<div dir="ltr"><div><div><div>Check this out:<br><br></div>drivers/infiniband/core/cache.c<br><br></div>function: ib_cache_gid_add<br><br></div>Line: 338 <br><br>mutex_lock(&table->lock);<br> write_lock_irq(&table->rwlock);<br>.<br>.<br>.<br>.<br> write_unlock_irq(&table->rwlock);<br> mutex_unlock(&table->lock);<br></div><div class="gmail_extra"><br><div class="gmail_quote">On Thu, Feb 25, 2016 at 3:42 PM, priyaranjan <span dir="ltr"><<a href="mailto:priyaranjan45678@gmail.com" target="_blank">priyaranjan45678@gmail.com</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><div dir="ltr"><div class="gmail_extra"><div class="gmail_quote"><div><span class=""><div>>On Thu, Feb 25, 2016 at 2:53 PM, Devesh Sharma <<a href="mailto:devesh28@gmail.com" target="_blank">devesh28@gmail.com</a>> wrote:</div></span><span class=""><div>>Hi</div><div><br></div><div>>In running kernel there are many places you can look to get the usage. But the bottom line is</div><div><br></div></span><div>Can you tell me the specific use case? or give me the file name/driver where this is used.</div><span class=""><div><br></div><div>>* You can take a spinlock under a mutex. e.g. mutex_lock--->spinlock-----critical section-----spinunlock--->mutex_unlock.</div><div><br></div><div>>* You can not take a mutex under a spinlock. e.g. spinlock--->mutex_lock -----critical section ....mutex_unlock---->spinunlock is not allowed.</div><div><br></div><div><br></div><div>On Thu, Feb 25, 2016 at 11:37 AM, priyaranjan <<a href="mailto:priyaranjan45678@gmail.com" target="_blank">priyaranjan45678@gmail.com</a>> wrote:</div><div>Hello All,</div><div><br></div><div>Do you have any idea of a situation where we would need mutex and spinlock to be locked together? I think there is an example for this in Linux kernel. Can anyone help me?</div><div><br></div><div>Regards,</div><div>Priyaranjan</div><div><br></div><div>_______________________________________________</div><div>Kernelnewbies mailing list</div><div><a href="mailto:Kernelnewbies@kernelnewbies.org" target="_blank">Kernelnewbies@kernelnewbies.org</a></div><div><a href="http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies" target="_blank">http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies</a></div></span></div><div><br></div><div><br></div><div><br></div></div></div></div>
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