From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-20.7 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id BD29BC28CFA for ; Tue, 2 Mar 2021 10:11:14 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id A78D560240 for ; Tue, 2 Mar 2021 10:11:14 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1379889AbhCBKGQ (ORCPT ); Tue, 2 Mar 2021 05:06:16 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:35386 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1577833AbhCBJ4Q (ORCPT ); Tue, 2 Mar 2021 04:56:16 -0500 Received: from galois.linutronix.de (Galois.linutronix.de [IPv6:2a0a:51c0:0:12e:550::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id E7468C061756; Tue, 2 Mar 2021 01:55:35 -0800 (PST) Date: Tue, 02 Mar 2021 09:54:48 -0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1614678889; h=from:from:sender:sender:reply-to:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=cR/As0yJHHunPQEOQNUXPvS0bQKBpqfYGk3NV6yuCIE=; b=yf+r3jzyaMADXmKRco0H4yWdahyHd53gZIDCjzSJ7ZdY0DNuXb0C/e699FAHvrNuw6A39U E1kTJShWehmMDRRWQO88hrONu576Zzmenz9Vb3t10IGPrGijP31XlbdckefT5QmWbPI9Bh /ipWUKcux+o+lz068K9d0PqWkjuVBk7PWWnu6Vi+x9CWtGiuuotw+SZ/LP12pCkU9h0FTa DboICnlq2M4nrqCxAUa7ixjZC2jllEWUQksE/PsTmJULhSnjS3JF/gDfhM69Yr5n9AqtZa /dlj69vSLFqcY75YogrSEMnbAL5a9rJb8pXom9SyBK4rLxjDO9rBqqQs7sPIuA== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1614678889; h=from:from:sender:sender:reply-to:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=cR/As0yJHHunPQEOQNUXPvS0bQKBpqfYGk3NV6yuCIE=; b=orxR9gGIb4+5p38Pl0phVKbfPOW6gOZ8iz7DGBpjjQNmk+zio6JO4N/6gKG89bbPG9fb2g cu8JW7zIQhZwb4Bg== From: "tip-bot2 for Nadav Amit" Sender: tip-bot2@linutronix.de Reply-to: linux-kernel@vger.kernel.org To: linux-tip-commits@vger.kernel.org Subject: [tip: x86/mm] x86/mm/tlb: Unify flush_tlb_func_local() and flush_tlb_func_remote() Cc: Nadav Amit , Ingo Molnar , Dave Hansen , x86@kernel.org, linux-kernel@vger.kernel.org In-Reply-To: <20210220231712.2475218-3-namit@vmware.com> References: <20210220231712.2475218-3-namit@vmware.com> MIME-Version: 1.0 Message-ID: <161467888856.20312.8212211781672416767.tip-bot2@tip-bot2> Robot-ID: Robot-Unsubscribe: Contact to get blacklisted from these emails Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The following commit has been merged into the x86/mm branch of tip: Commit-ID: f4f14f7c20440a442b4eaeb7b6f25cd0fc437e36 Gitweb: https://git.kernel.org/tip/f4f14f7c20440a442b4eaeb7b6f25cd0fc437e36 Author: Nadav Amit AuthorDate: Sat, 20 Feb 2021 15:17:05 -08:00 Committer: Ingo Molnar CommitterDate: Tue, 02 Mar 2021 08:01:37 +01:00 x86/mm/tlb: Unify flush_tlb_func_local() and flush_tlb_func_remote() The unification of these two functions allows to use them in the updated SMP infrastrucutre. To do so, remove the reason argument from flush_tlb_func_local(), add a member to struct tlb_flush_info that says which CPU initiated the flush and act accordingly. Optimize the size of flush_tlb_info while we are at it. Unfortunately, this prevents us from using a constant tlb_flush_info for arch_tlbbatch_flush(), but in a later stage we may be able to inline tlb_flush_info into the IPI data, so it should not have an impact eventually. Signed-off-by: Nadav Amit Signed-off-by: Ingo Molnar Reviewed-by: Dave Hansen Link: https://lore.kernel.org/r/20210220231712.2475218-3-namit@vmware.com --- arch/x86/include/asm/tlbflush.h | 5 +- arch/x86/mm/tlb.c | 81 ++++++++++++++------------------ 2 files changed, 39 insertions(+), 47 deletions(-) diff --git a/arch/x86/include/asm/tlbflush.h b/arch/x86/include/asm/tlbflush.h index 8c87a2e..a7a598a 100644 --- a/arch/x86/include/asm/tlbflush.h +++ b/arch/x86/include/asm/tlbflush.h @@ -201,8 +201,9 @@ struct flush_tlb_info { unsigned long start; unsigned long end; u64 new_tlb_gen; - unsigned int stride_shift; - bool freed_tables; + unsigned int initiating_cpu; + u8 stride_shift; + u8 freed_tables; }; void flush_tlb_local(void); diff --git a/arch/x86/mm/tlb.c b/arch/x86/mm/tlb.c index 569ac1d..bf12371 100644 --- a/arch/x86/mm/tlb.c +++ b/arch/x86/mm/tlb.c @@ -439,7 +439,7 @@ void switch_mm_irqs_off(struct mm_struct *prev, struct mm_struct *next, * NB: leave_mm() calls us with prev == NULL and tsk == NULL. */ - /* We don't want flush_tlb_func_* to run concurrently with us. */ + /* We don't want flush_tlb_func() to run concurrently with us. */ if (IS_ENABLED(CONFIG_PROVE_LOCKING)) WARN_ON_ONCE(!irqs_disabled()); @@ -647,14 +647,13 @@ void initialize_tlbstate_and_flush(void) } /* - * flush_tlb_func_common()'s memory ordering requirement is that any + * flush_tlb_func()'s memory ordering requirement is that any * TLB fills that happen after we flush the TLB are ordered after we * read active_mm's tlb_gen. We don't need any explicit barriers * because all x86 flush operations are serializing and the * atomic64_read operation won't be reordered by the compiler. */ -static void flush_tlb_func_common(const struct flush_tlb_info *f, - bool local, enum tlb_flush_reason reason) +static void flush_tlb_func(void *info) { /* * We have three different tlb_gen values in here. They are: @@ -665,14 +664,26 @@ static void flush_tlb_func_common(const struct flush_tlb_info *f, * - f->new_tlb_gen: the generation that the requester of the flush * wants us to catch up to. */ + const struct flush_tlb_info *f = info; struct mm_struct *loaded_mm = this_cpu_read(cpu_tlbstate.loaded_mm); u32 loaded_mm_asid = this_cpu_read(cpu_tlbstate.loaded_mm_asid); u64 mm_tlb_gen = atomic64_read(&loaded_mm->context.tlb_gen); u64 local_tlb_gen = this_cpu_read(cpu_tlbstate.ctxs[loaded_mm_asid].tlb_gen); + bool local = smp_processor_id() == f->initiating_cpu; + unsigned long nr_invalidate = 0; /* This code cannot presently handle being reentered. */ VM_WARN_ON(!irqs_disabled()); + if (!local) { + inc_irq_stat(irq_tlb_count); + count_vm_tlb_event(NR_TLB_REMOTE_FLUSH_RECEIVED); + + /* Can only happen on remote CPUs */ + if (f->mm && f->mm != loaded_mm) + return; + } + if (unlikely(loaded_mm == &init_mm)) return; @@ -700,8 +711,7 @@ static void flush_tlb_func_common(const struct flush_tlb_info *f, * be handled can catch us all the way up, leaving no work for * the second flush. */ - trace_tlb_flush(reason, 0); - return; + goto done; } WARN_ON_ONCE(local_tlb_gen > mm_tlb_gen); @@ -748,46 +758,34 @@ static void flush_tlb_func_common(const struct flush_tlb_info *f, f->new_tlb_gen == local_tlb_gen + 1 && f->new_tlb_gen == mm_tlb_gen) { /* Partial flush */ - unsigned long nr_invalidate = (f->end - f->start) >> f->stride_shift; unsigned long addr = f->start; + nr_invalidate = (f->end - f->start) >> f->stride_shift; + while (addr < f->end) { flush_tlb_one_user(addr); addr += 1UL << f->stride_shift; } if (local) count_vm_tlb_events(NR_TLB_LOCAL_FLUSH_ONE, nr_invalidate); - trace_tlb_flush(reason, nr_invalidate); } else { /* Full flush. */ + nr_invalidate = TLB_FLUSH_ALL; + flush_tlb_local(); if (local) count_vm_tlb_event(NR_TLB_LOCAL_FLUSH_ALL); - trace_tlb_flush(reason, TLB_FLUSH_ALL); } /* Both paths above update our state to mm_tlb_gen. */ this_cpu_write(cpu_tlbstate.ctxs[loaded_mm_asid].tlb_gen, mm_tlb_gen); -} - -static void flush_tlb_func_local(const void *info, enum tlb_flush_reason reason) -{ - const struct flush_tlb_info *f = info; - - flush_tlb_func_common(f, true, reason); -} -static void flush_tlb_func_remote(void *info) -{ - const struct flush_tlb_info *f = info; - - inc_irq_stat(irq_tlb_count); - - if (f->mm && f->mm != this_cpu_read(cpu_tlbstate.loaded_mm)) - return; - - count_vm_tlb_event(NR_TLB_REMOTE_FLUSH_RECEIVED); - flush_tlb_func_common(f, false, TLB_REMOTE_SHOOTDOWN); + /* Tracing is done in a unified manner to reduce the code size */ +done: + trace_tlb_flush(!local ? TLB_REMOTE_SHOOTDOWN : + (f->mm == NULL) ? TLB_LOCAL_SHOOTDOWN : + TLB_LOCAL_MM_SHOOTDOWN, + nr_invalidate); } static bool tlb_is_not_lazy(int cpu, void *data) @@ -816,10 +814,10 @@ STATIC_NOPV void native_flush_tlb_others(const struct cpumask *cpumask, * doing a speculative memory access. */ if (info->freed_tables) - smp_call_function_many(cpumask, flush_tlb_func_remote, + smp_call_function_many(cpumask, flush_tlb_func, (void *)info, 1); else - on_each_cpu_cond_mask(tlb_is_not_lazy, flush_tlb_func_remote, + on_each_cpu_cond_mask(tlb_is_not_lazy, flush_tlb_func, (void *)info, 1, cpumask); } @@ -869,6 +867,7 @@ static inline struct flush_tlb_info *get_flush_tlb_info(struct mm_struct *mm, info->stride_shift = stride_shift; info->freed_tables = freed_tables; info->new_tlb_gen = new_tlb_gen; + info->initiating_cpu = smp_processor_id(); return info; } @@ -908,7 +907,7 @@ void flush_tlb_mm_range(struct mm_struct *mm, unsigned long start, if (mm == this_cpu_read(cpu_tlbstate.loaded_mm)) { lockdep_assert_irqs_enabled(); local_irq_disable(); - flush_tlb_func_local(info, TLB_LOCAL_MM_SHOOTDOWN); + flush_tlb_func(info); local_irq_enable(); } @@ -1119,34 +1118,26 @@ void __flush_tlb_all(void) } EXPORT_SYMBOL_GPL(__flush_tlb_all); -/* - * arch_tlbbatch_flush() performs a full TLB flush regardless of the active mm. - * This means that the 'struct flush_tlb_info' that describes which mappings to - * flush is actually fixed. We therefore set a single fixed struct and use it in - * arch_tlbbatch_flush(). - */ -static const struct flush_tlb_info full_flush_tlb_info = { - .mm = NULL, - .start = 0, - .end = TLB_FLUSH_ALL, -}; - void arch_tlbbatch_flush(struct arch_tlbflush_unmap_batch *batch) { + struct flush_tlb_info *info; + int cpu = get_cpu(); + info = get_flush_tlb_info(NULL, 0, TLB_FLUSH_ALL, 0, false, 0); if (cpumask_test_cpu(cpu, &batch->cpumask)) { lockdep_assert_irqs_enabled(); local_irq_disable(); - flush_tlb_func_local(&full_flush_tlb_info, TLB_LOCAL_SHOOTDOWN); + flush_tlb_func(info); local_irq_enable(); } if (cpumask_any_but(&batch->cpumask, cpu) < nr_cpu_ids) - flush_tlb_others(&batch->cpumask, &full_flush_tlb_info); + flush_tlb_others(&batch->cpumask, info); cpumask_clear(&batch->cpumask); + put_flush_tlb_info(); put_cpu(); }