Remove some of the false positives when sorting by utilizing the MAP_SHARED bit.
This helps deal with the COW cases where a virtual address is modified but is mapped to a read-only shared library area because the perf tool doesn't understand COW faults. Using the MAP_SHARED bit tells the tool in this example the memory is private and will not cause contention with other processes accessing the same shared library area. Signed-off-by: Don Zickus <[email protected]> --- tools/perf/util/sort.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/tools/perf/util/sort.c b/tools/perf/util/sort.c index e016fc1..be675f4 100644 --- a/tools/perf/util/sort.c +++ b/tools/perf/util/sort.c @@ -1,3 +1,4 @@ +#include <sys/mman.h> #include "sort.h" #include "hist.h" #include "comm.h" @@ -1001,7 +1002,8 @@ sort__physid_daddr_cmp(struct hist_entry *left, struct hist_entry *right) * assumed to be unity mapped. Sort those on address then pid. */ - if (l_map->maj || l_map->min || l_map->ino || l_map->ino_generation) { + if ((l_map->flags & MAP_SHARED) && + (l_map->maj || l_map->min || l_map->ino || l_map->ino_generation)) { /* mmapped areas */ if (l_map->maj > r_map->maj) return -1; -- 1.7.11.7 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
