[PATCH 1/2] net: fix sleeping while atomic problem in sock mem_cgroup.
From: Glauber Costa <hidden>
Date: 2011-12-16 10:53:25
Also in:
cgroups, lkml
Subsystem:
networking [general], networking [sockets], the rest · Maintainers:
"David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Kuniyuki Iwashima, Willem de Bruijn, Linus Torvalds
We can't scan the proto_list to initialize sock cgroups, as it holds a rwlock, and we also want to keep the code generic enough to avoid calling the initialization functions of protocols directly, Convert proto_list_lock into a mutex, so we can sleep and do the necessary allocations. This lock is seldom taken, so there shouldn't be any performance penalties associated with that Signed-off-by: Glauber Costa <redacted> CC: Hiroyouki Kamezawa <redacted> CC: David S. Miller <davem-fT/PcQaiUtIeIZ0/mPfg9Q@public.gmane.org> CC: Eric Dumazet <redacted> CC: Stephen Rothwell <redacted> CC: Randy Dunlap <rdunlap-/UHa2rfvQTnk1uMJSBkQmQ@public.gmane.org> --- net/core/sock.c | 28 ++++++++++++++-------------- 1 files changed, 14 insertions(+), 14 deletions(-)
diff --git a/net/core/sock.c b/net/core/sock.c
index 5a6a906..0c67fac 100644
--- a/net/core/sock.c
+++ b/net/core/sock.c@@ -136,7 +136,7 @@ #include <net/tcp.h> #endif -static DEFINE_RWLOCK(proto_list_lock); +static DEFINE_MUTEX(proto_list_mutex); static LIST_HEAD(proto_list); #ifdef CONFIG_CGROUP_MEM_RES_CTLR_KMEM
@@ -145,7 +145,7 @@ int mem_cgroup_sockets_init(struct cgroup *cgrp, struct cgroup_subsys *ss) struct proto *proto; int ret = 0; - read_lock(&proto_list_lock); + mutex_lock(&proto_list_mutex); list_for_each_entry(proto, &proto_list, node) { if (proto->init_cgroup) { ret = proto->init_cgroup(cgrp, ss);
@@ -154,13 +154,13 @@ int mem_cgroup_sockets_init(struct cgroup *cgrp, struct cgroup_subsys *ss) } } - read_unlock(&proto_list_lock); + mutex_unlock(&proto_list_mutex); return ret; out: list_for_each_entry_continue_reverse(proto, &proto_list, node) if (proto->destroy_cgroup) proto->destroy_cgroup(cgrp, ss); - read_unlock(&proto_list_lock); + mutex_unlock(&proto_list_mutex); return ret; }
@@ -168,11 +168,11 @@ void mem_cgroup_sockets_destroy(struct cgroup *cgrp, struct cgroup_subsys *ss) { struct proto *proto; - read_lock(&proto_list_lock); + mutex_lock(&proto_list_mutex); list_for_each_entry_reverse(proto, &proto_list, node) if (proto->destroy_cgroup) proto->destroy_cgroup(cgrp, ss); - read_unlock(&proto_list_lock); + mutex_unlock(&proto_list_mutex); } #endif
@@ -2479,10 +2479,10 @@ int proto_register(struct proto *prot, int alloc_slab) } } - write_lock(&proto_list_lock); + mutex_lock(&proto_list_mutex); list_add(&prot->node, &proto_list); assign_proto_idx(prot); - write_unlock(&proto_list_lock); + mutex_unlock(&proto_list_mutex); return 0; out_free_timewait_sock_slab_name:
@@ -2505,10 +2505,10 @@ EXPORT_SYMBOL(proto_register); void proto_unregister(struct proto *prot) { - write_lock(&proto_list_lock); + mutex_lock(&proto_list_mutex); release_proto_idx(prot); list_del(&prot->node); - write_unlock(&proto_list_lock); + mutex_unlock(&proto_list_mutex); if (prot->slab != NULL) { kmem_cache_destroy(prot->slab);
@@ -2531,9 +2531,9 @@ EXPORT_SYMBOL(proto_unregister); #ifdef CONFIG_PROC_FS static void *proto_seq_start(struct seq_file *seq, loff_t *pos) - __acquires(proto_list_lock) + __acquires(proto_list_mutex) { - read_lock(&proto_list_lock); + mutex_lock(&proto_list_mutex); return seq_list_start_head(&proto_list, *pos); }
@@ -2543,9 +2543,9 @@ static void *proto_seq_next(struct seq_file *seq, void *v, loff_t *pos) } static void proto_seq_stop(struct seq_file *seq, void *v) - __releases(proto_list_lock) + __releases(proto_list_mutex) { - read_unlock(&proto_list_lock); + mutex_unlock(&proto_list_mutex); } static char proto_method_implemented(const void *method)
--
1.7.6.4
--
To unsubscribe from this list: send the line "unsubscribe cgroups" in
the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org
More majordomo info at http://vger.kernel.org/majordomo-info.html