user/sven/linux.git/include/linux/sem.h, branch v3.2.78

include/linux/sem.h: make sysv_sem empty if SYSVIPC is disabled

2011-11-02T23:07:01Z

For the sysvsem undo, each task struct contains a sysv_sem structure with a pointer to the undo information. This pointer is only necessary if sysvipc is enabled - thus the pointer can be made conditional on CONFIG_SYSVIPC. Signed-off-by: Manfred Spraul Acked-by: Peter Zijlstra Cc: Thomas Gleixner Cc: Mike Galbraith Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

ipc/sem.c: remove private structures from public header file

2011-11-02T23:07:01Z

include/linux/sem.h contains several structures that are only used within ipc/sem.c. The patch moves them into ipc/sem.c - there is no need to expose the structures to the whole kernel. No functional changes, only whitespace cleanups and 80-char per line fixes. Signed-off-by: Manfred Spraul Acked-by: Peter Zijlstra Cc: Thomas Gleixner Cc: Mike Galbraith Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

atomic: use

2011-07-26T23:49:47Z

This allows us to move duplicated code in (atomic_inc_not_zero() for now) to Signed-off-by: Arun Sharma Reviewed-by: Eric Dumazet Cc: Ingo Molnar Cc: David Miller Cc: Eric Dumazet Acked-by: Mike Frysinger Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

ipc/sem.c: cacheline align the ipc spinlock for semaphores

2010-05-27T16:12:49Z

Cacheline align the spinlock for sysv semaphores. Without the patch, the spinlock and sem_otime [written by every semop that modified the array] and sem_base [read in the hot path of try_atomic_semop()] can be in the same cacheline. Signed-off-by: Manfred Spraul Cc: Chris Mason Cc: Zach Brown Cc: Jens Axboe Cc: Nick Piggin Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

ipc/sem.c: add a per-semaphore pending list

2009-12-16T15:20:10Z

Based on Nick's findings: sysv sem has the concept of semaphore arrays that consist out of multiple semaphores. Atomic operations that affect multiple semaphores are supported. The patch is the first step for optimizing simple, single semaphore operations: In addition to the global list of all pending operations, a 2nd, per-semaphore list with the simple operations is added. Note: this patch does not make sense by itself, the new list is used nowhere. Signed-off-by: Manfred Spraul Cc: Nick Piggin Cc: Pierre Peiffer Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

ipc/sem.c: rewrite undo list locking

2008-07-25T17:53:42Z

The attached patch: - reverses the locking order of ulp->lock and sem_lock: Previously, it was first ulp->lock, then inside sem_lock. Now it's the other way around. - converts the undo structure to rcu. Benefits: - With the old locking order, IPC_RMID could not kfree the undo structures. The stale entries remained in the linked lists and were released later. - The patch fixes a a race in semtimedop(): if both IPC_RMID and a semget() that recreates exactly the same id happen between find_alloc_undo() and sem_lock, then semtimedop() would access already kfree'd memory. [akpm@linux-foundation.org: coding-style fixes] Signed-off-by: Manfred Spraul Reviewed-by: Nadia Derbey Cc: Pierre Peiffer Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

ipc/sem.c: convert sem_array.sem_pending to struct list_head

2008-07-25T17:53:42Z

sem_array.sem_pending is a double linked list, the attached patch converts it to struct list_head. [akpm@linux-foundation.org: coding-style fixes] Signed-off-by: Manfred Spraul Reviewed-by: Nadia Derbey Cc: Pierre Peiffer Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

ipc/sem.c: remove unused entries from struct sem_queue

2008-07-25T17:53:42Z

sem_queue.sma and sem_queue.id were never used, the attached patch removes them. Signed-off-by: Manfred Spraul Reviewed-by: Nadia Derbey Cc: Pierre Peiffer Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

ipc/sem.c: convert undo structures to struct list_head

2008-07-25T17:53:42Z

The undo structures contain two linked lists, the attached patch replaces them with generic struct list_head lists. [akpm@linux-foundation.org: coding-style fixes] Signed-off-by: Manfred Spraul Cc: Nadia Derbey Cc: Pierre Peiffer Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

ipc: store ipcs into IDRs

2007-10-19T18:53:44Z

This patch introduces ipcs storage into IDRs. The main changes are: . This ipc_ids structure is changed: the entries array is changed into a root idr structure. . The grow_ary() routine is removed: it is not needed anymore when adding an ipc structure, since we are now using the IDR facility. . The ipc_rmid() routine interface is changed: . there is no need for this routine to return the pointer passed in as argument: it is now declared as a void . since the id is now part of the kern_ipc_perm structure, no need to have it as an argument to the routine Signed-off-by: Nadia Derbey Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds