On Thu, 4 Oct 2012, Jan Beulich wrote:
> Commit 20167d3421a089a1bf1bd680b150dc69c9506810 ("x86-64: Fix
> accounting in kernel_physical_mapping_init()") went a little too far
> by entirely removing the counting of pre-populated page tables: This
> should be done at boot time (to cover the page tables set up in early
> boot code), but shouldn't be done during memory hot add.
>
> Hence, re-add the removed increments of "pages", but make them and the
> one in phys_pte_init() conditional upon !after_bootmem.
>
> Reported-by: Hugh Dickins <hu...@google.com>
> Signed-off-by: Jan Beulich <jbeul...@suse.com>
I think this has not yet been picked up: perhaps it's awaiting an
Acked-by: Hugh Dickins <hu...@google.com>
or a
Tested-by: Hugh Dickins <hu...@google.com>
but I hesitated to give those because you understand what's going
on here much better than I pretend to.
>
> ---
> Not sure if this ought to be copied to stable@.
I guess not. Much as I like my kernels to show good meminfo numbers,
I was recently saying that David Rientjes's patches to get Unevictable
and Mlocked right were not important enough for stable, and I think
those numbers are more interesting to most people than the DirectMaps.
But I'd be happily overruled on all three patches.
Hugh
>
> ---
> arch/x86/mm/init_64.c | 7 ++++++-
> 1 file changed, 6 insertions(+), 1 deletion(-)
>
> --- 3.6/arch/x86/mm/init_64.c
> +++ 3.6-x86_64-page-table-count/arch/x86/mm/init_64.c
> @@ -386,7 +386,8 @@ phys_pte_init(pte_t *pte_page, unsigned
> * these mappings are more intelligent.
> */
> if (pte_val(*pte)) {
> - pages++;
> + if (!after_bootmem)
> + pages++;
> continue;
> }
>
> @@ -451,6 +452,8 @@ phys_pmd_init(pmd_t *pmd_page, unsigned
> * attributes.
> */
> if (page_size_mask & (1 << PG_LEVEL_2M)) {
> + if (!after_bootmem)
> + pages++;
> last_map_addr = next;
> continue;
> }
> @@ -526,6 +529,8 @@ phys_pud_init(pud_t *pud_page, unsigned
> * attributes.
> */
> if (page_size_mask & (1 << PG_LEVEL_1G)) {
> + if (!after_bootmem)
> + pages++;
> last_map_addr = next;
> continue;
> }
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majord...@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
