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Howlett" , Lorenzo Stoakes , Madhavan Srinivasan , Michael Ellerman , Michal Hocko , Mike Rapoport , Nicholas Piggin , Peter Zijlstra , Ryan Roberts , Suren Baghdasaryan , Thomas Gleixner , Vlastimil Babka , Will Deacon , Yeoreum Yun , linux-arm-kernel@lists.infradead.org, linuxppc-dev@lists.ozlabs.org, sparclinux@vger.kernel.org, xen-devel@lists.xenproject.org, x86@kernel.org References: <20251029100909.3381140-1-kevin.brodsky@arm.com> <20251029100909.3381140-3-kevin.brodsky@arm.com> From: David Hildenbrand Autocrypt: addr=david@redhat.com; keydata= xsFNBFXLn5EBEAC+zYvAFJxCBY9Tr1xZgcESmxVNI/0ffzE/ZQOiHJl6mGkmA1R7/uUpiCjJ dBrn+lhhOYjjNefFQou6478faXE6o2AhmebqT4KiQoUQFV4R7y1KMEKoSyy8hQaK1umALTdL QZLQMzNE74ap+GDK0wnacPQFpcG1AE9RMq3aeErY5tujekBS32jfC/7AnH7I0v1v1TbbK3Gp XNeiN4QroO+5qaSr0ID2sz5jtBLRb15RMre27E1ImpaIv2Jw8NJgW0k/D1RyKCwaTsgRdwuK Kx/Y91XuSBdz0uOyU/S8kM1+ag0wvsGlpBVxRR/xw/E8M7TEwuCZQArqqTCmkG6HGcXFT0V9 PXFNNgV5jXMQRwU0O/ztJIQqsE5LsUomE//bLwzj9IVsaQpKDqW6TAPjcdBDPLHvriq7kGjt WhVhdl0qEYB8lkBEU7V2Yb+SYhmhpDrti9Fq1EsmhiHSkxJcGREoMK/63r9WLZYI3+4W2rAc UucZa4OT27U5ZISjNg3Ev0rxU5UH2/pT4wJCfxwocmqaRr6UYmrtZmND89X0KigoFD/XSeVv jwBRNjPAubK9/k5NoRrYqztM9W6sJqrH8+UWZ1Idd/DdmogJh0gNC0+N42Za9yBRURfIdKSb B3JfpUqcWwE7vUaYrHG1nw54pLUoPG6sAA7Mehl3nd4pZUALHwARAQABzSREYXZpZCBIaWxk ZW5icmFuZCA8ZGF2aWRAcmVkaGF0LmNvbT7CwZoEEwEIAEQCGwMCF4ACGQEFCwkIBwICIgIG FQoJCAsCBBYCAwECHgcWIQQb2cqtc1xMOkYN/MpN3hD3AP+DWgUCaJzangUJJlgIpAAKCRBN 3hD3AP+DWhAxD/9wcL0A+2rtaAmutaKTfxhTP0b4AAp1r/eLxjrbfbCCmh4pqzBhmSX/4z11 opn2KqcOsueRF1t2ENLOWzQu3Roiny2HOU7DajqB4dm1BVMaXQya5ae2ghzlJN9SIoopTWlR 0Af3hPj5E2PYvQhlcqeoehKlBo9rROJv/rjmr2x0yOM8qeTroH/ZzNlCtJ56AsE6Tvl+r7cW 3x7/Jq5WvWeudKrhFh7/yQ7eRvHCjd9bBrZTlgAfiHmX9AnCCPRPpNGNedV9Yty2Jnxhfmbv Pw37LA/jef8zlCDyUh2KCU1xVEOWqg15o1RtTyGV1nXV2O/mfuQJud5vIgzBvHhypc3p6VZJ lEf8YmT+Ol5P7SfCs5/uGdWUYQEMqOlg6w9R4Pe8d+mk8KGvfE9/zTwGg0nRgKqlQXrWRERv cuEwQbridlPAoQHrFWtwpgYMXx2TaZ3sihcIPo9uU5eBs0rf4mOERY75SK+Ekayv2ucTfjxr Kf014py2aoRJHuvy85ee/zIyLmve5hngZTTe3Wg3TInT9UTFzTPhItam6dZ1xqdTGHZYGU0O otRHcwLGt470grdiob6PfVTXoHlBvkWRadMhSuG4RORCDpq89vu5QralFNIf3EysNohoFy2A LYg2/D53xbU/aa4DDzBb5b1Rkg/udO1gZocVQWrDh6I2K3+cCs7BTQRVy5+RARAA59fefSDR 9nMGCb9LbMX+TFAoIQo/wgP5XPyzLYakO+94GrgfZjfhdaxPXMsl2+o8jhp/hlIzG56taNdt VZtPp3ih1AgbR8rHgXw1xwOpuAd5lE1qNd54ndHuADO9a9A0vPimIes78Hi1/yy+ZEEvRkHk /kDa6F3AtTc1m4rbbOk2fiKzzsE9YXweFjQvl9p+AMw6qd/iC4lUk9g0+FQXNdRs+o4o6Qvy iOQJfGQ4UcBuOy1IrkJrd8qq5jet1fcM2j4QvsW8CLDWZS1L7kZ5gT5EycMKxUWb8LuRjxzZ 3QY1aQH2kkzn6acigU3HLtgFyV1gBNV44ehjgvJpRY2cC8VhanTx0dZ9mj1YKIky5N+C0f21 zvntBqcxV0+3p8MrxRRcgEtDZNav+xAoT3G0W4SahAaUTWXpsZoOecwtxi74CyneQNPTDjNg azHmvpdBVEfj7k3p4dmJp5i0U66Onmf6mMFpArvBRSMOKU9DlAzMi4IvhiNWjKVaIE2Se9BY FdKVAJaZq85P2y20ZBd08ILnKcj7XKZkLU5FkoA0udEBvQ0f9QLNyyy3DZMCQWcwRuj1m73D sq8DEFBdZ5eEkj1dCyx+t/ga6x2rHyc8Sl86oK1tvAkwBNsfKou3v+jP/l14a7DGBvrmlYjO 59o3t6inu6H7pt7OL6u6BQj7DoMAEQEAAcLBfAQYAQgAJgIbDBYhBBvZyq1zXEw6Rg38yk3e