mm: fix page_owner initializing issue for arm32

Page owner of pages used by page owner itself used is missing on arm32
targets.  The reason is dummy_handle and failure_handle is not initialized
correctly.  Buddy allocator is used to initialize these two handles.
However, buddy allocator is not ready when page owner calls it.  This
change fixed that by initializing page owner after buddy initialization.

The working flow before and after this change are:
original logic:
 1. allocated memory for page_ext(using memblock).
 2. invoke the init callback of page_ext_ops like page_owner(using buddy
    allocator).
 3. initialize buddy.

after this change:
 1. allocated memory for page_ext(using memblock).
 2. initialize buddy.
 3. invoke the init callback of page_ext_ops like page_owner(using buddy
    allocator).

with the change, failure/dummy_handle can get its correct value and page
owner output for example has the one for page owner itself:

  Page allocated via order 2, mask 0x6202c0(GFP_USER|__GFP_NOWARN), pid 1006, ts 67278156558 ns
  PFN 543776 type Unmovable Block 531 type Unmovable Flags 0x0()
    init_page_owner+0x28/0x2f8
    invoke_init_callbacks_flatmem+0x24/0x34
    start_kernel+0x33c/0x5d8

Link: https://lkml.kernel.org/r/1603104925-5888-1-git-send-email-zhenhuah@codeaurora.org
Signed-off-by: Zhenhua Huang <zhenhuah@codeaurora.org>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/include/linux/page_ext.h b/include/linux/page_ext.h
index cfce186f0c4e0ecd8be7c211e8a3fbb95c963242..aff81ba31bd8bdbe845cb2852aebffdea66c1bbb 100644 (file)
--- a/include/linux/page_ext.h
+++ b/include/linux/page_ext.h
@@ -44,8 +44,12 @@ static inline void page_ext_init_flatmem(void)
 {
 }
 extern void page_ext_init(void);
+static inline void page_ext_init_flatmem_late(void)
+{
+}
 #else
 extern void page_ext_init_flatmem(void);
+extern void page_ext_init_flatmem_late(void);
 static inline void page_ext_init(void)
 {
 }
@@ -76,6 +80,10 @@ static inline void page_ext_init(void)
 {
 }
 
+static inline void page_ext_init_flatmem_late(void)
+{
+}
+
 static inline void page_ext_init_flatmem(void)
 {
 }

diff --git a/init/main.c b/init/main.c
index 32b2a8affafd1b434ec319a1bfb842e7ac7a298f..82ae0d1345a0a547402e15b91624446ee76b283a 100644 (file)
--- a/init/main.c
+++ b/init/main.c
@@ -828,6 +828,8 @@ static void __init mm_init(void)
        init_debug_pagealloc();
        report_meminit();
        mem_init();
+       /* page_owner must be initialized after buddy is ready */
+       page_ext_init_flatmem_late();
        kmem_cache_init();
        kmemleak_init();
        pgtable_init();

diff --git a/mm/page_ext.c b/mm/page_ext.c
index a3616f7a0e9e923c2add3a8459c8b2a82da524f7..16b161f28a31d974bc7651c5ae4a0af9ee6b9637 100644 (file)
--- a/mm/page_ext.c
+++ b/mm/page_ext.c
@@ -99,12 +99,19 @@ static void __init invoke_init_callbacks(void)
        }
 }
 
+#ifndef CONFIG_SPARSEMEM
+void __init page_ext_init_flatmem_late(void)
+{
+       invoke_init_callbacks();
+}
+#endif
+
 static inline struct page_ext *get_entry(void *base, unsigned long index)
 {
        return base + page_ext_size * index;
 }
 
-#if !defined(CONFIG_SPARSEMEM)
+#ifndef CONFIG_SPARSEMEM
 
 
 void __meminit pgdat_page_ext_init(struct pglist_data *pgdat)
@@ -177,7 +184,6 @@ void __init page_ext_init_flatmem(void)
                        goto fail;
        }
        pr_info("allocated %ld bytes of page_ext\n", total_usage);
-       invoke_init_callbacks();
        return;
 
 fail: