Blackfin: rewrite resync_core_{i,d}cache() SMP logic to avoid per_cpu data

This functions are implicitly called by core functions like cpu_relax(),
and since those functions may be called early on before common code has
initialized the per-cpu data area, we need to tweak the stats gathering.
Now the statistics are maintained in common bss which makes these funcs
safe to use as soon as the C runtime env is setup.

Signed-off-by: Graf Yang <graf.yang@analog.com>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>

arch/blackfin/include/asm/cpu.h

@@ -17,8 +17,6 @@ struct blackfin_cpudata {
 	struct task_struct *idle;
 	unsigned int imemctl;
 	unsigned int dmemctl;
-	unsigned long dcache_invld_count;
-	unsigned long icache_invld_count;
 };
 
 DECLARE_PER_CPU(struct blackfin_cpudata, cpu_data);

arch/blackfin/include/asm/smp.h

@@ -24,6 +24,13 @@ struct corelock_slot {
 };
 extern struct corelock_slot corelock;
 
+#ifdef __ARCH_SYNC_CORE_ICACHE
+extern unsigned long icache_invld_count[NR_CPUS];
+#endif
+#ifdef __ARCH_SYNC_CORE_DCACHE
+extern unsigned long dcache_invld_count[NR_CPUS];
+#endif
+
 void smp_icache_flush_range_others(unsigned long start,
 				   unsigned long end);
 #ifdef CONFIG_HOTPLUG_CPU

arch/blackfin/kernel/setup.c

@@ -1239,10 +1239,10 @@ static int show_cpuinfo(struct seq_file *m, void *v)
 		   dsup_banks, BFIN_DSUBBANKS, BFIN_DWAYS,
 		   BFIN_DLINES);
 #ifdef __ARCH_SYNC_CORE_DCACHE
-	seq_printf(m, "SMP Dcache Flushes\t: %lu\n\n", cpudata->dcache_invld_count);
+	seq_printf(m, "SMP Dcache Flushes\t: %lu\n\n", dcache_invld_count[cpu_num]);
 #endif
 #ifdef __ARCH_SYNC_CORE_ICACHE
-	seq_printf(m, "SMP Icache Flushes\t: %lu\n\n", cpudata->icache_invld_count);
+	seq_printf(m, "SMP Icache Flushes\t: %lu\n\n", icache_invld_count[cpu_num]);
 #endif
 
 	if (cpu_num != num_possible_cpus() - 1)

arch/blackfin/mach-common/smp.c

@@ -474,24 +474,26 @@ void smp_icache_flush_range_others(unsigned long start, unsigned long end)
 EXPORT_SYMBOL_GPL(smp_icache_flush_range_others);
 
 #ifdef __ARCH_SYNC_CORE_ICACHE
+unsigned long icache_invld_count[NR_CPUS];
 void resync_core_icache(void)
 {
 	unsigned int cpu = get_cpu();
 	blackfin_invalidate_entire_icache();
-	++per_cpu(cpu_data, cpu).icache_invld_count;
+	icache_invld_count[cpu]++;
 	put_cpu();
 }
 EXPORT_SYMBOL(resync_core_icache);
 #endif
 
 #ifdef __ARCH_SYNC_CORE_DCACHE
+unsigned long dcache_invld_count[NR_CPUS];
 unsigned long barrier_mask __attribute__ ((__section__(".l2.bss")));
 
 void resync_core_dcache(void)
 {
 	unsigned int cpu = get_cpu();
 	blackfin_invalidate_entire_dcache();
-	++per_cpu(cpu_data, cpu).dcache_invld_count;
+	dcache_invld_count[cpu]++;
 	put_cpu();
 }
 EXPORT_SYMBOL(resync_core_dcache);