diff --git a/include/linux/memblock.h b/include/linux/memblock.h
index f92ea77836526666b1c410423a3c15a50e1eab85..0257aee7ab4bd466019a89a7d9e3f4874c2b3420 100644
--- a/include/linux/memblock.h
+++ b/include/linux/memblock.h
@@ -416,21 +416,11 @@ static inline void early_memtest(phys_addr_t start, phys_addr_t end)
{
}
#endif
-
-extern unsigned long memblock_reserved_memory_within(phys_addr_t start_addr,
- phys_addr_t end_addr);
#else
static inline phys_addr_t memblock_alloc(phys_addr_t size, phys_addr_t align)
{
return 0;
}
-
-static inline unsigned long memblock_reserved_memory_within(phys_addr_t start_addr,
- phys_addr_t end_addr)
-{
- return 0;
-}
-
#endif /* CONFIG_HAVE_MEMBLOCK */
#endif /* __KERNEL__ */
diff --git a/mm/memblock.c b/mm/memblock.c
index 48376bd3327423fcccc308a0a6655db399611510..f7f76513a0c5ea8154e45a49b896b6fd4affe1f8 100644
--- a/mm/memblock.c
+++ b/mm/memblock.c
@@ -1750,29 +1750,6 @@ static void __init_memblock memblock_dump(struct memblock_type *type)
}
}
-extern unsigned long __init_memblock
-memblock_reserved_memory_within(phys_addr_t start_addr, phys_addr_t end_addr)
-{
- struct memblock_region *rgn;
- unsigned long size = 0;
- int idx;
-
- for_each_memblock_type(idx, (&memblock.reserved), rgn) {
- phys_addr_t start, end;
-
- if (rgn->base + rgn->size < start_addr)
- continue;
- if (rgn->base > end_addr)
- continue;
-
- start = rgn->base;
- end = start + rgn->size;
- size += end - start;
- }
-
- return size;
-}
-
void __init_memblock __memblock_dump_all(void)
{
pr_info("MEMBLOCK configuration:\n");
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index cf5555df78bdc6a877e118879f37f23ba1788fb7..3183eb2f579cb29a6cbb2d204e284e56c429dd33 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -292,40 +292,6 @@ EXPORT_SYMBOL(nr_online_nodes);
int page_group_by_mobility_disabled __read_mostly;
#ifdef CONFIG_DEFERRED_STRUCT_PAGE_INIT
-
-/*
- * Determine how many pages need to be initialized during early boot
- * (non-deferred initialization).
- * The value of first_deferred_pfn will be set later, once non-deferred pages
- * are initialized, but for now set it ULONG_MAX.
- */
-static inline void reset_deferred_meminit(pg_data_t *pgdat)
-{
- phys_addr_t start_addr, end_addr;
- unsigned long max_pgcnt;
- unsigned long reserved;
-
- /*
- * Initialise at least 2G of a node but also take into account that
- * two large system hashes that can take up 1GB for 0.25TB/node.
- */
- max_pgcnt = max(2UL << (30 - PAGE_SHIFT),
- (pgdat->node_spanned_pages >> 8));
-
- /*
- * Compensate the all the memblock reservations (e.g. crash kernel)
- * from the initial estimation to make sure we will initialize enough
- * memory to boot.
- */
- start_addr = PFN_PHYS(pgdat->node_start_pfn);
- end_addr = PFN_PHYS(pgdat->node_start_pfn + max_pgcnt);
- reserved = memblock_reserved_memory_within(start_addr, end_addr);
- max_pgcnt += PHYS_PFN(reserved);
-
- pgdat->static_init_pgcnt = min(max_pgcnt, pgdat->node_spanned_pages);
- pgdat->first_deferred_pfn = ULONG_MAX;
-}
-
/* Returns true if the struct page for the pfn is uninitialised */
static inline bool __meminit early_page_uninitialised(unsigned long pfn)
{
@@ -361,10 +327,6 @@ static inline bool update_defer_init(pg_data_t *pgdat,
return true;
}
#else
-static inline void reset_deferred_meminit(pg_data_t *pgdat)
-{
-}
-
static inline bool early_page_uninitialised(unsigned long pfn)
{
return false;
@@ -1611,6 +1573,117 @@ static int __init deferred_init_memmap(void *data)
pgdat_init_report_one_done();
return 0;
}
+
+/*
+ * During boot we initialize deferred pages on-demand, as needed, but once
+ * page_alloc_init_late() has finished, the deferred pages are all initialized,
+ * and we can permanently disable that path.
+ */
+static DEFINE_STATIC_KEY_TRUE(deferred_pages);
+
+/*
+ * If this zone has deferred pages, try to grow it by initializing enough
+ * deferred pages to satisfy the allocation specified by order, rounded up to
+ * the nearest PAGES_PER_SECTION boundary. So we're adding memory in increments
+ * of SECTION_SIZE bytes by initializing struct pages in increments of
+ * PAGES_PER_SECTION * sizeof(struct page) bytes.
+ *
+ * Return true when zone was grown, otherwise return false. We return true even
+ * when we grow less than requested, to let the caller decide if there are
+ * enough pages to satisfy the allocation.
+ *
+ * Note: We use noinline because this function is needed only during boot, and
+ * it is called from a __ref function _deferred_grow_zone. This way we are
+ * making sure that it is not inlined into permanent text section.
