thp: release page in page pre-alloc path

If NUMA is enabled, we can release the page in the page pre-alloc operation, then the CONFIG_NUMA dependent code can be reduced Signed-off-by: Xiao Guangrong <xiaoguangrong@linux.vnet.ibm.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Hugh Dickins <hughd@google.com> Cc: David Rientjes <rientjes@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

thp: release page in page pre-alloc path
If NUMA is enabled, we can release the page in the page pre-alloc operation, then the CONFIG_NUMA dependent code can be reduced Signed-off-by: Xiao Guangrong <xiaoguangrong@linux.vnet.ibm.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Hugh Dickins <hughd@google.com> Cc: David Rientjes <rientjes@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Xiao Guangrong · Linus Torvalds
1 parent d516904bd2
Showing 1 changed file with 7 additions and 12 deletions Side-by-side Diff
mm/huge_memory.c
@@ -1873,15 +1873,12 @@
 		*hpage = ERR_PTR(-ENOMEM);
 		return;
 	}
+	*hpage = new_page;
 	count_vm_event(THP_COLLAPSE_ALLOC);
 #endif
  
-	if (unlikely(mem_cgroup_newpage_charge(new_page, mm, GFP_KERNEL))) {
-#ifdef CONFIG_NUMA
-		put_page(new_page);
-#endif
+	if (unlikely(mem_cgroup_newpage_charge(new_page, mm, GFP_KERNEL)))
 		return;
-	}
  
 	/*
 	 * Prevent all access to pagetables with the exception of
  
@@ -1982,9 +1979,8 @@
 	prepare_pmd_huge_pte(pgtable, mm);
 	spin_unlock(&mm->page_table_lock);
  
-#ifndef CONFIG_NUMA
 	*hpage = NULL;
-#endif
+
 	khugepaged_pages_collapsed++;
 out_up_write:
 	up_write(&mm->mmap_sem);
@@ -1992,9 +1988,6 @@
  
 out:
 	mem_cgroup_uncharge_page(new_page);
-#ifdef CONFIG_NUMA
-	put_page(new_page);
-#endif
 	goto out_up_write;
 }
  
@@ -2260,8 +2253,6 @@
 	barrier(); /* write khugepaged_pages_to_scan to local stack */
  
 	while (progress < pages) {
-		cond_resched();
-
 #ifndef CONFIG_NUMA
 		if (!hpage)
 			hpage = khugepaged_alloc_hugepage(&wait);
  
@@ -2274,8 +2265,12 @@
 				break;
 			wait = false;
 			khugepaged_alloc_sleep();
+		} else if (hpage) {
+			put_page(hpage);
+			hpage = NULL;
 		}
 #endif
+		cond_resched();
  
 		if (unlikely(kthread_should_stop() || freezing(current)))
 			break;
...	...	@@ -1873,15 +1873,12 @@
1873	1873	*hpage = ERR_PTR(-ENOMEM);
1874	1874	return;
1875	1875	}
	1876	+ *hpage = new_page;
1876	1877	count_vm_event(THP_COLLAPSE_ALLOC);
1877	1878	#endif
1878	1879
1879		- if (unlikely(mem_cgroup_newpage_charge(new_page, mm, GFP_KERNEL))) {
1880		-#ifdef CONFIG_NUMA
1881		- put_page(new_page);
1882		-#endif
	1880	+ if (unlikely(mem_cgroup_newpage_charge(new_page, mm, GFP_KERNEL)))
1883	1881	return;
1884		- }
1885	1882
1886	1883	/*
1887	1884	* Prevent all access to pagetables with the exception of
1888	1885
...	...	@@ -1982,9 +1979,8 @@
1982	1979	prepare_pmd_huge_pte(pgtable, mm);
1983	1980	spin_unlock(&mm->page_table_lock);
1984	1981
1985		-#ifndef CONFIG_NUMA
1986	1982	*hpage = NULL;
1987		-#endif
	1983	+
1988	1984	khugepaged_pages_collapsed++;
1989	1985	out_up_write:
1990	1986	up_write(&mm->mmap_sem);
...	...	@@ -1992,9 +1988,6 @@
1992	1988
1993	1989	out:
1994	1990	mem_cgroup_uncharge_page(new_page);
1995		-#ifdef CONFIG_NUMA
1996		- put_page(new_page);
1997		-#endif
1998	1991	goto out_up_write;
1999	1992	}
2000	1993
...	...	@@ -2260,8 +2253,6 @@
2260	2253	barrier(); /* write khugepaged_pages_to_scan to local stack */
2261	2254
2262	2255	while (progress < pages) {
2263		- cond_resched();
2264		-
2265	2256	#ifndef CONFIG_NUMA
2266	2257	if (!hpage)
2267	2258	hpage = khugepaged_alloc_hugepage(&wait);
2268	2259
...	...	@@ -2274,8 +2265,12 @@
2274	2265	break;
2275	2266	wait = false;
2276	2267	khugepaged_alloc_sleep();
	2268	+ } else if (hpage) {
	2269	+ put_page(hpage);
	2270	+ hpage = NULL;
2277	2271	}
2278	2272	#endif
	2273	+ cond_resched();
2279	2274
2280	2275	if (unlikely(kthread_should_stop() \|\| freezing(current)))
2281	2276	break;