From mboxrd@z Thu Jan 1 00:00:00 1970 From: Julien Grall Subject: [PATCH RFC 03/14] arm64/mm: Move bits to asid_info Date: Thu, 21 Mar 2019 16:36:12 +0000 Message-ID: <20190321163623.20219-4-julien.grall@arm.com> References: <20190321163623.20219-1-julien.grall@arm.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Received: from localhost (localhost [127.0.0.1]) by mm01.cs.columbia.edu (Postfix) with ESMTP id 4F7CD4A36C for ; Thu, 21 Mar 2019 12:36:49 -0400 (EDT) Received: from mm01.cs.columbia.edu ([127.0.0.1]) by localhost (mm01.cs.columbia.edu [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id k-Y7G8SwgxLr for ; Thu, 21 Mar 2019 12:36:47 -0400 (EDT) Received: from foss.arm.com (foss.arm.com [217.140.101.70]) by mm01.cs.columbia.edu (Postfix) with ESMTP id B01BE4A424 for ; Thu, 21 Mar 2019 12:36:47 -0400 (EDT) In-Reply-To: <20190321163623.20219-1-julien.grall@arm.com> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: kvmarm-bounces@lists.cs.columbia.edu Sender: kvmarm-bounces@lists.cs.columbia.edu To: linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, kvmarm@lists.cs.columbia.edu Cc: marc.zyngier@arm.com, catalin.marinas@arm.com, will.deacon@arm.com, Julien Grall List-Id: kvmarm@lists.cs.columbia.edu The variable bits hold information for a given ASID allocator. So move it to the asid_info structure. Because most of the macros were relying on bits, they are now taking an extra parameter that is a pointer to the asid_info structure. Signed-off-by: Julien Grall --- arch/arm64/mm/context.c | 59 +++++++++++++++++++++++++------------------------ 1 file changed, 30 insertions(+), 29 deletions(-) diff --git a/arch/arm64/mm/context.c b/arch/arm64/mm/context.c index cfe4c5f7abf3..da17ed6c7117 100644 --- a/arch/arm64/mm/context.c +++ b/arch/arm64/mm/context.c @@ -27,7 +27,6 @@ #include #include -static u32 asid_bits; static DEFINE_RAW_SPINLOCK(cpu_asid_lock); struct asid_info @@ -36,6 +35,7 @@ struct asid_info unsigned long *map; atomic64_t __percpu *active; u64 __percpu *reserved; + u32 bits; } asid_info; #define active_asid(info, cpu) *per_cpu_ptr((info)->active, cpu) @@ -46,17 +46,17 @@ static DEFINE_PER_CPU(u64, reserved_asids); static cpumask_t tlb_flush_pending; -#define ASID_MASK (~GENMASK(asid_bits - 1, 0)) -#define ASID_FIRST_VERSION (1UL << asid_bits) +#define ASID_MASK(info) (~GENMASK((info)->bits - 1, 0)) +#define ASID_FIRST_VERSION(info) (1UL << ((info)->bits)) #ifdef CONFIG_UNMAP_KERNEL_AT_EL0 -#define NUM_USER_ASIDS (ASID_FIRST_VERSION >> 1) -#define asid2idx(asid) (((asid) & ~ASID_MASK) >> 1) -#define idx2asid(idx) (((idx) << 1) & ~ASID_MASK) +#define NUM_USER_ASIDS(info) (ASID_FIRST_VERSION(info) >> 1) +#define asid2idx(info, asid) (((asid) & ~ASID_MASK(info)) >> 1) +#define idx2asid(info, idx) (((idx) << 1) & ~ASID_MASK(info)) #else -#define NUM_USER_ASIDS (ASID_FIRST_VERSION) -#define asid2idx(asid) ((asid) & ~ASID_MASK) -#define idx2asid(idx) asid2idx(idx) +#define NUM_USER_ASIDS(info) (ASID_FIRST_VERSION(info)) +#define asid2idx(info, asid) ((asid) & ~ASID_MASK(info)) +#define idx2asid(info, idx) asid2idx(info, idx) #endif /* Get the ASIDBits supported by the current CPU */ @@ -86,13 +86,13 @@ void verify_cpu_asid_bits(void) { u32 asid = get_cpu_asid_bits(); - if (asid < asid_bits) { + if (asid < asid_info.bits) { /* * We cannot decrease the ASID size at runtime, so panic if we support * fewer ASID bits than the boot CPU. */ pr_crit("CPU%d: smaller ASID size(%u) than boot CPU (%u)\n", - smp_processor_id(), asid, asid_bits); + smp_processor_id(), asid, asid_info.bits); cpu_panic_kernel(); } } @@ -103,7 +103,7 @@ static void flush_context(struct asid_info *info) u64 asid; /* Update the list of reserved ASIDs and the ASID bitmap. */ - bitmap_clear(info->map, 0, NUM_USER_ASIDS); + bitmap_clear(info->map, 0, NUM_USER_ASIDS(info)); for_each_possible_cpu(i) { asid = atomic64_xchg_relaxed(&active_asid(info, i), 0); @@ -116,7 +116,7 @@ static void flush_context(struct asid_info *info) */ if (asid == 0) asid = reserved_asid(info, i); - __set_bit(asid2idx(asid), info->map); + __set_bit(asid2idx(info, asid), info->map); reserved_asid(info, i) = asid; } @@ -159,7 +159,7 @@ static u64 new_context(struct asid_info *info, struct mm_struct *mm) u64 generation = atomic64_read(&info->generation); if (asid != 0) { - u64 newasid = generation | (asid & ~ASID_MASK); + u64 newasid = generation | (asid & ~ASID_MASK(info)); /* * If our current ASID was active during a rollover, we @@ -172,7 +172,7 @@ static u64 new_context(struct asid_info *info, struct mm_struct *mm) * We had a valid ASID in a previous life, so try to re-use * it if possible. */ - if (!__test_and_set_bit(asid2idx(asid), info->map)) + if (!__test_and_set_bit(asid2idx(info, asid), info->map)) return newasid; } @@ -183,22 +183,22 @@ static u64 new_context(struct asid_info *info, struct mm_struct *mm) * a reserved TTBR0 for the init_mm and we allocate ASIDs in even/odd * pairs. */ - asid = find_next_zero_bit(info->map, NUM_USER_ASIDS, cur_idx); - if (asid != NUM_USER_ASIDS) + asid = find_next_zero_bit(info->map, NUM_USER_ASIDS(info), cur_idx); + if (asid != NUM_USER_ASIDS(info)) goto set_asid; /* We're out of ASIDs, so increment the global generation count */ - generation = atomic64_add_return_relaxed(ASID_FIRST_VERSION, + generation = atomic64_add_return_relaxed(ASID_FIRST_VERSION(info), &info->generation); flush_context(info); /* We have more ASIDs than CPUs, so this will always succeed */ - asid = find_next_zero_bit(info->map, NUM_USER_ASIDS, 1); + asid = find_next_zero_bit(info->map, NUM_USER_ASIDS(info), 1); set_asid: __set_bit(asid, info->map); cur_idx = asid; - return idx2asid(asid) | generation; + return idx2asid(info, asid) | generation; } void check_and_switch_context(struct mm_struct *mm, unsigned int cpu) @@ -228,7 +228,7 @@ void check_and_switch_context(struct mm_struct *mm, unsigned int cpu) */ old_active_asid = atomic64_read(&active_asid(info, cpu)); if (old_active_asid && - !((asid ^ atomic64_read(&info->generation)) >> asid_bits) && + !((asid ^ atomic64_read(&info->generation)) >> info->bits) && atomic64_cmpxchg_relaxed(&active_asid(info, cpu), old_active_asid, asid)) goto switch_mm_fastpath; @@ -236,7 +236,7 @@ void check_and_switch_context(struct mm_struct *mm, unsigned int cpu) raw_spin_lock_irqsave(&cpu_asid_lock, flags); /* Check that our ASID belongs to the current generation. */ asid = atomic64_read(&mm->context.id); - if ((asid ^ atomic64_read(&info->generation)) >> asid_bits) { + if ((asid ^ atomic64_read(&info->generation)) >> info->bits) { asid = new_context(info, mm); atomic64_set(&mm->context.id, asid); } @@ -272,23 +272,24 @@ static int asids_init(void) { struct asid_info *info = &asid_info; - asid_bits = get_cpu_asid_bits(); + info->bits = get_cpu_asid_bits(); /* * Expect allocation after rollover to fail if we don't have at least * one more ASID than CPUs. ASID #0 is reserved for init_mm. */ - WARN_ON(NUM_USER_ASIDS - 1 <= num_possible_cpus()); - atomic64_set(&info->generation, ASID_FIRST_VERSION); - info->map = kcalloc(BITS_TO_LONGS(NUM_USER_ASIDS), sizeof(*info->map), - GFP_KERNEL); + WARN_ON(NUM_USER_ASIDS(info) - 1 <= num_possible_cpus()); + atomic64_set(&info->generation, ASID_FIRST_VERSION(info)); + info->map = kcalloc(BITS_TO_LONGS(NUM_USER_ASIDS(info)), + sizeof(*info->map), GFP_KERNEL); if (!info->map) panic("Failed to allocate bitmap for %lu ASIDs\n", - NUM_USER_ASIDS); + NUM_USER_ASIDS(info)); info->active = &active_asids; info->reserved = &reserved_asids; - pr_info("ASID allocator initialised with %lu entries\n", NUM_USER_ASIDS); + pr_info("ASID allocator initialised with %lu entries\n", + NUM_USER_ASIDS(info)); return 0; } early_initcall(asids_init); -- 2.11.0