diff options
Diffstat (limited to 'proc.h')
| -rw-r--r-- | proc.h | 12 |
1 files changed, 4 insertions, 8 deletions
@@ -43,19 +43,15 @@ struct proc { char name[16]; // Process name (debugging) }; -// Process memory is laid out contiguously: +// Process memory is laid out contiguously, low addresses first: // text // original data and bss // fixed-size stack // expandable heap -// If xv6 was only for uniprocessors, this could be -// struct proc *cp; -// Instead we have an array curproc, one per -// processor, and #define cp to the right element -// in the array. In general such preprocessor -// subterfuge is to be avoided, but cp is used -// so often that having the shorthand is worth the ugliness. +// Arrange that cp point to the struct proc that this +// CPU is currently running. Such preprocessor +// subterfuge can be confusing, but saves a lot of typing. extern struct proc *curproc[NCPU]; // Current (running) process per CPU #define cp (curproc[cpu()]) // Current process on this CPU |