aboutsummaryrefslogtreecommitdiff
path: root/arch/powerpc/kernel/crash.c
diff options
context:
space:
mode:
Diffstat (limited to 'arch/powerpc/kernel/crash.c')
-rw-r--r--arch/powerpc/kernel/crash.c33
1 files changed, 26 insertions, 7 deletions
diff --git a/arch/powerpc/kernel/crash.c b/arch/powerpc/kernel/crash.c
index d4467557b00..b942980e965 100644
--- a/arch/powerpc/kernel/crash.c
+++ b/arch/powerpc/kernel/crash.c
@@ -30,6 +30,20 @@
#include <asm/system.h>
#include <asm/setjmp.h>
+/*
+ * The primary CPU waits a while for all secondary CPUs to enter. This is to
+ * avoid sending an IPI if the secondary CPUs are entering
+ * crash_kexec_secondary on their own (eg via a system reset).
+ *
+ * The secondary timeout has to be longer than the primary. Both timeouts are
+ * in milliseconds.
+ */
+#define PRIMARY_TIMEOUT 500
+#define SECONDARY_TIMEOUT 1000
+
+#define IPI_TIMEOUT 10000
+#define REAL_MODE_TIMEOUT 10000
+
/* This keeps a track of which one is the crashing cpu. */
int crashing_cpu = -1;
static cpumask_t cpus_in_crash = CPU_MASK_NONE;
@@ -99,11 +113,9 @@ again:
* FIXME: Until we will have the way to stop other CPUs reliably,
* the crash CPU will send an IPI and wait for other CPUs to
* respond.
- * Delay of at least 10 seconds.
*/
- msecs = 10000;
+ msecs = IPI_TIMEOUT;
while ((cpumask_weight(&cpus_in_crash) < ncpus) && (--msecs > 0)) {
- cpu_relax();
mdelay(1);
}
@@ -163,11 +175,11 @@ again:
void crash_kexec_secondary(struct pt_regs *regs)
{
unsigned long flags;
- int msecs = 500;
+ int msecs = SECONDARY_TIMEOUT;
local_irq_save(flags);
- /* Wait 500ms for the primary crash CPU to signal its progress */
+ /* Wait for the primary crash CPU to signal its progress */
while (crashing_cpu < 0) {
if (--msecs < 0) {
/* No response, kdump image may not have been loaded */
@@ -176,7 +188,6 @@ void crash_kexec_secondary(struct pt_regs *regs)
}
mdelay(1);
- cpu_relax();
}
crash_ipi_callback(regs);
@@ -211,7 +222,7 @@ static void crash_kexec_wait_realmode(int cpu)
unsigned int msecs;
int i;
- msecs = 10000;
+ msecs = REAL_MODE_TIMEOUT;
for (i=0; i < nr_cpu_ids && msecs > 0; i++) {
if (i == cpu)
continue;
@@ -306,6 +317,14 @@ void default_machine_crash_shutdown(struct pt_regs *regs)
*/
crashing_cpu = smp_processor_id();
crash_save_cpu(regs, crashing_cpu);
+
+ /*
+ * If we came in via system reset, wait a while for the secondary
+ * CPUs to enter.
+ */
+ if (TRAP(regs) == 0x100)
+ mdelay(PRIMARY_TIMEOUT);
+
crash_kexec_prepare_cpus(crashing_cpu);
cpumask_set_cpu(crashing_cpu, &cpus_in_crash);
crash_kexec_wait_realmode(crashing_cpu);