@ -2000,7 +2000,7 @@ static void __init free_unused_memmap(void)
>> * presume that there are no holes in the memory map inside
>> * a pageblock
>> */
>> - start = round_down(start, pageblock_nr_pages);
>> + start = pageblock_start_pfn(start);
>>
>> /*
>> * If we had a previous bank, and there is a space
>> diff --git a/mm/page_alloc.c b/mm/page_alloc.c
>> index 36b20215a3be..93339cc61f92 100644
>> --- a/mm/page_alloc.c
>> +++ b/mm/page_alloc.c
>> @@ -544,7 +544,7 @@ static inline int pfn_to_bitidx(const struct page *page, unsigned long pfn)
>> #ifdef CONFIG_SPARSEMEM
>> pfn &= (PAGES_PER_SECTION-1);
>> #else
>> - pfn = pfn - round_down(page_zone(page)->zone_start_pfn, pageblock_nr_pages);
>> + pfn = pfn - pageblock_start_pfn(page_zone(page)->zone_start_pfn);
>> #endif /* CONFIG_SPARSEMEM */
>> return (pfn >> pageblock_order) * NR_PAGEBLOCK_BITS;
>> }
>> @@ -1857,7 +1857,7 @@ void set_zone_contiguous(struct zone *zone)
>> unsigned long block_start_pfn = zone->zone_start_pfn;
>> unsigned long block_end_pfn;
>>
>> - block_end_pfn = ALIGN(block_start_pfn + 1, pageblock_nr_pages);
>> + block_end_pfn = pageblock_end_pfn(block_start_pfn);
>> for (; block_start_pfn < zone_end_pfn(zone);
>> block_start_pfn = block_end_pfn,
>> block_end_pfn += pageblock_nr_pages) {
>> @@ -2653,8 +2653,8 @@ int move_freepages_block(struct zone *zone, struct page *page,
>> *num_movable = 0;
>>
>> pfn = page_to_pfn(page);
>> - start_pfn = pfn & ~(pageblock_nr_pages - 1);
>> - end_pfn = start_pfn + pageblock_nr_pages - 1;
>> + start_pfn = pageblock_start_pfn(pfn);
>> + end_pfn = pageblock_end_pfn(pfn) - 1;
>>
>> /* Do not cross zone boundaries */
>> if (!zone_spans_pfn(zone, start_pfn))
>> @@ -6939,9 +6939,8 @@ static void __init init_unavailable_range(unsigned long spfn,
>> u64 pgcnt = 0;
>>
>> for (pfn = spfn; pfn < epfn; pfn++) {
>> - if (!pfn_valid(ALIGN_DOWN(pfn, pageblock_nr_pages))) {
>> - pfn = ALIGN_DOWN(pfn, pageblock_nr_pages)
>> - + pageblock_nr_pages - 1;
>> + if (!pfn_valid(pageblock_start_pfn(pfn))) {
>> + pfn = pageblock_end_pfn(pfn) - 1;
>> continue;
>> }
>> __init_single_page(pfn_to_page(pfn), pfn, zone, node);
>> diff --git a/mm/page_isolation.c b/mm/page_isolation.c
>> index 9d73dc38e3d7..f2df4ad53cd6 100644
>> --- a/mm/page_isolation.c
>> +++ b/mm/page_isolation.c
>> @@ -172,7 +172,7 @@ static int set_migratetype_isolate(struct page *page, int migratetype, int isol_
>> * to avoid redundant checks.
>> */
>> check_unmovable_start = max(page_to_pfn(page), start_pfn);
>> - check_unmovable_end = min(ALIGN(page_to_pfn(page) + 1, pageblock_nr_pages),
>> + check_unmovable_end = min(pageblock_end_pfn(page_to_pfn(page)),
>> end_pfn);
>>
>
> There are some more cases that might need care as well:
>
>
> mm/memblock.c: prev_end = ALIGN(end, pageblock_nr_pages);
> mm/memblock.c: prev_end = ALIGN(end, pageblock_nr_pages);
> mm/page_isolation.c: VM_BUG_ON(ALIGN_DOWN(start_pfn, pageblock_nr_pages) !=
> mm/page_isolation.c: ALIGN_DOWN(end_pfn - 1, pageblock_nr_pages));
> mm/page_isolation.c: unsigned long isolate_start = ALIGN_DOWN(start_pfn, pageblock_nr_pages);
> mm/page_isolation.c: unsigned long isolate_end = ALIGN(end_pfn, pageblock_nr_pages);
> mm/page_isolation.c: unsigned long isolate_start = ALIGN_DOWN(start_pfn, pageblock_nr_pages);
> mm/page_isolation.c: unsigned long isolate_end = ALIGN(end_pfn, pageblock_nr_pages);
ok, will update.
