All of lore.kernel.org
 help / color / mirror / Atom feed
From: Marvin Liu <yong.liu@intel.com>
To: zhiyong.yang@intel.com, thomas@monjalon.net, dev@dpdk.org
Cc: Marvin Liu <yong.liu@intel.com>
Subject: [PATCH] mk: using initial-exec model for thread local variable
Date: Thu,  5 Jul 2018 22:13:21 +0800	[thread overview]
Message-ID: <20180705141321.129989-1-yong.liu@intel.com> (raw)

When building share library, thread-local storage model will be changed
to global-dynamic. It will add additional cost for reading thread local
variable. On the other hand, dynamically load share library with static
TLS will request additional DTV slot which is limited by loader. By now
only librte_pmd_eal.so contain thread local variable. So that can 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 7e4531bab..19d5e11ef 100644
--- a/mk/toolchain/gcc/rte.vars.mk
+++ b/mk/toolchain/gcc/rte.vars.mk
@@ -43,6 +43,13 @@ ifeq (,$(findstring -O0,$(EXTRA_CFLAGS)))
 endif
 endif
 
+# Initial execution TLS model has better performane compared to dynamic
+# global. But this model require for addtional slot on DTV when dlopen
+# object with thread local variable.
+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
-- 
2.17.0

             reply	other threads:[~2018-07-05  6:27 UTC|newest]

Thread overview: 8+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2018-07-05 14:13 Marvin Liu [this message]
2018-07-05  9:25 ` [PATCH] mk: using initial-exec model for thread local variable Thomas Monjalon
2018-07-05 14:46 ` Sachin Saxena
2018-07-06  2:22   ` Liu, Yong
2018-07-06 10:02     ` Bruce Richardson
  -- strict thread matches above, loose matches on Subject: below --
2018-04-28  9:54 Marvin Liu
2018-04-28  4:39 ` Yang, Zhiyong
2018-05-18  9:46   ` Thomas Monjalon

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20180705141321.129989-1-yong.liu@intel.com \
    --to=yong.liu@intel.com \
    --cc=dev@dpdk.org \
    --cc=thomas@monjalon.net \
    --cc=zhiyong.yang@intel.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body. 
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.