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![Guo Ren](/assets/img/avatar_default.png)
Use linux generic asid/vmid algorithm to implement csky switch_mm function. The algorithm is from arm and it could work with SMP system. It'll help reduce tlb flush for switch_mm in task/vm switch. Signed-off-by: Guo Ren <ren_guo@c-sky.com> Cc: Arnd Bergmann <arnd@arndb.de>
46 lines
1.1 KiB
C
46 lines
1.1 KiB
C
// SPDX-License-Identifier: GPL-2.0
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// Copyright (C) 2018 Hangzhou C-SKY Microsystems co.,ltd.
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#include <linux/bitops.h>
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#include <linux/sched.h>
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#include <linux/slab.h>
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#include <linux/mm.h>
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#include <asm/asid.h>
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#include <asm/mmu_context.h>
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#include <asm/smp.h>
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#include <asm/tlbflush.h>
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static DEFINE_PER_CPU(atomic64_t, active_asids);
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static DEFINE_PER_CPU(u64, reserved_asids);
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struct asid_info asid_info;
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void check_and_switch_context(struct mm_struct *mm, unsigned int cpu)
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{
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asid_check_context(&asid_info, &mm->context.asid, cpu, mm);
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}
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static void asid_flush_cpu_ctxt(void)
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{
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local_tlb_invalid_all();
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}
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static int asids_init(void)
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{
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BUG_ON(((1 << CONFIG_CPU_ASID_BITS) - 1) <= num_possible_cpus());
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if (asid_allocator_init(&asid_info, CONFIG_CPU_ASID_BITS, 1,
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asid_flush_cpu_ctxt))
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panic("Unable to initialize ASID allocator for %lu ASIDs\n",
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NUM_ASIDS(&asid_info));
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asid_info.active = &active_asids;
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asid_info.reserved = &reserved_asids;
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pr_info("ASID allocator initialised with %lu entries\n",
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NUM_CTXT_ASIDS(&asid_info));
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return 0;
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}
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early_initcall(asids_init);
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