mm: no need to check return value of debugfs_create functions

When calling debugfs functions, there is no need to ever check the
return value.  The function can work or not, but the code logic should
never do something different based on this.

Link: http://lkml.kernel.org/r/20190122152151.16139-14-gregkh@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: David Rientjes <rientjes@google.com>
Cc: Laura Abbott <labbott@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

mm/cma_debug.c

@@ -191,8 +191,6 @@ static int __init cma_debugfs_init(void)
 	int i;
 
 	cma_debugfs_root = debugfs_create_dir("cma", NULL);
-	if (!cma_debugfs_root)
-		return -ENOMEM;
 
 	for (i = 0; i < cma_area_count; i++)
 		cma_debugfs_add_one(&cma_areas[i], i);

mm/failslab.c

@@ -48,18 +48,12 @@ static int __init failslab_debugfs_init(void)
 	if (IS_ERR(dir))
 		return PTR_ERR(dir);
 
-	if (!debugfs_create_bool("ignore-gfp-wait", mode, dir,
-				&failslab.ignore_gfp_reclaim))
-		goto fail;
-	if (!debugfs_create_bool("cache-filter", mode, dir,
-				&failslab.cache_filter))
-		goto fail;
+	debugfs_create_bool("ignore-gfp-wait", mode, dir,
+			    &failslab.ignore_gfp_reclaim);
+	debugfs_create_bool("cache-filter", mode, dir,
+			    &failslab.cache_filter);
 
 	return 0;
-fail:
-	debugfs_remove_recursive(dir);
-
-	return -ENOMEM;
 }
 
 late_initcall(failslab_debugfs_init);

mm/gup_benchmark.c

@@ -122,12 +122,8 @@ static const struct file_operations gup_benchmark_fops = {
 
 static int gup_benchmark_init(void)
 {
-	void *ret;
-
-	ret = debugfs_create_file_unsafe("gup_benchmark", 0600, NULL, NULL,
-			&gup_benchmark_fops);
-	if (!ret)
-		pr_warn("Failed to create gup_benchmark in debugfs");
+	debugfs_create_file_unsafe("gup_benchmark", 0600, NULL, NULL,
+				   &gup_benchmark_fops);
 
 	return 0;
 }

mm/huge_memory.c

@@ -2887,12 +2887,8 @@ DEFINE_SIMPLE_ATTRIBUTE(split_huge_pages_fops, NULL, split_huge_pages_set,
 
 static int __init split_huge_pages_debugfs(void)
 {
-	void *ret;
-
-	ret = debugfs_create_file("split_huge_pages", 0200, NULL, NULL,
-			&split_huge_pages_fops);
-	if (!ret)
-		pr_warn("Failed to create split_huge_pages in debugfs");
+	debugfs_create_file("split_huge_pages", 0200, NULL, NULL,
+			    &split_huge_pages_fops);
 	return 0;
 }
 late_initcall(split_huge_pages_debugfs);

mm/memblock.c

@@ -2005,8 +2005,7 @@ DEFINE_SHOW_ATTRIBUTE(memblock_debug);
 static int __init memblock_init_debugfs(void)
 {
 	struct dentry *root = debugfs_create_dir("memblock", NULL);
-	if (!root)
-		return -ENXIO;
+
 	debugfs_create_file("memory", 0444, root,
 			    &memblock.memory, &memblock_debug_fops);
 	debugfs_create_file("reserved", 0444, root,

mm/memory.c

@@ -3334,12 +3334,8 @@ DEFINE_DEBUGFS_ATTRIBUTE(fault_around_bytes_fops,
 
 static int __init fault_around_debugfs(void)
 {
-	void *ret;
-
-	ret = debugfs_create_file_unsafe("fault_around_bytes", 0644, NULL, NULL,
-			&fault_around_bytes_fops);
-	if (!ret)
-		pr_warn("Failed to create fault_around_bytes in debugfs");
+	debugfs_create_file_unsafe("fault_around_bytes", 0644, NULL, NULL,
+				   &fault_around_bytes_fops);
 	return 0;
 }
 late_initcall(fault_around_debugfs);

mm/page_alloc.c

@@ -3230,24 +3230,14 @@ static int __init fail_page_alloc_debugfs(void)
 
 	dir = fault_create_debugfs_attr("fail_page_alloc", NULL,
 					&fail_page_alloc.attr);
-	if (IS_ERR(dir))
-		return PTR_ERR(dir);
 
-	if (!debugfs_create_bool("ignore-gfp-wait", mode, dir,
-				&fail_page_alloc.ignore_gfp_reclaim))
-		goto fail;
-	if (!debugfs_create_bool("ignore-gfp-highmem", mode, dir,
-				&fail_page_alloc.ignore_gfp_highmem))
-		goto fail;
-	if (!debugfs_create_u32("min-order", mode, dir,
-				&fail_page_alloc.min_order))
-		goto fail;
+	debugfs_create_bool("ignore-gfp-wait", mode, dir,
+			    &fail_page_alloc.ignore_gfp_reclaim);
+	debugfs_create_bool("ignore-gfp-highmem", mode, dir,
+			    &fail_page_alloc.ignore_gfp_highmem);
+	debugfs_create_u32("min-order", mode, dir, &fail_page_alloc.min_order);
 
 	return 0;
-fail:
-	debugfs_remove_recursive(dir);
-
-	return -ENOMEM;
 }
 
 late_initcall(fail_page_alloc_debugfs);

mm/page_owner.c

@@ -625,16 +625,14 @@ static const struct file_operations proc_page_owner_operations = {
 
 static int __init pageowner_init(void)
 {
-	struct dentry *dentry;
-
 	if (!static_branch_unlikely(&page_owner_inited)) {
 		pr_info("page_owner is disabled\n");
 		return 0;
 	}
 
-	dentry = debugfs_create_file("page_owner", 0400, NULL,
-				     NULL, &proc_page_owner_operations);
+	debugfs_create_file("page_owner", 0400, NULL, NULL,
+			    &proc_page_owner_operations);
 
-	return PTR_ERR_OR_ZERO(dentry);
+	return 0;
 }
 late_initcall(pageowner_init)

mm/vmstat.c

@@ -2121,21 +2121,14 @@ static int __init extfrag_debug_init(void)
 	struct dentry *extfrag_debug_root;
 
 	extfrag_debug_root = debugfs_create_dir("extfrag", NULL);
-	if (!extfrag_debug_root)
-		return -ENOMEM;
 
-	if (!debugfs_create_file("unusable_index", 0444,
-			extfrag_debug_root, NULL, &unusable_file_ops))
-		goto fail;
+	debugfs_create_file("unusable_index", 0444, extfrag_debug_root, NULL,
+			    &unusable_file_ops);
 
-	if (!debugfs_create_file("extfrag_index", 0444,
-			extfrag_debug_root, NULL, &extfrag_file_ops))
-		goto fail;
+	debugfs_create_file("extfrag_index", 0444, extfrag_debug_root, NULL,
+			    &extfrag_file_ops);
 
 	return 0;
-fail:
-	debugfs_remove_recursive(extfrag_debug_root);
-	return -ENOMEM;
 }
 
 module_init(extfrag_debug_init);