From mboxrd@z Thu Jan  1 00:00:00 1970
From: Marvin Liu <yong.liu@intel.com>
Subject: [PATCH] mk: using initial-exec model for thread local
	variable
Date: Sat, 28 Apr 2018 17:54:07 +0800
Message-ID: <1524909247-6581-1-git-send-email-yong.liu@intel.com>
Cc: Marvin Liu <yong.liu@intel.com>
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When building share library, thread-local storage model will be changed
to global-dynamic. It will cost additional protect for read thread local
variable. By now only lcore id is this kind of varaible and not need to
dynamic share with other threads. So make TLS model back to initial-exec
like static library for better performance.

Signed-off-by: Marvin Liu <yong.liu@intel.com>

diff --git a/mk/toolchain/gcc/rte.vars.mk b/mk/toolchain/gcc/rte.vars.mk
index 7e4531b..7b5e71c 100644
--- a/mk/toolchain/gcc/rte.vars.mk
+++ b/mk/toolchain/gcc/rte.vars.mk
@@ -43,6 +43,10 @@ ifeq (,$(findstring -O0,$(EXTRA_CFLAGS)))
 endif
 endif
 
+ifeq ($(CONFIG_RTE_BUILD_SHARED_LIB),y)
+TOOLCHAIN_CFLAGS += -ftls-model=initial-exec
+endif
+
 WERROR_FLAGS := -W -Wall -Wstrict-prototypes -Wmissing-prototypes
 WERROR_FLAGS += -Wmissing-declarations -Wold-style-definition -Wpointer-arith
 WERROR_FLAGS += -Wcast-align -Wnested-externs -Wcast-qual
-- 
1.9.3