| lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
|
Open Source and information security mailing list archives
| ||
|
Date: Thu, 22 Dec 2011 14:44:00 +0400
From: Glauber Costa <glommer@...allels.com>
To: Michal Hocko <mhocko@...e.cz>
CC: <davem@...emloft.net>, <linux-kernel@...r.kernel.org>,
<kamezawa.hiroyu@...fujitsu.com>, <netdev@...r.kernel.org>,
<eric.dumazet@...il.com>, <cgroups@...r.kernel.org>,
"Kirill A. Shutemov" <kirill@...temov.name>,
Paul Menage <paul@...lmenage.org>,
Greg Thelen <gthelen@...gle.com>,
Johannes Weiner <jweiner@...hat.com>
Subject: Re: [PATCH] Partial revert "Basic kernel memory functionality for
the Memory Controller"
On 12/22/2011 02:43 PM, Michal Hocko wrote:
> On Thu 22-12-11 12:53:10, Glauber Costa wrote:
>> This reverts commit e5671dfae59b165e2adfd4dfbdeab11ac8db5bda.
>>
>> After a follow up discussion with Michal, it was agreed it would
>> be better to leave the kmem controller with just the tcp files,
>> deferring the behavior of the other general memory.kmem.* files
>> for a later time, when more caches are controlled.
>
> "Because generic kmem files are not used by tcp accounting and it is
> not clear how other slab caches would fit into the scheme."
Should I respin?
>>
>> We are reverting the original commit so we can track the reference.
>> Part of the patch is kept, because it was used by the later tcp
>> code. Conflicts are shown in the bottom. init/Kconfig is removed from
>> the revert entirely.
>>
>> Signed-off-by: Glauber Costa<glommer@...allels.com>
>> CC: Kirill A. Shutemov<kirill@...temov.name>
>> CC: Paul Menage<paul@...lmenage.org>
>> CC: Greg Thelen<gthelen@...gle.com>
>> CC: Johannes Weiner<jweiner@...hat.com>
>> CC: Michal Hocko<mhocko@...e.cz>
>> CC: David S. Miller<davem@...emloft.net>
>
> Acked-by: Michal Hocko<mhocko@...e.cz>
>
>>
>>
>> Conflicts:
>>
>> Documentation/cgroups/memory.txt
>> mm/memcontrol.c
>> ---
>> Documentation/cgroups/memory.txt | 22 +--------
>> mm/memcontrol.c | 93 +++-----------------------------------
>> 2 files changed, 8 insertions(+), 107 deletions(-)
>>
>> diff --git a/Documentation/cgroups/memory.txt b/Documentation/cgroups/memory.txt
>> index 6922b6c..4d8774f 100644
>> --- a/Documentation/cgroups/memory.txt
>> +++ b/Documentation/cgroups/memory.txt
>> @@ -44,9 +44,8 @@ Features:
>> - oom-killer disable knob and oom-notifier
>> - Root cgroup has no limit controls.
>>
>> - Hugepages is not under control yet. We just manage pages on LRU. To add more
>> - controls, we have to take care of performance. Kernel memory support is work
>> - in progress, and the current version provides basically functionality.
>> + Kernel memory support is work in progress, and the current version provides
>> + basically functionality. (See Section 2.7)
>>
>> Brief summary of control files.
>>
>> @@ -57,11 +56,8 @@ Brief summary of control files.
>> (See 5.5 for details)
>> memory.memsw.usage_in_bytes # show current res_counter usage for memory+Swap
>> (See 5.5 for details)
>> - memory.kmem.usage_in_bytes # show current res_counter usage for kmem only.
>> - (See 2.7 for details)
>> memory.limit_in_bytes # set/show limit of memory usage
>> memory.memsw.limit_in_bytes # set/show limit of memory+Swap usage
>> - memory.kmem.limit_in_bytes # if allowed, set/show limit of kernel memory
>> memory.failcnt # show the number of memory usage hits limits
>> memory.memsw.failcnt # show the number of memory+Swap hits limits
>> memory.max_usage_in_bytes # show max memory usage recorded
>> @@ -76,8 +72,6 @@ Brief summary of control files.
>> memory.oom_control # set/show oom controls.
