Question about free_pgd_slow ?

[bill_carson@126.com (rocky)]

At 2011-03-07 22:44:58?"Rabin Vincent" <rabin@rab.in> wrote: >2011/3/5 rocky <bill_carson@126.com>: >pgd_free() on the other hand is safe because it's called when we've >switched away from this mm, and the page table is no longer in use >(mm->mm_count == 0). > >Have a look at exit_mm(), which increases the mm_count before calling >mm_put(), and finish_task_switch(), which does the mmdrop().

crystal clear:)
your explanation DOES make sense

I can say when mm->mm_count ==0 , current_thread_info is not the thread info corresponding with mm used in mmdrop()

currently I am working on hugetlb for ARM
I put huge page table in thread_info when calling pgd_alloc
and wants to free it in pgd_free which is doomed to fail.
now I move those cookies into mm_struct , definitely not right place.
but I cannot find a desired place!

Thanks Rabin

rocky













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