From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pg0-f70.google.com (mail-pg0-f70.google.com [74.125.83.70]) by kanga.kvack.org (Postfix) with ESMTP id 109CD6B0292 for ; Mon, 5 Jun 2017 04:12:01 -0400 (EDT) Received: by mail-pg0-f70.google.com with SMTP id t126so66417117pgc.9 for ; Mon, 05 Jun 2017 01:12:01 -0700 (PDT) Received: from szxga01-in.huawei.com (szxga01-in.huawei.com. [45.249.212.187]) by mx.google.com with ESMTPS id g125si30233940pfc.376.2017.06.05.01.11.59 for (version=TLS1 cipher=AES128-SHA bits=128/128); Mon, 05 Jun 2017 01:12:00 -0700 (PDT) From: Yisheng Xie Subject: [PATCH v2] vmalloc: show more detail info in vmallocinfo for clarify Date: Mon, 5 Jun 2017 16:01:22 +0800 Message-ID: <1496649682-20710-1-git-send-email-xieyisheng1@huawei.com> MIME-Version: 1.0 Content-Type: text/plain Sender: owner-linux-mm@kvack.org List-ID: To: akpm@linux-foundation.org Cc: mhocko@suse.com, zijun_hu@htc.com, mingo@kernel.org, thgarnie@google.com, kirill.shutemov@linux.intel.com, aryabinin@virtuozzo.com, chris@chris-wilson.co.uk, tim.c.chen@linux.intel.com, linux-mm@kvack.org, linux-kernel@vger.kernel.org, guohanjun@huawei.com When ioremap a 67112960 bytes vm_area with the vmallocinfo: [..] 0xec79b000-0xec7fa000 389120 ftl_add_mtd+0x4d0/0x754 pages=94 vmalloc 0xec800000-0xecbe1000 4067328 kbox_proc_mem_write+0x104/0x1c4 phys=8b520000 ioremap we get the result: 0xf1000000-0xf5001000 67112960 devm_ioremap+0x38/0x7c phys=40000000 ioremap For the align for ioremap must be less than '1 << IOREMAP_MAX_ORDER': if (flags & VM_IOREMAP) align = 1ul << clamp_t(int, get_count_order_long(size), PAGE_SHIFT, IOREMAP_MAX_ORDER); So it makes idiot like me a litter puzzle why jump the vm_area from 0xec800000-0xecbe1000 to 0xf1000000-0xf5001000, and leave 0xed000000-0xf1000000 as a big hole. This is to show all of vm_area, including which is freeing but still in vmap_area_list, to make it more clear about why we will get 0xf1000000-0xf5001000 int the above case. And we will get the vmallocinfo like: [..] 0xec79b000-0xec7fa000 389120 ftl_add_mtd+0x4d0/0x754 pages=94 vmalloc 0xec800000-0xecbe1000 4067328 kbox_proc_mem_write+0x104/0x1c4 phys=8b520000 ioremap [..] 0xece7c000-0xece7e000 8192 unpurged vm_area 0xece7e000-0xece83000 20480 vm_map_ram 0xf0099000-0xf00aa000 69632 vm_map_ram after apply this patch. Signed-off-by: Yisheng Xie --- v2: - changed "freeing vm_area" to "unpurged vm_area" to be clearer - Tim mm/vmalloc.c | 10 +++++++++- 1 file changed, 9 insertions(+), 1 deletion(-) diff --git a/mm/vmalloc.c b/mm/vmalloc.c index 34a1c3e..6ef021f 100644 --- a/mm/vmalloc.c +++ b/mm/vmalloc.c @@ -314,6 +314,7 @@ unsigned long vmalloc_to_pfn(const void *vmalloc_addr) /*** Global kva allocator ***/ +#define VM_LAZY_FREE 0x02 #define VM_VM_AREA 0x04 static DEFINE_SPINLOCK(vmap_area_lock); @@ -1486,6 +1487,7 @@ struct vm_struct *remove_vm_area(const void *addr) spin_lock(&vmap_area_lock); va->vm = NULL; va->flags &= ~VM_VM_AREA; + va->flags |= VM_LAZY_FREE; spin_unlock(&vmap_area_lock); vmap_debug_free_range(va->va_start, va->va_end); @@ -2698,8 +2700,14 @@ static int s_show(struct seq_file *m, void *p) * s_show can encounter race with remove_vm_area, !VM_VM_AREA on * behalf of vmap area is being tear down or vm_map_ram allocation. */ - if (!(va->flags & VM_VM_AREA)) + if (!(va->flags & VM_VM_AREA)) { + seq_printf(m, "0x%pK-0x%pK %7ld %s\n", + (void *)va->va_start, (void *)va->va_end, + va->va_end - va->va_start, + va->flags & VM_LAZY_FREE ? "unpurged vm_area" : "vm_map_ram"); + return 0; + } v = va->vm; -- 1.7.12.4 -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org