+ */
+static noinline bool __init
+deferred_grow_zone(struct zone *zone, unsigned int order)
+{
+ int zid = zone_idx(zone);
+ int nid = zone_to_nid(zone);
+ pg_data_t *pgdat = NODE_DATA(nid);
+ unsigned long nr_pages_needed = ALIGN(1 << order, PAGES_PER_SECTION);
+ unsigned long nr_pages = 0;
+ unsigned long first_init_pfn, spfn, epfn, t, flags;
+ unsigned long first_deferred_pfn = pgdat->first_deferred_pfn;
+ phys_addr_t spa, epa;
+ u64 i;
+
+ /* Only the last zone may have deferred pages */
+ if (zone_end_pfn(zone) != pgdat_end_pfn(pgdat))
+ return false;
+
+ pgdat_resize_lock(pgdat, &flags);
+
+ /*
+ * If deferred pages have been initialized while we were waiting for
+ * the lock, return true, as the zone was grown. The caller will retry
+ * this zone. We won't return to this function since the caller also
+ * has this static branch.
+ */
+ if (!static_branch_unlikely(&deferred_pages)) {
+ pgdat_resize_unlock(pgdat, &flags);
+ return true;
+ }
+
+ /*
+ * If someone grew this zone while we were waiting for spinlock, return
+ * true, as there might be enough pages already.
+ */
+ if (first_deferred_pfn != pgdat->first_deferred_pfn) {
+ pgdat_resize_unlock(pgdat, &flags);
+ return true;
+ }
+
+ first_init_pfn = max(zone->zone_start_pfn, first_deferred_pfn);
+
+ if (first_init_pfn >= pgdat_end_pfn(pgdat)) {
+ pgdat_resize_unlock(pgdat, &flags);
+ return false;
+ }
+
+ for_each_free_mem_range(i, nid, MEMBLOCK_NONE, &spa, &epa, NULL) {
+ spfn = max_t(unsigned long, first_init_pfn, PFN_UP(spa));
+ epfn = min_t(unsigned long, zone_end_pfn(zone), PFN_DOWN(epa));
+
+ while (spfn < epfn && nr_pages < nr_pages_needed) {
+ t = ALIGN(spfn + PAGES_PER_SECTION, PAGES_PER_SECTION);
+ first_deferred_pfn = min(t, epfn);
+ nr_pages += deferred_init_pages(nid, zid, spfn,
+ first_deferred_pfn);
+ spfn = first_deferred_pfn;
+ }
+
+ if (nr_pages >= nr_pages_needed)
+ break;
+ }
+
+ for_each_free_mem_range(i, nid, MEMBLOCK_NONE, &spa, &epa, NULL) {
+ spfn = max_t(unsigned long, first_init_pfn, PFN_UP(spa));
+ epfn = min_t(unsigned long, first_deferred_pfn, PFN_DOWN(epa));
+ deferred_free_pages(nid, zid, spfn, epfn);
+
+ if (first_deferred_pfn == epfn)
+ break;
+ }
+ pgdat->first_deferred_pfn = first_deferred_pfn;
+ pgdat_resize_unlock(pgdat, &flags);
+
+ return nr_pages > 0;
+}
+
+/*
+ * deferred_grow_zone() is __init, but it is called from
+ * get_page_from_freelist() during early boot until deferred_pages permanently
+ * disables this call. This is why we have refdata wrapper to avoid warning,
+ * and to ensure that the function body gets unloaded.
+ */
+static bool __ref
+_deferred_grow_zone(struct zone *zone, unsigned int order)
+{
+ return deferred_grow_zone(zone, order);
+}
+
#endif /* CONFIG_DEFERRED_STRUCT_PAGE_INIT */
void __init page_alloc_init_late(void)
@@ -1629,6 +1702,12 @@ void __init page_alloc_init_late(void)
/* Block until all are initialised */
wait_for_completion(&pgdat_init_all_done_comp);
+ /*
+ * We initialized the rest of the deferred pages. Permanently disable
+ * on-demand struct page initialization.
+ */
+ static_branch_disable(&deferred_pages);
+
/* Reinit limits that are based on free pages after the kernel is up */
files_maxfiles_init();
#endif
@@ -3208,6 +3287,16 @@ get_page_from_freelist(gfp_t gfp_mask, unsigned int order, int alloc_flags,
ac_classzone_idx(ac), alloc_flags)) {
int ret;
+#ifdef CONFIG_DEFERRED_STRUCT_PAGE_INIT
+ /*
+ * Watermark failed for this zone, but see if we can
+ * grow this zone if it contains deferred pages.
+ */
+ if (static_branch_unlikely(&deferred_pages)) {
+ if (_deferred_grow_zone(zone, order))
+ goto try_this_zone;
+ }
+#endif
/* Checked here to keep the fast path fast */
BUILD_BUG_ON(ALLOC_NO_WATERMARKS < NR_WMARK);
if (alloc_flags & ALLOC_NO_WATERMARKS)
@@ -3249,6 +3338,14 @@ get_page_from_freelist(gfp_t gfp_mask, unsigned int order, int alloc_flags,
reserve_highatomic_pageblock(page, zone, order);
return page;
+ } else {
+#ifdef CONFIG_DEFERRED_STRUCT_PAGE_INIT
+ /* Try again if zone has deferred pages */
+ if (static_branch_unlikely(&deferred_pages)) {
+ if (_deferred_grow_zone(zone, order))
+ goto try_this_zone;
+ }
+#endif
}
}
@@ -6244,7 +6341,15 @@ void __paginginit free_area_init_node(int nid, unsigned long *zones_size,
alloc_node_mem_map(pgdat);
- reset_deferred_meminit(pgdat);
+#ifdef CONFIG_DEFERRED_STRUCT_PAGE_INIT
+ /*
+ * We start only with one section of pages, more pages are added as
+ * needed until the rest of deferred pages are initialized.
+ */
+ pgdat->static_init_pgcnt = min_t(unsigned long, PAGES_PER_SECTION,
+ pgdat->node_spanned_pages);
+ pgdat->first_deferred_pfn = ULONG_MAX;
+#endif
free_area_init_core(pgdat);
}