From ab83647fadae2f1f723119dc066b39a461d6d288 Mon Sep 17 00:00:00 2001 From: Alexandre Ghiti Date: Sun, 3 Nov 2024 15:51:53 +0100 Subject: riscv: Add qspinlock support In order to produce a generic kernel, a user can select CONFIG_COMBO_SPINLOCKS which will fallback at runtime to the ticket spinlock implementation if Zabha or Ziccrse are not present. Note that we can't use alternatives here because the discovery of extensions is done too late and we need to start with the qspinlock implementation because the ticket spinlock implementation would pollute the spinlock value, so let's use static keys. This is largely based on Guo's work and Leonardo reviews at [1]. Link: https://lore.kernel.org/linux-riscv/20231225125847.2778638-1-guoren@kernel.org/ [1] Signed-off-by: Guo Ren Signed-off-by: Alexandre Ghiti Reviewed-by: Andrea Parri Link: https://lore.kernel.org/r/20241103145153.105097-14-alexghiti@rivosinc.com Signed-off-by: Palmer Dabbelt --- include/asm-generic/qspinlock.h | 2 ++ 1 file changed, 2 insertions(+) (limited to 'include/asm-generic/qspinlock.h') diff --git a/include/asm-generic/qspinlock.h b/include/asm-generic/qspinlock.h index 0655aa5b57b2..bf47cca2c375 100644 --- a/include/asm-generic/qspinlock.h +++ b/include/asm-generic/qspinlock.h @@ -136,6 +136,7 @@ static __always_inline bool virt_spin_lock(struct qspinlock *lock) } #endif +#ifndef __no_arch_spinlock_redefine /* * Remapping spinlock architecture specific functions to the corresponding * queued spinlock functions. @@ -146,5 +147,6 @@ static __always_inline bool virt_spin_lock(struct qspinlock *lock) #define arch_spin_lock(l) queued_spin_lock(l) #define arch_spin_trylock(l) queued_spin_trylock(l) #define arch_spin_unlock(l) queued_spin_unlock(l) +#endif #endif /* __ASM_GENERIC_QSPINLOCK_H */ -- cgit v1.2.3