[PATCH 14/15] MIPS: smp-cps: Add nothreads kernel parameter

From: Paul Burton
Date: Tue Feb 02 2016 - 22:19:49 EST


When debugging a new system or core it can be useful to disable the use
of multithreading. Introduce a "nothreads" kernel command line parameter
that can be set in order to do so.

Signed-off-by: Paul Burton <paul.burton@xxxxxxxxxx>
---

arch/mips/kernel/smp-cps.c | 11 +++++++++++
1 file changed, 11 insertions(+)

diff --git a/arch/mips/kernel/smp-cps.c b/arch/mips/kernel/smp-cps.c
index 27f1c04..23c29fc 100644
--- a/arch/mips/kernel/smp-cps.c
+++ b/arch/mips/kernel/smp-cps.c
@@ -27,14 +27,25 @@
#include <asm/time.h>
#include <asm/uasm.h>

+static bool threads_disabled;
static DECLARE_BITMAP(core_power, NR_CPUS);

struct core_boot_config *mips_cps_core_bootcfg;

+static int __init setup_nothreads(char *s)
+{
+ threads_disabled = true;
+ return 0;
+}
+early_param("nothreads", setup_nothreads);
+
static unsigned core_vpe_count(unsigned core)
{
unsigned cfg;

+ if (threads_disabled)
+ return 1;
+
if ((!config_enabled(CONFIG_MIPS_MT_SMP) || !cpu_has_mipsmt)
&& (!config_enabled(CONFIG_CPU_MIPSR6) || !cpu_has_vp))
return 1;
--
2.7.0