* [PATCH] memcg: enable accounting for pids in nested pid namespaces @ 2021-04-22 5:44 Vasily Averin 2021-04-24 11:54 ` Vasily Averin ` (2 more replies) 0 siblings, 3 replies; 16+ messages in thread From: Vasily Averin @ 2021-04-22 5:44 UTC (permalink / raw) To: cgroups-u79uwXL29TY76Z2rM5mHXA, Michal Hocko Cc: Christian Brauner, Serge Hallyn, Roman Gushchin init_pid_ns.pid_cachep have enabled memcg accounting, though this setting was disabled for nested pid namespaces. Signed-off-by: Vasily Averin <vvs-5HdwGun5lf+gSpxsJD1C4w@public.gmane.org> --- kernel/pid_namespace.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/kernel/pid_namespace.c b/kernel/pid_namespace.c index 6cd6715..a46a372 100644 --- a/kernel/pid_namespace.c +++ b/kernel/pid_namespace.c @@ -51,7 +51,8 @@ static struct kmem_cache *create_pid_cachep(unsigned int level) mutex_lock(&pid_caches_mutex); /* Name collision forces to do allocation under mutex. */ if (!*pkc) - *pkc = kmem_cache_create(name, len, 0, SLAB_HWCACHE_ALIGN, 0); + *pkc = kmem_cache_create(name, len, 0, + SLAB_HWCACHE_ALIGN | SLAB_ACCOUNT, 0); mutex_unlock(&pid_caches_mutex); /* current can fail, but someone else can succeed. */ return READ_ONCE(*pkc); -- 1.8.3.1 ^ permalink raw reply related [flat|nested] 16+ messages in thread
* [PATCH v2 0/1] memcg: enable accounting for pids in nested pid namespaces [not found] ` <7b777e22-5b0d-7444-343d-92cbfae5f8b4-5HdwGun5lf+gSpxsJD1C4w@public.gmane.org> @ 2021-04-24 11:54 ` Vasily Averin 2021-04-23 16:54 ` Michal Koutný 2021-07-14 7:43 ` Christian Brauner 2 siblings, 0 replies; 16+ messages in thread From: Vasily Averin @ 2021-04-24 11:54 UTC (permalink / raw) To: Michal Hocko, cgroups Cc: linux-kernel, Roman Gushchin, Christian Brauner, Michal Koutný, Serge Hallyn Pid was one the first kernel objects enabled for memcg accounting, see 5d097056c9a0 ("kmemcg: account certain kmem allocations to memcg") init_pid_ns.pid_cachep marked by SLAB_ACCOUNT and we can expect that any new pids in the system are memcg-accounted. Though recently I've noticed that it is wrong. nested pid namespaces creates own slab caches for pid objects, nested pids have increased size because contain id both for all parent and for own pid namespaces. The problem is that these slab caches are _NOT_ marked by SLAB_ACCOUNT,as a result any pids allocated in nested pid namespaces are not memcg-accounted. Pid struct in nested pid namespace consumes up to 500 bytes memory, 100000 such objects gives us up to ~50Mb unaccounted memory. This allow container to exceed assigned memcg limits. For me this issue lookslike bug and I would like to ask to push this fix both to upstream and to stable Vasily Averin (1): memcg: enable accounting for pids in nested pid namespaces kernel/pid_namespace.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) -- 1.8.3.1 ^ permalink raw reply [flat|nested] 16+ messages in thread
* [PATCH v2 0/1] memcg: enable accounting for pids in nested pid namespaces @ 2021-04-24 11:54 ` Vasily Averin 0 siblings, 0 replies; 16+ messages in thread From: Vasily Averin @ 2021-04-24 11:54 UTC (permalink / raw) To: Michal Hocko, cgroups-u79uwXL29TY76Z2rM5mHXA Cc: linux-kernel-u79uwXL29TY76Z2rM5mHXA, Roman Gushchin, Christian Brauner, Michal Koutný, Serge Hallyn Pid was one the first kernel objects enabled for memcg accounting, see 5d097056c9a0 ("kmemcg: account certain kmem allocations to memcg") init_pid_ns.pid_cachep marked by SLAB_ACCOUNT and we can expect that any new pids in the system are memcg-accounted. Though recently I've noticed that it is wrong. nested pid namespaces creates own slab caches for pid objects, nested pids have increased size because contain id both for all parent and for own pid namespaces. The problem is that these slab caches are _NOT_ marked by SLAB_ACCOUNT,as a result any pids allocated in nested pid namespaces are not memcg-accounted. Pid struct in nested pid namespace consumes up to 500 bytes memory, 100000 such objects gives us up to ~50Mb unaccounted memory. This allow container to exceed assigned memcg limits. For me this issue lookslike bug and I would like to ask to push this fix both to upstream and to stable Vasily Averin (1): memcg: enable accounting for pids in nested pid namespaces kernel/pid_namespace.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) -- 1.8.3.1 ^ permalink raw reply [flat|nested] 16+ messages in thread