>> memory.numa_stat # show the number of memory usage per numa node
>>
>> - memory.independent_kmem_limit # select whether or not kernel memory limits are
>> - independent of user limits
>> memory.kmem.tcp.limit_in_bytes # set/show hard limit for tcp buf memory
>> memory.kmem.tcp.usage_in_bytes # show current tcp buf memory allocation
>>
>> @@ -271,21 +265,9 @@ the amount of kernel memory used by the system. Kernel memory is fundamentally
>> different than user memory, since it can't be swapped out, which makes it
>> possible to DoS the system by consuming too much of this precious resource.
>>
>> -Some kernel memory resources may be accounted and limited separately from the
>> -main "kmem" resource. For instance, a slab cache that is considered important
>> -enough to be limited separately may have its own knobs.
>> -
>> Kernel memory limits are not imposed for the root cgroup. Usage for the root
>> cgroup may or may not be accounted.
>>
>> -Memory limits as specified by the standard Memory Controller may or may not
>> -take kernel memory into consideration. This is achieved through the file
>> -memory.independent_kmem_limit. A Value different than 0 will allow for kernel
>> -memory to be controlled separately.
>> -
>> -When kernel memory limits are not independent, the limit values set in
>> -memory.kmem files are ignored.
>> -
>> Currently no soft limit is implemented for kernel memory. It is future work
>> to trigger slab reclaim when those limits are reached.
>>
>> diff --git a/mm/memcontrol.c b/mm/memcontrol.c
>> index 7266202..8cdc915 100644
>> --- a/mm/memcontrol.c
>> +++ b/mm/memcontrol.c
>> @@ -229,10 +229,6 @@ struct mem_cgroup {
>> */
>> struct res_counter memsw;
>> /*
>> - * the counter to account for kmem usage.
>> - */
>> - struct res_counter kmem;
>> - /*
>> * Per cgroup active and inactive list, similar to the
>> * per zone LRU lists.
>> */
>> @@ -283,11 +279,6 @@ struct mem_cgroup {
>> */
>> unsigned long move_charge_at_immigrate;
>> /*
>> - * Should kernel memory limits be stabilished independently
>> - * from user memory ?
>> - */
>> - int kmem_independent_accounting;
>> - /*
>> * percpu counter.
>> */
>> struct mem_cgroup_stat_cpu *stat;
>> @@ -359,14 +350,9 @@ enum charge_type {
>> };
>>
>> /* for encoding cft->private value on file */
>> -
>> -enum mem_type {
>> - _MEM = 0,
>> - _MEMSWAP,
>> - _OOM_TYPE,
>> - _KMEM,
>> -};
>> -
>> +#define _MEM (0)
>> +#define _MEMSWAP (1)
>> +#define _OOM_TYPE (2)
>> #define MEMFILE_PRIVATE(x, val) (((x)<< 16) | (val))
>> #define MEMFILE_TYPE(val) (((val)>> 16)& 0xffff)
>> #define MEMFILE_ATTR(val) ((val)& 0xffff)
>> @@ -3919,17 +3905,10 @@ static inline u64 mem_cgroup_usage(struct mem_cgroup *memcg, bool swap)
>> u64 val;
>>
>> if (!mem_cgroup_is_root(memcg)) {
>> - val = 0;
>> -#ifdef CONFIG_CGROUP_MEM_RES_CTLR_KMEM
>> - if (!memcg->kmem_independent_accounting)
>> - val = res_counter_read_u64(&memcg->kmem, RES_USAGE);
>> -#endif
>> if (!swap)
>> - val += res_counter_read_u64(&memcg->res, RES_USAGE);
>> + return res_counter_read_u64(&memcg->res, RES_USAGE);
>> else
>> - val += res_counter_read_u64(&memcg->memsw, RES_USAGE);
>> -
>> - return val;
>> + return res_counter_read_u64(&memcg->memsw, RES_USAGE);
>> }
>>
>> val = mem_cgroup_recursive_stat(memcg, MEM_CGROUP_STAT_CACHE);
>> @@ -3962,11 +3941,6 @@ static u64 mem_cgroup_read(struct cgroup *cont, struct cftype *cft)
>> else
>> val = res_counter_read_u64(&memcg->memsw, name);
