[PATCH] Frontswap: fix the condition in BUG_ON

>From 012a564c7210346b99d12e3d2485542bb090586e Mon Sep 17 00:00:00 2001 From: Haifeng Li Date: Fri, 31 Oct 2014 17:40:44 +0800 Subject: [PATCH] Frontswap: fix the condition in BUG_ON The largest index of swap device is MAX_SWAPFILES-1. So the type should be less than MAX_SWAPFILES. Signed-off-by

Re: Kexec couldn't reboot capture kernel on pandaboard ES with OMAP4460

2013/4/10 Stephen Warren : > On 04/10/2013 03:35 AM, Li Haifeng wrote: >> Hi, everyone. >> >> Recently, I try to run kdump on pandaboard ES with omap4460. After >> load capture kernel by "kexec -l" and execute "kexec -e", the serial >> port ou

Re: Should a swapped out page be deleted from swap cache?

2013/2/20 Ric Mason : > > Hi Hugh, > > > On 02/20/2013 02:56 AM, Hugh Dickins wrote: >> >> On Tue, 19 Feb 2013, Ric Mason wrote: >>> >>> There is a call of try_to_free_swap in function swap_writepage, if >>> swap_writepage is call from shrink_page_list path, PageSwapCache(page) == >>> trure, PageWr

Re: [PATCH] mm: Fixup the condition whether the page cache is free

Thanks very much for you explanation. :-) 2013/3/4 Johannes Weiner : > On Mon, Mar 04, 2013 at 09:54:26AM +0800, Li Haifeng wrote: >> When a page cache is to reclaim, we should to decide whether the page >> cache is free. >> IMO, the condition whether a page cache is fre

[PATCH] mm: Fixup the condition whether the page cache is free

When a page cache is to reclaim, we should to decide whether the page cache is free. IMO, the condition whether a page cache is free should be 3 in page frame reclaiming. The reason lists as below. When page is allocated, the page->_count is 1(code fragment is code-1 ). And when the page is alloca

Re: A noobish question on mm

2013/2/19 Soham Chakraborty : > > > On Tue, Feb 19, 2013 at 12:08 PM, Li Haifeng wrote: >> >> 2013/2/19 Soham Chakraborty : >> > Hey dude, >> > >> > Apologies for this kind of approach but I was not sure whether I can >> > directly mail

Re: Should a swapped out page be deleted from swap cache?

2013/2/19 Will Huck : > On 02/19/2013 10:04 AM, Li Haifeng wrote: >> >> 2013/2/19 Hugh Dickins >>> >>> On Mon, 18 Feb 2013, Li Haifeng wrote: >>> >>>> For explain my question, the two points should be displayed as below. >>>> >&

Re: A noobish question on mm

2013/2/19 Soham Chakraborty : > Hey dude, > > Apologies for this kind of approach but I was not sure whether I can > directly mail the list with such a noobish question. I have been poking > around in mm subsystem for around 2 years now and I have never got a fine, > bullet proof answer to this que

Re: Should a swapped out page be deleted from swap cache?

2013/2/19 Hugh Dickins > > On Mon, 18 Feb 2013, Li Haifeng wrote: > > > For explain my question, the two points should be displayed as below. > > > > 1. If an anonymous page is swapped out, this page will be deleted > > from swap cache and be put back into buddy

Qestion about page->_count and page reclaim

Hi, all in kernel. The page->_count is the page frame's usage count. When page is allocated, the page->_cout will be set 1. After be allocated from buddy system, the page will be used by process. get_page and put_page/put_page_testzero will used in pairs. is it right? When the page is reclaimed

[PATCH 2/2] mm: Fixup abandoned PG_buddy for private in struct page

PG_buddy, an abandoned flag, indicates page(s) is/are free and in buddy allocator. And when page(s) in buddy allocator, the _mapcount will equal PAGE_BUDDY_MAPCOUNT_VALUE. So, here, "_mapcount equals PAGE_BUDDY_MAPCOUNT_VALUE" instead of "PG_buddy is set". Signed-off-by: Haifeng Li --- include/l

[PATCH 1/2] mm: Fixup obsolete PG_buddy flag in error_states[]

PG_buddy, an abandoned flag, indicates page(s) is/are free and in buddy allocator. So in the comment, "pages in buddy system" instead of "PG_buddy pages". Signed-off-by: Haifeng Li --- mm/memory-failure.c |3 ++- 1 files changed, 2 insertions(+), 1 deletions(-) diff --git a/mm/memory-failur

Re: Fixup the page of buddy_higher address's calculation

2012/8/24 Michal Hocko : > On Fri 24-08-12 10:08:20, Li Haifeng wrote: > [...] >> Subject: [PATCH] Fix the page address of higher page's buddy calculation >> >> Calculate the page address of higher page's buddy should be based >> higher_page with the

Re: Fixup the page of buddy_higher address's calculation

2012/8/23 Michal Hocko : > On Thu 23-08-12 20:30:34, Gavin Shan wrote: >> On Thu, Aug 23, 2012 at 06:21:06PM +0800, Li Haifeng wrote: > [...] >> >>> From d7cd78f9d71a5c9ddeed02724558096f0bb4508a Mon Sep 17 00:00:00 2001 >> >>> From: Haifeng Li &g

Re: Fixup the page of buddy_higher address's calculation

+ (buddy_idx - page_idx)). Maybe, a diagram is easier to understand. |-|-| page combined buddy buddy's page address= page‘s page address + (buddy - page)*sizeof(struct page) Clear? 2012/8/23 Michal Hocko : > On Thu 23-08-12 16:40:13, Li

Re: ARM: why smp_mb() is not needed in the "__mutex_fastpath_lock" and "__mutex_fastpath_unlock" functions

Hi Shan, 2012/7/12 shan kang : > Hello, >I wonder why smp_mb() is not needed in the "__mutex_fastpath_lock" > and "__mutex_fastpath_unlock" functions which are located in the > "arch/arm/include/asm/mutex.h"? >I think "dmb" instruction is necessary there. Why necessary? Could you explain