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charset=UTF-8 Content-Transfer-Encoding: 7bit X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.9.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20260629_074717_701839_132709CF X-CRM114-Status: GOOD ( 20.66 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On 18/06/26 2:17 pm, Wen Jiang wrote: > From: "Barry Song (Xiaomi)" > > Try to align the vmap virtual address to PMD_SHIFT or a > larger PTE mapping size hinted by the architecture, so > contiguous pages can be batch-mapped when setting PMD or > PTE entries. > > Add __get_vm_area_node_aligned_caller() as a wrapper over > __get_vm_area_node() to simplify repeated calls with fixed > arguments. > > Signed-off-by: Barry Song (Xiaomi) > Signed-off-by: Wen Jiang > Tested-by: Xueyuan Chen > --- > mm/vmalloc.c | 37 ++++++++++++++++++++++++++++++++++++- > 1 file changed, 36 insertions(+), 1 deletion(-) > > diff --git a/mm/vmalloc.c b/mm/vmalloc.c > index fffb885cb2158..bc9fa93e2bdc6 100644 > --- a/mm/vmalloc.c > +++ b/mm/vmalloc.c > @@ -3628,6 +3628,41 @@ static int vmap_batched(unsigned long addr, unsigned long end, > return err; > } > > +static struct vm_struct *__get_vm_area_node_aligned_caller(unsigned long size, > + unsigned long align, unsigned long flags, const void *caller) There are 3 similar functions below __get_vm_area_node: they are __get_vm_area_caller, get_vm_area and get_vm_area_caller. You can put this one just below them. > +{ > + return __get_vm_area_node(size, align, PAGE_SHIFT, flags, > + VMALLOC_START, VMALLOC_END, > + NUMA_NO_NODE, GFP_KERNEL, caller); > +} > + > +static struct vm_struct *vmap_get_aligned_vm_area(unsigned long size, > + unsigned long flags, const void *caller) > +{ > + struct vm_struct *vm_area; > + unsigned int shift; > + > + /* Try PMD alignment for large sizes */ This comment feels excessive. Can remove it. > + if (size >= PMD_SIZE) { Need an arch_vmap_pmd_supported() check here. > + vm_area = __get_vm_area_node_aligned_caller(size, PMD_SIZE, > + flags, caller); > + if (vm_area) > + return vm_area; > + } > + > + /* Try CONT_PTE alignment */ Comment feels excessive, and again no need to mention arm64 specific stuff here. Just remove it. > + shift = arch_vmap_pte_supported_shift(size); > + if (shift > PAGE_SHIFT) { > + vm_area = __get_vm_area_node_aligned_caller(size, 1UL << shift, > + flags, caller); > + if (vm_area) > + return vm_area; > + } > + > + /* Fall back to page alignment */ This comment can also be dropped, but I am fine either way. > + return __get_vm_area_node_aligned_caller(size, PAGE_SIZE, flags, caller); > +} > + > /** > * vmap - map an array of pages into virtually contiguous space > * @pages: array of page pointers > @@ -3666,7 +3701,7 @@ void *vmap(struct page **pages, unsigned int count, > return NULL; > > size = (unsigned long)count << PAGE_SHIFT; > - area = get_vm_area_caller(size, flags, __builtin_return_address(0)); > + area = vmap_get_aligned_vm_area(size, flags, __builtin_return_address(0)); So the effect is that now we search for an aligned vm_struct unconditionally. Better to mention in the commit message that we do not expect any significant overhead for this. > if (!area) > return NULL; >