* [PATCH v2 1/1] memcg: enable accounting for pids in nested pid namespaces [not found] ` <7b777e22-5b0d-7444-343d-92cbfae5f8b4-5HdwGun5lf+gSpxsJD1C4w@public.gmane.org> @ 2021-04-24 11:54 ` Vasily Averin 2021-04-23 16:54 ` Michal Koutný 2021-07-14 7:43 ` Christian Brauner 2 siblings, 0 replies; 16+ messages in thread From: Vasily Averin @ 2021-04-24 11:54 UTC (permalink / raw) To: Michal Hocko, cgroups Cc: linux-kernel, Roman Gushchin, Christian Brauner, Michal Koutný, Serge Hallyn Commit 5d097056c9a0 ("kmemcg: account certain kmem allocations to memcg") enabled memcg accounting for pids allocated from init_pid_ns.pid_cachep, but forgot to adjust the setting for nested pid namespaces. As a result, pid memory is not accounted exactly where it is really needed, inside memcg-limited containers with their own pid namespaces. Pid was one the first kernel objects enabled for memcg accounting. init_pid_ns.pid_cachep marked by SLAB_ACCOUNT and we can expect that any new pids in the system are memcg-accounted. Though recently I've noticed that it is wrong. nested pid namespaces creates own slab caches for pid objects, nested pids have increased size because contain id both for all parent and for own pid namespaces. The problem is that these slab caches are _NOT_ marked by SLAB_ACCOUNT, as a result any pids allocated in nested pid namespaces are not memcg-accounted. Pid struct in nested pid namespace consumes up to 500 bytes memory, 100000 such objects gives us up to ~50Mb unaccounted memory, this allow container to exceed assigned memcg limits. Fixes: 5d097056c9a0 ("kmemcg: account certain kmem allocations to memcg") Cc: stable@vger.kernel.org Signed-off-by: Vasily Averin <vvs@virtuozzo.com> Reviewed-by: Michal Koutný <mkoutny@suse.com> Acked-by: Christian Brauner <christian.brauner@ubuntu.com> Acked-by: Roman Gushchin <guro@fb.com> --- kernel/pid_namespace.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/kernel/pid_namespace.c b/kernel/pid_namespace.c index 6cd6715..a46a372 100644 --- a/kernel/pid_namespace.c +++ b/kernel/pid_namespace.c @@ -51,7 +51,8 @@ static struct kmem_cache *create_pid_cachep(unsigned int level) mutex_lock(&pid_caches_mutex); /* Name collision forces to do allocation under mutex. */ if (!*pkc) - *pkc = kmem_cache_create(name, len, 0, SLAB_HWCACHE_ALIGN, 0); + *pkc = kmem_cache_create(name, len, 0, + SLAB_HWCACHE_ALIGN | SLAB_ACCOUNT, 0); mutex_unlock(&pid_caches_mutex); /* current can fail, but someone else can succeed. */ return READ_ONCE(*pkc); -- 1.8.3.1 ^ permalink raw reply related [flat|nested] 16+ messages in thread
* [PATCH v2 1/1] memcg: enable accounting for pids in nested pid namespaces @ 2021-04-24 11:54 ` Vasily Averin 0 siblings, 0 replies; 16+ messages in thread From: Vasily Averin @ 2021-04-24 11:54 UTC (permalink / raw) To: Michal Hocko, cgroups-u79uwXL29TY76Z2rM5mHXA Cc: linux-kernel-u79uwXL29TY76Z2rM5mHXA, Roman Gushchin, Christian Brauner, Michal Koutný, Serge Hallyn Commit 5d097056c9a0 ("kmemcg: account certain kmem allocations to memcg") enabled memcg accounting for pids allocated from init_pid_ns.pid_cachep, but forgot to adjust the setting for nested pid namespaces. As a result, pid memory is not accounted exactly where it is really needed, inside memcg-limited containers with their own pid namespaces. Pid was one the first kernel objects enabled for memcg accounting. init_pid_ns.pid_cachep marked by SLAB_ACCOUNT and we can expect that any new pids in the system are memcg-accounted. Though recently I've noticed that it is wrong. nested pid namespaces creates own slab caches for pid objects, nested pids have increased size because contain id both for all parent and for own pid namespaces. The problem is that these slab caches are _NOT_ marked by SLAB_ACCOUNT, as a result any pids allocated in nested pid namespaces are not memcg-accounted. Pid struct in nested pid namespace consumes up to 500 bytes memory, 100000 such objects gives us up to ~50Mb unaccounted memory, this allow container to exceed assigned memcg limits. Fixes: 5d097056c9a0 ("kmemcg: account certain kmem allocations to memcg") Cc: stable-u79uwXL29TY76Z2rM5mHXA@public.gmane.org Signed-off-by: Vasily Averin <vvs-5HdwGun5lf+gSpxsJD1C4w@public.gmane.org> Reviewed-by: Michal Koutn√Ω <mkoutny-IBi9RG/b67k@public.gmane.org> Acked-by: Christian Brauner <christian.brauner-GeWIH/nMZzLQT0dZR+AlfA@public.gmane.org> Acked-by: Roman Gushchin <guro-b10kYP2dOMg@public.gmane.org> --- kernel/pid_namespace.