[dpdk-dev] [PATCH v9 2/3] devtools: prevent use of rte atomic APIs in future patches

[Phil Yang]

In order to deprecate the rte_atomic and rte_smp barrier APIs, prevent
the patches from using these APIs and __sync builtins in new code.

On x86 the __atomic_thread_fence(__ATOMIC_SEQ_CST) is quite expensive
for SMP case. Flag the new code which use __atomic_thread_fence API.

Signed-off-by: Phil Yang <phil.yang at arm.com>
Reviewed-by: Ruifeng Wang <ruifeng.wang at arm.com>
---
 devtools/checkpatches.sh | 35 +++++++++++++++++++++++++++++++++++
 1 file changed, 35 insertions(+)

diff --git a/devtools/checkpatches.sh b/devtools/checkpatches.sh
index 58021aa..990a4d0 100755
--- a/devtools/checkpatches.sh
+++ b/devtools/checkpatches.sh
@@ -77,6 +77,41 @@ check_forbidden_additions() { # <patch>
 		-f $(dirname $(readlink -f $0))/check-forbidden-tokens.awk \
 		"$1" || res=1
 
+	# refrain from new additions of 16/32/64 bits rte_atomic_xxx()
+	# multiple folders and expressions are separated by spaces
+	awk -v FOLDERS="lib drivers app examples" \
+		-v EXPRESSIONS="rte_atomic[0-9][0-9]_.*\\\(" \
+		-v RET_ON_FAIL=1 \
+		-v MESSAGE='Using rte_atomicNN_xxx' \
+		-f $(dirname $(readlink -f $0))/check-forbidden-tokens.awk \
+		"$1" || res=1
+
+	# refrain from new additions of rte_smp_XXmb()
+	# multiple folders and expressions are separated by spaces
+	awk -v FOLDERS="lib drivers app examples" \
+		-v EXPRESSIONS="rte_smp_(r|w)?mb\\\(" \
+		-v RET_ON_FAIL=1 \
+		-v MESSAGE='Using rte_smp_[r/w]mb' \
+		-f $(dirname $(readlink -f $0))/check-forbidden-tokens.awk \
+		"$1" || res=1
+
+	# refrain from using compiler __sync builtins
+	awk -v FOLDERS="lib drivers app examples" \
+		-v EXPRESSIONS="__sync_.*\\\(" \
+		-v RET_ON_FAIL=1 \
+		-v MESSAGE='Using __sync_xxx builtins' \
+		-f $(dirname $(readlink -f $0))/check-forbidden-tokens.awk \
+		"$1" || res=1
+
+	# refrain from using compiler __atomic_thread_fence()
+	# It should be avoided on x86 for SMP case.
+	awk -v FOLDERS="lib drivers app examples" \
+		-v EXPRESSIONS="__atomic_thread_fence\\\(" \
+		-v RET_ON_FAIL=1 \
+		-v MESSAGE='Using __atomic_thread_fence' \
+		-f $(dirname $(readlink -f $0))/check-forbidden-tokens.awk \
+		"$1" || res=1
+
 	# svg figures must be included with wildcard extension
 	# because of png conversion for pdf docs
 	awk -v FOLDERS='doc' \
-- 
2.7.4