[PATCH v1 0/2] hrtimer: Add hrtimer_forward_safe_from_callback()

[FUJITA Tomonori <tomo@flapping.org>]

From: FUJITA Tomonori <fujita.tomonori@gmail.com>

Safe Rust code can arm a timer while its callback is running, so the
Rust abstraction cannot offer hrtimer_forward() from the callback as a
safe API.

Thomas suggested a helper that does the check and the update with the
base lock held [1]. Patch 1 adds it. Patch 2 makes the Rust callback
context use it.

The helper is not Rust specific. As Thomas noted, it can be used for
i915_pmu too. null_blk can use it as well. I can send those
conversions after the helper is merged.

[1] https://lore.kernel.org/all/877bk3ixp5.ffs@fw13/


FUJITA Tomonori (2):
  hrtimer: Add hrtimer_forward_safe_from_callback()
  rust: hrtimer: Use hrtimer_forward_safe_from_callback()

 include/linux/hrtimer.h     |  4 ++++
 kernel/time/hrtimer.c       | 30 ++++++++++++++++++++++++++++++
 rust/kernel/time/hrtimer.rs | 25 ++++++++++++++++++-------
 3 files changed, 52 insertions(+), 7 deletions(-)


base-commit: 6628e7d4c6b25c8d18f1345e3a20d21829aae7e4
-- 
2.43.0