[PATCH v2] makedumpfile: Add description of pages lost by ENOSPACE in IMPLEMENTATION
zhouwj-fnst at cn.fujitsu.com
Mon Jul 6 17:59:31 PDT 2015
Currently, there is no obvious description in IMPLEMENTATION for
distinguishing the lost pages resulted by ENOSPACE errors or others.
So, it is added.
Signed-off-by: Zhou Wenjian <zhouwj-fnst at cn.fujitsu.com>
IMPLEMENTATION | 4 ++++
1 files changed, 4 insertions(+), 0 deletions(-)
diff --git a/IMPLEMENTATION b/IMPLEMENTATION
index 72df5d5..589c5bf 100644
@@ -240,6 +240,10 @@
The page header and page data are written in pairs. When writing page data
(pfn N+1), if ENOSPACE error happens, the page headers after N won't be
+ Since the data lost is filled with zero when it is read, the page_desc->offset
+ will also be zero. And zero page has its own offset not equal 0. So when reading
+ page from incomplete core, only the page lost by ENOSPACE errors has 0 in its
+ corresponding page descriptor's member offset.
If there is no page data dumped into the DUMPFILE, the DUMPFILE can't be
analysed by crash.
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