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author | Andrei Vagin <avagin@google.com> | 2023-11-07 01:09:58 +0300 |
---|---|---|
committer | Andrew Morton <akpm@linux-foundation.org> | 2023-12-11 03:51:35 +0300 |
commit | e6a9a2cbc13bf43e4c03f57666e93d511249d5d7 (patch) | |
tree | cd5fec80885e60859f3ec6faeb490b34211cabb8 /include/uapi/linux/fs.h | |
parent | 8ff252663d30f5c0bcb0bb336c1a5ed7c37d9730 (diff) | |
download | linux-e6a9a2cbc13bf43e4c03f57666e93d511249d5d7.tar.xz |
fs/proc/task_mmu: report SOFT_DIRTY bits through the PAGEMAP_SCAN ioctl
The PAGEMAP_SCAN ioctl returns information regarding page table entries.
It is more efficient compared to reading pagemap files. CRIU can start to
utilize this ioctl, but it needs info about soft-dirty bits to track
memory changes.
We are aware of a new method for tracking memory changes implemented in
the PAGEMAP_SCAN ioctl. For CRIU, the primary advantage of this method is
its usability by unprivileged users. However, it is not feasible to
transparently replace the soft-dirty tracker with the new one. The main
problem here is userfault descriptors that have to be preserved between
pre-dump iterations. It means criu continues supporting the soft-dirty
method to avoid breakage for current users. The new method will be
implemented as a separate feature.
[avagin@google.com: update tools/include/uapi/linux/fs.h]
Link: https://lkml.kernel.org/r/20231107164139.576046-1-avagin@google.com
Link: https://lkml.kernel.org/r/20231106220959.296568-1-avagin@google.com
Signed-off-by: Andrei Vagin <avagin@google.com>
Reviewed-by: Muhammad Usama Anjum <usama.anjum@collabora.com>
Cc: Michał Mirosław <mirq-linux@rere.qmqm.pl>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Diffstat (limited to 'include/uapi/linux/fs.h')
-rw-r--r-- | include/uapi/linux/fs.h | 1 |
1 files changed, 1 insertions, 0 deletions
diff --git a/include/uapi/linux/fs.h b/include/uapi/linux/fs.h index da43810b7485..48ad69f7722e 100644 --- a/include/uapi/linux/fs.h +++ b/include/uapi/linux/fs.h @@ -316,6 +316,7 @@ typedef int __bitwise __kernel_rwf_t; #define PAGE_IS_SWAPPED (1 << 4) #define PAGE_IS_PFNZERO (1 << 5) #define PAGE_IS_HUGE (1 << 6) +#define PAGE_IS_SOFT_DIRTY (1 << 7) /* * struct page_region - Page region with flags |