From: Zi Yan <ziy@xxxxxxxxxx>
It supports copying a list of pages via multi-threaded process.
It evenly distributes a list of pages to a group of threads and
uses the same subroutine as copy_page_mthread()
Signed-off-by: Zi Yan <ziy@xxxxxxxxxx>
---
mm/copy_pages.c | 62 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++
mm/internal.h | 3 +++
2 files changed, 65 insertions(+)
diff --git a/mm/copy_pages.c b/mm/copy_pages.c
index c357e7b01042..516c0a1a57f3 100644
--- a/mm/copy_pages.c
+++ b/mm/copy_pages.c
@@ -84,3 +84,65 @@ int copy_pages_mthread(struct page *to, struct page *from, int nr_pages)
kfree(work_items);
return 0;
}
+
+int copy_page_lists_mthread(struct page **to, struct page **from, int nr_pages)
+{
+ int err = 0;
+ unsigned int cthreads, node = page_to_nid(*to);
+ int i;
+ struct copy_info *work_items;
+ int nr_pages_per_page = hpage_nr_pages(*from);
+ const struct cpumask *cpumask = cpumask_of_node(node);
+ int cpu_id_list[32] = {0};
+ int cpu;
+
+ cthreads = nr_copythreads;
+ cthreads = min_t(unsigned int, cthreads, cpumask_weight(cpumask));
+ cthreads = (cthreads / 2) * 2;
+ cthreads = min_t(unsigned int, nr_pages, cthreads);
+
+ work_items = kzalloc(sizeof(struct copy_info)*nr_pages,
+ GFP_KERNEL);
+ if (!work_items)
+ return -ENOMEM;
+
+ i = 0;
+ for_each_cpu(cpu, cpumask) {
+ if (i >= cthreads)
+ break;
+ cpu_id_list[i] = cpu;
+ ++i;
+ }
+
+ for (i = 0; i < nr_pages; ++i) {
+ int thread_idx = i % cthreads;
+
+ INIT_WORK((struct work_struct *)&work_items[i],
+ copythread);
+
+ work_items[i].to = kmap(to[i]);
+ work_items[i].from = kmap(from[i]);
+ work_items[i].chunk_size = PAGE_SIZE * hpage_nr_pages(from[i]);
+
+ BUG_ON(nr_pages_per_page != hpage_nr_pages(from[i]));
+ BUG_ON(nr_pages_per_page != hpage_nr_pages(to[i]));
+
+
+ queue_work_on(cpu_id_list[thread_idx],
+ system_highpri_wq,
+ (struct work_struct *)&work_items[i]);
+ }
+
+ /* Wait until it finishes */
+ for (i = 0; i < cthreads; ++i)
+ flush_work((struct work_struct *) &work_items[i]);
+
+ for (i = 0; i < nr_pages; ++i) {
+ kunmap(to[i]);
+ kunmap(from[i]);
+ }
+
+ kfree(work_items);
+
+ return err;
+}
diff --git a/mm/internal.h b/mm/internal.h
index ccfc2a2969f4..175e08ed524a 100644
--- a/mm/internal.h
+++ b/mm/internal.h
@@ -498,4 +498,7 @@ extern const struct trace_print_flags pageflag_names[];
extern const struct trace_print_flags vmaflag_names[];
extern const struct trace_print_flags gfpflag_names[];
+extern int copy_page_lists_mthread(struct page **to,
+ struct page **from, int nr_pages);
+
#endif /* __MM_INTERNAL_H */
--
2.11.0
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