Current SMP implementation for kexec has been added during kexec
development for Cavium Octeon platforms and doesn't apply to all other
SOCs.
Guard current implementation with a new config symbol
SYS_KEXEC_SMP_BOOT_SECONDARY that is enabled for Cavium Octeon.
Signed-off-by: Marcin Nowakowski <marcin.nowakowski@xxxxxxxxxx>
---
arch/mips/Kconfig | 5 +++++
arch/mips/include/asm/kexec.h | 2 ++
arch/mips/kernel/crash.c | 3 ++-
arch/mips/kernel/machine_kexec.c | 4 +++-
arch/mips/kernel/relocate_kernel.S | 6 +++---
5 files changed, 15 insertions(+), 5 deletions(-)
diff --git a/arch/mips/Kconfig b/arch/mips/Kconfig
index 9d07bee..77e6b5a 100644
--- a/arch/mips/Kconfig
+++ b/arch/mips/Kconfig
@@ -868,6 +868,7 @@ config CAVIUM_OCTEON_SOC
select SYS_SUPPORTS_HOTPLUG_CPU if CPU_BIG_ENDIAN
select SYS_HAS_EARLY_PRINTK
select SYS_HAS_CPU_CAVIUM_OCTEON
+ select SYS_KEXEC_SMP_BOOT_SECONDARY
select HW_HAS_PCI
select ZONE_DMA32
select HOLES_IN_ZONE
@@ -2780,6 +2781,7 @@ source "kernel/Kconfig.preempt"
config KEXEC
bool "Kexec system call"
select KEXEC_CORE
+ depends on SYS_KEXEC_SMP_BOOT_SECONDARY || !SMP
help
kexec is a system call that implements the ability to shutdown your
current kernel, and to start another kernel. It is like a reboot
@@ -2794,6 +2796,9 @@ config KEXEC
interface is strongly in flux, so no good recommendation can be
made.
+config SYS_KEXEC_SMP_BOOT_SECONDARY
+ bool
+
config CRASH_DUMP
bool "Kernel crash dumps"
help
diff --git a/arch/mips/include/asm/kexec.h b/arch/mips/include/asm/kexec.h
index 493a3cc..8934725 100644
--- a/arch/mips/include/asm/kexec.h
+++ b/arch/mips/include/asm/kexec.h
@@ -41,10 +41,12 @@ extern void (*_machine_kexec_shutdown)(void);
extern void (*_machine_crash_shutdown)(struct pt_regs *regs);
extern void default_machine_crash_shutdown(struct pt_regs *regs);
#ifdef CONFIG_SMP
+#ifdef CONFIG_SYS_KEXEC_SMP_BOOT_SECONDARY
extern const unsigned char kexec_smp_wait[];
extern unsigned long secondary_kexec_args[4];
extern void (*relocated_kexec_smp_wait) (void *);
extern atomic_t kexec_ready_to_reboot;
+#endif
extern void (*_crash_smp_send_stop)(void);
#endif
#endif
diff --git a/arch/mips/kernel/crash.c b/arch/mips/kernel/crash.c
index 5a71518..feeb3b0 100644
--- a/arch/mips/kernel/crash.c
+++ b/arch/mips/kernel/crash.c
@@ -38,11 +38,12 @@ static void crash_shutdown_secondary(void *passed_regs)
if (!cpumask_test_cpu(cpu, &cpus_in_crash))
crash_save_cpu(regs, cpu);
cpumask_set_cpu(cpu, &cpus_in_crash);
-
+#ifdef CONFIG_SYS_KEXEC_SMP_BOOT_SECONDARY
while (!atomic_read(&kexec_ready_to_reboot))
cpu_relax();
relocated_kexec_smp_wait(NULL);
/* NOTREACHED */
+#endif
}
static void crash_kexec_prepare_cpus(void)
diff --git a/arch/mips/kernel/machine_kexec.c b/arch/mips/kernel/machine_kexec.c
index 8b574bc..5f9a337 100644
--- a/arch/mips/kernel/machine_kexec.c
+++ b/arch/mips/kernel/machine_kexec.c
@@ -23,8 +23,10 @@ int (*_machine_kexec_prepare)(struct kimage *) = NULL;
void (*_machine_kexec_shutdown)(void) = NULL;
void (*_machine_crash_shutdown)(struct pt_regs *regs) = NULL;
#ifdef CONFIG_SMP
+#ifdef CONFIG_SYS_KEXEC_SMP_BOOT_SECONDARY
void (*relocated_kexec_smp_wait) (void *);
atomic_t kexec_ready_to_reboot = ATOMIC_INIT(0);
+#endif
void (*_crash_smp_send_stop)(void) = NULL;
#endif
@@ -126,7 +128,7 @@ machine_kexec(struct kimage *image)
printk("Will call new kernel at %08lx\n", image->start);
printk("Bye ...\n");
__flush_cache_all();
-#ifdef CONFIG_SMP
+#ifdef CONFIG_SYS_KEXEC_SMP_BOOT_SECONDARY
/* All secondary cpus now may jump to kexec_wait cycle */
relocated_kexec_smp_wait = reboot_code_buffer +
(void *)(kexec_smp_wait - relocate_new_kernel);
diff --git a/arch/mips/kernel/relocate_kernel.S b/arch/mips/kernel/relocate_kernel.S
index c6bbf21..dbdb963 100644
--- a/arch/mips/kernel/relocate_kernel.S
+++ b/arch/mips/kernel/relocate_kernel.S
@@ -69,7 +69,7 @@ copy_word:
b process_entry
done:
-#ifdef CONFIG_SMP
+#ifdef CONFIG_SYS_KEXEC_SMP_BOOT_SECONDARY
/* kexec_flag reset is signal to other CPUs what kernel
was moved to it's location. Note - we need relocated address
of kexec_flag. */
@@ -100,7 +100,7 @@ done:
j s1
END(relocate_new_kernel)
-#ifdef CONFIG_SMP
+#ifdef CONFIG_SYS_KEXEC_SMP_BOOT_SECONDARY
/*
* Other CPUs should wait until code is relocated and
* then start at entry (?) point.
@@ -156,7 +156,7 @@ arg2: PTR 0x0
arg3: PTR 0x0
.size kexec_args,PTRSIZE*4
-#ifdef CONFIG_SMP
+#ifdef CONFIG_SYS_KEXEC_SMP_BOOT_SECONDARY
/*
* Secondary CPUs may have different kernel parameters in
* their registers a0-a3. secondary_kexec_args[0..3] are used
--
2.7.4
