Fix stepWork.useGpuXHalo on search steps

The value of stepWork.useGpuXHalo was not correct on search steps when
mdrun always falls back to comunicating over the CPU.

diff --git a/src/gromacs/mdlib/sim_util.cpp b/src/gromacs/mdlib/sim_util.cpp
index 3882768ada0e9dcb72ec7ed6284fdaacc3bfbb0b..13a13d23eac9f6b8921ee152fcbc57e162c148f5 100644 (file)
--- a/src/gromacs/mdlib/sim_util.cpp
+++ b/src/gromacs/mdlib/sim_util.cpp
@@ -987,7 +987,7 @@ static StepWorkload setupStepWorkload(const int                     legacyFlags,
     const bool rankHasGpuPmeTask = simulationWork.useGpuPme && !simulationWork.haveSeparatePmeRank;
     flags.useGpuPmeFReduction    = flags.computeSlowForces && flags.useGpuFBufferOps
                                 && (rankHasGpuPmeTask || simulationWork.useGpuPmePpCommunication);
-    flags.useGpuXHalo          = simulationWork.useGpuHaloExchange;
+    flags.useGpuXHalo          = simulationWork.useGpuHaloExchange && !flags.doNeighborSearch;
     flags.useGpuFHalo          = simulationWork.useGpuHaloExchange && flags.useGpuFBufferOps;
     flags.haveGpuPmeOnThisRank = rankHasGpuPmeTask && flags.computeSlowForces;
     flags.combineMtsForcesBeforeHaloExchange =