Update the hugetlb_vmemmap_restore path to take a 'batch' parameter that
indicates restoration is happening on a batch of pages. When set, use
the existing mechanism (VMEMMAP_NO_TLB_FLUSH) to delay TLB flushing.
The routine hugetlb_vmemmap_restore_folios is the only user of this new
batch parameter and it will perform a global flush after all vmemmap is
restored.
Signed-off-by: Joao Martins <joao.m.martins@xxxxxxxxxx>
Signed-off-by: Mike Kravetz <mike.kravetz@xxxxxxxxxx>
---
mm/hugetlb_vmemmap.c | 37 +++++++++++++++++++++++--------------
1 file changed, 23 insertions(+), 14 deletions(-)
diff --git a/mm/hugetlb_vmemmap.c b/mm/hugetlb_vmemmap.c
index 8c85e2c38538..11fda9d061eb 100644
--- a/mm/hugetlb_vmemmap.c
+++ b/mm/hugetlb_vmemmap.c
@@ -458,17 +458,19 @@ static int alloc_vmemmap_page_list(unsigned long start, unsigned long end,
* @end: end address of the vmemmap virtual address range that we want to
* remap.
* @reuse: reuse address.
+ * @flags: modify behavior for bulk operations
*
* Return: %0 on success, negative error code otherwise.
*/
static int vmemmap_remap_alloc(unsigned long start, unsigned long end,
- unsigned long reuse)
+ unsigned long reuse, unsigned long flags)
{
LIST_HEAD(vmemmap_pages);
struct vmemmap_remap_walk walk = {
.remap_pte = vmemmap_restore_pte,
.reuse_addr = reuse,
.vmemmap_pages = &vmemmap_pages,
+ .flags = flags,
};
/* See the comment in the vmemmap_remap_free(). */
@@ -490,17 +492,7 @@ EXPORT_SYMBOL(hugetlb_optimize_vmemmap_key);
static bool vmemmap_optimize_enabled = IS_ENABLED(CONFIG_HUGETLB_PAGE_OPTIMIZE_VMEMMAP_DEFAULT_ON);
core_param(hugetlb_free_vmemmap, vmemmap_optimize_enabled, bool, 0);
-/**
- * hugetlb_vmemmap_restore - restore previously optimized (by
- * hugetlb_vmemmap_optimize()) vmemmap pages which
- * will be reallocated and remapped.
- * @h: struct hstate.
- * @head: the head page whose vmemmap pages will be restored.
- *
- * Return: %0 if @head's vmemmap pages have been reallocated and remapped,
- * negative error code otherwise.
- */
-int hugetlb_vmemmap_restore(const struct hstate *h, struct page *head)
+static int __hugetlb_vmemmap_restore(const struct hstate *h, struct page *head, unsigned long flags)
{
int ret;
unsigned long vmemmap_start = (unsigned long)head, vmemmap_end;
@@ -521,7 +513,7 @@ int hugetlb_vmemmap_restore(const struct hstate *h, struct page *head)
* When a HugeTLB page is freed to the buddy allocator, previously
* discarded vmemmap pages must be allocated and remapping.
*/
- ret = vmemmap_remap_alloc(vmemmap_start, vmemmap_end, vmemmap_reuse);
+ ret = vmemmap_remap_alloc(vmemmap_start, vmemmap_end, vmemmap_reuse, flags);
if (!ret) {
ClearHPageVmemmapOptimized(head);
static_branch_dec(&hugetlb_optimize_vmemmap_key);
@@ -530,6 +522,21 @@ int hugetlb_vmemmap_restore(const struct hstate *h, struct page *head)
return ret;
}
+/**
+ * hugetlb_vmemmap_restore - restore previously optimized (by
+ * hugetlb_vmemmap_optimize()) vmemmap pages which
+ * will be reallocated and remapped.
+ * @h: struct hstate.
+ * @head: the head page whose vmemmap pages will be restored.
+ *
+ * Return: %0 if @head's vmemmap pages have been reallocated and remapped,
+ * negative error code otherwise.
+ */
+int hugetlb_vmemmap_restore(const struct hstate *h, struct page *head)
+{
+ return __hugetlb_vmemmap_restore(h, head, 0UL);
+}
+
/*
* This function will attempt to resore vmemmap for a list of folios. There
* is no guarantee that restoration will be successful for all or any folios.
@@ -540,7 +547,9 @@ void hugetlb_vmemmap_restore_folios(const struct hstate *h, struct list_head *fo
struct folio *folio;
list_for_each_entry(folio, folio_list, lru)
- (void)hugetlb_vmemmap_restore(h, &folio->page);
+ (void)__hugetlb_vmemmap_restore(h, &folio->page, VMEMMAP_NO_TLB_FLUSH);
+
+ flush_tlb_all();
}
/* Return true iff a HugeTLB whose vmemmap should and can be optimized. */
--
2.41.0
