[POWERPC] Fix bugs in the hypervisor call stats code

There were a few issues with the HCALL_STATS code:

- PURR cpu feature checks were backwards
- We iterated one entry off the end of the hcall_stats array
- Remove dead update_hcall_stats() function prototype

I noticed one thing while debugging, and that is we call H_ENTER (to set
up the MMU hashtable in early init) before we have done the cpu fixups.
This means we will execute the PURR SPR reads even on a CPU that isnt
capable of it. I wonder if we can move the CPU feature fixups earlier.

Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>

3 files changed, 5 insertions, 7 deletions

diff --git a/arch/powerpc/platforms/pseries/hvCall.S b/arch/powerpc/platforms/pseries/hvCall.S
index 527da445aaa..5c7e3878989 100644
--- a/arch/powerpc/platforms/pseries/hvCall.S
+++ b/arch/powerpc/platforms/pseries/hvCall.S
@@ -26,7 +26,7 @@
 BEGIN_FTR_SECTION;                                              \
         mfspr   r0,SPRN_PURR;           /* get PURR and */      \
         std     r0,STK_PARM(r6)(r1);    /* save for later */    \
-END_FTR_SECTION_IFCLR(CPU_FTR_PURR);
+END_FTR_SECTION_IFSET(CPU_FTR_PURR);
         
 /*
  * postcall is performed immediately before function return which
@@ -43,7 +43,7 @@ BEGIN_FTR_SECTION;						\
         mfspr   r8,SPRN_PURR;           /* PURR after */        \
         ld      r6,STK_PARM(r6)(r1);    /* PURR before */       \
         subf    r6,r6,r8;               /* delta */             \
-END_FTR_SECTION_IFCLR(CPU_FTR_PURR);                            \
+END_FTR_SECTION_IFSET(CPU_FTR_PURR);                            \
         ld      r5,STK_PARM(r5)(r1);    /* timebase before */   \
         subf    r5,r5,r7;               /* time delta */        \
                                                                 \
@@ -66,7 +66,7 @@ BEGIN_FTR_SECTION;						\
         ld      r7,HCALL_STAT_PURR(r4); /* PURR */              \
         add     r7,r7,r6;                                       \
         std     r7,HCALL_STAT_PURR(r4);                         \
-END_FTR_SECTION_IFCLR(CPU_FTR_PURR);                            \
+END_FTR_SECTION_IFSET(CPU_FTR_PURR);                            \
 1:
 #else
 #define HCALL_INST_PRECALL
diff --git a/arch/powerpc/platforms/pseries/hvCall_inst.c b/arch/powerpc/platforms/pseries/hvCall_inst.c
index 80181c4c49e..3ddc04925d5 100644
--- a/arch/powerpc/platforms/pseries/hvCall_inst.c
+++ b/arch/powerpc/platforms/pseries/hvCall_inst.c
@@ -34,7 +34,7 @@ DEFINE_PER_CPU(struct hcall_stats[HCALL_STAT_ARRAY_SIZE], hcall_stats);
  */
 static void *hc_start(struct seq_file *m, loff_t *pos)
 {
-        if ((int)*pos < HCALL_STAT_ARRAY_SIZE)
+        if ((int)*pos < (HCALL_STAT_ARRAY_SIZE-1))
                 return (void *)(unsigned long)(*pos + 1);
 
         return NULL;
@@ -57,7 +57,7 @@ static int hc_show(struct seq_file *m, void *p)
         struct hcall_stats *hs = (struct hcall_stats *)m->private;
 
         if (hs[h_num].num_calls) {
-                if (!cpu_has_feature(CPU_FTR_PURR))
+                if (cpu_has_feature(CPU_FTR_PURR))
                         seq_printf(m, "%lu %lu %lu %lu\n", h_num<<2,
                                    hs[h_num].num_calls,
                                    hs[h_num].tb_total,
diff --git a/include/asm-powerpc/hvcall.h b/include/asm-powerpc/hvcall.h
index 257d1cecb8c..7a500732b67 100644
--- a/include/asm-powerpc/hvcall.h
+++ b/include/asm-powerpc/hvcall.h
@@ -252,8 +252,6 @@ struct hcall_stats {
         unsigned long   tb_total;       /* total wall time (mftb) of calls. */
         unsigned long   purr_total;     /* total cpu time (PURR) of calls. */
 };
-void update_hcall_stats(unsigned long opcode, unsigned long tb_delta,
-                        unsigned long purr_delta);
 #define HCALL_STAT_ARRAY_SIZE   ((MAX_HCALL_OPCODE >> 2) + 1)
 
 #endif /* __ASSEMBLY__ */