diff options
Diffstat (limited to 'src/include/sys/sync.h')
| -rw-r--r-- | src/include/sys/sync.h | 90 |
1 files changed, 64 insertions, 26 deletions
diff --git a/src/include/sys/sync.h b/src/include/sys/sync.h index 58e5c9327..1463b3f6f 100644 --- a/src/include/sys/sync.h +++ b/src/include/sys/sync.h @@ -1,25 +1,25 @@ -// IBM_PROLOG_BEGIN_TAG -// This is an automatically generated prolog. -// -// $Source: src/include/sys/sync.h $ -// -// IBM CONFIDENTIAL -// -// COPYRIGHT International Business Machines Corp. 2011 -// -// p1 -// -// Object Code Only (OCO) source materials -// Licensed Internal Code Source Materials -// IBM HostBoot Licensed Internal Code -// -// The source code for this program is not published or other- -// wise divested of its trade secrets, irrespective of what has -// been deposited with the U.S. Copyright Office. -// -// Origin: 30 -// -// IBM_PROLOG_END +/* IBM_PROLOG_BEGIN_TAG */ +/* This is an automatically generated prolog. */ +/* */ +/* $Source: src/include/sys/sync.h $ */ +/* */ +/* IBM CONFIDENTIAL */ +/* */ +/* COPYRIGHT International Business Machines Corp. 2011,2012 */ +/* */ +/* p1 */ +/* */ +/* Object Code Only (OCO) source materials */ +/* Licensed Internal Code Source Materials */ +/* IBM HostBoot Licensed Internal Code */ +/* */ +/* The source code for this program is not published or otherwise */ +/* divested of its trade secrets, irrespective of what has been */ +/* deposited with the U.S. Copyright Office. */ +/* */ +/* Origin: 30 */ +/* */ +/* IBM_PROLOG_END_TAG */ #ifndef SYNC #define SYNC @@ -33,7 +33,7 @@ struct _futex_imp_t uint64_t iv_val; }; -typedef _futex_imp_t mutex_t; +typedef _futex_imp_t mutex_t; /** * Barrier object type @@ -53,7 +53,7 @@ typedef _barrier_imp_t barrier_t; /** * Conditional variable types */ -struct _cond_imp_t +struct _cond_imp_t { mutex_t * mutex; uint64_t sequence; @@ -83,7 +83,7 @@ void barrier_init (barrier_t * o_barrier, uint64_t i_count); /** - * @fn barrier_destroy + * @fn barrier_destroy * @brief Destroy a barrier * @param[in] i_barrier The barrier */ @@ -167,7 +167,7 @@ int sync_cond_wait(sync_cond_t * i_cond, mutex_t * i_mutex); * @pre This task must hold the lock on the mutex used in sync_cond_wait() * @pre sync_cond_wait() must have been called for conditional variable * @note failing to unlock the mutex after this call may cause the waiting - * task to remain blocked. If there is more than one task waiting on the + * task to remain blocked. If there is more than one task waiting on the * conditional variable then sync_cond_broadcast() should be used instead. */ void sync_cond_signal(sync_cond_t * i_cond); @@ -183,4 +183,42 @@ void sync_cond_signal(sync_cond_t * i_cond); */ void sync_cond_broadcast(sync_cond_t * i_cond); +/** @fn futex_wait + * @brief Perform a futex-wait operation. + * + * This system call is modeled after 'futex' under Linux. + * + * Will block the user space application until an address is signaled + * for waking. In order to prevent deadlock conditions where the address + * has already changed while the system-call is being processed, the + * address is checked against the currently known value. If the value has + * already changed then the function immediately returns. + * + * @param[in] i_addr - Address to wait for signal on. + * @param[in] i_val - Current value at that address. + * + * @return SUCCESS or EWOULDBLOCK. + * + * A return of EWOULDBLOCK indicates that *i_addr != i_val. + */ +int futex_wait(uint64_t * i_addr, uint64_t i_val); + +/** @fn futex_wake + * @brief Peform a futex-wake operation. + * + * This system call is modeled after 'futex' under Linux. + * + * Will awaken a number of tasks currently waiting to be signalled for an + * address. + * + * @param[in] i_addr - The address to signal. + * @param[in] i_count - The maximum number of tasks to awaken. + * + * @return SUCCESS. + * + * If less tasks than i_count are currently blocked, all blocked tasks will + * be awoken. + */ +int futex_wake(uint64_t * i_addr, uint64_t i_count); + #endif |
