From: Zhenyu Ye <yezhenyu2@huawei.com>
To: Peter Zijlstra <peterz@infradead.org>
Cc: <mark.rutland@arm.com>, <will@kernel.org>,
<catalin.marinas@arm.com>, <aneesh.kumar@linux.ibm.com>,
<akpm@linux-foundation.org>, <npiggin@gmail.com>, <arnd@arndb.de>,
<rostedt@goodmis.org>, <maz@kernel.org>, <suzuki.poulose@arm.com>,
<tglx@linutronix.de>, <yuzhao@google.com>, <Dave.Martin@arm.com>,
<steven.price@arm.com>, <broonie@kernel.org>,
<guohanjun@huawei.com>, <linux-arm-kernel@lists.infradead.org>,
<linux-kernel@vger.kernel.org>, <linux-arch@vger.kernel.org>,
<linux-mm@kvack.org>, <arm@kernel.org>, <xiexiangyou@huawei.com>,
<prime.zeng@hisilicon.com>, <zhangshaokun@hisilicon.com>,
<kuhn.chenqun@huawei.com>
Subject: Re: [PATCH v1 5/6] mm: tlb: Provide flush_*_tlb_range wrappers
Date: Tue, 21 Apr 2020 22:18:57 +0800 [thread overview]
Message-ID: <8f6e877c-1462-441b-23ec-2a6bd3308099@huawei.com> (raw)
In-Reply-To: <20200420120916.GE20696@hirez.programming.kicks-ass.net>
Hi Peter,
On 2020/4/20 20:09, Peter Zijlstra wrote:
> On Fri, Apr 03, 2020 at 05:00:47PM +0800, Zhenyu Ye wrote:
>> This patch provides flush_{pte|pmd|pud|p4d}_tlb_range() in generic
>> code, which are expressed through the mmu_gather APIs. These
>> interface set tlb->cleared_* and finally call tlb_flush(), so we
>> can do the tlb invalidation according to the information in
>> struct mmu_gather.
>>
>> Signed-off-by: Zhenyu Ye <yezhenyu2@huawei.com>
>> ---
>> include/asm-generic/pgtable.h | 12 +++++++--
>> mm/pgtable-generic.c | 50 +++++++++++++++++++++++++++++++++++
>> 2 files changed, 60 insertions(+), 2 deletions(-)
>>
>> diff --git a/include/asm-generic/pgtable.h b/include/asm-generic/pgtable.h
>> index e2e2bef07dd2..2bedeee94131 100644
>> --- a/include/asm-generic/pgtable.h
>> +++ b/include/asm-generic/pgtable.h
>> @@ -1160,11 +1160,19 @@ static inline int pmd_free_pte_page(pmd_t *pmd, unsigned long addr)
>> * invalidate the entire TLB which is not desitable.
>> * e.g. see arch/arc: flush_pmd_tlb_range
>> */
>> -#define flush_pmd_tlb_range(vma, addr, end) flush_tlb_range(vma, addr, end)
>> -#define flush_pud_tlb_range(vma, addr, end) flush_tlb_range(vma, addr, end)
>> +extern void flush_pte_tlb_range(struct vm_area_struct *vma,
>> + unsigned long addr, unsigned long end);
>> +extern void flush_pmd_tlb_range(struct vm_area_struct *vma,
>> + unsigned long addr, unsigned long end);
>> +extern void flush_pud_tlb_range(struct vm_area_struct *vma,
>> + unsigned long addr, unsigned long end);
>> +extern void flush_p4d_tlb_range(struct vm_area_struct *vma,
>> + unsigned long addr, unsigned long end);
>> #else
>> +#define flush_pte_tlb_range(vma, addr, end) BUILD_BUG()
>> #define flush_pmd_tlb_range(vma, addr, end) BUILD_BUG()
>> #define flush_pud_tlb_range(vma, addr, end) BUILD_BUG()
>> +#define flush_p4d_tlb_range(vma, addr, end) BUILD_BUG()
>> #endif
>> #endif
>
> Ideally you'd make __HAVE_ARCH_FLUSH_PMD_TLB_RANGE go away. Power
> certainly doesnt need it with the below.
