From: Steven Lariau <steven.lariau@arm.com> To: Gage Eads <gage.eads@intel.com>, Olivier Matz <olivier.matz@6wind.com> Cc: dev@dpdk.org, nd@arm.com, Steven Lariau <steven.lariau@arm.com> Subject: [dpdk-dev] [PATCH v2 2/5] lib/stack: remove push acquire fence Date: Fri, 25 Sep 2020 18:43:36 +0100 Message-ID: <20200925174340.10014-3-steven.lariau@arm.com> (raw) In-Reply-To: <20200925174340.10014-1-steven.lariau@arm.com> An acquire fence is used to make sure loads after the fence can observe all store operations before a specific store-release. But push doesn't read any data, except for the head which is part of a CAS operation (the items on the list are not read). So there is no need for the acquire barrier. Signed-off-by: Steven Lariau <steven.lariau@arm.com> Reviewed-by: Dharmik Thakkar <dharmik.thakkar@arm.com> Reviewed-by: Ruifeng Wang <ruifeng.wang@arm.com> Acked-by: Gage Eads <gage.eads@intel.com> --- lib/librte_stack/rte_stack_lf_c11.h | 6 ------ 1 file changed, 6 deletions(-) diff --git a/lib/librte_stack/rte_stack_lf_c11.h b/lib/librte_stack/rte_stack_lf_c11.h index 1e0ea0bef..82b7287f1 100644 --- a/lib/librte_stack/rte_stack_lf_c11.h +++ b/lib/librte_stack/rte_stack_lf_c11.h @@ -44,12 +44,6 @@ __rte_stack_lf_push_elems(struct rte_stack_lf_list *list, do { struct rte_stack_lf_head new_head; - /* Use an acquire fence to establish a synchronized-with - * relationship between the list->head load and store-release - * operations (as part of the rte_atomic128_cmp_exchange()). - */ - __atomic_thread_fence(__ATOMIC_ACQUIRE); - /* Swing the top pointer to the first element in the list and * make the last element point to the old top. */ -- 2.17.1
next prev parent reply other threads:[~2020-09-25 17:44 UTC|newest] Thread overview: 22+ messages / expand[flat|nested] mbox.gz Atom feed top 2020-09-11 15:29 [dpdk-dev] [PATCH 0/5] lib/stack: improve lockfree C11 implementation Steven Lariau 2020-09-11 15:29 ` [dpdk-dev] [PATCH 1/5] lib/stack: fix inconsistent weak / strong cas Steven Lariau 2020-09-21 17:16 ` Eads, Gage 2020-09-11 15:29 ` [dpdk-dev] [PATCH 2/5] lib/stack: remove push acquire fence Steven Lariau 2020-09-21 17:16 ` Eads, Gage 2020-09-11 15:29 ` [dpdk-dev] [PATCH 3/5] lib/stack: remove redundant orderings for list->len Steven Lariau 2020-09-21 17:16 ` Eads, Gage 2020-09-11 15:29 ` [dpdk-dev] [PATCH 4/5] lib/stack: reload head when pop fails Steven Lariau 2020-09-21 17:16 ` Eads, Gage 2020-09-11 15:29 ` [dpdk-dev] [PATCH 5/5] lib/stack: remove pop cas release ordering Steven Lariau 2020-09-21 17:17 ` Eads, Gage 2020-09-25 14:27 ` David Marchand 2020-09-25 17:43 ` [dpdk-dev] [PATCH v2 0/5] lib/stack: improve lockfree C11 implementation Steven Lariau 2020-09-25 17:43 ` [dpdk-dev] [PATCH v2 1/5] lib/stack: fix inconsistent weak / strong cas Steven Lariau 2020-09-28 10:22 ` David Marchand 2020-09-28 15:58 ` Eads, Gage 2020-09-25 17:43 ` Steven Lariau [this message] 2020-09-25 17:43 ` [dpdk-dev] [PATCH v2 3/5] lib/stack: remove redundant orderings for list->len Steven Lariau 2020-09-25 17:43 ` [dpdk-dev] [PATCH v2 4/5] lib/stack: reload head when pop fails Steven Lariau 2020-09-25 17:43 ` [dpdk-dev] [PATCH v2 5/5] lib/stack: remove pop cas release ordering Steven Lariau 2020-09-25 17:57 ` Eads, Gage 2020-09-30 19:14 ` [dpdk-dev] [PATCH v2 0/5] lib/stack: improve lockfree C11 implementation David Marchand
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=20200925174340.10014-3-steven.lariau@arm.com \ --to=steven.lariau@arm.com \ --cc=dev@dpdk.org \ --cc=gage.eads@intel.com \ --cc=nd@arm.com \ --cc=olivier.matz@6wind.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
DPDK patches and discussions This inbox may be cloned and mirrored by anyone: git clone --mirror https://inbox.dpdk.org/dev/0 dev/git/0.git # If you have public-inbox 1.1+ installed, you may # initialize and index your mirror using the following commands: public-inbox-init -V2 dev dev/ https://inbox.dpdk.org/dev \ dev@dpdk.org public-inbox-index dev Example config snippet for mirrors. Newsgroup available over NNTP: nntp://inbox.dpdk.org/inbox.dpdk.dev AGPL code for this site: git clone https://public-inbox.org/public-inbox.git