>
>
>
On 02.09.22 11:02, Kefeng Wang wrote:
>
> On 2022/9/2 16:42, David Hildenbrand wrote:
>> On 02.09.22 08:47, Kefeng Wang wrote:
>>> Add pageblock_aligned() and use it to simplify code.
>>>
>>> Signed-off-by: Kefeng Wang <[email protected]>
>>> ---
>> [...]
>>
>>> - unsigned long nr_pgmask = pageblock_nr_pages - 1;
>>> int nid = zone_to_nid(zone);
>>> unsigned long nr_pages = 0;
>>> int zid = zone_idx(zone);
>>> @@ -1977,7 +1974,7 @@ static unsigned long __init deferred_init_pages(struct zone *zone,
>>> if (!deferred_pfn_valid(pfn)) {
>>> page = NULL;
>>> continue;
>>> - } else if (!page || !(pfn & nr_pgmask)) {
>> I didn't sleep too well this night and am tired, please tell me why I'm
>> wrong :)
> Wish you have a good reset :)
Thanks, the headache isn't helping :D
>> "pfn & (pageblock_nr_pages - 1)" is true if the pageblock is not aligned
>>
>> E.g., pfn = 1, pageblock_nr_pages = 512
>>
>> pfn & (pageblock_nr_pages - 1)
>> -> 1 & (512 - 1)
>> -> 1 & 511
>> -> true
>>
>> "!(pfn & (pageblock_nr_pages - 1))" is true if the pageblock is aligned
>> -> !(true)
>> -> false
>>
>>
>> However, "!pageblock_aligned(1)" = true
>>
>>
>>> + } else if (!page || !pageblock_aligned(pfn)) {
>
> pageblock_aligned(pfn) IS_ALIGNED((unsigned long)(pfn), pageblock_nr_pages)
>
> #define IS_ALIGNED(x, a) (((x) & ((typeof(x))(a) - 1)) == 0) (((pfn) &
> (pageblock_nr_pages - 1)) == 0) -> ((1 & 512 -1) == 0) -> ((1 & 511) ==
> 0) -> ((511) == 0) -> false
> right ?
yes ... and inverting that would give you "true", which is not what we want?
Again, sorry if I'm wrong ...
--
Thanks,
David / dhildenb
On 02.09.22 08:47, Kefeng Wang wrote:
> Add pageblock_aligned() and use it to simplify code.
>
> Signed-off-by: Kefeng Wang <[email protected]>
> ---
[...]
> - unsigned long nr_pgmask = pageblock_nr_pages - 1;
> int nid = zone_to_nid(zone);
> unsigned long nr_pages = 0;
> int zid = zone_idx(zone);
> @@ -1977,7 +1974,7 @@ static unsigned long __init deferred_init_pages(struct zone *zone,
> if (!deferred_pfn_valid(pfn)) {
> page = NULL;
> continue;
> - } else if (!page || !(pfn & nr_pgmask)) {
I didn't sleep too well this night and am tired, please tell me why I'm
wrong :)
"pfn & (pageblock_nr_pages - 1)" is true if the pageblock is not aligned
E.g., pfn = 1, pageblock_nr_pages = 512
pfn & (pageblock_nr_pages - 1)
-> 1 & (512 - 1)
-> 1 & 511
-> true
"!(pfn & (pageblock_nr_pages - 1))" is true if the pageblock is aligned
-> !(true)
-> false
However, "!pageblock_aligned(1)" = true
> + } else if (!page || !pageblock_aligned(pfn)) {
So shouldn't this be "pageblock_aligned(pfn)"
?
> page = pfn_to_page(pfn);
> } else {
> page++;
--
Thanks,
David / dhildenb
On 02.09.22 08:47, Kefeng Wang wrote:
> Move pageblock_start_pfn/pageblock_end_pfn() into pageblock-flags.h,
> then they could be used somewhere else, not only in compaction.