>
However, arch `arc` also uses __HAVE_ARCH_FLUSH_PMD_TLB_RANGE :
grep -nr __HAVE_ARCH_FLUSH_PMD_TLB_RANGE
mm/pgtable-generic.c:104:#ifndef __HAVE_ARCH_FLUSH_PMD_TLB_RANGE
mm/pgtable-generic.c:152:#endif /* __HAVE_ARCH_FLUSH_PMD_TLB_RANGE */
include/asm-generic/pgtable.h:1153:#ifndef __HAVE_ARCH_FLUSH_PMD_TLB_RANGE
arch/powerpc/include/asm/book3s/64/tlbflush.h:49:#define __HAVE_ARCH_FLUSH_PMD_TLB_RANGE
arch/arc/include/asm/hugepage.h:69:#define __HAVE_ARCH_FLUSH_PMD_TLB_RANGE
So I am not sure if we can remove it.
And if we remove the __HAVE_ARCH_FLUSH_PMD_TLB_RANGE, how to ensure not
redefine flush_pXX_tlb_range() ?
>> diff --git a/mm/pgtable-generic.c b/mm/pgtable-generic.c
>> index 3d7c01e76efc..0f5414a4a2ec 100644
>> --- a/mm/pgtable-generic.c
>> +++ b/mm/pgtable-generic.c
>> @@ -101,6 +101,56 @@ pte_t ptep_clear_flush(struct vm_area_struct *vma, unsigned long address,
>>
>> #ifdef CONFIG_TRANSPARENT_HUGEPAGE
>>
>> +#ifndef __HAVE_ARCH_FLUSH_PMD_TLB_RANGE
>> +void flush_pte_tlb_range(struct vm_area_struct *vma,
>> + unsigned long addr, unsigned long end)
>> +{
>> + struct mmu_gather tlb;
>> +
>> + tlb_gather_mmu(&tlb, vma->vm_mm, addr, end);
>> + tlb_start_vma(&tlb, vma);
>> + tlb_set_pte_range(&tlb, addr, end - addr);
>> + tlb_end_vma(&tlb, vma);
>> + tlb_finish_mmu(&tlb, addr, end);
>> +}
>> +
>> +void flush_pmd_tlb_range(struct vm_area_struct *vma,
>> + unsigned long addr, unsigned long end)
>> +{
>> + struct mmu_gather tlb;
>> +
>> + tlb_gather_mmu(&tlb, vma->vm_mm, addr, end);
>> + tlb_start_vma(&tlb, vma);
>> + tlb_set_pmd_range(&tlb, addr, end - addr);
>> + tlb_end_vma(&tlb, vma);
>> + tlb_finish_mmu(&tlb, addr, end);
>> +}
>> +
>> +void flush_pud_tlb_range(struct vm_area_struct *vma,
>> + unsigned long addr, unsigned long end)
>> +{
>> + struct mmu_gather tlb;
>> +
>> + tlb_gather_mmu(&tlb, vma->vm_mm, addr, end);
>> + tlb_start_vma(&tlb, vma);
>> + tlb_set_pud_range(&tlb, addr, end - addr);
>> + tlb_end_vma(&tlb, vma);
>> + tlb_finish_mmu(&tlb, addr, end);
>> +}
>> +
>> +void flush_p4d_tlb_range(struct vm_area_struct *vma,
>> + unsigned long addr, unsigned long end)
>> +{
>> + struct mmu_gather tlb;
>> +
>> + tlb_gather_mmu(&tlb, vma->vm_mm, addr, end);
>> + tlb_start_vma(&tlb, vma);
>> + tlb_set_p4d_range(&tlb, addr, end - addr);
>> + tlb_end_vma(&tlb, vma);
>> + tlb_finish_mmu(&tlb, addr, end);
>> +}
>> +#endif /* __HAVE_ARCH_FLUSH_PMD_TLB_RANGE */
>
> You're nowhere near lazy enough:
>
> #define FLUSH_Pxx_TLB_RANGE(_pxx) \
> void flush_##_pxx##_tlb_range(struct vm_area_struct *vma, \
> unsigned long addr, unsigned long end) \
> { \
> struct mmu_gather tlb; \
> \
> tlb_gather_mmu(&tlb, vma->vm_mm, addr, end); \
> tlb_start_vma(&tlb, vma); \
> tlb_flush_##_pxx##_range(&tlb, addr, end-addr); \
> tlb_end_vma(&tlb, vma); \
> tlb_finish_mmu(&tlb, addr, end); \
> }
>
> FLUSH_Pxx_TLB_RANGE(pte)
> FLUSH_Pxx_TLB_RANGE(pmd)
> FLUSH_Pxx_TLB_RANGE(pud)
> FLUSH_Pxx_TLB_RANGE(p4d)
>
>
> .
