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Diffstat (limited to 'arch/tile/kernel/smp.c')
-rw-r--r--arch/tile/kernel/smp.c90
1 files changed, 45 insertions, 45 deletions
diff --git a/arch/tile/kernel/smp.c b/arch/tile/kernel/smp.c
index 9575b37a8b7..01e8ab29f43 100644
--- a/arch/tile/kernel/smp.c
+++ b/arch/tile/kernel/smp.c
@@ -20,8 +20,13 @@
#include <linux/irq.h>
#include <linux/module.h>
#include <asm/cacheflush.h>
+#include <asm/homecache.h>
-HV_Topology smp_topology __write_once;
+/*
+ * We write to width and height with a single store in head_NN.S,
+ * so make the variable aligned to "long".
+ */
+HV_Topology smp_topology __write_once __aligned(sizeof(long));
EXPORT_SYMBOL(smp_topology);
#if CHIP_HAS_IPI()
@@ -36,6 +41,22 @@ static unsigned long __iomem *ipi_mappings[NR_CPUS];
/* Set by smp_send_stop() to avoid recursive panics. */
static int stopping_cpus;
+static void __send_IPI_many(HV_Recipient *recip, int nrecip, int tag)
+{
+ int sent = 0;
+ while (sent < nrecip) {
+ int rc = hv_send_message(recip, nrecip,
+ (HV_VirtAddr)&tag, sizeof(tag));
+ if (rc < 0) {
+ if (!stopping_cpus) /* avoid recursive panic */
+ panic("hv_send_message returned %d", rc);
+ break;
+ }
+ WARN_ONCE(rc == 0, "hv_send_message() returned zero\n");
+ sent += rc;
+ }
+}
+
void send_IPI_single(int cpu, int tag)
{
HV_Recipient recip = {
@@ -43,14 +64,13 @@ void send_IPI_single(int cpu, int tag)
.x = cpu % smp_width,
.state = HV_TO_BE_SENT
};
- int rc = hv_send_message(&recip, 1, (HV_VirtAddr)&tag, sizeof(tag));
- BUG_ON(rc <= 0);
+ __send_IPI_many(&recip, 1, tag);
}
void send_IPI_many(const struct cpumask *mask, int tag)
{
HV_Recipient recip[NR_CPUS];
- int cpu, sent;
+ int cpu;
int nrecip = 0;
int my_cpu = smp_processor_id();
for_each_cpu(cpu, mask) {
@@ -61,17 +81,7 @@ void send_IPI_many(const struct cpumask *mask, int tag)
r->x = cpu % smp_width;
r->state = HV_TO_BE_SENT;
}
- sent = 0;
- while (sent < nrecip) {
- int rc = hv_send_message(recip, nrecip,
- (HV_VirtAddr)&tag, sizeof(tag));
- if (rc <= 0) {
- if (!stopping_cpus) /* avoid recursive panic */
- panic("hv_send_message returned %d", rc);
- break;
- }
- sent += rc;
- }
+ __send_IPI_many(recip, nrecip, tag);
}
void send_IPI_allbutself(int tag)
@@ -82,25 +92,6 @@ void send_IPI_allbutself(int tag)
send_IPI_many(&mask, tag);
}
-
-/*
- * Provide smp_call_function_mask, but also run function locally
- * if specified in the mask.
- */
-void on_each_cpu_mask(const struct cpumask *mask, void (*func)(void *),
- void *info, bool wait)
-{
- int cpu = get_cpu();
- smp_call_function_many(mask, func, info, wait);
- if (cpumask_test_cpu(cpu, mask)) {
- local_irq_disable();
- func(info);
- local_irq_enable();
- }
- put_cpu();
-}
-
-
/*
* Functions related to starting/stopping cpus.
*/
@@ -114,10 +105,10 @@ static void smp_start_cpu_interrupt(void)
/* Handler to stop the current cpu. */
static void smp_stop_cpu_interrupt(void)
{
- set_cpu_online(smp_processor_id(), 0);
arch_local_irq_disable_all();
+ set_cpu_online(smp_processor_id(), 0);
for (;;)
- asm("nap");
+ asm("nap; nop");
}
/* This function calls the 'stop' function on all other CPUs in the system. */
@@ -127,6 +118,12 @@ void smp_send_stop(void)
send_IPI_allbutself(MSG_TAG_STOP_CPU);
}
+/* On panic, just wait; we may get an smp_send_stop() later on. */
+void panic_smp_self_stop(void)
+{
+ while (1)
+ asm("nap; nop");
+}
/*
* Dispatch code called from hv_message_intr() for HV_MSG_TILE hv messages.
@@ -175,21 +172,24 @@ static void ipi_flush_icache_range(void *info)
void flush_icache_range(unsigned long start, unsigned long end)
{
struct ipi_flush flush = { start, end };
- preempt_disable();
- on_each_cpu(ipi_flush_icache_range, &flush, 1);
- preempt_enable();
+
+ /* If invoked with irqs disabled, we can not issue IPIs. */
+ if (irqs_disabled())
+ flush_remote(0, HV_FLUSH_EVICT_L1I, NULL, 0, 0, 0,
+ NULL, NULL, 0);
+ else {
+ preempt_disable();
+ on_each_cpu(ipi_flush_icache_range, &flush, 1);
+ preempt_enable();
+ }
}
/* Called when smp_send_reschedule() triggers IRQ_RESCHEDULE. */
static irqreturn_t handle_reschedule_ipi(int irq, void *token)
{
- /*
- * Nothing to do here; when we return from interrupt, the
- * rescheduling will occur there. But do bump the interrupt
- * profiler count in the meantime.
- */
__get_cpu_var(irq_stat).irq_resched_count++;
+ scheduler_ipi();
return IRQ_HANDLED;
}
@@ -215,7 +215,7 @@ void __init ipi_init(void)
if (hv_get_ipi_pte(tile, KERNEL_PL, &pte) != 0)
panic("Failed to initialize IPI for cpu %d\n", cpu);
- offset = hv_pte_get_pfn(pte) << PAGE_SHIFT;
+ offset = PFN_PHYS(pte_pfn(pte));
ipi_mappings[cpu] = ioremap_prot(offset, PAGE_SIZE, pte);
}
#endif