diff options
Diffstat (limited to 'arch/riscv/include/asm/simd.h')
| -rw-r--r-- | arch/riscv/include/asm/simd.h | 26 |
1 files changed, 21 insertions, 5 deletions
diff --git a/arch/riscv/include/asm/simd.h b/arch/riscv/include/asm/simd.h index 4d699e16c9a9..54efbf523d49 100644 --- a/arch/riscv/include/asm/simd.h +++ b/arch/riscv/include/asm/simd.h @@ -12,6 +12,7 @@ #include <linux/percpu.h> #include <linux/preempt.h> #include <linux/types.h> +#include <linux/thread_info.h> #include <asm/vector.h> @@ -28,12 +29,27 @@ static __must_check inline bool may_use_simd(void) /* * RISCV_KERNEL_MODE_V is only set while preemption is disabled, * and is clear whenever preemption is enabled. - * - * Kernel-mode Vector temporarily disables bh. So we must not return - * true on irq_disabled(). Otherwise we would fail the lockdep check - * calling local_bh_enable() */ - return !in_hardirq() && !in_nmi() && !irqs_disabled() && !(riscv_v_flags() & RISCV_KERNEL_MODE_V); + if (in_hardirq() || in_nmi()) + return false; + + /* + * Nesting is acheived in preempt_v by spreading the control for + * preemptible and non-preemptible kernel-mode Vector into two fields. + * Always try to match with prempt_v if kernel V-context exists. Then, + * fallback to check non preempt_v if nesting happens, or if the config + * is not set. + */ + if (IS_ENABLED(CONFIG_RISCV_ISA_V_PREEMPTIVE) && current->thread.kernel_vstate.datap) { + if (!riscv_preempt_v_started(current)) + return true; + } + /* + * Non-preemptible kernel-mode Vector temporarily disables bh. So we + * must not return true on irq_disabled(). Otherwise we would fail the + * lockdep check calling local_bh_enable() + */ + return !irqs_disabled() && !(riscv_v_flags() & RISCV_KERNEL_MODE_V); } #else /* ! CONFIG_RISCV_ISA_V */ |