[PATCH] riscv: Add riscv_force_qspinlock for early_param
guoren at kernel.org
guoren at kernel.org
Fri Dec 13 20:35:10 PST 2024
From: Guo Ren <guoren at linux.alibaba.com>
When CONFIG_RISCV_COMBO_SPINLOCKS is enabled, permit qspinlock
force enabled. See the Kconfig entry for RISCV_COMBO_SPINLOCKS.
Signed-off-by: Guo Ren <guoren at linux.alibaba.com>
Signed-off-by: Guo Ren <guoren at kernel.org>
---
Documentation/admin-guide/kernel-parameters.txt | 5 +++++
arch/riscv/kernel/setup.c | 13 ++++++++++++-
2 files changed, 17 insertions(+), 1 deletion(-)
diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt
index 3872bc6ec49d..43d0df2922b2 100644
--- a/Documentation/admin-guide/kernel-parameters.txt
+++ b/Documentation/admin-guide/kernel-parameters.txt
@@ -5887,6 +5887,11 @@
[KNL] Disable ring 3 MONITOR/MWAIT feature on supported
CPUs.
+ riscv_force_qspinlock [RISCV, EARLY]
+ When CONFIG_RISCV_COMBO_SPINLOCKS is enabled, permit
+ qspinlock force enabled. See the Kconfig entry for
+ RISCV_COMBO_SPINLOCKS.
+
riscv_isa_fallback [RISCV,EARLY]
When CONFIG_RISCV_ISA_FALLBACK is not enabled, permit
falling back to detecting extension support by parsing
diff --git a/arch/riscv/kernel/setup.c b/arch/riscv/kernel/setup.c
index 45010e71df86..74b13bc64c9c 100644
--- a/arch/riscv/kernel/setup.c
+++ b/arch/riscv/kernel/setup.c
@@ -247,6 +247,15 @@ static void __init parse_dtb(void)
#if defined(CONFIG_RISCV_COMBO_SPINLOCKS)
DEFINE_STATIC_KEY_TRUE(qspinlock_key);
EXPORT_SYMBOL(qspinlock_key);
+
+static bool force_qspinlock;
+
+static int __init riscv_force_qspinlock(char *p)
+{
+ force_qspinlock = true;
+ return 0;
+}
+early_param("riscv_force_qspinlock", riscv_force_qspinlock);
#endif
static void __init riscv_spinlock_init(void)
@@ -267,7 +276,9 @@ static void __init riscv_spinlock_init(void)
using_ext = "using Ziccrse";
}
#if defined(CONFIG_RISCV_COMBO_SPINLOCKS)
- else {
+ else if (force_qspinlock) {
+ using_ext = "force";
+ } else {
static_branch_disable(&qspinlock_key);
pr_info("Ticket spinlock: enabled\n");
return;
--
2.40.1
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