make
make install
- Note: Forcing 32-bit build:
- * CFLAGS=-m32 ./configure
+ Hints: Forcing 32-bit build:
+ * CFLAGS="-m32 -g -O2" ./configure
Forcing 64-bit build:
- * CFLAGS=-m64 ./configure
+ * CFLAGS="-m64 -g -O2" ./configure
+
+ 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 (only P6+), x86 64, PowerPC 32/64 and S390 are
-supported. The current use of sys_futex() makes it Linux-dependent, although
-this portability limitation might go away in a near future by using the pthread
-cond vars. Also, the restriction against i386, i486 and Pentium might go away if
-we integrate some of glibc runtime CPU-detection tests.
+Currently, x86 (i386, i486, i586, i686), x86 64-bit, PowerPC 32/64, S390, S390x
+and Sparcv9 32/64 are supported. Only tested on Linux so far, but should
+theoretically work on other operating systems.
QUICK START GUIDE
-----------------
* 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.
+ overridden with -DSIGRCU by modifying Makefile.build.inc.
Usage of liburcu-mb
* #include <urcu.h>
- * Compile any _LGPL_SOURCE code using this library with "-DURCU_MB".
+ * Compile any _LGPL_SOURCE code using this library with "-DRCU_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
+ reserve a signal number. RCU_MB uses full memory barriers for
readers. This eliminates the need for signals but results in slower
reads.
* 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.
Usage of liburcu-defer
* #include <urcu-defer.h>
- * Link with "-lurcu-defer"
- * Provides call_rcu() primitive to enqueue delayed callbacks. Queued
+ * Link with "-lurcu-defer", and also with one of the urcu library
+ (either urcu, urcu-bp, urcu-mb or urcu-qsbr).
+ * Provides defer_rcu() primitive to enqueue delayed callbacks. Queued
callbacks are executed in batch periodically after a grace period.
- Do _not_ use call_rcu() within a read-side critical section, because
+ Do _not_ use defer_rcu() within a read-side critical section, because
it may call synchronize_rcu() if the thread queue is full.
+ * Provides defer_rcu_ratelimit() primitive, which acts just like
+ defer_rcu(), but takes an additional rate limiter callback forcing
+ synchronized callback execution of the limiter returns non-zero.
+ * Requires that rcu_defer_barrier() must be called in library destructor
+ if a library queues callbacks and is expected to be unloaded with
+ dlclose().
+ * Its API is currently experimental. It may change in future library
+ releases.
Being careful with signals
DEBUG_YIELD is used to add random delays in the code for testing
purposes.
+
+SMP support
+
+ By default the library is configured to use synchronization primitives
+ adequate for SMP systems. On uniprocessor systems, support for SMP
+ systems can be disabled with:
+
+ ./configure --disable-smp-support
+
+ theoretically yielding slightly better performance.