I've never used the "CodeBlocks IDE" so I only speculate.
The IPP library is independent of the IDE you choose to host your development tools. You will need to configure your makefiles or build scripts to reference the appropriate directories and files in ways similar to using any other IDE or makefiles on Linux. Additionally, the IPP library is precompiled and provided in binary format, so the specific compiler/linker you use with CodeBlocks is not important (e.g., Intel or gcc).
The raw performance of your system is independent of the operating system and the execution mode (kernel mode versus user mode). When you execute an IPP function it will run at the same speed on a Linux system as it will on a Windows system (assuming identical hardware). The differences in performance between operating systems will depend more on the type and frequency of OS calls your application makes, how the OS prioritizes and schedules kernel and user threads, and how drivers and interrupt handlers interact with the hardware and the operating system.
Real-time performance is a combination of having a hardware system that is "fast enough" to handle processing of events (the raw performance of your system) and the ability of the OS to prioritize and insure events and threads are scheduled in a time-critical manner to insure that "real-time" events are handled at the right time. IPP provides your application with a raw performance boost, your operating system and application plus the hardware determine the overall real-time nature.