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<div><div style="font-family: 微软雅黑, Tahoma; line-height: normal;">> another question:</div><div style="font-family: 微软雅黑, Tahoma; line-height: normal;">></div><div style="font-family: 微软雅黑, Tahoma; line-height: normal;">> if i use the smp configuration macro define，am i still need to do the</div><div style="font-family: 微软雅黑, Tahoma; line-height: normal;">> mutiprocessor configuration macro define for confdef.h ?</div><div style="font-family: 微软雅黑, Tahoma; line-height: normal;">></div><div style="font-family: 微软雅黑, Tahoma; line-height: normal;">With SMP you have to enable SMP when you configure/build RTEMS, and</div><div style="font-family: 微软雅黑, Tahoma; line-height: normal;">you need to provide the CPP configuration macros to set up the SMP</div><div style="font-family: 微软雅黑, Tahoma; line-height: normal;">system and schedulers.</div></div><div style="font-family: 微软雅黑, Tahoma; line-height: normal;"><br></div><div style="font-family: 微软雅黑, Tahoma; line-height: normal;"><span style="background-color: window; font-size: 10.5pt;">>> what the CPP means? </span></div><div style="font-family: 微软雅黑, Tahoma; line-height: normal;"><span style="background-color: window; font-size: 10.5pt;">>>in </span><span style="font-family: CharterBT-Roman; line-height: 1.5; background-color: window;">CONFIGURING A SYSTEM chapter in c user doc, i find the two configurations items . one is </span><span style="font-family: CharterBT-Roman; font-size: 14pt; line-height: 1.5; background-color: window;">24.22 SMP Specific Configuration Parameters ,another is </span><span style="background-color: window; font-family: CharterBT-Roman; font-size: 14pt; line-height: 1.5;">24.24 Multiprocessing Configuration </span></div><!--StartFragment-->
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<div style="font-family: 微软雅黑, Tahoma; line-height: normal;"><span style="background-color: window; font-size: 10.5pt;">>>what i want to ask is if i want to use smp, do i need use the </span><span style="font-family: CharterBT-Roman; font-size: 19px; line-height: 28px; background-color: window;">Multiprocessing</span><span style="font-family: CharterBT-Roman; font-size: 19px; line-height: 28px; background-color: window;"> </span><span style="font-family: CharterBT-Roman; font-size: 19px; line-height: 28px; background-color: window;">Configuration? or i just need use </span><span style="font-family: CharterBT-Roman; font-size: 19px; line-height: 28px; background-color: window;">SMP Specific Configuration Parameters and do not need care about >>the </span><span style="font-family: CharterBT-Roman; font-size: 19px; line-height: 28px; background-color: window;">Multiprocessing</span><span style="font-family: CharterBT-Roman; font-size: 19px; line-height: 28px; background-color: window;"> </span><span style="font-family: CharterBT-Roman; font-size: 19px; line-height: 28px; background-color: window;">Configuration.</span></div><div style="font-family: 微软雅黑, Tahoma; line-height: normal;"><span style="font-family: CharterBT-Roman; font-size: 19px; line-height: 28px; background-color: window;"><br></span></div><div style="font-family: 微软雅黑, Tahoma; line-height: normal;"><div style="font-family: 微软雅黑; line-height: 21px;">"SMP means all cores are treated equally by the operating system."</div><div style="font-family: 微软雅黑; line-height: 21px;">"AMP means cores are not treated the same by the OS, which can cover a <span style="font-size: 10.5pt; background-color: window;">lot of heterogeneous behavior."</span></div></div><div style="font-family: 微软雅黑, Tahoma; line-height: normal;"><div style="font-family: 微软雅黑; line-height: 21px;">>>i know what you said </div></div><div style="font-family: 微软雅黑, Tahoma; line-height: normal;"><span style="font-size: 10.5pt; background-color: window;">>>so the basic problem which confused me is the difference betweent </span><span style="font-family: CharterBT-Roman; font-size: 19px; line-height: 28px; background-color: window;">Multiprocessing</span><span style="font-family: CharterBT-Roman; font-size: 19px; line-height: 28px; background-color: window;"> </span><span style="font-family: CharterBT-Roman; font-size: 19px; line-height: 28px; background-color: window;">Configuration</span><span