In file semantic-kernel/dotnet/src/SemanticKernel.Abstractions/Functions/KernelFunction.cs when create logger, add a prefix to the name of the Logger for logging filtering.

line 160 and line 303.

make ILogger logger = kernel.LoggerFactory.CreateLogger(this.Name) ?? NullLogger.Instance;
to ILogger logger = kernel.LoggerFactory.CreateLogger("Microsoft.SemanticKernel.KernelFunction." + this.Name) ?? NullLogger.Instance;

So we can easy to filter logging via config

{
    "Logging": {
        "LogLevel": {
            "Microsoft.SemanticKernel.KernelFunction": "Warning"
        }
    }
}