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/kernel/pid_namespace.c b/kernel/pid_namespace.c index 6cd6715..a46a372 100644 --- a/kernel/pid_namespace.c +++ b/kernel/pid_namespace.c @@ -51,7 +51,8 @@ static struct kmem_cache *create_pid_cachep(unsigned int level) mutex_lock(&pid_caches_mutex); /* Name collision forces to do allocation under mutex. */ if (!*pkc) - *pkc = kmem_cache_create(name, len, 0, SLAB_HWCACHE_ALIGN, 0); + *pkc = kmem_cache_create(name, len, 0, + SLAB_HWCACHE_ALIGN | SLAB_ACCOUNT, 0); mutex_unlock(&pid_caches_mutex); /* current can fail, but someone else can succeed. */ return READ_ONCE(*pkc); -- 1.8.3.1 ^ permalink raw reply related [flat|nested] 16+ messages in thread
* Re: [PATCH v2 1/1] memcg: enable accounting for pids in nested pid namespaces 2021-04-24 11:54 ` Vasily Averin @ 2021-04-26 19:39 ` Shakeel Butt -1 siblings, 0 replies; 16+ messages in thread From: Shakeel Butt @ 2021-04-26 19:39 UTC (permalink / raw) To: Vasily Averin Cc: Michal Hocko, Cgroups, LKML, Roman Gushchin, Christian Brauner, Michal Koutný, Serge Hallyn On Sat, Apr 24, 2021 at 4:54 AM Vasily Averin <vvs@virtuozzo.com> wrote: > > Commit 5d097056c9a0 ("kmemcg: account certain kmem allocations to memcg") > enabled memcg accounting for pids allocated from init_pid_ns.pid_cachep, > but forgot to adjust the setting for nested pid namespaces. > As a result, pid memory is not accounted exactly where it is really needed, > inside memcg-limited containers with their own pid namespaces. > > Pid was one the first kernel objects enabled for memcg accounting. > init_pid_ns.pid_cachep marked by SLAB_ACCOUNT and we can expect that > any new pids in the system are memcg-accounted. > > Though recently I've noticed that it is wrong. nested pid namespaces creates > own slab caches for pid objects, nested pids have increased size because contain > id both for all parent and for own pid namespaces. The problem is that these slab > caches are _NOT_ marked by SLAB_ACCOUNT, as a result any pids allocated in > nested pid namespaces are not memcg-accounted. > > Pid struct in nested pid namespace consumes up to 500 bytes memory, > 100000 such objects gives us up to ~50Mb unaccounted memory, > this allow container to exceed assigned memcg limits. > > Fixes: 5d097056c9a0 ("kmemcg: account certain kmem allocations to memcg") > Cc: stable@vger.kernel.org > Signed-off-by: Vasily Averin <vvs@virtuozzo.com> > Reviewed-by: Michal Koutný <mkoutny@suse.com> > Acked-by: Christian Brauner <christian.brauner@ubuntu.com> > Acked-by: Roman Gushchin <guro@fb.com> Reviewed-by: Shakeel Butt <shakeelb@google.com> ^ permalink raw reply [flat|nested] 16+ messages in thread
* Re: [PATCH v2 1/1] memcg: enable accounting for pids in nested pid namespaces @ 2021-04-26 19:39 ` Shakeel Butt 0 siblings, 0 replies; 16+ messages in thread From: Shakeel Butt @ 2021-04-26 19:39 UTC (permalink / raw) To: Vasily Averin Cc: Michal Hocko, Cgroups, LKML, Roman Gushchin, Christian Brauner, Michal Koutný, Serge Hallyn On Sat, Apr 24, 2021 at 4:54 AM Vasily Averin <vvs@virtuozzo.com> wrote: > > Commit 5d097056c9a0 ("kmemcg: account certain kmem allocations to memcg") > enabled memcg accounting for pids allocated from init_pid_ns.pid_cachep, > but forgot to adjust the setting for nested pid namespaces. > As a result, pid memory is not accounted exactly where it is really needed, > inside memcg-limited containers with their own pid namespaces. > > Pid was one the first kernel objects enabled for memcg accounting. > init_pid_ns.pid_cachep marked by SLAB_ACCOUNT and we can expect that > any new pids in the system are memcg-accounted. > > Though recently I've noticed that it is wrong. nested pid namespaces creates > own slab caches for pid objects, nested pids have increased size because contain > id both for all parent and for own pid namespaces. The problem is that these slab > caches are _NOT_ marked by SLAB_ACCOUNT, as a result any pids allocated in > nested pid namespaces are not memcg-accounted. > > Pid struct in nested pid namespace consumes up to 500 bytes memory, > 100000 such objects gives us up to ~50Mb unaccounted memory, > this allow container to exceed assigned memcg limits. > > Fixes: 5d097056c9a0 ("kmemcg: account certain kmem allocations to memcg") > Cc: stable@vger.kernel.org > Signed-off-by: Vasily Averin <vvs@virtuozzo.com> > Reviewed-by: Michal Koutn√Ω <mkoutny@suse.com> > Acked-by: Christian Brauner <christian.brauner@ubuntu.com> > Acked-by: Roman Gushchin <guro@fb.com> Reviewed-by: Shakeel Butt <shakeelb@google.com> ^ permalink raw reply [flat|nested] 16+ messages in thread