style="background-color: window; font-family: CharterBT-Roman; font-size: 19px; line-height: 28px;"> and SMP </span><span style="font-family: CharterBT-Roman; font-size: 19px; line-height: 28px; background-color: window;">Configuration, not the concept of amp and smp</span></div><div style="font-family: 微软雅黑, Tahoma; line-height: normal;"><span style="font-family: CharterBT-Roman; font-size: 19px; line-height: 28px; background-color: window;">>>in my point of view ,no matter AMP or SMP is all called </span><span style="font-family: CharterBT-Roman; font-size: 19px; line-height: 28px; background-color: window;">Multiprocessing</span><span style="font-family: CharterBT-Roman; font-size: 19px; line-height: 28px; background-color: window;"> because they all use the muticore .is it right ? so if i want to use AMP mode ,than i need >>just </span><span style="font-family: CharterBT-Roman; font-size: 19px; line-height: 28px; background-color: window;">Multiprocessing</span><span style="font-family: CharterBT-Roman; font-size: 19px; line-height: 28px; background-color: window;"> </span><span style="font-family: CharterBT-Roman; font-size: 19px; line-height: 28px; background-color: window;">Configuration?</span></div><div style="font-family: 微软雅黑, Tahoma; line-height: normal;"><span style="background-color: window; font-family: CharterBT-Roman; font-size: 19px; line-height: 28px;">>>if i want to use SMP mode</span><span style="font-family: CharterBT-Roman; font-size: 19px; line-height: 28px; background-color: window;">,than i need </span><span style="font-family: CharterBT-Roman; font-size: 19px; line-height: 28px; background-color: window;">Multiprocessing</span><span style="font-family: CharterBT-Roman; font-size: 19px; line-height: 28px; background-color: window;"> </span><span style="font-family: CharterBT-Roman; font-size: 19px; line-height: 28px; background-color: window;">Configuration</span><span style="background-color: window; font-family: CharterBT-Roman; font-size: 19px; line-height: 28px;"> and SMP </span><span style="font-family: CharterBT-Roman; font-size: 19px; line-height: 28px; background-color: window;">Configuration ? </span></div><div style="font-family: 微软雅黑, Tahoma; line-height: normal;"><span style="font-family: CharterBT-Roman; font-size: 19px; line-height: 28px; background-color: window;"> </span></div><div style="font-family: 微软雅黑, Tahoma; line-height: normal;"><div style="font-family: 微软雅黑; line-height: 21px;"><br></div><div style="font-family: 微软雅黑; line-height: 21px;"><span style="font-size: 10.5pt; background-color: window;"><br></span></div><div style="font-family: 微软雅黑; line-height: 21px;"><span style="font-size: 10.5pt; background-color: window;"><br></span></div></div><div style="font-family: 微软雅黑, Tahoma; line-height: normal;"><span style="background-color: window; font-size: 10.5pt;"><br></span></div><hr style="width: 210px; height: 1px;" color="#b5c4df" size="1" align="left">
<div><span><div style="MARGIN: 10px; FONT-FAMILY: verdana; FONT-SIZE: 10pt"><div>bin.wang@qkmtech.com</div></div></span></div>
<blockquote style="margin-top: 0px; margin-bottom: 0px; margin-left: 0.5em;"><div> </div><div style="border:none;border-top:solid #B5C4DF 1.0pt;padding:3.0pt 0cm 0cm 0cm"><div style="PADDING-RIGHT: 8px; PADDING-LEFT: 8px; FONT-SIZE: 12px;FONT-FAMILY:tahoma;COLOR:#000000; BACKGROUND: #efefef; PADDING-BOTTOM: 8px; PADDING-TOP: 8px"><div><b>From:</b> <a href="mailto:gedare@rtems.org">Gedare Bloom</a></div><div><b>Date:</b> 2018-01-11 00:43</div><div><b>To:</b> <a href="mailto:bin.wang@qkmtech.com">bin.wang@qkmtech.com</a></div><div><b>CC:</b> <a href="mailto:chrisj@rtems.org">Chris Johns</a>; <a href="mailto:users@rtems.org">Users</a></div><div><b>Subject:</b> Re: Re: smp support</div></div></div><div><div>On Fri, Dec 29, 2017 at 3:55 AM, bin.wang@qkmtech.com</div>
<div><bin.wang@qkmtech.com> wrote:</div>
<div>> thanks</div>
<div>></div>
<div>> but i still confused about the smp configuration and the mutiprocessor</div>
<div>> configuration .</div>
<div>></div>
<div>> for example. for zynq ,they has two arm core. if i use the mutiprocessor</div>
<div>> configuration ， Is rtems use the two cores in amp mode ? is the rtems</div>
<div>> manage the two cores？ if rtems manages two cores，i think it is in smp mode</div>
