plockstat
Reader/Writer Lock Probes
Reader/writer locks enable multiple readers or a single writer, but not both, to be in a critical section at one time. These locks are typically used for structures that are searched more frequently than they are modified, or when threads spend substantial time in a critical section. Users interact with reader/writer locks using the Oracle Solaris rwlock
or POSIX pthread_rwlock_init
interfaces.
The probes pertaining to readers/writer locks are described in the
following list. For each probe, arg0
contains a
pointer to the rwlock_t
or
pthread_rwlock_t
structure that
represents the adaptive lock. arg1
contains a
boolean value that indicates whether the operation was as a
writer.
-
rw-acquire
-
Hold event probe that fires immediately after a readers/writer lock is acquired.
-
rw-block
-
Contention event probe that fires before a thread blocks while attempting to acquire a lock. If enabled, the
rw-acquire
probe or therw-error
probe will fire afterrw-block
. -
rw-error
-
Error event probe that fires when an error is encountered during a reader/writer lock operation.
arg1
is theerrno
value of the error encountered. -
rw-release
-
Hold event probe that fires immediately after a reader/writer lock is released.