>
> Signed-off-by: Kefeng Wang <[email protected]>
> ---
> include/linux/pageblock-flags.h | 2 ++
> mm/compaction.c | 2 --
> mm/memblock.c | 2 +-
> mm/page_alloc.c | 13 ++++++-------
> mm/page_isolation.c | 2 +-
> mm/page_owner.c | 4 ++--
> 6 files changed, 12 insertions(+), 13 deletions(-)
>
> diff --git a/include/linux/pageblock-flags.h b/include/linux/pageblock-flags.h
> index 83c7248053a1..ef2e17e312ae 100644
> --- a/include/linux/pageblock-flags.h
> +++ b/include/linux/pageblock-flags.h
> @@ -53,6 +53,8 @@ extern unsigned int pageblock_order;
> #endif /* CONFIG_HUGETLB_PAGE */
>
> #define pageblock_nr_pages (1UL << pageblock_order)
> +#define pageblock_start_pfn(pfn) round_down(pfn, pageblock_nr_pages)
> +#define pageblock_end_pfn(pfn) ALIGN((pfn + 1), pageblock_nr_pages)
>
I'd naturally have paired ALIGN with ALIGN_DOWN -- or round_up with round_down.
(You're replacing one instance where ALIGN_DOWN was used at least.)
But maybe there is an obvious reason that I am missing :)
> /* Forward declaration */
> struct page;
> diff --git a/mm/compaction.c b/mm/compaction.c
> index f72907c7cfef..65bef5f78897 100644
> --- a/mm/compaction.c
> +++ b/mm/compaction.c
> @@ -52,8 +52,6 @@ static inline void count_compact_events(enum vm_event_item item, long delta)
>
> #define block_start_pfn(pfn, order) round_down(pfn, 1UL << (order))
> #define block_end_pfn(pfn, order) ALIGN((pfn) + 1, 1UL << (order))
> -#define pageblock_start_pfn(pfn) block_start_pfn(pfn, pageblock_order)
> -#define pageblock_end_pfn(pfn) block_end_pfn(pfn, pageblock_order)
>
> /*
> * Page order with-respect-to which proactive compaction
> diff --git a/mm/memblock.c b/mm/memblock.c
> index b5d3026979fc..46fe7575f03c 100644
> --- a/mm/memblock.c
> +++ b/mm/memblock.c
> @@ -2000,7 +2000,7 @@ static void __init free_unused_memmap(void)
> * presume that there are no holes in the memory map inside
> * a pageblock
> */
> - start = round_down(start, pageblock_nr_pages);
> + start = pageblock_start_pfn(start);
>
> /*
> * If we had a previous bank, and there is a space
> diff --git a/mm/page_alloc.c b/mm/page_alloc.c
> index 36b20215a3be..93339cc61f92 100644
> --- a/mm/page_alloc.c
> +++ b/mm/page_alloc.c
> @@ -544,7 +544,7 @@ static inline int pfn_to_bitidx(const struct page *page, unsigned long pfn)
> #ifdef CONFIG_SPARSEMEM
> pfn &= (PAGES_PER_SECTION-1);
> #else
> - pfn = pfn - round_down(page_zone(page)->zone_start_pfn, pageblock_nr_pages);
> + pfn = pfn - pageblock_start_pfn(page_zone(page)->zone_start_pfn);
> #endif /* CONFIG_SPARSEMEM */
> return (pfn >> pageblock_order) * NR_PAGEBLOCK_BITS;
> }
> @@ -1857,7 +1857,7 @@ void set_zone_contiguous(struct zone *zone)
> unsigned long block_start_pfn = zone->zone_start_pfn;
> unsigned long block_end_pfn;
>
> - block_end_pfn = ALIGN(block_start_pfn + 1, pageblock_nr_pages);
> + block_end_pfn = pageblock_end_pfn(block_start_pfn);
> for (; block_start_pfn < zone_end_pfn(zone);
> block_start_pfn = block_end_pfn,
> block_end_pfn += pageblock_nr_pages) {
> @@ -2653,8 +2653,8 @@ int move_freepages_block(struct zone *zone, struct page *page,
> *num_movable = 0;
>
> pfn = page_to_pfn(page);
> - start_pfn = pfn & ~(pageblock_nr_pages - 1);
> - end_pfn = start_pfn + pageblock_nr_pages - 1;
> + start_pfn = pageblock_start_pfn(pfn);
> + end_pfn = pageblock_end_pfn(pfn) - 1;
>
> /* Do not cross zone boundaries */
> if (!zone_spans_pfn(zone, start_pfn))
> @@ -6939,9 +6939,8 @@ static void __init init_unavailable_range(unsigned long spfn,
> u64 pgcnt = 0;
>
> for (pfn = spfn; pfn < epfn; pfn++) {
> - if (!pfn_valid(ALIGN_DOWN(pfn, pageblock_nr_pages))) {
> - pfn = ALIGN_DOWN(pfn, pageblock_nr_pages)
> - + pageblock_nr_pages - 1;
> + if (!pfn_valid(pageblock_start_pfn(pfn))) {
> + pfn = pageblock_end_pfn(pfn) - 1;
> continue;
> }
> __init_single_page(pfn_to_page(pfn), pfn, zone, node);
> diff --git a/mm/page_isolation.c b/mm/page_isolation.c
> index 9d73dc38e3d7..f2df4ad53cd6 100644
> --- a/mm/page_isolation.c
> +++ b/mm/page_isolation.c
> @@ -172,7 +172,7 @@ static int set_migratetype_isolate(struct page *page, int migratetype, int isol_
> * to avoid redundant checks.