>
next prev parent reply other threads:[~2020-04-21 14:19 UTC|newest]
Thread overview: 18+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-04-03 9:00 [PATCH v1 0/6] arm64: tlb: add support for TTL feature Zhenyu Ye
2020-04-03 9:00 ` [PATCH v1 1/6] arm64: Detect the ARMv8.4 " Zhenyu Ye
2020-04-21 16:53 ` Christoph Hellwig
2020-04-21 17:13 ` Peter Zijlstra
2020-04-21 17:16 ` Christoph Hellwig
2020-04-22 2:13 ` Zhenyu Ye
2020-04-03 9:00 ` [PATCH v1 2/6] arm64: Add level-hinted TLB invalidation helper Zhenyu Ye
2020-04-03 9:00 ` [PATCH v1 3/6] arm64: Add tlbi_user_level " Zhenyu Ye
2020-04-03 9:00 ` [PATCH v1 4/6] tlb: mmu_gather: add tlb_set_*_range APIs Zhenyu Ye
2020-04-20 11:46 ` Peter Zijlstra
2020-04-03 9:00 ` [PATCH v1 5/6] mm: tlb: Provide flush_*_tlb_range wrappers Zhenyu Ye
2020-04-20 12:09 ` Peter Zijlstra
2020-04-21 14:18 ` Zhenyu Ye [this message]
2020-04-03 9:00 ` [PATCH v1 6/6] arm64: tlb: Set the TTL field in flush_tlb_range Zhenyu Ye
2020-04-20 12:10 ` Peter Zijlstra
2020-04-21 0:06 ` Steven Rostedt
2020-04-21 8:30 ` Peter Zijlstra
2020-04-21 12:22 ` Zhenyu Ye
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=8f6e877c-1462-441b-23ec-2a6bd3308099@huawei.com \
--to=yezhenyu2@huawei.com \
--cc=Dave.Martin@arm.com \
--cc=akpm@linux-foundation.org \
--cc=aneesh.kumar@linux.ibm.com \
--cc=arm@kernel.org \
--cc=arnd@arndb.de \
--cc=broonie@kernel.org \
--cc=catalin.marinas@arm.com \
--cc=guohanjun@huawei.com \
--cc=kuhn.chenqun@huawei.com \
--cc=linux-arch@vger.kernel.org \
--cc=linux-arm-kernel@lists.infradead.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-mm@kvack.org \
--cc=mark.rutland@arm.com \
--cc=maz@kernel.org \
--cc=npiggin@gmail.com \
--cc=peterz@infradead.org \
--cc=prime.zeng@hisilicon.com \
--cc=rostedt@goodmis.org \
--cc=steven.price@arm.com \
--cc=suzuki.poulose@arm.com \
--cc=tglx@linutronix.de \
--cc=will@kernel.org \
--cc=xiexiangyou@huawei.com \
--cc=yuzhao@google.com \
--cc=zhangshaokun@hisilicon.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).