lists.openwall.net   lists  /  announce  owl-users  owl-dev  john-users  john-dev  passwdqc-users  yescrypt  popa3d-users  /  oss-security  kernel-hardening  musl  sabotage  tlsify  passwords  /  crypt-dev  xvendor  /  Bugtraq  Full-Disclosure  linux-kernel  linux-netdev  linux-ext4  linux-hardening  linux-cve-announce  PHC 
Open Source and information security mailing list archives
 
Hash Suite: Windows password security audit tool. GUI, reports in PDF.
[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-ID: <20230710083914.18336-2-yangyicong@huawei.com>
Date:   Mon, 10 Jul 2023 16:39:11 +0800
From:   Yicong Yang <yangyicong@...wei.com>
To:     <akpm@...ux-foundation.org>, <catalin.marinas@....com>,
        <linux-mm@...ck.org>, <linux-arm-kernel@...ts.infradead.org>,
        <x86@...nel.org>, <mark.rutland@....com>, <ryan.roberts@....com>,
        <will@...nel.org>, <anshuman.khandual@....com>,
        <linux-doc@...r.kernel.org>
CC:     <corbet@....net>, <peterz@...radead.org>, <arnd@...db.de>,
        <punit.agrawal@...edance.com>, <linux-kernel@...r.kernel.org>,
        <darren@...amperecomputing.com>, <yangyicong@...ilicon.com>,
        <huzhanyuan@...o.com>, <lipeifeng@...o.com>,
        <zhangshiming@...o.com>, <guojian@...o.com>, <realmz6@...il.com>,
        <linux-mips@...r.kernel.org>, <openrisc@...ts.librecores.org>,
        <linuxppc-dev@...ts.ozlabs.org>, <linux-riscv@...ts.infradead.org>,
        <linux-s390@...r.kernel.org>, Barry Song <21cnbao@...il.com>,
        <wangkefeng.wang@...wei.com>, <xhao@...ux.alibaba.com>,
        <prime.zeng@...ilicon.com>, <Jonathan.Cameron@...wei.com>,
        Anshuman Khandual <khandual@...ux.vnet.ibm.com>,
        Barry Song <baohua@...nel.org>
Subject: [PATCH v10 1/4] mm/tlbbatch: Introduce arch_tlbbatch_should_defer()

From: Anshuman Khandual <khandual@...ux.vnet.ibm.com>

The entire scheme of deferred TLB flush in reclaim path rests on the
fact that the cost to refill TLB entries is less than flushing out
individual entries by sending IPI to remote CPUs. But architecture
can have different ways to evaluate that. Hence apart from checking
TTU_BATCH_FLUSH in the TTU flags, rest of the decision should be
architecture specific.

Signed-off-by: Anshuman Khandual <khandual@...ux.vnet.ibm.com>
[https://lore.kernel.org/linuxppc-dev/20171101101735.2318-2-khandual@linux.vnet.ibm.com/]
Signed-off-by: Yicong Yang <yangyicong@...ilicon.com>
[Rebase and fix incorrect return value type]
Reviewed-by: Kefeng Wang <wangkefeng.wang@...wei.com>
Reviewed-by: Anshuman Khandual <anshuman.khandual@....com>
Reviewed-by: Barry Song <baohua@...nel.org>
Reviewed-by: Xin Hao <xhao@...ux.alibaba.com>
Tested-by: Punit Agrawal <punit.agrawal@...edance.com>
---
 arch/x86/include/asm/tlbflush.h | 12 ++++++++++++
 mm/rmap.c                       |  9 +--------
 2 files changed, 13 insertions(+), 8 deletions(-)

diff --git a/arch/x86/include/asm/tlbflush.h b/arch/x86/include/asm/tlbflush.h
index 80450e1d5385..cf2a1de5d388 100644
--- a/arch/x86/include/asm/tlbflush.h
+++ b/arch/x86/include/asm/tlbflush.h
@@ -253,6 +253,18 @@ static inline void flush_tlb_page(struct vm_area_struct *vma, unsigned long a)
 	flush_tlb_mm_range(vma->vm_mm, a, a + PAGE_SIZE, PAGE_SHIFT, false);
 }
 
+static inline bool arch_tlbbatch_should_defer(struct mm_struct *mm)
+{
+	bool should_defer = false;
+
+	/* If remote CPUs need to be flushed then defer batch the flush */
+	if (cpumask_any_but(mm_cpumask(mm), get_cpu()) < nr_cpu_ids)
+		should_defer = true;
+	put_cpu();
+
+	return should_defer;
+}
+
 static inline u64 inc_mm_tlb_gen(struct mm_struct *mm)
 {
 	/*
diff --git a/mm/rmap.c b/mm/rmap.c
index 0c0d8857dfce..6480e526c154 100644
--- a/mm/rmap.c
+++ b/mm/rmap.c
@@ -688,17 +688,10 @@ static void set_tlb_ubc_flush_pending(struct mm_struct *mm, pte_t pteval)
  */
 static bool should_defer_flush(struct mm_struct *mm, enum ttu_flags flags)
 {
-	bool should_defer = false;
-
 	if (!(flags & TTU_BATCH_FLUSH))
 		return false;
 
-	/* If remote CPUs need to be flushed then defer batch the flush */
-	if (cpumask_any_but(mm_cpumask(mm), get_cpu()) < nr_cpu_ids)
-		should_defer = true;
-	put_cpu();
-
-	return should_defer;
+	return arch_tlbbatch_should_defer(mm);
 }
 
 /*
-- 
2.24.0

Powered by blists - more mailing lists

Powered by Openwall GNU/*/Linux Powered by OpenVZ