Tests: Add test for byte/short atomics on addresses which are not word-aligned

[userspace-rcu.git] / README.md

diff --git a/README.md b/README.md
index 6b87b63719aa03eaa57d01a6bc671624bafd7c1f..1f7aaaf258db7118e3900a2e7a740048bb6f63c3 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
 ============================
 
@@ -164,7 +170,6 @@ There are multiple flavors of liburcu available:
   - `memb`,
   - `qsbr`,
   - `mb`,
-  - `signal`,
   - `bp`.
 
 The API members start with the prefix `urcu_<flavor>_`, where
@@ -209,15 +214,6 @@ and reader sides. This results in faster grace-period detection, but
 results in slower reads.
 
 
-### Usage of `liburcu-signal`
-
-  1. `#include <urcu/urcu-signal.h>`
-  2. 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`
 
   1. `#include <urcu/urcu-bp.h>`
@@ -267,7 +263,7 @@ the grace period has completed, false otherwise.
 ### Usage of `liburcu-defer`
 
   - Follow instructions for either `liburcu-memb`, `liburcu-qsbr`,
-    `liburcu-mb`, `liburcu-signal`, or `liburcu-bp` above.
+    `liburcu-mb`, or `liburcu-bp` above.
     The `liburcu-defer` functionality is pulled into each of
     those library modules.
   - Provides `urcu_<flavor>_defer_rcu()` primitive to enqueue delayed
@@ -286,7 +282,7 @@ Its API is currently experimental. It may change in future library releases.
 ### Usage of `urcu-call-rcu`
 
   - Follow instructions for either `liburcu-memb`, `liburcu-qsbr`,
-    `liburcu-mb`, `liburcu-signal`, or `liburcu-bp` above.
+    `liburcu-mb`, or `liburcu-bp` above.
     The `urcu-call-rcu` functionality is pulled into each of
     those library modules.
   - Provides the `urcu_<flavor>_call_rcu()` primitive to enqueue delayed
@@ -304,13 +300,6 @@ Its API is currently experimental. It may change in future library releases.
 
 ### Being careful with signals
 
-The `liburcu-signal` library uses signals internally. The signal handler is
-registered with the `SA_RESTART` flag. However, these signals may cause
-some non-restartable system calls to fail with `errno = EINTR`. Care
-should be taken to restart system calls manually if they fail with this
-error. A list of non-restartable system calls may be found in
-`signal(7)`.
-
 Read-side critical sections are allowed in a signal handler,
 except those setup with `sigaltstack(2)`, with `liburcu-memb` and
 `liburcu-mb`. Be careful, however, to disable these signals
@@ -434,6 +423,10 @@ 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.
 
+### 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
 ------------