Forcing a 32-bit build with 386 backward compatibility:
* CFLAGS="-m32 -g -O2" ./configure --host=i386-pc-linux-gnu
+ Forcing a 32-bit build for Sparcv9 (typical for Sparc v9)
+ * CFLAGS="-m32 -Wa,-Av9a -g -O2" ./configure
+
ARCHITECTURES SUPPORTED
-----------------------
Currently, x86 (i386, i486, i586, i686), x86 64-bit, PowerPC 32/64, S390, S390x
-and Sparc64 are supported. Only tested on Linux so far, but should
+and Sparcv9 32/64 are supported. Only tested on Linux so far, but should
theoretically work on other operating systems.
QUICK START GUIDE
* #include <urcu.h>
* Link the application with "-lurcu".
- * This is the preferred version of the library, both in terms of speed
- and flexibility. Requires a signal, typically SIGUSR1. Can be
- overridden with -DSIGURCU by modifying Makefile.build.inc.
-
-Usage of liburcu-mb
-
- * #include <urcu.h>
- * Compile any _LGPL_SOURCE code using this library with "-DURCU_MB".
- * Link with "-lurcu-mb".
- * This version of the urcu library does not need to
- reserve a signal number. URCU_MB uses full memory barriers for
- readers. This eliminates the need for signals but results in slower
- reads.
+ * This is the preferred version of the library, in terms of
+ grace-period detection speed, read-side speed and flexibility.
+ Dynamically detects kernel support for sys_membarrier(). Falls back
+ on urcu-mb scheme if support is not present, which has slower
+ read-side.
Usage of liburcu-qsbr
the threads are not active. It provides the fastest read-side at the
expense of more intrusiveness in the application code.
+Usage of liburcu-mb
+
+ * #include <urcu.h>
+ * Compile any _LGPL_SOURCE code using this library with "-DRCU_MB".
+ * Link with "-lurcu-mb".
+ * This version of the urcu library uses memory barriers on the writer
+ and reader sides. This results in faster grace-period detection, but
+ results in slower reads.
+
+Usage of liburcu-signal
+
+ * #include <urcu-signal.h>
+ * Link the application with "-lurcu-signal".
+ * Version of the library that requires a signal, typically SIGUSR1. Can
+ be overridden with -DSIGRCU by modifying Makefile.build.inc.
+
Usage of liburcu-bp
* #include <urcu-bp.h>
* Link with "-lurcu-bp".
* The BP library flavor stands for "bulletproof". It is specifically
designed to help tracing library to hook on applications without
- requiring to modify these applications. urcu_init(),
+ requiring to modify these applications. rcu_init(),
rcu_register_thread() and rcu_unregister_thread() all become nops.
The state is dealt with by the library internally at the expense of
read-side and write-side performance.
rcu_quiescent_state() calls, when threads are put offline and around
calls to synchronize_rcu(). Even then, we do not recommend it.
+Interaction with mutexes
+
+ One must be careful to do not cause deadlocks due to interaction of
+ synchronize_rcu() and RCU read-side with mutexes. If synchronize_rcu()
+ is called with a mutex held, this mutex (or any mutex which has this
+ mutex in its dependency chain) should not be acquired from within a RCU
+ read-side critical section.
+
Usage of DEBUG_RCU
DEBUG_RCU is used to add internal debugging self-checks to the