Start of an experiment to remove the use of gs for cpu local variables.

console.c

@@ -111,7 +111,7 @@ panic(char *s)
 
   cli();
   cons.locking = 0;
-  cprintf("cpu with apicid %d: panic: ", cpu->apicid);
+  cprintf("cpu %d: panic: ", cpuid());
   cprintf(s);
   cprintf("\n");
   getcallerpcs(&s, pcs);
@@ -242,7 +242,7 @@ consoleread(struct inode *ip, char *dst, int n)
   acquire(&cons.lock);
   while(n > 0){
     while(input.r == input.w){
-      if(proc->killed){
+      if(myproc()->killed){
         release(&cons.lock);
         ilock(ip);
         return -1;

defs.h

@@ -74,7 +74,7 @@ void            kbdintr(void);
 
 // lapic.c
 void            cmostime(struct rtcdate *r);
-int             cpunum(void);
+int             lapiccpunum(void);
 extern volatile uint*    lapic;
 void            lapiceoi(void);
 void            lapicinit(void);
@@ -103,6 +103,7 @@ int             pipewrite(struct pipe*, char*, int);
 
 //PAGEBREAK: 16
 // proc.c
+int             cpuid(void);
 void            exit(void);
 int             fork(void);
 int             growproc(int);
@@ -111,6 +112,7 @@ void            pinit(void);
 void            procdump(void);
 void            scheduler(void) __attribute__((noreturn));
 void            sched(void);
+void            setproc(struct proc*);
 void            sleep(void*, struct spinlock*);
 void            userinit(void);
 int             wait(void);

exec.c

@@ -22,6 +22,7 @@ exec(char *path, char **argv)
 
   if((ip = namei(path)) == 0){
     end_op();
+    cprintf("exec: fail\n");
     return -1;
   }
   ilock(ip);
@@ -89,15 +90,15 @@ exec(char *path, char **argv)
   for(last=s=path; *s; s++)
     if(*s == '/')
       last = s+1;
-  safestrcpy(proc->name, last, sizeof(proc->name));
+  safestrcpy(myproc()->name, last, sizeof(myproc()->name));
 
   // Commit to the user image.
-  oldpgdir = proc->pgdir;
-  proc->pgdir = pgdir;
-  proc->sz = sz;
-  proc->tf->eip = elf.entry;  // main
-  proc->tf->esp = sp;
-  switchuvm(proc);
+  oldpgdir = myproc()->pgdir;
+  myproc()->pgdir = pgdir;
+  myproc()->sz = sz;
+  myproc()->tf->eip = elf.entry;  // main
+  myproc()->tf->esp = sp;
+  switchuvm(myproc());
   freevm(oldpgdir);
   return 0;
 

fs.c

@@ -169,7 +169,7 @@ iinit(int dev)
   for(i = 0; i < NINODE; i++) {
     initsleeplock(&icache.inode[i].lock, "inode");
   }
-  
+
   readsb(dev, &sb);
   cprintf("sb: size %d nblocks %d ninodes %d nlog %d logstart %d\
  inodestart %d bmap start %d\n", sb.size, sb.nblocks,
@@ -615,7 +615,7 @@ namex(char *path, int nameiparent, char *name)
   if(*path == '/')
     ip = iget(ROOTDEV, ROOTINO);
   else
-    ip = idup(proc->cwd);
+    ip = idup(myproc()->cwd);
 
   while((path = skipelem(path, name)) != 0){
     ilock(ip);

ide.c

@@ -108,9 +108,9 @@ ideintr(void)
 
   // First queued buffer is the active request.
   acquire(&idelock);
+
   if((b = idequeue) == 0){
     release(&idelock);
-    // cprintf("spurious IDE interrupt\n");
     return;
   }
   idequeue = b->qnext;
@@ -164,5 +164,6 @@ iderw(struct buf *b)
     sleep(b, &idelock);
   }
 
+
   release(&idelock);
 }

lapic.c

@@ -99,19 +99,19 @@ lapicinit(void)
 }
 
 int
-cpunum(void)
+lapiccpunum(void)
 {
   int apicid, i;
 
-  // Cannot call cpu when interrupts are enabled:
+  // Cannot call cpunum when interrupts are enabled:
   // result not guaranteed to last long enough to be used!
   // Would prefer to panic but even printing is chancy here:
   // almost everything, including cprintf and panic, calls cpu,
   // often indirectly through acquire and release.
   if(readeflags()&FL_IF){
     static int n;
     if(n++ == 0)
-      cprintf("cpu called from %x with interrupts enabled\n",
+      cprintf("cpunum called from %x with interrupts enabled\n",
         __builtin_return_address(0));
   }
 

main.c

@@ -22,7 +22,6 @@ main(void)
   mpinit();        // detect other processors
   lapicinit();     // interrupt controller
   seginit();       // segment descriptors
-  cprintf("\ncpu%d: starting xv6\n\n", cpunum());
   picinit();       // another interrupt controller
   ioapicinit();    // another interrupt controller
   consoleinit();   // console hardware
@@ -31,7 +30,7 @@ main(void)
   tvinit();        // trap vectors
   binit();         // buffer cache
   fileinit();      // file table
-  ideinit();       // disk
+  ideinit();       // disk 
   if(!ismp)
     timerinit();   // uniprocessor timer
   startothers();   // start other processors
@@ -54,9 +53,9 @@ mpenter(void)
 static void
 mpmain(void)
 {
-  cprintf("cpu%d: starting\n", cpunum());
+  cprintf("cpu%d: starting %d\n", cpuid(), lapiccpunum());
   idtinit();       // load idt register
-  xchg(&cpu->started, 1); // tell startothers() we're up
+  xchg(&(mycpu()->started), 1); // tell startothers() we're up
   scheduler();     // start running processes
 }
 
@@ -78,7 +77,7 @@ startothers(void)
   memmove(code, _binary_entryother_start, (uint)_binary_entryother_size);
 
   for(c = cpus; c < cpus+ncpu; c++){
-    if(c == cpus+cpunum())  // We've started already.
+    if(c == mycpu())  // We've started already.
       continue;
 
     // Tell entryother.S what stack to use, where to enter, and what

pipe.c

@@ -83,7 +83,7 @@ pipewrite(struct pipe *p, char *addr, int n)
   acquire(&p->lock);
   for(i = 0; i < n; i++){
     while(p->nwrite == p->nread + PIPESIZE){  //DOC: pipewrite-full
-      if(p->readopen == 0 || proc->killed){
+      if(p->readopen == 0 || myproc()->killed){
         release(&p->lock);
         return -1;
       }
@@ -104,7 +104,7 @@ piperead(struct pipe *p, char *addr, int n)
 
   acquire(&p->lock);
   while(p->nread == p->nwrite && p->writeopen){  //DOC: pipe-empty
-    if(proc->killed){
+    if(myproc()->killed){
       release(&p->lock);
       return -1;
     }