osd: cast `whoami` to unsigned so it can be used as the seed for RNG

default_random_engine's result_type is `unsigned int`, so we need to
pass an `unsigned int` as its seed.

Fixes: http://tracker.ceph.com/issues/26890
Signed-off-by: Kefu Chai <kchai@redhat.com>
Conflicts:
	src/osd/OSD.cc: this breaks the build with clang. and in master
we are not using std::default_random_engine for setting the scrub
interval. so this change is not cherry-picked from master.

diff --git a/src/osd/OSD.cc b/src/osd/OSD.cc
index 042097bb35e224710c9ad7185321545a61d04e8c..e2d1a6db7a5e7a0c2fd7cef40cc2457edd88cf40 100644 (file)
--- a/src/osd/OSD.cc
+++ b/src/osd/OSD.cc
@@ -2055,7 +2055,7 @@ double OSD::get_tick_interval() const
 {
   // vary +/- 5% to avoid scrub scheduling livelocks
   constexpr auto delta = 0.05;
-  std::default_random_engine rng{whoami};
+  std::default_random_engine rng{static_cast<unsigned>(whoami)};
   return (OSD_TICK_INTERVAL *
           std::uniform_real_distribution<>{1.0 - delta, 1.0 + delta}(rng));
 }