sparc32: implement SMP IPIs using the generic functions
The current sparc32 SMP IPI generation is implemented the
cross call function. The cross call function uses IRQ15 the
NMI, this is has the effect that IPIs will interrupt IRQ
critical areas and hang the system. Typically on/after
spin_lock_irqsave calls can be aborted.
The cross call functionality must still exist to flush
cache/TLBS.
This patch provides CPU models a custom way to implement
generation of IPIs on the generic code's request. The
typical approach is to generate an IRQ for each IPI case.
After this patch each sparc32 SMP CPU model needs to
implement IPIs in order to function properly.
Signed-off-by: Daniel Hellstrom <daniel@gaisler.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/arch/sparc/Kconfig b/arch/sparc/Kconfig
index a56630d..63a027c 100644
--- a/arch/sparc/Kconfig
+++ b/arch/sparc/Kconfig
@@ -28,7 +28,7 @@
select HAVE_GENERIC_HARDIRQS
select GENERIC_HARDIRQS_NO_DEPRECATED
select GENERIC_IRQ_SHOW
-
+ select USE_GENERIC_SMP_HELPERS if SMP
config SPARC32
def_bool !64BIT
@@ -47,7 +47,6 @@
select HAVE_DYNAMIC_FTRACE
select HAVE_FTRACE_MCOUNT_RECORD
select HAVE_SYSCALL_TRACEPOINTS
- select USE_GENERIC_SMP_HELPERS if SMP
select RTC_DRV_CMOS
select RTC_DRV_BQ4802
select RTC_DRV_SUN4V
diff --git a/arch/sparc/include/asm/cpudata_32.h b/arch/sparc/include/asm/cpudata_32.h
index 31d48a0..a4c5a93 100644
--- a/arch/sparc/include/asm/cpudata_32.h
+++ b/arch/sparc/include/asm/cpudata_32.h
@@ -16,6 +16,10 @@
unsigned long clock_tick;
unsigned int multiplier;
unsigned int counter;
+#ifdef CONFIG_SMP
+ unsigned int irq_resched_count;
+ unsigned int irq_call_count;
+#endif
int prom_node;
int mid;
int next;
@@ -23,5 +27,6 @@
DECLARE_PER_CPU(cpuinfo_sparc, __cpu_data);
#define cpu_data(__cpu) per_cpu(__cpu_data, (__cpu))
+#define local_cpu_data() __get_cpu_var(__cpu_data)
#endif /* _SPARC_CPUDATA_H */
diff --git a/arch/sparc/include/asm/smp_32.h b/arch/sparc/include/asm/smp_32.h
index d7837dcb..7a8e6cb 100644
--- a/arch/sparc/include/asm/smp_32.h
+++ b/arch/sparc/include/asm/smp_32.h
@@ -50,12 +50,19 @@
void smp_boot_cpus(void);
void smp_store_cpu_info(int);
+void smp_resched_interrupt(void);
+void smp_call_function_single_interrupt(void);
+void smp_call_function_interrupt(void);
+
struct seq_file;
void smp_bogo(struct seq_file *);
void smp_info(struct seq_file *);
BTFIXUPDEF_CALL(void, smp_cross_call, smpfunc_t, cpumask_t, unsigned long, unsigned long, unsigned long, unsigned long)
BTFIXUPDEF_CALL(int, __hard_smp_processor_id, void)
+BTFIXUPDEF_CALL(void, smp_ipi_resched, int);
+BTFIXUPDEF_CALL(void, smp_ipi_single, int);
+BTFIXUPDEF_CALL(void, smp_ipi_mask_one, int);
BTFIXUPDEF_BLACKBOX(hard_smp_processor_id)
BTFIXUPDEF_BLACKBOX(load_current)
@@ -73,19 +80,8 @@
unsigned long arg3, unsigned long arg4)
{ smp_cross_call(func, cpu_online_map, arg1, arg2, arg3, arg4); }
-static inline int smp_call_function(void (*func)(void *info), void *info, int wait)
-{
- xc1((smpfunc_t)func, (unsigned long)info);
- return 0;
-}
-
-static inline int smp_call_function_single(int cpuid, void (*func) (void *info),
- void *info, int wait)
-{
- smp_cross_call((smpfunc_t)func, cpumask_of_cpu(cpuid),
- (unsigned long) info, 0, 0, 0);
- return 0;
-}
+extern void arch_send_call_function_single_ipi(int cpu);
+extern void arch_send_call_function_ipi_mask(const struct cpumask *mask);
static inline int cpu_logical_map(int cpu)
{
diff --git a/arch/sparc/kernel/irq_32.c b/arch/sparc/kernel/irq_32.c
index 197e1ba..9b89d842 100644
--- a/arch/sparc/kernel/irq_32.c
+++ b/arch/sparc/kernel/irq_32.c
@@ -206,6 +206,16 @@
{
int j;
+#ifdef CONFIG_SMP
+ seq_printf(p, "RES: ");
+ for_each_online_cpu(j)
+ seq_printf(p, "%10u ", cpu_data(j).irq_resched_count);
+ seq_printf(p, " IPI rescheduling interrupts\n");
+ seq_printf(p, "CAL: ");
+ for_each_online_cpu(j)
+ seq_printf(p, "%10u ", cpu_data(j).irq_call_count);
+ seq_printf(p, " IPI function call interrupts\n");
+#endif
seq_printf(p, "NMI: ");
for_each_online_cpu(j)
seq_printf(p, "%10u ", cpu_data(j).counter);
diff --git a/arch/sparc/kernel/smp_32.c b/arch/sparc/kernel/smp_32.c
index 4a1d5b7..2710602 100644
--- a/arch/sparc/kernel/smp_32.c
+++ b/arch/sparc/kernel/smp_32.c
@@ -123,13 +123,58 @@
void smp_send_reschedule(int cpu)
{
- /* See sparc64 */
+ /*
+ * CPU model dependent way of implementing IPI generation targeting
+ * a single CPU. The trap handler needs only to do trap entry/return
+ * to call schedule.
+ */
+ BTFIXUP_CALL(smp_ipi_resched)(cpu);
}
void smp_send_stop(void)
{
}
+void arch_send_call_function_single_ipi(int cpu)
+{
+ /* trigger one IPI single call on one CPU */
+ BTFIXUP_CALL(smp_ipi_single)(cpu);
+}
+
+void arch_send_call_function_ipi_mask(const struct cpumask *mask)
+{
+ int cpu;
+
+ /* trigger IPI mask call on each CPU */
+ for_each_cpu(cpu, mask)
+ BTFIXUP_CALL(smp_ipi_mask_one)(cpu);
+}
+
+void smp_resched_interrupt(void)
+{
+ local_cpu_data().irq_resched_count++;
+ /*
+ * do nothing, since it all was about calling re-schedule
+ * routine called by interrupt return code.
+ */
+}
+
+void smp_call_function_single_interrupt(void)
+{
+ irq_enter();
+ generic_smp_call_function_single_interrupt();
+ local_cpu_data().irq_call_count++;
+ irq_exit();
+}
+
+void smp_call_function_interrupt(void)
+{
+ irq_enter();
+ generic_smp_call_function_interrupt();
+ local_cpu_data().irq_call_count++;
+ irq_exit();
+}
+
void smp_flush_cache_all(void)
{
xc0((smpfunc_t) BTFIXUP_CALL(local_flush_cache_all));