[PATCH 1/2 v2] makedumpfile: Add a default action to exclude hwpoison page from vmcore

[Mitsuhiro Tanino]

This patch introduces a function which excludes hwpoison pages
from vmcore as a default action for makedumpfile.

Signed-off-by: Mitsuhiro Tanino <mitsuhiro.tanino.gm at hitachi.com>
diff -uprN a/makedumpfile.c b/makedumpfile.c
--- a/makedumpfile.c	2012-10-01 15:26:54.510354074 +0900
+++ b/makedumpfile.c	2012-10-29 22:32:24.913057535 +0900
@@ -43,6 +43,7 @@ unsigned long long pfn_cache;
 unsigned long long pfn_cache_private;
 unsigned long long pfn_user;
 unsigned long long pfn_free;
+unsigned long long pfn_hwpoison;
 
 unsigned long long num_dumped;
 
@@ -969,6 +970,7 @@ get_structure_info(void)
 	ENUM_NUMBER_INIT(PG_lru, "PG_lru");
 	ENUM_NUMBER_INIT(PG_private, "PG_private");
 	ENUM_NUMBER_INIT(PG_swapcache, "PG_swapcache");
+	ENUM_NUMBER_INIT(PG_hwpoison, "PG_hwpoison");
 
 	TYPEDEF_SIZE_INIT(nodemask_t, "nodemask_t");
 
@@ -1371,6 +1373,7 @@ write_vmcoreinfo_data(void)
 	WRITE_NUMBER("PG_lru", PG_lru);
 	WRITE_NUMBER("PG_private", PG_private);
 	WRITE_NUMBER("PG_swapcache", PG_swapcache);
+	WRITE_NUMBER("PG_hwpoison", PG_hwpoison);
 
 	/*
 	 * write the source file of 1st kernel
@@ -1659,6 +1662,7 @@ read_vmcoreinfo(void)
 	READ_NUMBER("PG_lru", PG_lru);
 	READ_NUMBER("PG_private", PG_private);
 	READ_NUMBER("PG_swapcache", PG_swapcache);
+	READ_NUMBER("PG_hwpoison", PG_hwpoison);
 
 	READ_SRCFILE("pud_t", pud_t);
 
@@ -3856,6 +3860,13 @@ __exclude_unnecessary_pages(unsigned lon
 			if (clear_bit_on_2nd_bitmap_for_kernel(pfn))
 				pfn_user++;
 		}
+		/*
+		 * Exclude the hwpoison page.
+		 */
+		else if (isHWPOISON(flags)) {
+			clear_bit_on_2nd_bitmap_for_kernel(pfn);
+			pfn_hwpoison++;
+		}
 	}
 	return TRUE;
 }
@@ -3914,11 +3925,13 @@ exclude_unnecessary_pages_cyclic(void)
 			return FALSE;
 
 	/*
-	 * Exclude cache pages, cache private pages, user data pages, and free pages.
+	 * Exclude cache pages, cache private pages, user data pages,
+	   free pages and hwpoison pages.
 	 */
 	if (info->dump_level & DL_EXCLUDE_CACHE ||
 	    info->dump_level & DL_EXCLUDE_CACHE_PRI ||
-	    info->dump_level & DL_EXCLUDE_USER_DATA) {
+	    info->dump_level & DL_EXCLUDE_USER_DATA ||
+	    (NUMBER(PG_hwpoison) != NOT_FOUND_NUMBER)) {
 
 		gettimeofday(&tv_start, NULL);
 
@@ -4018,11 +4031,13 @@ create_2nd_bitmap(void)
 	}
 
 	/*
-	 * Exclude cache pages, cache private pages, user data pages.
+	 * Exclude cache pages, cache private pages, user data pages,
+	 * and hwpoison pages.
 	 */
 	if (info->dump_level & DL_EXCLUDE_CACHE ||
 	    info->dump_level & DL_EXCLUDE_CACHE_PRI ||
-	    info->dump_level & DL_EXCLUDE_USER_DATA) {
+	    info->dump_level & DL_EXCLUDE_USER_DATA ||
+	    (NUMBER(PG_hwpoison) != NOT_FOUND_NUMBER)) {
 		if (!exclude_unnecessary_pages()) {
 			ERRMSG("Can't exclude unnecessary pages.\n");
 			return FALSE;
@@ -5062,7 +5077,8 @@ write_elf_pages_cyclic(struct cache_data
 	/*
 	 * Reset counter for debug message.
 	 */
-	pfn_zero =  pfn_cache = pfn_cache_private = pfn_user = pfn_free = 0;
+	pfn_zero = pfn_cache = pfn_cache_private = 0;
+	pfn_user = pfn_free = pfn_hwpoison = 0;
 	pfn_memhole = info->max_mapnr;
 
 	info->cyclic_start_pfn = 0;
@@ -5902,7 +5918,8 @@ write_kdump_pages_and_bitmap_cyclic(stru
 	/*
 	 * Reset counter for debug message.
 	 */
-	pfn_zero =  pfn_cache = pfn_cache_private = pfn_user = pfn_free = 0;
+	pfn_zero = pfn_cache = pfn_cache_private = 0;
+	pfn_user = pfn_free = pfn_hwpoison = 0;
 	pfn_memhole = info->max_mapnr;
 
 	cd_header->offset
@@ -6687,7 +6704,7 @@ print_report(void)
 	pfn_original = info->max_mapnr - pfn_memhole;
 
 	pfn_excluded = pfn_zero + pfn_cache + pfn_cache_private
-	    + pfn_user + pfn_free;
+	    + pfn_user + pfn_free + pfn_hwpoison;
 	shrinking = (pfn_original - pfn_excluded) * 100;
 	shrinking = shrinking / pfn_original;
 
@@ -6700,6 +6717,7 @@ print_report(void)
 	    pfn_cache_private);
 	REPORT_MSG("    User process data pages : 0x%016llx\n", pfn_user);
 	REPORT_MSG("    Free pages              : 0x%016llx\n", pfn_free);
+	REPORT_MSG("    Hwpoison pages          : 0x%016llx\n", pfn_hwpoison);
 	REPORT_MSG("  Remaining pages  : 0x%016llx\n",
 	    pfn_original - pfn_excluded);
 	REPORT_MSG("  (The number of pages is reduced to %lld%%.)\n",
diff -uprN a/makedumpfile.h b/makedumpfile.h
--- a/makedumpfile.h	2012-10-01 15:26:54.512354076 +0900
+++ b/makedumpfile.h	2012-10-29 20:59:19.723015190 +0900
@@ -107,6 +107,8 @@ test_bit(int nr, unsigned long addr)
 #define isLRU(flags)		test_bit(NUMBER(PG_lru), flags)
 #define isPrivate(flags)	test_bit(NUMBER(PG_private), flags)
 #define isSwapCache(flags)	test_bit(NUMBER(PG_swapcache), flags)
+#define isHWPOISON(flags)	(test_bit(NUMBER(PG_hwpoison), flags) \
+				&& (NUMBER(PG_hwpoison) != NOT_FOUND_NUMBER))
 
 static inline int
 isAnon(unsigned long mapping)
@@ -1244,6 +1246,7 @@ struct number_table {
 	long	PG_lru;
 	long	PG_private;
 	long	PG_swapcache;
+	long    PG_hwpoison;
 };
 
 struct srcfile_table {