Soft dirty bit allows us to track which pages are written since the last clear_ref (by "echo 4 > /proc/pid/clear_refs".) This is useful for userspace applications to know their memory footprints. Note that the kernel exposes this flag via bit[55] of /proc/pid/pagemap, and the semantics is not a default one (scheduled to be the default in the near future.) However, it shifts to the new semantics at the first clear_ref, and the users of soft dirty bit always do it before utilizing the bit, so that's not a big deal. Users must avoid relying on the bit in page-types before the first clear_ref. Signed-off-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> Cc: Wu Fengguang <fengguang.wu@intel.com> Cc: Pavel Emelyanov <xemul@parallels.com> Cc: Cyrill Gorcunov <gorcunov@openvz.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
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| acpi | ||
| asm-generic | ||
| clocksource | ||
| crypto | ||
| drm | ||
| dt-bindings | ||
| keys | ||
| kvm | ||
| linux | ||
| math-emu | ||
| media | ||
| memory | ||
| misc | ||
| net | ||
| pcmcia | ||
| ras | ||
| rdma | ||
| rxrpc | ||
| scsi | ||
| sound | ||
| target | ||
| trace | ||
| uapi | ||
| video | ||
| xen | ||
| Kbuild | ||