Subject: + ipc-semc-rename-try_atomic_semop-to-perform_atomic_semop-docu-update.patch added to -mm tree
To: manfred@xxxxxxxxxxxxxxxx,davidlohr.bueso@xxxxxx,riel@xxxxxxxxxx
From: akpm@xxxxxxxxxxxxxxxxxxxx
Date: Thu, 30 May 2013 14:13:52 -0700
The patch titled
Subject: ipc/sem.c: rename try_atomic_semop() to perform_atomic_semop(), docu update
has been added to the -mm tree. Its filename is
ipc-semc-rename-try_atomic_semop-to-perform_atomic_semop-docu-update.patch
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------------------------------------------------------
From: Manfred Spraul <manfred@xxxxxxxxxxxxxxxx>
Subject: ipc/sem.c: rename try_atomic_semop() to perform_atomic_semop(), docu update
Final cleanup: Some minor points that I noticed while writing the
previous 3 patches
1) The name try_atomic_semop() is misleading: The function performs the
operation (if it is possible).
2) Some documentation updates.
No real code change, a rename and documentation changes.
Signed-off-by: Manfred Spraul <manfred@xxxxxxxxxxxxxxxx>
Acked-by: Rik van Riel <riel@xxxxxxxxxx>
Cc: Davidlohr Bueso <davidlohr.bueso@xxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
ipc/sem.c | 32 +++++++++++++++++++++-----------
1 file changed, 21 insertions(+), 11 deletions(-)
diff -puN ipc/sem.c~ipc-semc-rename-try_atomic_semop-to-perform_atomic_semop-docu-update ipc/sem.c
--- a/ipc/sem.c~ipc-semc-rename-try_atomic_semop-to-perform_atomic_semop-docu-update
+++ a/ipc/sem.c
@@ -153,12 +153,15 @@ static int sysvipc_sem_proc_show(struct
#define SEMOPM_FAST 64 /* ~ 372 bytes on stack */
/*
- * linked list protection:
+ * Locking:
* sem_undo.id_next,
+ * sem_array.complex_count,
* sem_array.pending{_alter,_cont},
- * sem_array.sem_undo: sem_lock() for read/write
+ * sem_array.sem_undo: global sem_lock() for read/write
* sem_undo.proc_next: only "current" is allowed to read/write that field.
*
+ * sem_array.sem_base[i].pending_{const,alter}:
+ * global or semaphore sem_lock() for read/write
*/
#define sc_semmsl sem_ctls[0]
@@ -537,12 +540,19 @@ SYSCALL_DEFINE3(semget, key_t, key, int,
return ipcget(ns, &sem_ids(ns), &sem_ops, &sem_params);
}
-/*
- * Determine whether a sequence of semaphore operations would succeed
- * all at once. Return 0 if yes, 1 if need to sleep, else return error code.
+/** perform_atomic_semop - Perform (if possible) a semaphore operation
+ * @sma: semaphore array
+ * @sops: array with operations that should be checked
+ * @nsems: number of sops
+ * @un: undo array
+ * @pid: pid that did the change
+ *
+ * Returns 0 if the operation was possible.
+ * Returns 1 if the operation is impossible, the caller must sleep.
+ * Negative values are error codes.
*/
-static int try_atomic_semop (struct sem_array * sma, struct sembuf * sops,
+static int perform_atomic_semop(struct sem_array *sma, struct sembuf *sops,
int nsops, struct sem_undo *un, int pid)
{
int result, sem_op;
@@ -725,8 +735,8 @@ static int wake_const_ops(struct sem_arr
q = container_of(walk, struct sem_queue, list);
walk = walk->next;
- error = try_atomic_semop(sma, q->sops, q->nsops,
- q->undo, q->pid);
+ error = perform_atomic_semop(sma, q->sops, q->nsops,
+ q->undo, q->pid);
if (error <= 0) {
/* operation completed, remove from queue & wakeup */
@@ -837,7 +847,7 @@ again:
if (semnum != -1 && sma->sem_base[semnum].semval == 0)
break;
- error = try_atomic_semop(sma, q->sops, q->nsops,
+ error = perform_atomic_semop(sma, q->sops, q->nsops,
q->undo, q->pid);
/* Does q->sleeper still need to sleep? */
@@ -1664,7 +1674,6 @@ static int get_queue_result(struct sem_q
return error;
}
-
SYSCALL_DEFINE4(semtimedop, int, semid, struct sembuf __user *, tsops,
unsigned, nsops, const struct timespec __user *, timeout)
{
@@ -1762,7 +1771,8 @@ SYSCALL_DEFINE4(semtimedop, int, semid,
if (un && un->semid == -1)
goto out_unlock_free;
- error = try_atomic_semop (sma, sops, nsops, un, task_tgid_vnr(current));
+ error = perform_atomic_semop(sma, sops, nsops, un,
+ task_tgid_vnr(current));
if (error <= 0) {
if (alter && error == 0)
do_smart_update(sma, sops, nsops, 1, &tasks);
_
Patches currently in -mm which might be from manfred@xxxxxxxxxxxxxxxx are
ipc-sem-seperate-wait-for-zero-and-alter-tasks-into-seperate-queues.patch
ipc-semc-always-use-only-one-queue-for-alter-operations.patch
ipc-semc-rename-try_atomic_semop-to-perform_atomic_semop-docu-update.patch
slab-leaks3-default-y.patch
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