* Re: [PATCH v2 1/1] memcg: enable accounting for pids in nested pid namespaces @ 2021-07-14 6:31 ` Vasily Averin 0 siblings, 0 replies; 16+ messages in thread From: Vasily Averin @ 2021-07-14 6:31 UTC (permalink / raw) To: Andrew Morton Cc: linux-kernel, Roman Gushchin, Christian Brauner, Michal Koutný, Serge Hallyn, cgroups, Michal Hocko Dear Andrew, could you please pick up this patch and add Reviewed-by: Shakeel Butt <shakeelb@google.com> Thank you, Vasily Averin On 4/24/21 2:54 PM, Vasily Averin wrote: > Commit 5d097056c9a0 ("kmemcg: account certain kmem allocations to memcg") > enabled memcg accounting for pids allocated from init_pid_ns.pid_cachep, > but forgot to adjust the setting for nested pid namespaces. > As a result, pid memory is not accounted exactly where it is really needed, > inside memcg-limited containers with their own pid namespaces. > > Pid was one the first kernel objects enabled for memcg accounting. > init_pid_ns.pid_cachep marked by SLAB_ACCOUNT and we can expect that > any new pids in the system are memcg-accounted. > > Though recently I've noticed that it is wrong. nested pid namespaces creates > own slab caches for pid objects, nested pids have increased size because contain > id both for all parent and for own pid namespaces. The problem is that these slab > caches are _NOT_ marked by SLAB_ACCOUNT, as a result any pids allocated in > nested pid namespaces are not memcg-accounted. > > Pid struct in nested pid namespace consumes up to 500 bytes memory, > 100000 such objects gives us up to ~50Mb unaccounted memory, > this allow container to exceed assigned memcg limits. > > Fixes: 5d097056c9a0 ("kmemcg: account certain kmem allocations to memcg") > Cc: stable@vger.kernel.org > Signed-off-by: Vasily Averin <vvs@virtuozzo.com> > Reviewed-by: Michal Koutný <mkoutny@suse.com> > Acked-by: Christian Brauner <christian.brauner@ubuntu.com> > Acked-by: Roman Gushchin <guro@fb.com> > --- > kernel/pid_namespace.c | 3 ++- > 1 file changed, 2 insertions(+), 1 deletion(-) > > diff --git a/kernel/pid_namespace.c b/kernel/pid_namespace.c > index 6cd6715..a46a372 100644 > --- a/kernel/pid_namespace.c > +++ b/kernel/pid_namespace.c > @@ -51,7 +51,8 @@ static struct kmem_cache *create_pid_cachep(unsigned int level) > mutex_lock(&pid_caches_mutex); > /* Name collision forces to do allocation under mutex. */ > if (!*pkc) > - *pkc = kmem_cache_create(name, len, 0, SLAB_HWCACHE_ALIGN, 0); > + *pkc = kmem_cache_create(name, len, 0, > + SLAB_HWCACHE_ALIGN | SLAB_ACCOUNT, 0); > mutex_unlock(&pid_caches_mutex); > /* current can fail, but someone else can succeed. */ > return READ_ONCE(*pkc); > ^ permalink raw reply [flat|nested] 16+ messages in thread
* Re: [PATCH v2 1/1] memcg: enable accounting for pids in nested pid namespaces @ 2021-07-14 6:31 ` Vasily Averin 0 siblings, 0 replies; 16+ messages in thread From: Vasily Averin @ 2021-07-14 6:31 UTC (permalink / raw) To: Andrew Morton Cc: linux-kernel-u79uwXL29TY76Z2rM5mHXA, Roman Gushchin, Christian Brauner, Michal Koutný, Serge Hallyn, cgroups-u79uwXL29TY76Z2rM5mHXA, Michal Hocko Dear Andrew, could you please pick up this patch and add Reviewed-by: Shakeel Butt <shakeelb-hpIqsD4AKlfQT0dZR+AlfA@public.gmane.org> Thank you, Vasily Averin On 4/24/21 2:54 PM, Vasily Averin wrote: > Commit 5d097056c9a0 ("kmemcg: account certain kmem allocations to memcg") > enabled memcg accounting for pids allocated from init_pid_ns.pid_cachep, > but forgot to adjust the setting for nested pid namespaces. > As a result, pid memory is not accounted exactly where it is really needed, > inside memcg-limited containers with their own pid namespaces. > > Pid was one the first kernel