EPcA/4NaBQJonNqrBQkmWAihAAoJEE3eEPcA/4NaKtMQALAJ8PzprBEXbXcEXwDKQu+P/vts IfUb1UNMfMV76BicGa5NCZnJNQASDP/+bFg6O3gx5NbhHHPeaWz/VxlOmYHokHodOvtL0WCC 8A5PEP8tOk6029Z+J+xUcMrJClNVFpzVvOpb1lCbhjwAV465Hy+NUSbbUiRxdzNQtLtgZzOV Zw7jxUCs4UUZLQTCuBpFgb15bBxYZ/BL9MbzxPxvfUQIPbnzQMcqtpUs21CMK2PdfCh5c4gS sDci6D5/ZIBw94UQWmGpM/O1ilGXde2ZzzGYl64glmccD8e87OnEgKnH3FbnJnT4iJchtSvx yJNi1+t0+qDti4m88+/9IuPqCKb6Stl+s2dnLtJNrjXBGJtsQG/sRpqsJz5x1/2nPJSRMsx9 5YfqbdrJSOFXDzZ8/r82HgQEtUvlSXNaXCa95ez0UkOG7+bDm2b3s0XahBQeLVCH0mw3RAQg r7xDAYKIrAwfHHmMTnBQDPJwVqxJjVNr7yBic4yfzVWGCGNE4DnOW0vcIeoyhy9vnIa3w1uZ 3iyY2Nsd7JxfKu1PRhCGwXzRw5TlfEsoRI7V9A8isUCoqE2Dzh3FvYHVeX4Us+bRL/oqareJ CIFqgYMyvHj7Q06kTKmauOe4Nf0l0qEkIuIzfoLJ3qr5UyXc2hLtWyT9Ir+lYlX9efqh7mOY qIws/H2t In-Reply-To: <20251029100909.3381140-3-kevin.brodsky@arm.com> X-Mimecast-Spam-Score: 0 X-Mimecast-MFC-PROC-ID: OglFlhDm5TdqVOO1H_kd8abV9trEVaN1sDz-bDluEmE_1761999265 X-Mimecast-Originator: redhat.com Content-Language: en-US Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-Rspam-User: X-Rspamd-Server: rspam04 X-Rspamd-Queue-Id: 9F69040009 X-Stat-Signature: aa9kpf3ocufhifgygkg8cii5jzo8kwce X-HE-Tag: 1761999268-930560 X-HE-Meta: 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 219OxirQ 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 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On 29.10.25 11:08, Kevin Brodsky wrote: > arch_flush_lazy_mmu_mode() is called when outstanding batched > pgtable operations must be completed immediately. There should > however be no need to leave and re-enter lazy MMU completely. The > only part of that sequence that we really need is xen_mc_flush(); > call it directly. > > Signed-off-by: Kevin Brodsky > --- > arch/x86/xen/mmu_pv.c | 6 ++---- > 1 file changed, 2 insertions(+), 4 deletions(-) > > diff --git a/arch/x86/xen/mmu_pv.c b/arch/x86/xen/mmu_pv.c > index 2a4a8deaf612..7a35c3393df4 100644 > --- a/arch/x86/xen/mmu_pv.c > +++ b/arch/x86/xen/mmu_pv.c > @@ -2139,10 +2139,8 @@ static void xen_flush_lazy_mmu(void) > { > preempt_disable(); > > - if (xen_get_lazy_mode() == XEN_LAZY_MMU) { > - arch_leave_lazy_mmu_mode(); > - arch_enter_lazy_mmu_mode(); > - } > + if (xen_get_lazy_mode() == XEN_LAZY_MMU) > + xen_mc_flush(); > > preempt_enable(); > } Looks like that was moved to XEN code in commit a4a7644c15096f57f92252dd6e1046bf269c87d8 Author: Juergen Gross Date: Wed Sep 13 13:38:27 2023 +0200 x86/xen: move paravirt lazy code And essentially the previous implementation lived in arch/x86/kernel/paravirt.c:paravirt_flush_lazy_mmu(void) in an implementation-agnostic way: void paravirt_flush_lazy_mmu(void) { preempt_disable(); if (paravirt_get_lazy_mode() == PARAVIRT_LAZY_MMU) { arch_leave_lazy_mmu_mode(); arch_enter_lazy_mmu_mode(); } preempt_enable(); } So indeed, I assume just doing the flush here is sufficient. Reviewed-by: David Hildenbrand -- Cheers David / dhildenb