Gregory Nutt 360539afac Priority inheritance: When CONFIG_SEM_PREALLOCHOLDERS==0, there is only a single, hard-allocated holder structure. This is problem because in sem_wait() the holder is released, but needs to remain in the holder container until sem_restorebaseprio() is called. The call to sem_restorebaseprio() must be one of the last things the sem_wait() does because it can cause the task to be suspended. If in sem_wait(), a new task gets the semaphore count then it will fail to allocate the holder and will not participate in priority inheritance. This fix is to add two hard-allocated holders in the sem_t structure: One of the old holder and one for the new holder.

2017-03-10 09:30:15 -06:00

..

Make.defs

sem_setprotocol: Handle a case of missing proxy for sem_setprotocol. Reorder so that (1) this error is avoided, and (2) >No proxy is needed if priority inheritance is not enabled.

2016-11-03 18:51:38 -06:00

sem_getprotocol.c

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sem_getvalue.c

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sem_init.c

Priority inheritance: When CONFIG_SEM_PREALLOCHOLDERS==0, there is only a single, hard-allocated holder structure. This is problem because in sem_wait() the holder is released, but needs to remain in the holder container until sem_restorebaseprio() is called. The call to sem_restorebaseprio() must be one of the last things the sem_wait() does because it can cause the task to be suspended. If in sem_wait(), a new task gets the semaphore count then it will fail to allocate the holder and will not participate in priority inheritance. This fix is to add two hard-allocated holders in the sem_t structure: One of the old holder and one for the new holder.

2017-03-10 09:30:15 -06:00

sem_setprotocol.c

sem_setprotocol: Handle a case of missing proxy for sem_setprotocol. Reorder so that (1) this error is avoided, and (2) >No proxy is needed if priority inheritance is not enabled.

2016-11-03 18:51:38 -06:00