add GPU construction test

Author: vchuravy

examples/p4est_2d_dgsem/elixir_advection_basic_gpu.jl

@@ -0,0 +1,60 @@
+# The same setup as tree_2d_dgsem/elixir_advection_basic.jl
+# to verify the StructuredMesh implementation against TreeMesh
+
+using OrdinaryDiffEqSSPRK, OrdinaryDiffEqLowStorageRK
+using Trixi
+
+###############################################################################
+# semidiscretization of the linear advection equation
+
+advection_velocity = (0.2, -0.7)
+equations = LinearScalarAdvectionEquation2D(advection_velocity)
+
+# Create DG solver with polynomial degree = 3 and (local) Lax-Friedrichs/Rusanov flux as surface flux
+solver = DGSEM(polydeg = 3, surface_flux = flux_lax_friedrichs)
+
+coordinates_min = (-1.0, -1.0) # minimum coordinates (min(x), min(y))
+coordinates_max = (1.0, 1.0) # maximum coordinates (max(x), max(y))
+
+trees_per_dimension = (8, 8)
+
+# Create P4estMesh with 8 x 8 trees and 16 x 16 elements
+mesh = P4estMesh(trees_per_dimension, polydeg = 3,
+                 coordinates_min = coordinates_min, coordinates_max = coordinates_max,
+                 initial_refinement_level = 1)
+
+# A semidiscretization collects data structures and functions for the spatial discretization
+semi = SemidiscretizationHyperbolic(mesh, equations, initial_condition_convergence_test,
+                                    solver)
+
+###############################################################################
+# ODE solvers, callbacks etc.
+
+# Create ODE problem with time span from 0.0 to 1.0
+ode = semidiscretize(semi, (0.0, 1.0); real_type = nothing, storage_type = nothing)
+
+# At the beginning of the main loop, the SummaryCallback prints a summary of the simulation setup
+# and resets the timers
+summary_callback = SummaryCallback()
+
+# The AnalysisCallback allows to analyse the solution in regular intervals and prints the results
+analysis_callback = AnalysisCallback(semi, interval = 100)
+
+# The SaveSolutionCallback allows to save the solution to a file in regular intervals
+save_solution = SaveSolutionCallback(interval = 100,
+                                     solution_variables = cons2prim)
+
+# The StepsizeCallback handles the re-calculation of the maximum Δt after each time step
+stepsize_callback = StepsizeCallback(cfl = 1.6)
+
+# Create a CallbackSet to collect all callbacks such that they can be passed to the ODE solver
+callbacks = CallbackSet(summary_callback, analysis_callback, save_solution,
+                        stepsize_callback)
+
+###############################################################################
+# run the simulation
+
+# # OrdinaryDiffEq's `solve` method evolves the solution in time and executes the passed callbacks
+# sol = solve(ode, CarpenterKennedy2N54(williamson_condition = false);
+#             dt = 1.0, # solve needs some value here but it will be overwritten by the stepsize_callback
+#             ode_default_options()..., callback = callbacks);

test/test_cuda.jl

@@ -12,7 +12,29 @@ include("test_trixi.jl")
 outdir = "out"
 isdir(outdir) && rm(outdir, recursive = true)
 
-# TODO:
+EXAMPLES_DIR = joinpath(examples_dir(), "p4est_2d_dgsem")
+
+@trixi_testset "elixir_advection_basic.jl (Float32)" begin
+    @test_trixi_include(joinpath(EXAMPLES_DIR, "elixir_advection_basic.jl"),
+                        # Expected errors are exactly the same as with TreeMesh!
+                        l2=[8.311947673061856e-6],
+                        linf=[6.627000273229378e-5],
+                        real_type=Float32,
+                        storage_type=CuArray)
+    # # Ensure that we do not have excessive memory allocations
+    # # (e.g., from type instabilities)
+    # let
+    #     t = sol.t[end]
+    #     u_ode = sol.u[end]
+    #     du_ode = similar(u_ode)
+    #     @test (@allocated Trixi.rhs!(du_ode, u_ode, semi, t)) < 1000
+    # end
+    @test real(ode.p.solver) == Float32
+    @test real(ode.p.solver.basis) == Float32
+    @test real(ode.p.solver.mortar) == Float32
+    # TODO: remake ignores the mesh itself as well
+    @test real(ode.p.mesh) == Float64
+end
 
 # Clean up afterwards: delete Trixi.jl output directory
 @test_nowarn isdir(outdir) && rm(outdir, recursive = true)