Use unlikely() to error checking conditions

[razvand]

Feature request summary

The unlikely() macro is not used consistently to check for unlikely error situations. For example, unlikely() is not being used in lib/ukcpio/cpio.c.

[pranjalrai4]

Hi! I am a Computer Science student at the University of Texas at Austin. I am currently taking virtualization (CS 360v) and I would like to contribute to this project. I saw this issue opened up last year and I would like to work on it, but I was wondering if it was still open.

[razvand]

Sure, @pranjalrai4 , go for it.

[pranjalrai4]

@razvand How do we know if an error is unlikely()? Also, would we need to do this for every file in the codebase or do we need to do this for a subset of files?

[razvand]

@pranjalrai4 , unlikely is typically used for error conditions. Whenever there is something that results in ending the current function / flow, that's probably a condition to be wrapped with unlikely. It's not a rule, but it's often the case.

[ggracechoi]

@razvand What is the selector and component for this issue? I want to confirm before committing our changes : )

[razvand]

@ggracechoi , if it touches multiple libraries, use lib/* as the selector.