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| author | Carlos Llamas <[email protected]> | 2024-12-10 14:30:58 +0000 |
|---|---|---|
| committer | Greg Kroah-Hartman <[email protected]> | 2024-12-24 08:35:23 +0000 |
| commit | d1716b4b78fb392a5514c8863e8ba287cc4580c2 (patch) | |
| tree | 55fc9b15ad67c348338cab830a0455d28d53d94f /drivers/android/binder_alloc.h | |
| parent | Revert "binder: switch alloc->mutex to spinlock_t" (diff) | |
| download | kernel-d1716b4b78fb392a5514c8863e8ba287cc4580c2.tar.gz kernel-d1716b4b78fb392a5514c8863e8ba287cc4580c2.zip | |
binder: concurrent page installation
Allow multiple callers to install pages simultaneously by switching the
mmap_sem from write-mode to read-mode. Races to the same PTE are handled
using get_user_pages_remote() to retrieve the already installed page.
This method significantly reduces contention in the mmap semaphore.
To ensure safety, vma_lookup() is used (instead of alloc->vma) to avoid
operating on an isolated VMA. In addition, zap_page_range_single() is
called under the alloc->mutex to avoid racing with the shrinker.
Many thanks to Barry Song who posted a similar approach [1].
Link: https://lore.kernel.org/all/[email protected]/ [1]
Cc: David Hildenbrand <[email protected]>
Cc: Barry Song <[email protected]>
Cc: Suren Baghdasaryan <[email protected]>
Cc: Liam R. Howlett <[email protected]>
Reviewed-by: Suren Baghdasaryan <[email protected]>
Signed-off-by: Carlos Llamas <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>
Diffstat (limited to 'drivers/android/binder_alloc.h')
0 files changed, 0 insertions, 0 deletions