>> break;
>> -#ifdef CONFIG_CGROUP_MEM_RES_CTLR_KMEM
>> - case _KMEM:
>> - val = res_counter_read_u64(&memcg->kmem, name);
>> - break;
>> -#endif
>> default:
>> BUG();
>> break;
>> @@ -4696,59 +4670,8 @@ static int mem_control_numa_stat_open(struct inode *unused, struct file *file)
>> #endif /* CONFIG_NUMA */
>>
>> #ifdef CONFIG_CGROUP_MEM_RES_CTLR_KMEM
>> -static u64 kmem_limit_independent_read(struct cgroup *cgroup, struct cftype *cft)
>> -{
>> - return mem_cgroup_from_cont(cgroup)->kmem_independent_accounting;
>> -}
>> -
>> -static int kmem_limit_independent_write(struct cgroup *cgroup, struct cftype *cft,
>> - u64 val)
>> -{
>> - struct mem_cgroup *memcg = mem_cgroup_from_cont(cgroup);
>> - struct mem_cgroup *parent = parent_mem_cgroup(memcg);
>> -
>> - val = !!val;
>> -
>> - /*
>> - * This follows the same hierarchy restrictions than
>> - * mem_cgroup_hierarchy_write()
>> - */
>> - if (!parent || !parent->use_hierarchy) {
>> - if (list_empty(&cgroup->children))
>> - memcg->kmem_independent_accounting = val;
>> - else
>> - return -EBUSY;
>> - }
>> - else
>> - return -EINVAL;
>> -
>> - return 0;
>> -}
>> -static struct cftype kmem_cgroup_files[] = {
>> - {
>> - .name = "independent_kmem_limit",
>> - .read_u64 = kmem_limit_independent_read,
>> - .write_u64 = kmem_limit_independent_write,
>> - },
>> - {
>> - .name = "kmem.usage_in_bytes",
>> - .private = MEMFILE_PRIVATE(_KMEM, RES_USAGE),
>> - .read_u64 = mem_cgroup_read,
>> - },
>> - {
>> - .name = "kmem.limit_in_bytes",
>> - .private = MEMFILE_PRIVATE(_KMEM, RES_LIMIT),
>> - .read_u64 = mem_cgroup_read,
>> - },
>> -};
>> -
>> static int register_kmem_files(struct cgroup *cont, struct cgroup_subsys *ss)
>> {
>> - int ret = 0;
>> -
>> - ret = cgroup_add_files(cont, ss, kmem_cgroup_files,
>> - ARRAY_SIZE(kmem_cgroup_files));
>> -
>> /*
>> * Part of this would be better living in a separate allocation
>> * function, leaving us with just the cgroup tree population work.
>> @@ -4756,9 +4679,7 @@ static int register_kmem_files(struct cgroup *cont, struct cgroup_subsys *ss)
>> * is only initialized after cgroup creation. I found the less
>> * cumbersome way to deal with it to defer it all to populate time
>> */
>> - if (!ret)
>> - ret = mem_cgroup_sockets_init(cont, ss);
>> - return ret;
>> + return mem_cgroup_sockets_init(cont, ss);
>> };
>>
>> static void kmem_cgroup_destroy(struct cgroup_subsys *ss,
>> @@ -5092,7 +5013,6 @@ mem_cgroup_create(struct cgroup_subsys *ss, struct cgroup *cont)
>> if (parent&& parent->use_hierarchy) {
>> res_counter_init(&memcg->res,&parent->res);
>> res_counter_init(&memcg->memsw,&parent->memsw);
>> - res_counter_init(&memcg->kmem,&parent->kmem);
>> /*
>> * We increment refcnt of the parent to ensure that we can
>> * safely access it on res_counter_charge/uncharge.
>> @@ -5103,7 +5023,6 @@ mem_cgroup_create(struct cgroup_subsys *ss, struct cgroup *cont)
>> } else {
>> res_counter_init(&memcg->res, NULL);
>> res_counter_init(&memcg->memsw, NULL);
>> - res_counter_init(&memcg->kmem, NULL);
>> }
>> memcg->last_scanned_child = 0;
>> memcg->last_scanned_node = MAX_NUMNODES;
>> --
>> 1.7.6.4
>>
>> --
>> To unsubscribe from this list: send the line "unsubscribe cgroups" in
>> the body of a message to majordomo@...r.kernel.org
>> More majordomo info at http://vger.kernel.org/majordomo-info.html
>
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
Powered by blists - more mailing lists