move defaults to func signature

Author: vpuri3

src/common.jl

@@ -8,8 +8,6 @@ struct LinearCache{TA,Tb,Tu,Tp,Talg,Tc,Tl,Tr,Ttol}
     isfresh::Bool # false => cacheval is set wrt A, true => update cacheval wrt A
     Pl::Tl        # store final preconditioner here. not being used rn
     Pr::Tr        # wrappers are using preconditioner in cache.alg for now
-
-    # common arguments
     abstol::Ttol
     reltol::Ttol
     maxiters::Int
@@ -52,7 +50,10 @@ SciMLBase.init(prob::LinearProblem, args...; kwargs...) = SciMLBase.init(prob,no
 
 function SciMLBase.init(prob::LinearProblem, alg::Union{SciMLLinearSolveAlgorithm,Nothing}, args...;
                         alias_A = false, alias_b = false,
-                        abstol=0, reltol=0, maxiters=0, verbose=false,
+                        abstol=√eps(eltype(prob.A)),
+                        reltol=√eps(eltype(prob.A)),
+                        maxiters=length(prob.b),
+                        verbose=false,
                         kwargs...,
                        )
     @unpack A, b, u0, p = prob
@@ -69,11 +70,6 @@ function SciMLBase.init(prob::LinearProblem, alg::Union{SciMLLinearSolveAlgorith
     A = alias_A ? A : deepcopy(A)
     b = alias_b ? b : deepcopy(b)
 
-
-    abstol   = (abstol   == 0) ? √eps(eltype(A)) : abstol
-    reltol   = (reltol   == 0) ? √eps(eltype(A)) : reltol
-    maxiters = (maxiters == 0) ? length(b)       : maxiters
-
     cache = LinearCache{
         typeof(A),
         typeof(b),
@@ -84,7 +80,6 @@ function SciMLBase.init(prob::LinearProblem, alg::Union{SciMLLinearSolveAlgorith
         typeof(Pl),
         typeof(Pr),
         typeof(reltol),
-        typeof(maxiters)
     }(
         A,
         b,