objects enabled for memcg accounting. > init_pid_ns.pid_cachep marked by SLAB_ACCOUNT and we can expect that > any new pids in the system are memcg-accounted. > > Though recently I've noticed that it is wrong. nested pid namespaces creates > own slab caches for pid objects, nested pids have increased size because contain > id both for all parent and for own pid namespaces. The problem is that these slab > caches are _NOT_ marked by SLAB_ACCOUNT, as a result any pids allocated in > nested pid namespaces are not memcg-accounted. > > Pid struct in nested pid namespace consumes up to 500 bytes memory, > 100000 such objects gives us up to ~50Mb unaccounted memory, > this allow container to exceed assigned memcg limits. > > Fixes: 5d097056c9a0 ("kmemcg: account certain kmem allocations to memcg") > Cc: stable-u79uwXL29TY76Z2rM5mHXA@public.gmane.org > Signed-off-by: Vasily Averin <vvs-5HdwGun5lf+gSpxsJD1C4w@public.gmane.org> > Reviewed-by: Michal Koutn√Ω <mkoutny-IBi9RG/b67k@public.gmane.org> > Acked-by: Christian Brauner <christian.brauner-GeWIH/nMZzLQT0dZR+AlfA@public.gmane.org> > Acked-by: Roman Gushchin <guro-b10kYP2dOMg@public.gmane.org> > --- > kernel/pid_namespace.c | 3 ++- > 1 file changed, 2 insertions(+), 1 deletion(-) > > diff --git a/kernel/pid_namespace.c b/kernel/pid_namespace.c > index 6cd6715..a46a372 100644 > --- a/kernel/pid_namespace.c > +++ b/kernel/pid_namespace.c > @@ -51,7 +51,8 @@ static struct kmem_cache *create_pid_cachep(unsigned int level) > mutex_lock(&pid_caches_mutex); > /* Name collision forces to do allocation under mutex. */ > if (!*pkc) > - *pkc = kmem_cache_create(name, len, 0, SLAB_HWCACHE_ALIGN, 0); > + *pkc = kmem_cache_create(name, len, 0, > + SLAB_HWCACHE_ALIGN | SLAB_ACCOUNT, 0); > mutex_unlock(&pid_caches_mutex); > /* current can fail, but someone else can succeed. */ > return READ_ONCE(*pkc); > ^ permalink raw reply [flat|nested] 16+ messages in thread
[parent not found: <7b777e22-5b0d-7444-343d-92cbfae5f8b4-5HdwGun5lf+gSpxsJD1C4w@public.gmane.org>]
* Re: [PATCH] memcg: enable accounting for pids in nested pid namespaces [not found] ` <7b777e22-5b0d-7444-343d-92cbfae5f8b4-5HdwGun5lf+gSpxsJD1C4w@public.gmane.org> @ 2021-04-23 1:00 ` Roman Gushchin 2021-04-23 2:09 ` Vasily Averin 2021-04-23 16:54 ` Michal Koutný 2021-07-14 7:43 ` Christian Brauner 2 siblings, 1 reply; 16+ messages in thread From: Roman Gushchin @ 2021-04-23 1:00 UTC (permalink / raw) To: Vasily Averin Cc: cgroups-u79uwXL29TY76Z2rM5mHXA, Michal Hocko, Christian Brauner, Serge Hallyn On Thu, Apr 22, 2021 at 08:44:15AM +0300, Vasily Averin wrote: > init_pid_ns.pid_cachep have enabled memcg accounting, though this > setting was disabled for nested pid namespaces. > > Signed-off-by: Vasily Averin <vvs-5HdwGun5lf+gSpxsJD1C4w@public.gmane.org> > --- > kernel/pid_namespace.c | 3 ++- > 1 file changed, 2 insertions(+), 1 deletion(-) > > diff --git a/kernel/pid_namespace.c b/kernel/pid_namespace.c > index 6cd6715..a46a372 100644 > --- a/kernel/pid_namespace.c > +++ b/kernel/pid_namespace.c > @@ -51,7 +51,8 @@ static struct kmem_cache *create_pid_cachep(unsigned int level) > mutex_lock(&pid_caches_mutex); > /* Name collision forces to do allocation under mutex. */ > if (!*pkc) > - *pkc = kmem_cache_create(name, len, 0, SLAB_HWCACHE_ALIGN, 0); > + *pkc = kmem_cache_create(name, len, 0, > + SLAB_HWCACHE_ALIGN | SLAB_ACCOUNT, 0); > mutex_unlock(&pid_caches_mutex); > /* current can fail, but someone else can succeed. */ > return READ_ONCE(*pkc); > -- > 1.8.3.1 > It looks good to me! It makes total sense to apply the same rules to the root and non-root levels. Acked-by: Roman Gushchin <guro-b10kYP2dOMg@public.gmane.org> Btw, is there any reason why this patch is not included into the series? Thanks! ^ permalink raw reply [flat|nested] 16+ messages in thread
