<html><head><meta http-equiv="Content-Type" content="text/html charset=utf-8"></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;" class=""><div class="">Hello Xiuli,</div><div class=""><br class=""></div><div class="">that’s great news! I tested the OCL20 branch in January. I don’t think it supported SVM atomics then, and I couldn’t get the OCL20 branch to build when I tried again last week. I will make a new attempt next week. You mention the need for an llvm patch to build it - could you tell me which patch that is?</div><div class=""><br class=""></div><div><blockquote type="cite" class=""><div class=""><div class="WordSection1" style="page: WordSection1; font-family: Helvetica; font-size: 12px; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-stroke-width: 0px;"><div style="margin: 0in 0in 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;" class=""><span style="font-size: 11pt; font-family: Calibri, sans-serif; color: rgb(31, 73, 125);" class="">I have some question about the old style way, is the kernel need to be running all the time as the io changes the memory? And do some response to it at a low latency?</span></div></div></div></blockquote><div><br class=""></div><div>That is correct.</div><div><span style="color: rgb(31, 73, 125); font-family: Calibri, sans-serif; font-size: 11pt;" class=""> </span></div><blockquote type="cite" class=""><div class="WordSection1" style="page: WordSection1; font-family: Helvetica; font-size: 12px; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-stroke-width: 0px;"><div style="margin: 0in 0in 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;" class=""><span style="font-size: 11pt; font-family: Calibri, sans-serif; color: rgb(31, 73, 125);" class="">And could you explain the idea about how “invalidate a cache line from the kernel” can help with you requires?</span></div></div></blockquote><div><br class=""></div><div>The idea is to write a loop in opencl which polls a memory location and flushes that memory location from cache so it will be read from system memory each time. But my understanding of the caching and coherence mechanisms involved is not good. Anyway, this point should be moot if you now support SVM atomics.</div><div><br class=""></div><div>Cheers,</div><div><br class=""></div><div>Svein</div><div><br class=""></div></div></body></html>