CCS/TMS320F28027F: mainISR running from FLASH

Part Number:TMS320F28027F

Tool/software: Code Composer Studio

HI,

I'm wondering can we run the mainISR from flash without copying the code into RAM?  Will there be any affection on the motor control ? 

Most of the motorware project example copy mainISR into RAM like the following. Can we get rid of it? Any affection ?

#ifdef FLASH
#pragma CODE_SECTION(mainISR,"ramfuncs");
#endif

In general, the RAM is faster than the FLASH, but since there's very limited RAM memory size, i'm trying to refactor the code and save as much memory as we can.