From 6384423f49c804dbca02add1945e0ccf922cb522 Mon Sep 17 00:00:00 2001 From: Atish Patra Date: Thu, 22 Aug 2019 00:51:49 -0700 Subject: [PATCH] RISC-V: Do not invoke SBI call if cpumask is empty SBI calls are expensive. If cpumask is empty, there is no need to trap via SBI as no remote tlb flushing is required. Signed-off-by: Atish Patra Reviewed-by: Christoph Hellwig Signed-off-by: Paul Walmsley --- arch/riscv/mm/tlbflush.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/arch/riscv/mm/tlbflush.c b/arch/riscv/mm/tlbflush.c index 24cd33d..9ecaf73 100644 --- a/arch/riscv/mm/tlbflush.c +++ b/arch/riscv/mm/tlbflush.c @@ -14,6 +14,9 @@ static void __sbi_tlb_flush_range(struct cpumask *cmask, unsigned long start, { struct cpumask hmask; + if (cpumask_empty(cmask)) + return; + riscv_cpuid_to_hartid_mask(cmask, &hmask); sbi_remote_sfence_vma(hmask.bits, start, size); } -- 2.7.4