[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-ID: <20240102220134.3229156-13-samuel.holland@sifive.com>
Date: Tue, 2 Jan 2024 14:00:49 -0800
From: Samuel Holland <samuel.holland@...ive.com>
To: Palmer Dabbelt <palmer@...belt.com>,
linux-riscv@...ts.infradead.org
Cc: linux-kernel@...r.kernel.org,
linux-mm@...ck.org,
Alexandre Ghiti <alexghiti@...osinc.com>,
Samuel Holland <samuel.holland@...ive.com>
Subject: [PATCH v4 12/12] riscv: mm: Always use an ASID to flush mm contexts
Even if multiple ASIDs are not supported, using the single-ASID variant
of the sfence.vma instruction preserves TLB entries for global (kernel)
pages. So it is always more efficient to use the single-ASID code path.
Signed-off-by: Samuel Holland <samuel.holland@...ive.com>
---
Changes in v4:
- There is now only one copy of __flush_tlb_range()
Changes in v2:
- Update both copies of __flush_tlb_range()
arch/riscv/include/asm/mmu_context.h | 2 --
arch/riscv/mm/context.c | 3 +--
arch/riscv/mm/tlbflush.c | 3 +--
3 files changed, 2 insertions(+), 6 deletions(-)
diff --git a/arch/riscv/include/asm/mmu_context.h b/arch/riscv/include/asm/mmu_context.h
index 7030837adc1a..b0659413a080 100644
--- a/arch/riscv/include/asm/mmu_context.h
+++ b/arch/riscv/include/asm/mmu_context.h
@@ -33,8 +33,6 @@ static inline int init_new_context(struct task_struct *tsk,
return 0;
}
-DECLARE_STATIC_KEY_FALSE(use_asid_allocator);
-
#include <asm-generic/mmu_context.h>
#endif /* _ASM_RISCV_MMU_CONTEXT_H */
diff --git a/arch/riscv/mm/context.c b/arch/riscv/mm/context.c
index 3ca9b653df7d..20057085ab8a 100644
--- a/arch/riscv/mm/context.c
+++ b/arch/riscv/mm/context.c
@@ -18,8 +18,7 @@
#ifdef CONFIG_MMU
-DEFINE_STATIC_KEY_FALSE(use_asid_allocator);
-
+static DEFINE_STATIC_KEY_FALSE(use_asid_allocator);
static unsigned long num_asids;
static atomic_long_t current_version;
diff --git a/arch/riscv/mm/tlbflush.c b/arch/riscv/mm/tlbflush.c
index 5ec621545c69..39d80f56d292 100644
--- a/arch/riscv/mm/tlbflush.c
+++ b/arch/riscv/mm/tlbflush.c
@@ -84,8 +84,7 @@ static void __flush_tlb_range(struct mm_struct *mm, unsigned long start,
if (cpumask_empty(cmask))
return;
- if (static_branch_unlikely(&use_asid_allocator))
- asid = cntx2asid(atomic_long_read(&mm->context.id));
+ asid = cntx2asid(atomic_long_read(&mm->context.id));
} else {
cmask = cpu_online_mask;
}
--
2.42.0
Powered by blists - more mailing lists