X-Git-Url: http://git.lttng.org/?a=blobdiff_plain;f=README;h=883b808a3bed372f1dd2597e3e983b9f6c73eae2;hb=24c9669da03d2558d80f4c990539765e887ae010;hp=71eec3530465ebe2093093dce57b4871b0facd66;hpb=9ca52251a7cef5145b29d8b5115785d9f1ec70e3;p=userspace-rcu.git diff --git a/README b/README index 71eec35..883b808 100644 --- a/README +++ b/README @@ -9,11 +9,21 @@ BUILDING 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 + +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 +theoretically work on other operating systems. QUICK START GUIDE ----------------- @@ -89,11 +99,20 @@ Writing Usage of liburcu-defer * #include - * 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 @@ -127,3 +146,13 @@ Usage of DEBUG_YIELD 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.