mm: introduce helper function mem_init_print_info() to simplify mem_init()

Introduce helper function mem_init_print_info() to simplify mem_init()
across different architectures, which also unifies the format and
information printed.

Function mem_init_print_info() calculates memory statistics information
without walking each page, so it should be a little faster on some
architectures.

Also introduce another helper get_num_physpages() to kill the global
variable num_physpages.

Signed-off-by: Jiang Liu <jiang.liu@huawei.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Michel Lespinasse <walken@google.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

diff --git a/include/linux/mm.h b/include/linux/mm.h
index 4310f80ce956ba5a1f245214df33d34d17449267..09c235301dbb153d5395f4d3df44c2218432fab3 100644 (file)
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -1323,6 +1323,7 @@ extern void free_highmem_page(struct page *page);
 #endif
 
 extern void adjust_managed_page_count(struct page *page, long count);
+extern void mem_init_print_info(const char *str);
 
 /* Free the reserved page into the buddy system, so it gets managed. */
 static inline void __free_reserved_page(struct page *page)
@@ -1358,6 +1359,17 @@ static inline unsigned long free_initmem_default(int poison)
                                  poison, "unused kernel");
 }
 
+static inline unsigned long get_num_physpages(void)
+{
+       int nid;
+       unsigned long phys_pages = 0;
+
+       for_each_online_node(nid)
+               phys_pages += node_present_pages(nid);
+
+       return phys_pages;
+}
+
 #ifdef CONFIG_HAVE_MEMBLOCK_NODE_MAP
 /*
  * With CONFIG_HAVE_MEMBLOCK_NODE_MAP set, an architecture may initialise its

diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index d9445c4f5fd7e06192c60a5cc18ccb9f714ff83f..327516b7aee96de1caf2afebb048955734a71ebd 100644 (file)
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -61,6 +61,7 @@
 #include <linux/hugetlb.h>
 #include <linux/sched/rt.h>
 
+#include <asm/sections.h>
 #include <asm/tlbflush.h>
 #include <asm/div64.h>
 #include "internal.h"
@@ -5246,6 +5247,57 @@ void free_highmem_page(struct page *page)
 }
 #endif
 
+
+void __init mem_init_print_info(const char *str)
+{
+       unsigned long physpages, codesize, datasize, rosize, bss_size;
+       unsigned long init_code_size, init_data_size;
+
+       physpages = get_num_physpages();
+       codesize = _etext - _stext;
+       datasize = _edata - _sdata;
+       rosize = __end_rodata - __start_rodata;
+       bss_size = __bss_stop - __bss_start;
+       init_data_size = __init_end - __init_begin;
+       init_code_size = _einittext - _sinittext;
+
+       /*
+        * Detect special cases and adjust section sizes accordingly:
+        * 1) .init.* may be embedded into .data sections
+        * 2) .init.text.* may be out of [__init_begin, __init_end],
+        *    please refer to arch/tile/kernel/vmlinux.lds.S.
+        * 3) .rodata.* may be embedded into .text or .data sections.
+        */
+#define adj_init_size(start, end, size, pos, adj) \
+       if (start <= pos && pos < end && size > adj) \
+               size -= adj;
+
+       adj_init_size(__init_begin, __init_end, init_data_size,
+                    _sinittext, init_code_size);
+       adj_init_size(_stext, _etext, codesize, _sinittext, init_code_size);
+       adj_init_size(_sdata, _edata, datasize, __init_begin, init_data_size);
+       adj_init_size(_stext, _etext, codesize, __start_rodata, rosize);
+       adj_init_size(_sdata, _edata, datasize, __start_rodata, rosize);
+
+#undef adj_init_size
+
+       printk("Memory: %luK/%luK available "
+              "(%luK kernel code, %luK rwdata, %luK rodata, "
+              "%luK init, %luK bss, %luK reserved"
+#ifdef CONFIG_HIGHMEM
+              ", %luK highmem"
+#endif
+              "%s%s)\n",
+              nr_free_pages() << (PAGE_SHIFT-10), physpages << (PAGE_SHIFT-10),
+              codesize >> 10, datasize >> 10, rosize >> 10,
+              (init_data_size + init_code_size) >> 10, bss_size >> 10,
+              (physpages - totalram_pages) << (PAGE_SHIFT-10),
+#ifdef CONFIG_HIGHMEM
+              totalhigh_pages << (PAGE_SHIFT-10),
+#endif
+              str ? ", " : "", str ? str : "");
+}
+
 /**
  * set_dma_reserve - set the specified number of pages reserved in the first zone
  * @new_dma_reserve: The number of pages to mark reserved