configure: Add --enable-compiler-atomic-builtins option

[urcu.git] / README.md

diff --git a/README.md b/README.md
index cd24cc53ba0f3887d08c467be033f2e6af6f661d..d7966a2c54dbbad4eaf92a5e01b8d99abd7e6451 100644 (file)
--- a/README.md
+++ b/README.md
@@ -1,3 +1,9 @@
+<!--
+SPDX-FileCopyrightText: 2023 EfficiOS Inc.
+
+SPDX-License-Identifier: CC-BY-4.0
+-->
+

 Userspace RCU Implementation
 ============================
 
 Userspace RCU Implementation
 ============================
 


@@ -55,8 +61,7 @@ Currently, the following architectures are supported:
 Tested on:
 
   - Linux all architectures
 Tested on:
 
   - Linux all architectures

-  - FreeBSD 8.2/8.3/9.0/9.1/10.0 i386/amd64
-  - Solaris 10/11 i386
+  - FreeBSD 13 i386/amd64

   - Cygwin i386/amd64
   - MacOS amd64/arm64
 
   - Cygwin i386/amd64
   - MacOS amd64/arm64
 


@@ -65,18 +70,19 @@ Should also work on:
   - Android
   - NetBSD 5
   - OpenBSD
   - Android
   - NetBSD 5
   - OpenBSD

-  - Darwin
+  - Solaris

 
 (more testing needed before claiming support for these OS).
 
 
 (more testing needed before claiming support for these OS).
 

-Linux ARM depends on running a Linux kernel 2.6.15 or better, GCC 4.4 or
-better.

 
 

-The C compiler used needs to support at least C99. The C++ compiler used
-needs to support at least C++11.
+Toolchain support
+-----------------

 
 

-The GCC compiler versions 3.3, 3.4, 4.0, 4.1, 4.2, 4.3, 4.4 and 4.5 are
-supported, with the following exceptions:
+The C compiler used needs to support at least C99. The C++ compiler used needs
+to support at least C++11. The oldest GCC version officialy supported and
+tested is 4.8.
+
+Older GCC versions might still work with the following exceptions:

 
   - GCC 3.3 and 3.4 have a bug that prevents them from generating volatile
     accesses to offsets in a TLS structure on 32-bit x86. These versions are
 
   - GCC 3.3 and 3.4 have a bug that prevents them from generating volatile
     accesses to offsets in a TLS structure on 32-bit x86. These versions are


@@ -97,6 +103,10 @@ Clang version 3.0 (based on LLVM 3.0) is supported.
 Glibc >= 2.4 should work but the older version we test against is
 currently 2.17.
 
 Glibc >= 2.4 should work but the older version we test against is
 currently 2.17.
 

+
+Build system
+------------
+

 For developers using the Git tree:
 
 This source tree is based on the autotools suite from GNU to simplify
 For developers using the Git tree:
 
 This source tree is based on the autotools suite from GNU to simplify


@@ -251,6 +261,14 @@ protected pointer.
 After, `urcu_<flavor>_synchronize_rcu()` must be called. When it
 returns, the old values are not in usage anymore.
 
 After, `urcu_<flavor>_synchronize_rcu()` must be called. When it
 returns, the old values are not in usage anymore.
 

+As an alternative to `urcu_<flavor>_synchronize_rcu()`,
+it is also possible to use the urcu polling mechanism to wait for a
+grace period to elapse. This can be done by using
+`urcu_<flavor>_start_poll_synchronize_rcu()`
+to start the grace period polling, and then invoke
+`urcu_<flavor>_poll_state_synchronize_rcu()`, which returns true if
+the grace period has completed, false otherwise.
+

 
 ### Usage of `liburcu-defer`
 
 
 ### Usage of `liburcu-defer`
 


@@ -422,6 +440,10 @@ still being used to iterate on a hash table.
 This option alters the rculfhash ABI. Make sure to compile both library
 and application with matching configuration.
 
 This option alters the rculfhash ABI. Make sure to compile both library
 and application with matching configuration.
 

+### Usage of `--enable-compiler-atomic-builtins`
+
+Building liburcu with `--enable-compiler-atomic-builtins` implements the uatomic
+API with the compiler atomic builtins if supported.

 
 Make targets
 ------------
 
 Make targets
 ------------