From mboxrd@z Thu Jan 1 00:00:00 1970 From: akpm@linux-foundation.org Subject: + cgroups-make-swap-accounting-default-behavior-configurable.patch added to -mm tree Date: Tue, 16 Nov 2010 12:47:49 -0800 Message-ID: <201011162047.oAGKlnce006741@imap1.linux-foundation.org> Reply-To: linux-kernel@vger.kernel.org Return-path: Received: from smtp1.linux-foundation.org ([140.211.169.13]:44561 "EHLO smtp1.linux-foundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755319Ab0KPUs2 (ORCPT ); Tue, 16 Nov 2010 15:48:28 -0500 Sender: mm-commits-owner@vger.kernel.org List-Id: mm-commits@vger.kernel.org To: mm-commits@vger.kernel.org Cc: mhocko@suse.cz, balbir@linux.vnet.ibm.com, kamezawa.hiroyu@jp.fujitsu.com, nishimura@mxp.nes.nec.co.jp The patch titled cgroups: make swap accounting default behavior configurable has been added to the -mm tree. Its filename is cgroups-make-swap-accounting-default-behavior-configurable.patch Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/SubmitChecklist when testing your code *** See http://userweb.kernel.org/~akpm/stuff/added-to-mm.txt to find out what to do about this The current -mm tree may be found at http://userweb.kernel.org/~akpm/mmotm/ ------------------------------------------------------ Subject: cgroups: make swap accounting default behavior configurable From: Michal Hocko Swap accounting can be configured by CONFIG_CGROUP_MEM_RES_CTLR_SWAP configuration option and then it is turned on by default. There is a boot option (noswapaccount) which can disable this feature. This makes it hard for distributors to enable the configuration option as this feature leads to a bigger memory consumption and this is a no-go for general purpose distribution kernel. On the other hand swap accounting may be very useful for some workloads. This patch adds a new Kconfig option which controls the default behavior (CGROUP_MEM_RES_CTLR_SWAP_ENABLED). If the option is selected then the feature is turned on by default. It also adds a new boot parameter swapaccount which (contrary to noswapaccount) enables the feature. (I would consider swapaccount=yes|no semantic with removed noswapaccount parameter much better but this parameter is kind of API which might be in use and unexpected breakage is no-go.) The default behavior is unchanged (if CONFIG_CGROUP_MEM_RES_CTLR_SWAP is enabled then CONFIG_CGROUP_MEM_RES_CTLR_SWAP_ENABLED is enabled as well) Signed-off-by: Michal Hocko Acked-by: Daisuke Nishimura Cc: Balbir Singh Cc: KAMEZAWA Hiroyuki Signed-off-by: Andrew Morton --- Documentation/kernel-parameters.txt | 3 +++ init/Kconfig | 13 +++++++++++++ mm/memcontrol.c | 15 ++++++++++++++- 3 files changed, 30 insertions(+), 1 deletion(-) diff -puN Documentation/kernel-parameters.txt~cgroups-make-swap-accounting-default-behavior-configurable Documentation/kernel-parameters.txt --- a/Documentation/kernel-parameters.txt~cgroups-make-swap-accounting-default-behavior-configurable +++ a/Documentation/kernel-parameters.txt @@ -2385,6 +2385,9 @@ and is between 256 and 4096 characters. improve throughput, but will also increase the amount of memory reserved for use by the client. + swapaccount [KNL] Enable accounting of swap in memory resource + controller. (See Documentation/cgroups/memory.txt) + swiotlb= [IA-64] Number of I/O TLB slabs switches= [HW,M68k] diff -puN init/Kconfig~cgroups-make-swap-accounting-default-behavior-configurable init/Kconfig --- a/init/Kconfig~cgroups-make-swap-accounting-default-behavior-configurable +++ a/init/Kconfig @@ -651,6 +651,19 @@ config CGROUP_MEM_RES_CTLR_SWAP if boot option "noswapaccount" is set, swap will not be accounted. Now, memory usage of swap_cgroup is 2 bytes per entry. If swap page size is 4096bytes, 512k per 1Gbytes of swap. +config CGROUP_MEM_RES_CTLR_SWAP_ENABLED + bool "Memory Resource Controller Swap Extension enabled by default" + depends on CGROUP_MEM_RES_CTLR_SWAP + default y + help + Memory Resource Controller Swap Extension comes with its price in + a bigger memory consumption. General purpose distribution kernels + which want to enable the feautre but keep it disabled by default + and let the user enable it by swapaccount boot command line + parameter should have this option unselected. + For those who want to have the feature enabled by default should + select this option (if, for some reason, they need to disable it + then noswapaccount does the trick). menuconfig CGROUP_SCHED bool "Group CPU scheduler" diff -puN mm/memcontrol.c~cgroups-make-swap-accounting-default-behavior-configurable mm/memcontrol.c --- a/mm/memcontrol.c~cgroups-make-swap-accounting-default-behavior-configurable +++ a/mm/memcontrol.c @@ -61,7 +61,14 @@ struct mem_cgroup *root_mem_cgroup __rea #ifdef CONFIG_CGROUP_MEM_RES_CTLR_SWAP /* Turned on only when memory cgroup is enabled && really_do_swap_account = 1 */ int do_swap_account __read_mostly; -static int really_do_swap_account __initdata = 1; /* for remember boot option*/ + +/* for remember boot option*/ +#ifdef CONFIG_CGROUP_MEM_RES_CTLR_SWAP_ENABLED +static int really_do_swap_account __initdata = 1; +#else +static int really_do_swap_account __initdata = 0; +#endif + #else #define do_swap_account (0) #endif @@ -4920,6 +4927,12 @@ struct cgroup_subsys mem_cgroup_subsys = }; #ifdef CONFIG_CGROUP_MEM_RES_CTLR_SWAP +static int __init enable_swap_account(char *s) +{ + really_do_swap_account = 1; + return 1; +} +__setup("swapaccount", enable_swap_account); static int __init disable_swap_account(char *s) { _ Patches currently in -mm which might be from mhocko@suse.cz are cgroups-make-swap-accounting-default-behavior-configurable.patch