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charset=us-ascii Content-Disposition: inline In-Reply-To: <20260408025115.27368-5-baohua@kernel.org> 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 Wed, Apr 08, 2026 at 10:51:11AM +0800, Barry Song (Xiaomi) wrote: > For vmalloc() allocations with VM_ALLOW_HUGE_VMAP, we no longer > need to iterate over pages one by one, which would otherwise lead to > zigzag page table mappings. > > The code is now unified with the PAGE_SHIFT case by simply > calling vmap_small_pages_range_noflush(). > > Signed-off-by: Barry Song (Xiaomi) > --- > mm/vmalloc.c | 22 ++++------------------ > 1 file changed, 4 insertions(+), 18 deletions(-) > > diff --git a/mm/vmalloc.c b/mm/vmalloc.c > index 5bf072297536..eba436386929 100644 > --- a/mm/vmalloc.c > +++ b/mm/vmalloc.c > @@ -689,27 +689,13 @@ static int vmap_small_pages_range_noflush(unsigned long addr, unsigned long end, > int __vmap_pages_range_noflush(unsigned long addr, unsigned long end, > pgprot_t prot, struct page **pages, unsigned int page_shift) > { > - unsigned int i, nr = (end - addr) >> PAGE_SHIFT; > - > WARN_ON(page_shift < PAGE_SHIFT); > > - if (!IS_ENABLED(CONFIG_HAVE_ARCH_HUGE_VMALLOC) || > - page_shift == PAGE_SHIFT) > - return vmap_small_pages_range_noflush(addr, end, prot, pages, PAGE_SHIFT); > - > - for (i = 0; i < nr; i += 1U << (page_shift - PAGE_SHIFT)) { > - int err; > - > - err = vmap_range_noflush(addr, addr + (1UL << page_shift), > - page_to_phys(pages[i]), prot, > - page_shift); > - if (err) > - return err; > + if (!IS_ENABLED(CONFIG_HAVE_ARCH_HUGE_VMALLOC)) > + page_shift = PAGE_SHIFT; > > - addr += 1UL << page_shift; > - } > - > - return 0; > + return vmap_small_pages_range_noflush(addr, end, prot, pages, > + min(page_shift, PMD_SHIFT)); Wouldn't vmap_range_noflush() already "do the right thing" even without changes to vmap_small_pages_range_noflush()? > } > > int vmap_pages_range_noflush(unsigned long addr, unsigned long end, > -- > 2.39.3 (Apple Git-146) > -- Sincerely yours, Mike.