On Fri, 6 Dec 2002, Martin Maletinsky wrote: > After getting the corresponding page table entry, the function makes a > check, which I don't quite understand - if write access is requested to > the page, it not only checks the write permission in the page table > entry (with pte_write()), but also the dirty bit (with pte_dirty()). Why > does a page need to be dirty in the case write == 1 (see line 444 in the > code excerpt below? If write == 1, then somebody wants to write to the page NOW. In that case it's more efficient to just set the dirty bit than to take a trap later on; remember that many CPUs can't keep track of the dirty bit in hardware but trap to the OS. Rik -- A: No. Q: Should I include quotations after my reply? http://www.surriel.com/ http://guru.conectiva.com/ -- Kernelnewbies: Help each other learn about the Linux kernel. Archive: http://mail.nl.linux.org/kernelnewbies/ FAQ: http://kernelnewbies.org/faq/
