summaryrefslogtreecommitdiff
path: root/mm/internal.h
diff options
context:
space:
mode:
authorVlastimil Babka <vbabka@suse.cz>2016-03-15 14:55:56 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2016-03-15 16:55:16 -0700
commitedf14cdbf9a0e5ab52698ca66d07a76ade0d5c46 (patch)
tree347fa732387b755a485c2d29e50485529e077b8d /mm/internal.h
parent420adbe9fc1a45187cfa74df9dbfd72272c4e2fa (diff)
downloadlwn-edf14cdbf9a0e5ab52698ca66d07a76ade0d5c46.tar.gz
lwn-edf14cdbf9a0e5ab52698ca66d07a76ade0d5c46.zip
mm, printk: introduce new format string for flags
In mm we use several kinds of flags bitfields that are sometimes printed for debugging purposes, or exported to userspace via sysfs. To make them easier to interpret independently on kernel version and config, we want to dump also the symbolic flag names. So far this has been done with repeated calls to pr_cont(), which is unreliable on SMP, and not usable for e.g. sysfs export. To get a more reliable and universal solution, this patch extends printk() format string for pointers to handle the page flags (%pGp), gfp_flags (%pGg) and vma flags (%pGv). Existing users of dump_flag_names() are converted and simplified. It would be possible to pass flags by value instead of pointer, but the %p format string for pointers already has extensions for various kernel structures, so it's a good fit, and the extra indirection in a non-critical path is negligible. [linux@rasmusvillemoes.dk: lots of good implementation suggestions] Signed-off-by: Vlastimil Babka <vbabka@suse.cz> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Arnaldo Carvalho de Melo <acme@kernel.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Minchan Kim <minchan@kernel.org> Cc: Sasha Levin <sasha.levin@oracle.com> Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com> Cc: Mel Gorman <mgorman@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'mm/internal.h')
-rw-r--r--mm/internal.h6
1 files changed, 6 insertions, 0 deletions
diff --git a/mm/internal.h b/mm/internal.h
index a38a21ebddb4..6636e1d3ecf0 100644
--- a/mm/internal.h
+++ b/mm/internal.h
@@ -14,6 +14,7 @@
#include <linux/fs.h>
#include <linux/mm.h>
#include <linux/pagemap.h>
+#include <linux/tracepoint-defs.h>
/*
* The set of flags that only affect watermark checking and reclaim
@@ -466,4 +467,9 @@ static inline void try_to_unmap_flush_dirty(void)
}
#endif /* CONFIG_ARCH_WANT_BATCHED_UNMAP_TLB_FLUSH */
+
+extern const struct trace_print_flags pageflag_names[];
+extern const struct trace_print_flags vmaflag_names[];
+extern const struct trace_print_flags gfpflag_names[];
+
#endif /* __MM_INTERNAL_H */