| Message ID | 20220902064751.17890-2-wangkefeng.wang@huawei.com (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | [1/2] mm: reuse pageblock_start/end_pfn() macro | expand |
On 02.09.22 08:47, Kefeng Wang wrote: > Add pageblock_aligned() and use it to simplify code. > > Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com> > --- [...] > - 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++;
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<wangkefeng.wang@huawei.com> >> --- > [...] > >> - 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 :) > > "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 ? > > So shouldn't this be "pageblock_aligned(pfn)" > > > ? > >> page = pfn_to_page(pfn); >> } else { >> page++; >
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 <wangkefeng.wang@huawei.com> >>> --- >> [...] >> >>> - 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 ...
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 <wangkefeng.wang@huawei.com> >>>> --- >>> [...] >>> >>>> - 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 ... >
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;
Add pageblock_aligned() and use it to simplify code. Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com> --- 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(-)