* Re: [PATCH] memcg: enable accounting for pids in nested pid namespaces 2021-04-23 1:00 ` [PATCH] " Roman Gushchin @ 2021-04-23 2:09 ` Vasily Averin [not found] ` <38945563-59ad-fb5e-9f7f-eb65ae4bf55e-5HdwGun5lf+gSpxsJD1C4w@public.gmane.org> 0 siblings, 1 reply; 16+ messages in thread From: Vasily Averin @ 2021-04-23 2:09 UTC (permalink / raw) To: Roman Gushchin Cc: cgroups-u79uwXL29TY76Z2rM5mHXA, Michal Hocko, Christian Brauner, Serge Hallyn On 4/23/21 4:00 AM, Roman Gushchin wrote: > On Thu, Apr 22, 2021 at 08:44:15AM +0300, Vasily Averin wrote: >> init_pid_ns.pid_cachep have enabled memcg accounting, though this >> setting was disabled for nested pid namespaces. >> >> Signed-off-by: Vasily Averin <vvs-5HdwGun5lf+gSpxsJD1C4w@public.gmane.org> >> --- >> kernel/pid_namespace.c | 3 ++- >> 1 file changed, 2 insertions(+), 1 deletion(-) >> >> diff --git a/kernel/pid_namespace.c b/kernel/pid_namespace.c >> index 6cd6715..a46a372 100644 >> --- a/kernel/pid_namespace.c >> +++ b/kernel/pid_namespace.c >> @@ -51,7 +51,8 @@ static struct kmem_cache *create_pid_cachep(unsigned int level) >> mutex_lock(&pid_caches_mutex); >> /* Name collision forces to do allocation under mutex. */ >> if (!*pkc) >> - *pkc = kmem_cache_create(name, len, 0, SLAB_HWCACHE_ALIGN, 0); >> + *pkc = kmem_cache_create(name, len, 0, >> + SLAB_HWCACHE_ALIGN | SLAB_ACCOUNT, 0); >> mutex_unlock(&pid_caches_mutex); >> /* current can fail, but someone else can succeed. */ >> return READ_ONCE(*pkc); >> -- >> 1.8.3.1 >> > > It looks good to me! It makes total sense to apply the same rules to the root > and non-root levels. > > Acked-by: Roman Gushchin <guro-b10kYP2dOMg@public.gmane.org> > > Btw, is there any reason why this patch is not included into the series? It is a bugfix and I think it should be added to upstream ASAP. Another patches adds a new functionality, they can cause questions or objections and anyway can wait. Thank you, Vasily Averin ^ permalink raw reply [flat|nested] 16+ messages in thread
[parent not found: <38945563-59ad-fb5e-9f7f-eb65ae4bf55e-5HdwGun5lf+gSpxsJD1C4w@public.gmane.org>]
* Re: [PATCH] memcg: enable accounting for pids in nested pid namespaces [not found] ` <38945563-59ad-fb5e-9f7f-eb65ae4bf55e-5HdwGun5lf+gSpxsJD1C4w@public.gmane.org> @ 2021-04-23 2:30 ` Roman Gushchin 2021-04-23 2:53 ` Vasily Averin 0 siblings, 1 reply; 16+ messages in thread From: Roman Gushchin @ 2021-04-23 2:30 UTC (permalink / raw) To: Vasily Averin Cc: cgroups-u79uwXL29TY76Z2rM5mHXA, Michal Hocko, Christian Brauner, Serge Hallyn On Fri, Apr 23, 2021 at 05:09:01AM +0300, Vasily Averin wrote: > On 4/23/21 4:00 AM, Roman Gushchin wrote: > > On Thu, Apr 22, 2021 at 08:44:15AM +0300, Vasily Averin wrote: > >> init_pid_ns.pid_cachep have enabled memcg accounting, though this > >> setting was disabled for nested pid namespaces. > >> > >> Signed-off-by: Vasily Averin <vvs-5HdwGun5lf+gSpxsJD1C4w@public.gmane.org> > >> --- > >> kernel/pid_namespace.c | 3 ++- > >> 1 file changed, 2 insertions(+), 1 deletion(-) > >> > >> diff --git a/kernel/pid_namespace.c b/kernel/pid_namespace.c > >> index 6cd6715..a46a372 100644 > >> --- a/kernel/pid_namespace.c > >> +++ b/kernel/pid_namespace.c > >> @@ -51,7 +51,8 @@ static struct kmem_cache *create_pid_cachep(unsigned int level) > >> mutex_lock(&pid_caches_mutex); > >> /* Name collision forces to do allocation under mutex. */ > >> if (!*pkc) > >> - *pkc = kmem_cache_create(name, len, 0, SLAB_HWCACHE_ALIGN, 0); > >> + *pkc = kmem_cache_create(name, len, 0, > >> + SLAB_HWCACHE_ALIGN | SLAB_ACCOUNT, 0); > >> mutex_unlock(&pid_caches_mutex); > >> /* current can fail, but someone else can succeed. */ > >> return READ_ONCE(*pkc); > >> -- > >> 1.8.3.1 > >> > > > > It looks good to me! It makes total sense to apply the same rules to the root > > and non-root levels. > > > > Acked-by: Roman Gushchin <guro-b10kYP2dOMg@public.gmane.org> > > > > Btw, is there any reason why this patch is not included into the series? > > It is a bugfix and I think it should be added to upstream ASAP. Then it would be really useful to add some details on why it's a bug, what kind of problems it causes, etc. If it has to be backported to stable, please, add cc stable/fixes tag. Thanks! ^ permalink raw reply [flat|nested] 16+ messages in thread
* Re: [PATCH] memcg: enable accounting for pids in nested pid namespaces 2021-04-23 2:30 ` Roman Gushchin @ 2021-04-23 2:53 ` Vasily Averin [not found] ` <cd6680e3-edd0-88fa-bb83-b9f2d5a65d5b-5HdwGun5lf+gSpxsJD1C4w@public.gmane.org> 0 siblings, 1 reply; 16+ messages in thread From: Vasily Averin @ 2021-04-23 2:53 UTC (permalink / raw) To: Roman Gushchin Cc: cgroups-u79uwXL29TY76Z2rM5mHXA, Michal Hocko, Christian Brauner, Serge Hallyn On 4/23/21 5:30 AM, Roman Gushchin wrote: > On Fri, Apr 23, 2021 at 05:09:01AM +0300, Vasily Averin wrote: >> On 4/23/21 4:00 AM, Roman Gushchin wrote: >>> On Thu, Apr 22, 2021 at 08:44:15AM +0300, Vasily Averin wrote: >>>> init_pid_ns.pid_cachep have enabled memcg accounting, though this >>>> setting was disabled for nested pid namespaces. >>>> >>>> Signed-off-by: Vasily Averin <vvs-5HdwGun5lf+gSpxsJD1C4w@public.gmane.org> >>>> --- >>>> kernel/pid_namespace.c | 3 ++- >>>> 1 file changed, 2 insertions(+), 1 deletion(-) >>>> >>>> diff --git a/kernel/pid_namespace.c b/kernel/pid_namespace.c >>>> index 6cd6715..a46a372 100644 >>>> --- a/kernel/pid_namespace.c >>>> +++ b/kernel/pid_namespace.c >>>> @@ -51,7 +51,8 @@ static struct kmem_cache *create_pid_cachep(unsigned int level) >>>> mutex_lock(&pid_caches_mutex); >>>> /* Name collision forces to do allocation under mutex. */ >>>> if (!*pkc) >>>> - *pkc = kmem_cache_create(name, len, 0, SLAB_HWCACHE_ALIGN, 0); >>>> + *pkc = kmem_cache_create(name, len, 0, >>>> + SLAB_HWCACHE_ALIGN | SLAB_ACCOUNT, 0); >>>> mutex_unlock(&pid_caches_mutex); >>>> /* current can fail, but someone else can succeed. */ >>>> return READ_ONCE(*pkc); >>>> -- >>>> 1.8.3.1 >>>> >>> >>> It looks good to me! It makes total sense to apply the same rules to the root >>> and non-root levels. >>> >>> Acked-by: Roman Gushchin <guro-b10kYP2dOMg@public.gmane.org> >>> >>> Btw, is there any reason why this patch is not included into the series? >> >> It is a bugfix and I think it should be added to upstream ASAP. > > Then it would be really useful to add some details on why it's a bug, > what kind of problems it causes, etc. If it has to be backported to > stable, please, add cc stable/fixes tag. I mean, in this case we already decided to account pids, but forget to do it. In another cases we did not have final decision about accounting. I doubt we specially denied accounting for pids frem nested pid namespaces, especially because they consumes more memory. We can expect that all pids are accounted -- but it does not happen in fact. ^ permalink raw reply [flat|nested] 16+ messages in thread
[parent not found: <cd6680e3-edd0-88fa-bb83-b9f2d5a65d5b-5HdwGun5lf+gSpxsJD1C4w@public.gmane.org>]
* Re: [PATCH] memcg: enable accounting for pids in nested pid namespaces [not found] ` <cd6680e3-edd0-88fa-bb83-b9f2d5a65d5b-5HdwGun5lf+gSpxsJD1C4w@public.gmane.org> @ 2021-04-23 7:34 ` Christian Brauner 0 siblings, 0 replies; 16+ messages in thread From: Christian Brauner @ 2021-04-23 7:34 UTC (permalink / raw) To: Vasily Averin Cc: Roman Gushchin, cgroups-u79uwXL29TY76Z2rM5mHXA, Michal Hocko, Serge Hallyn On Fri, Apr 23, 2021 at 05:53:43AM +0300, Vasily Averin wrote: > On 4/23/21 5:30 AM, Roman Gushchin wrote: > > On Fri, Apr 23, 2021 at 05:09:01AM +0300, Vasily Averin wrote: > >> On 4/23/21 4:00 AM, Roman Gushchin wrote: > >>> On Thu, Apr 22, 2021 at 08:44:15AM +0300, Vasily Averin wrote: > >>>> init_pid_ns.pid_cachep have enabled memcg accounting, though this > >>>> setting was disabled for nested pid namespaces. > >>>> > >>>> Signed-off-by: Vasily Averin <vvs-5HdwGun5lf+gSpxsJD1C4w@public.gmane.org> > >>>> --- > >>>> kernel/pid_namespace.c | 3 ++- > >>>> 1 file changed, 2 insertions(+), 1 deletion(-) > >>>> > >>>> diff --git a/kernel/pid_namespace.c b/kernel/pid_namespace.c > >>>> index 6cd6715..a46a372 100644 > >>>> --- a/kernel/pid_namespace.c > >>>> +++ b/kernel/pid_namespace.c > >>>> @@ -51,7 +51,8 @@ static struct kmem_cache *create_pid_cachep(unsigned int level) > >>>> mutex_lock(&pid_caches_mutex); > >>>> /* Name collision forces to do allocation under mutex. */ > >>>> if (!*pkc) > >>>> - *pkc = kmem_cache_create(name, len, 0, SLAB_HWCACHE_ALIGN, 0); > >>>> + *pkc = kmem_cache_create(name, len, 0, > >>>> + SLAB_HWCACHE_ALIGN | SLAB_ACCOUNT, 0); > >>>> mutex_unlock(&pid_caches_mutex); > >>>> /* current can fail, but someone else can succeed. */ > >>>> return READ_ONCE(*pkc); > >>>> -- > >>>> 1.8.3.1 > >>>> > >>> > >>> It looks good to me! It makes total sense to apply the same rules to the root > >>> and non-root levels. > >>> > >>> Acked-by: Roman Gushchin <guro-b10kYP2dOMg@public.gmane.org> > >>> > >>> Btw, is there any reason why this patch is not included into the series? > >> > >> It is a bugfix and I think it should be added to upstream ASAP. > > > > Then