Remove uarch counters

We'll re-add support for the generic performance counter facility once
it exists.

pk/handlers.c

@@ -14,13 +14,6 @@ static void handle_illegal_instruction(trapframe_t* tf)
   else
     kassert(len == 2);
 
-  // supply 0 for unimplemented uarch counters
-  if ((tf->insn & (MASK_CSRRS | 0xcc0U<<20)) == (MATCH_CSRRS | 0xcc0U<<20)) {
-    tf->gpr[(tf->insn >> 7) & 0x1f] = 0;
-    tf->epc += 4;
-    return;
-  }
-
   dump_tf(tf);
   panic("An illegal instruction was executed!");
 }

pk/pk.c

@@ -8,42 +8,6 @@
 
 elf_info current;
 
-#define NUM_COUNTERS 18
-static int uarch_counters_enabled;
-static long uarch_counters[NUM_COUNTERS];
-static char* uarch_counter_names[NUM_COUNTERS];
-
-static void read_uarch_counters(bool dump)
-{
-  if (!uarch_counters_enabled)
-    return;
-
-  size_t i = 0;
-  #define READ_CTR(name) do { \
-    while (i >= NUM_COUNTERS) ; \
-    long csr = read_csr(name); \
-    if (dump && csr) printk("%s = %ld\n", #name, csr - uarch_counters[i]); \
-    uarch_counters[i++] = csr; \
-  } while (0)
-  READ_CTR(0xcc0); READ_CTR(0xcc1); READ_CTR(0xcc2);
-  READ_CTR(0xcc3); READ_CTR(0xcc4); READ_CTR(0xcc5);
-  READ_CTR(0xcc6); READ_CTR(0xcc7); READ_CTR(0xcc8);
-  READ_CTR(0xcc9); READ_CTR(0xcca); READ_CTR(0xccb);
-  READ_CTR(0xccc); READ_CTR(0xccd); READ_CTR(0xcce);
-  READ_CTR(0xccf); READ_CTR(cycle); READ_CTR(instret);
-  #undef READ_CTR
-}
-
-static void start_uarch_counters()
-{
-  read_uarch_counters(false);
-}
-
-void dump_uarch_counters()
-{
-  read_uarch_counters(true);
-}
-
 static void handle_option(const char* s)
 {
   switch (s[1])
@@ -52,10 +16,6 @@ static void handle_option(const char* s)
       current.t0 = 1;
       break;
 
-    case 'c': // print uarch counters upon termination
-      uarch_counters_enabled = 1;
-      break;
-
     default:
       panic("unrecognized option: `%c'", s[1]);
       break;
@@ -148,8 +108,6 @@ static void run_loaded_program(size_t argc, char** argv, uintptr_t kstack_top)
   if (current.t0) // start timer if so requested
     current.t0 = rdcycle();
 
-  start_uarch_counters();
-
   trapframe_t tf;
   init_tf(&tf, current.entry, stack_top);
   __clear_cache(0, 0);

pk/pk.h

@@ -35,7 +35,6 @@ int vsnprintf(char* out, size_t n, const char* s, va_list vl);
 int snprintf(char* out, size_t n, const char* s, ...);
 void start_user(trapframe_t* tf) __attribute__((noreturn));
 void dump_tf(trapframe_t*);
-void dump_uarch_counters();
 
 static inline int insn_len(long insn)
 {

pk/syscall.c

@@ -17,7 +17,6 @@ void sys_exit(int code)
 {
   if (current.t0)
     printk("%ld cycles\n", rdcycle() - current.t0);
-  dump_uarch_counters();
   shutdown(code);
 }