From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 7E86D31F984; Mon, 27 Apr 2026 20:25:19 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1777321519; cv=none; b=AWQnfde00u4jDVsrsw8Vr7fKGJDO/wK3y/C/Rairmu1pHUZo03pvubP8f+lTcO1TQbtFmlH5+eU0nceS4rav2wT7KS94DFwuVCneSe/pEFws/Qjw4f6L87ookKtQ2y+oYMCyCrU6kBVaxGB6pbgpDC7lwUT46y3lDfH2ADEDL0Y= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1777321519; c=relaxed/simple; bh=wZ62JJbJbBFYxmz4nXsEdURZ9ZvZQcCgwl8lIq3rVHI=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=VqrEqID2SEVW9OxSwqgWrSIfmMfPw6j/lDtycnYBfUCfhMttTwySbZIcffxwq10b5TryHZSocT56g9vlxIuw6/s8pHP8OR8nIS1QY5VV6et6Ibn/9iB9rB8dTTQAcfMHBMHj1lkgV/oc0gXyO3xMkzfk1sjBGwMZG/nfshMuHQI= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=gkxKUB71; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="gkxKUB71" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 3AF12C19425; Mon, 27 Apr 2026 20:25:02 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1777321519; bh=wZ62JJbJbBFYxmz4nXsEdURZ9ZvZQcCgwl8lIq3rVHI=; h=Date:Subject:To:Cc:References:From:In-Reply-To:From; b=gkxKUB71RDl0C8Txlx3EhD82nFBtJoCkuZlpTFV1lUNcqsSh8sMHSpg9Gd2zDckOX d57E0mKovidPdCFENazaUlbeAwBZzgv6VWMK4AyLbVsRZ31Ky1K0r1lo8HN83yFxFP i5YUdGj4UPCvbyv14v45UZO72SJn+Tq40WipfZVuxjJbQ/X0vysEoxqBKYqq9rBuDN jvpMIXGkqcYdvy9jGQ7rpQWMfjUc4Dsd8Wm6tHbTfcBWjXy/IDMCDd4wOFM2/1RUnU HbYmg7WocFt5sWdAoDVRF9or3z5fNBwhHIBblyV35zwihyDmmm1YU9+O2iFTbzliLT zlb7HcaNpqRUQ== Message-ID: <5564e170-d052-4445-9914-70bfd852d3b1@kernel.org> Date: Mon, 27 Apr 2026 22:24:59 +0200 Precedence: bulk X-Mailing-List: linux-trace-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH 7.2 v16 09/13] mm/khugepaged: introduce collapse_allowable_orders helper function To: Nico Pache , linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, linux-trace-kernel@vger.kernel.org Cc: aarcange@redhat.com, akpm@linux-foundation.org, anshuman.khandual@arm.com, apopple@nvidia.com, baohua@kernel.org, baolin.wang@linux.alibaba.com, byungchul@sk.com, catalin.marinas@arm.com, cl@gentwo.org, corbet@lwn.net, dave.hansen@linux.intel.com, dev.jain@arm.com, gourry@gourry.net, hannes@cmpxchg.org, hughd@google.com, jack@suse.cz, jackmanb@google.com, jannh@google.com, jglisse@google.com, joshua.hahnjy@gmail.com, kas@kernel.org, lance.yang@linux.dev, Liam.Howlett@oracle.com, ljs@kernel.org, mathieu.desnoyers@efficios.com, matthew.brost@intel.com, mhiramat@kernel.org, mhocko@suse.com, peterx@redhat.com, pfalcato@suse.de, rakie.kim@sk.com, raquini@redhat.com, rdunlap@infradead.org, richard.weiyang@gmail.com, rientjes@google.com, rostedt@goodmis.org, rppt@kernel.org, ryan.roberts@arm.com, shivankg@amd.com, sunnanyong@huawei.com, surenb@google.com, thomas.hellstrom@linux.intel.com, tiwai@suse.de, usamaarif642@gmail.com, vbabka@suse.cz, vishal.moola@gmail.com, wangkefeng.wang@huawei.com, will@kernel.org, willy@infradead.org, yang@os.amperecomputing.com, ying.huang@linux.alibaba.com, ziy@nvidia.com, zokeefe@google.com References: <20260419185750.260784-1-npache@redhat.com> <20260419185750.260784-10-npache@redhat.com> From: "David Hildenbrand (Arm)" Content-Language: en-US Autocrypt: addr=david@kernel.org; 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charset=UTF-8 Content-Transfer-Encoding: 7bit On 4/19/26 20:57, Nico Pache wrote: > Add collapse_allowable_orders() to generalize THP order eligibility. The > function determines which THP orders are permitted based on collapse > context (khugepaged vs madv_collapse). > > This consolidates collapse configuration logic and provides a clean > interface for future mTHP collapse support where the orders may be > different. > > Reviewed-by: Baolin Wang > Signed-off-by: Nico Pache > --- [...] > cc = kmalloc_obj(*cc); > diff --git a/mm/vma.c b/mm/vma.c > index 377321b48734..c0398fb597b3 100644 > --- a/mm/vma.c > +++ b/mm/vma.c > @@ -989,7 +989,7 @@ static __must_check struct vm_area_struct *vma_merge_existing_range( > goto abort; > > vma_set_flags_mask(vmg->target, sticky_flags); > - khugepaged_enter_vma(vmg->target, vmg->vm_flags); > + khugepaged_enter_vma(vmg->target); > vmg->state = VMA_MERGE_SUCCESS; > return vmg->target; > > @@ -1110,7 +1110,7 @@ struct vm_area_struct *vma_merge_new_range(struct vma_merge_struct *vmg) > * following VMA if we have VMAs on both sides. > */ > if (vmg->target && !vma_expand(vmg)) { > - khugepaged_enter_vma(vmg->target, vmg->vm_flags); > + khugepaged_enter_vma(vmg->target); > vmg->state = VMA_MERGE_SUCCESS; > return vmg->target; > } > @@ -2589,7 +2589,7 @@ static int __mmap_new_vma(struct mmap_state *map, struct vm_area_struct **vmap, > * call covers the non-merge case. > */ > if (!vma_is_anonymous(vma)) > - khugepaged_enter_vma(vma, map->vm_flags); > + khugepaged_enter_vma(vma); > *vmap = vma; Are you sure that in all cases, vma->vm_flags already corresponds to vmg->vm_flags / map->vm_flags? That's a change that makes this patch unnecessary hard to follow, in particular, because it's not documented in the patch description. If you think the change is fine, you should better move that into a separate cleanup patch where you only drop the flags parameter from khugepaged_enter_vma(). -- Cheers, David