> */
> check_unmovable_start = max(page_to_pfn(page), start_pfn);
> - check_unmovable_end = min(ALIGN(page_to_pfn(page) + 1, pageblock_nr_pages),
> + check_unmovable_end = min(pageblock_end_pfn(page_to_pfn(page)),
> end_pfn);
>
There are some more cases that might need care as well:
mm/memblock.c: prev_end = ALIGN(end, pageblock_nr_pages);
mm/memblock.c: prev_end = ALIGN(end, pageblock_nr_pages);
mm/page_isolation.c: VM_BUG_ON(ALIGN_DOWN(start_pfn, pageblock_nr_pages) !=
mm/page_isolation.c: ALIGN_DOWN(end_pfn - 1, pageblock_nr_pages));
mm/page_isolation.c: unsigned long isolate_start = ALIGN_DOWN(start_pfn, pageblock_nr_pages);
mm/page_isolation.c: unsigned long isolate_end = ALIGN(end_pfn, pageblock_nr_pages);
mm/page_isolation.c: unsigned long isolate_start = ALIGN_DOWN(start_pfn, pageblock_nr_pages);
mm/page_isolation.c: unsigned long isolate_end = ALIGN(end_pfn, pageblock_nr_pages);
--
Thanks,
David / dhildenb
On 2022/9/2 17:04, David Hildenbrand wrote:
> On 02.09.22 11:02, Kefeng Wang wrote:
>> On 2022/9/2 16:42, David Hildenbrand wrote:
>>> On 02.09.22 08:47, Kefeng Wang wrote:
>>>> Add pageblock_aligned() and use it to simplify code.
>>>>
>>>> Signed-off-by: Kefeng Wang <[email protected]>
>>>> ---
>>> [...]
>>>
>>>> - unsigned long nr_pgmask = pageblock_nr_pages - 1;
>>>> int nid = zone_to_nid(zone);
>>>> unsigned long nr_pages = 0;
>>>> int zid = zone_idx(zone);
>>>> @@ -1977,7 +1974,7 @@ static unsigned long __init deferred_init_pages(struct zone *zone,
>>>> if (!deferred_pfn_valid(pfn)) {
>>>> page = NULL;
>>>> continue;
>>>> - } else if (!page || !(pfn & nr_pgmask)) {
>>> I didn't sleep too well this night and am tired, please tell me why I'm
>>> wrong :)
>> Wish you have a good reset :)
> Thanks, the headache isn't helping :D
>
>>> "pfn & (pageblock_nr_pages - 1)" is true if the pageblock is not aligned
>>>
>>> E.g., pfn = 1, pageblock_nr_pages = 512
>>>
>>> pfn & (pageblock_nr_pages - 1)
>>> -> 1 & (512 - 1)
>>> -> 1 & 511
>>> -> true
>>>
>>> "!(pfn & (pageblock_nr_pages - 1))" is true if the pageblock is aligned
>>> -> !(true)
>>> -> false
>>>
>>>
>>> However, "!pageblock_aligned(1)" = true
>>>
>>>
>>>> + } else if (!page || !pageblock_aligned(pfn)) {
>> pageblock_aligned(pfn) IS_ALIGNED((unsigned long)(pfn), pageblock_nr_pages)
>>
>> #define IS_ALIGNED(x, a) (((x) & ((typeof(x))(a) - 1)) == 0) (((pfn) &
>> (pageblock_nr_pages - 1)) == 0) -> ((1 & 512 -1) == 0) -> ((1 & 511) ==
>> 0) -> ((511) == 0) -> false
>> right ?
> yes ... and inverting that would give you "true", which is not what we want?
>
oops... it's my fault, looks like I need to have a reset to save my
brain...
> Again, sorry if I'm wrong ...
>