it would be really useful to add some details on why it's a bug, > > what kind of problems it causes, etc. If it has to be backported to > > stable, please, add cc stable/fixes tag. > > I mean, in this case we already decided to account pids, but forget to do it. > In another cases we did not have final decision about accounting. > > I doubt we specially denied accounting for pids frem nested pid namespaces, > especially because they consumes more memory. > We can expect that all pids are accounted -- but it does not happen in fact. As Roman said you should probably explain this in the cover letter and essentially justify why this should be backported. The thing with changes such as this is that it's easy for someone to reply and go "noone noticed for <n> years so why do we care now?". Otherwise: Acked-by: Christian Brauner <christian.brauner-GeWIH/nMZzLQT0dZR+AlfA@public.gmane.org> Christian ^ permalink raw reply [flat|nested] 16+ messages in thread
* Re: [PATCH] memcg: enable accounting for pids in nested pid namespaces [not found] ` <7b777e22-5b0d-7444-343d-92cbfae5f8b4-5HdwGun5lf+gSpxsJD1C4w@public.gmane.org> 2021-04-23 1:00 ` [PATCH] " Roman Gushchin @ 2021-04-23 16:54 ` Michal Koutný 2021-07-14 7:43 ` Christian Brauner 2 siblings, 0 replies; 16+ messages in thread From: Michal Koutný @ 2021-04-23 16:54 UTC (permalink / raw) To: Vasily Averin Cc: cgroups-u79uwXL29TY76Z2rM5mHXA, Michal Hocko, Christian Brauner, Serge Hallyn, Roman Gushchin [-- Attachment #1: Type: text/plain, Size: 421 bytes --] On Thu, Apr 22, 2021 at 08:44:15AM +0300, Vasily Averin <vvs-5HdwGun5lf+gSpxsJD1C4w@public.gmane.org> wrote: > init_pid_ns.pid_cachep have enabled memcg accounting, though this > setting was disabled for nested pid namespaces. Good catch. Cursory grep of user_namespace.c and nsproxy.c suggests it's the only case of namespace-induced new cache. Reviewed-by: Michal Koutný <mkoutny-IBi9RG/b67k@public.gmane.org> [-- Attachment #2: Digital signature --] [-- Type: application/pgp-signature, Size: 833 bytes --] ^ permalink raw reply [flat|nested] 16+ messages in thread
* Re: [PATCH] memcg: enable accounting for pids in nested pid namespaces [not found] ` <7b777e22-5b0d-7444-343d-92cbfae5f8b4-5HdwGun5lf+gSpxsJD1C4w@public.gmane.org> 2021-04-23 1:00 ` [PATCH] " Roman Gushchin 2021-04-23 16:54 ` Michal Koutný @ 2021-07-14 7:43 ` Christian Brauner 2 siblings, 0 replies; 16+ messages in thread From: Christian Brauner @ 2021-07-14 7:43 UTC (permalink / raw) To: Vasily Averin Cc: cgroups-u79uwXL29TY76Z2rM5mHXA, Michal Hocko, Serge Hallyn, Roman Gushchin On Thu, Apr 22, 2021 at 08:44:15AM +0300, Vasily Averin wrote: > init_pid_ns.pid_cachep have enabled memcg accounting, though this > setting was disabled for nested pid namespaces. > > Signed-off-by: Vasily Averin <vvs-5HdwGun5lf+gSpxsJD1C4w@public.gmane.org> > --- Not sure I already acked this but looks good, Acked-by: Christian Brauner <christian.brauner-GeWIH/nMZzLQT0dZR+AlfA@public.gmane.org> ^ permalink raw reply [flat|nested] 16+ messages in thread
end of thread, other threads:[~2021-07-14 7:43 UTC | newest] Thread overview: 16+ messages (download: mbox.gz / follow: Atom feed) -- links below jump to the message on this page -- 2021-04-22 5:44 [PATCH] memcg: enable accounting for pids in nested pid namespaces Vasily Averin 2021-04-24 11:54 ` [PATCH v2 0/1] " Vasily Averin 2021-04-24 11:54 ` Vasily Averin 2021-04-24 11:54 ` [PATCH v2 1/1] " Vasily Averin 2021-04-24 11:54 ` Vasily Averin 2021-04-26 19:39 ` Shakeel Butt 2021-04-26 19:39 ` Shakeel Butt 2021-07-14 6:31 ` Vasily Averin 2021-07-14 6:31 ` Vasily Averin [not found] ` <7b777e22-5b0d-7444-343d-92cbfae5f8b4-5HdwGun5lf+gSpxsJD1C4w@public.gmane.org> 2021-04-23 1:00 ` [PATCH] " Roman Gushchin 2021-04-23 2:09 ` Vasily Averin [not found] ` <38945563-59ad-fb5e-9f7f-eb65ae4bf55e-5HdwGun5lf+gSpxsJD1C4w@public.gmane.org> 2021-04-23 2:30 ` Roman Gushchin 2021-04-23 2:53 ` Vasily Averin [not found] ` <cd6680e3-edd0-88fa-bb83-b9f2d5a65d5b-5HdwGun5lf+gSpxsJD1C4w@public.gmane.org> 2021-04-23 7:34 ` Christian Brauner 2021-04-23 16:54 ` Michal Koutný 2021-07-14 7:43 ` Christian Brauner
This is an external index of several public inboxes, see mirroring instructions on how to clone and mirror all data and code used by this external index.