<div>> because i think the concept of smp mode is the one system can manage</div>
<div>> muticores which are same cpu architecture。this is conflictive for my point</div>
<div>> of view</div>
<div>></div>
<div>SMP means all cores are treated equally by the operating system.</div>
<div> </div>
<div>AMP means cores are not treated the same by the OS, which can cover a</div>
<div>lot of heterogeneous behavior.</div>
<div> </div>
<div>RTEMS provides SMP capability.</div>
<div> </div>
<div>> i think amp mode is rtems run in one core, another core is bare-metal or</div>
<div>> linux. but the mutiprocessor configuration let me confused, it said as</div>
<div>> follows</div>
<div>></div>
<div>> "The RTEMS multiprocessor execution model is multiple instruction streams</div>
<div>> with multiple data</div>
<div>> streams (MIMD). This execution model has each of the processors executing</div>
<div>> code independent</div>
<div>> of the other processors. Because of this parallelism, the application</div>
<div>> designer can more easily</div>
<div>> guarantee deterministic behavior."</div>
<div>></div>
<div>This statement is true regardless of SMP/AMP: in either case, program</div>
<div>code runs independent of other processors.</div>
<div> </div>
<div>> is it means one rtems system instance run in one core ,and another rtems</div>
<div>> system instance run in another core? and they can excute code independent?</div>
<div>> sorry, i think maybe i have some concept confused</div>
<div>></div>
<div>One RTEMS instances executes across both cores, and both cores can</div>
<div>execute code independent. It is possible for both cores to be</div>
<div>executing OS functions simultaneously, or one core to execute OS code</div>
<div>while another runs application, or both cores to execute application</div>
<div>code in parallel.</div>
<div> </div>
<div>> if just one rtems run in two core , how to put code into different core to</div>
<div>> run ? how to realize the parrallelism?</div>
<div>></div>
<div>If you select RTEMS with SMP and provide scheduler with two cores, the</div>
<div>scheduler will assign tasks/threads to the cores according to its</div>
<div>scheduler policy/algorithm.</div>
<div> </div>
<div>> another question:</div>
<div>></div>
<div>> if i use the smp configuration macro define，am i still need to do the</div>
<div>> mutiprocessor configuration macro define for confdef.h ?</div>
<div>></div>
<div>With SMP you have to enable SMP when you configure/build RTEMS, and</div>
<div>you need to provide the CPP configuration macros to set up the SMP</div>
<div>system and schedulers.</div>
<div> </div>
<div>> ________________________________</div>
<div>> bin.wang@qkmtech.com</div>
<div>></div>
<div>></div>
<div>> From: Chris Johns</div>
<div>> Date: 2017-12-29 14:21</div>
<div>> To: bin.wang@qkmtech.com; Users</div>
<div>> Subject: Re: smp support</div>
<div>> On 29/12/17 12:16 pm, bin.wang@qkmtech.com wrote:</div>
<div>>> thanks a lot .</div>
<div>>></div>
<div>>> i have another question , if i use the smp, can i use the interrupt of</div>
<div>>> rtems?</div>
<div>>> which i want to interrupt period of hard real time of 125us.</div>
<div>>></div>
<div>></div>
<div>> Yes you can.</div>
<div>></div>
<div>>> i do not know the difference of the bare-metal interrupt and the rtems</div>
<div>>> interrupt</div>
<div>>> . is the rtems interrupt have performance loss of the hard real-time?</div>
<div>></div>
<div>> The interrupt overhead will have the same overhead each time and its</div>
<div>> deterministic behaviour will depend on the other interrupts in your system</div>
<div>> and</div>
<div>> their priority. The performance will depend on what you need to do in the</div>
<div>> interrupt.</div>
<div>></div>
<div>>></div>
<div>>> what the schedule method of smp use? is it can affect the interrupt</div>
<div>>> performance?</div>
<div>>></div>
<div>></div>
<div>> That depends on your application.</div>
<div>></div>
<div>> Chris</div>
<div>></div>
<div>></div>
<div>> _______________________________________________</div>
<div>> users mailing list</div>
<div>> users@rtems.org</div>
<div>> http://lists.rtems.org/mailman/listinfo/users</div>
<div> </div>
</div></blockquote>
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