From mboxrd@z Thu Jan 1 00:00:00 1970 From: Ferruh Yigit Subject: Re: [PATCH 1/2] eal: add macro to mark variable mostly read only Date: Wed, 18 Apr 2018 18:43:11 +0100 Message-ID: References: <20180418153035.5972-1-pbhagavatula@caviumnetworks.com> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Cc: dev@dpdk.org To: Pavan Nikhilesh , thomas@monjalon.net, jerin.jacob@caviumnetworks.com, techboard@dpdk.org Return-path: In-Reply-To: <20180418153035.5972-1-pbhagavatula@caviumnetworks.com> Content-Language: en-US List-Id: DPDK patches and discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dev-bounces@dpdk.org Sender: "dev" On 4/18/2018 4:30 PM, Pavan Nikhilesh wrote: > Add macro to mark a variable to be mostly read only and place it in a > separate section. > > Signed-off-by: Pavan Nikhilesh > --- > > Group together mostly read only data to avoid cacheline bouncing, also > useful for auditing purposes. > > lib/librte_eal/common/include/rte_common.h | 5 +++++ > 1 file changed, 5 insertions(+) > > diff --git a/lib/librte_eal/common/include/rte_common.h b/lib/librte_eal/common/include/rte_common.h > index 6c5bc5a76..f2ff2e9e6 100644 > --- a/lib/librte_eal/common/include/rte_common.h > +++ b/lib/librte_eal/common/include/rte_common.h > @@ -114,6 +114,11 @@ static void __attribute__((constructor(prio), used)) func(void) > */ > #define __rte_noinline __attribute__((noinline)) > > +/** > + * Mark a variable to be mostly read only and place it in a separate section. > + */ > +#define __rte_read_mostly __attribute__((__section__(".read_mostly"))) Hi Pavan, Is the section ".read_mostly" treated specially [1] or is this just for grouping symbols together (to reduce cacheline bouncing)? [1] If this is special section, can you please point counter part in the kernel? > + > /*********** Macros for pointer arithmetic ********/ > > /** > -- > 2.17.0 >