<html><body><div style="font-family: arial, helvetica, sans-serif; font-size: 12pt; color: #000000"><div>Hi,</div><div><br data-mce-bogus="1"></div><div>There is no "write_lock" in RCU per se. The update side uses a synchronize_rcu() instead.<br></div><div><br data-mce-bogus="1"></div><div>Yes, there can be interference between multiple shared resources using the same liburcu<br data-mce-bogus="1"></div><div>flavor. Very long read-side critical sections can delay completion of synchronize_rcu.<br data-mce-bogus="1"></div><div><br data-mce-bogus="1"></div><div>I've done prototypes of liburcu flavors that have a "domain" structure, thus allowing each<br data-mce-bogus="1"></div><div>liburcu users to have their own grace period domain, but never had time to complete it and<br data-mce-bogus="1"></div><div>get it upstream.<br data-mce-bogus="1"></div><div><br data-mce-bogus="1"></div><div>Thanks,<br data-mce-bogus="1"></div><div><br data-mce-bogus="1"></div><div>Mathieu<br data-mce-bogus="1"></div><div><style style="display:none;"> P {margin-top:0;margin-bottom:0;} </style></div><div><br></div><div><br></div><div><span id="zwchr" data-marker="__DIVIDER__">----- On Apr 9, 2018, at 2:32 AM, 志昌 余 <yuzhichang_scl@hotmail.com> wrote:<br></span></div><div data-marker="__QUOTED_TEXT__"><blockquote style="border-left:2px solid #1010FF;margin-left:5px;padding-left:5px;color:#000;font-weight:normal;font-style:normal;text-decoration:none;font-family:Helvetica,Arial,sans-serif;font-size:12pt;">
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According to <a href="https://github.com/urcu/userspace-rcu/blob/master/doc/rcu-api.md" id="LPNoLP727713" target="_blank">https://github.com/urcu/userspace-rcu/blob/master/doc/rcu-api.md</a>, none librcu API take the resource address. </div>
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If there're <span style="color: rgb(0, 0, 0); font-family: Calibri, Helvetica, sans-serif; font-size: 12pt;">multiple independent shared resource, seems there's i</span><span style="color: rgb(0, 0, 0); font-family: Calibri, Helvetica, sans-serif; font-size: 12pt;">nterference
between read_lock of </span><span style="color: rgb(0, 0, 0); font-family: Calibri, Helvetica, sans-serif; font-size: 12pt;">resource A and write_lock of resource B.</span></div>
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<br>_______________________________________________<br>lttng-dev mailing list<br>lttng-dev@lists.lttng.org<br>https://lists.lttng.org/cgi-bin/mailman/listinfo/lttng-dev<br></blockquote></div><div><br></div><div data-marker="__SIG_POST__">-- <br></div><div>Mathieu Desnoyers<br>EfficiOS Inc.<br>http://www.efficios.com</div></div></body></html>