Messages in this thread | | | Date | Wed, 27 May 2009 13:02:46 +0900 | From | Daisuke Nishimura <> | Subject | Re: [RFC][PATCH 2/5] add SWAP_HAS_CACHE flag to swap_map |
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> @@ -1067,21 +1113,21 @@ static int try_to_unuse(unsigned int typ > } > > /* > - * How could swap count reach 0x7fff when the maximum > - * pid is 0x7fff, and there's no way to repeat a swap > - * page within an mm (except in shmem, where it's the > - * shared object which takes the reference count)? > - * We believe SWAP_MAP_MAX cannot occur in Linux 2.4. > - * > + * How could swap count reach 0x7ffe ? > + * There's no way to repeat a swap page within an mm > + * (except in shmem, where it's the shared object which takes > + * the reference count)? > + * We believe SWAP_MAP_MAX cannot occur.(if occur, unsigned > + * short is too small....) > * If that's wrong, then we should worry more about > * exit_mmap() and do_munmap() cases described above: > * we might be resetting SWAP_MAP_MAX too early here. > * We know "Undead"s can happen, they're okay, so don't > * report them; but do report if we reset SWAP_MAP_MAX. > */ > - if (*swap_map == SWAP_MAP_MAX) { > + if (swap_count(*swap_map) == SWAP_MAP_MAX) { > spin_lock(&swap_lock); > - *swap_map = 1; > + *swap_map = make_swap_count(0, 1); Can we assume the entry has SWAP_HAS_CACHE here ? Shouldn't we check PageSwapCache beforehand ?
> spin_unlock(&swap_lock); > reset_overflow = 1; > }
Thanks, Daisuke Nishimura.
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