A-Team_Digital_Solutions/android_kernel_motorola_sm6375
Watch
2
0
Fork
You've already forked android_kernel_motorola_sm6375
 0
mirror of https://github.com/BobTheBlinker/android_kernel_motorola_sm6375.git synced 2026-10-28 10:41:38 -04:00
Code Issues Projects Releases Packages Wiki Activity

ipc: introduce obtaining a lockless ipc object

Browse source 
Through ipc_lock() and therefore ipc_lock_check() we currently return the
locked ipc object.  This is not necessary for all situations and can,
therefore, cause unnecessary ipc lock contention.

Introduce analogous ipc_obtain_object() and ipc_obtain_object_check()
functions that only lookup and return the ipc object.

Both these functions must be called within the RCU read critical section.

[[email protected]: propagate the ipc_obtain_object() errno from ipc_lock()]
Signed-off-by: Davidlohr Bueso <[email protected]>
Signed-off-by: Rik van Riel <[email protected]>
Reviewed-by: Chegu Vinod <[email protected]>
Acked-by: Michel Lespinasse <[email protected]>
Cc: Emmanuel Benisty <[email protected]>
Cc: Jason Low <[email protected]>
Cc: Peter Hurley <[email protected]>
Cc: Stanislav Kinsbursky <[email protected]>
Tested-by: Sedat Dilek <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
This commit is contained in:
Davidlohr Bueso 2013-04-30 19:15:19 -07:00 • committed by Linus Torvalds
commit 4d2bff5eb8
2 changed files with 59 additions and 14 deletions
Download patch file Download diff file Expand all files Collapse all files

2
ipc/util.h
View file

@ -123,6 +123,7 @@ void ipc_rcu_getref(void *ptr);
void ipc_rcu_putref(void *ptr);
struct kern_ipc_perm *ipc_lock(struct ipc_ids *, int);
struct kern_ipc_perm *ipc_obtain_object(struct ipc_ids *ids, int id);
void kernel_to_ipc64_perm(struct kern_ipc_perm *in, struct ipc64_perm *out);
void ipc64_perm_to_ipc_perm(struct ipc64_perm *in, struct ipc_perm *out);
@ -168,6 +169,7 @@ static inline void ipc_unlock(struct kern_ipc_perm *perm)
}
struct kern_ipc_perm *ipc_lock_check(struct ipc_ids *ids, int id);
struct kern_ipc_perm *ipc_obtain_object_check(struct ipc_ids *ids, int id);
int ipcget(struct ipc_namespace *ns, struct ipc_ids *ids,
struct ipc_ops *ops, struct ipc_params *params);
void free_ipcs(struct ipc_namespace *ns, struct ipc_ids *ids,