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<p class=MsoNormal>If anyone is familiar with disksim_cachemem.c, I have a
question regarding the usage of the cache_mem_event structure member lockstop.<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>In the function cachemem_getblock, it is used as:<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>rwdesc->lockstop = - (req->blkno %
cache->atomsperbit);<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>Which would incline me to give it a definition of “Negative
offset from the requested logical block to the lock location for this block”.
In another function allocate_cache_space, it is used as:<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>allocdesc->lockstop = lbn - (lbn % linesize);<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>This would incline me to give it a definition of “Beginning
of the allocation unit for the specified logical block number.”<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>In yet more places, it is assigned to lbn and vice versa.<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>These multiple uses for the same structure member are
confusing me as to the actual use in particular places. Any help would be
appreciated.<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>Sincerely,<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>David Maung<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
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