lkl: irq: atomically drain pending IRQs#640
Merged
Merged
Conversation
Pending IRQs can be published from host threads while the LKL CPU is owned elsewhere or while interrupts are disabled. Avoid checking the IRQ pending bitmaps with plain loads before the atomic fetch-and-clear, as that can race with concurrent updates and skip newly published work. Also keep draining the index bitmap until it becomes empty, so IRQs queued while earlier pending IRQs are being handled are delivered in the same pass instead of waiting for a later run_irqs() invocation. Signed-off-by: clingfei <chenglingfei@foxmail.com>
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
2 participants
Add this suggestion to a batch that can be applied as a single commit.This suggestion is invalid because no changes were made to the code.Suggestions cannot be applied while the pull request is closed.Suggestions cannot be applied while viewing a subset of changes.Only one suggestion per line can be applied in a batch.Add this suggestion to a batch that can be applied as a single commit.Applying suggestions on deleted lines is not supported.You must change the existing code in this line in order to create a valid suggestion.Outdated suggestions cannot be applied.This suggestion has been applied or marked resolved.Suggestions cannot be applied from pending reviews.Suggestions cannot be applied on multi-line comments.Suggestions cannot be applied while the pull request is queued to merge.Suggestion cannot be applied right now. Please check back later.
Pending IRQs can be published from host threads while the LKL CPU is owned elsewhere or while interrupts are disabled. Avoid checking the IRQ pending bitmaps with plain loads before the atomic fetch-and-clear, as that can race with concurrent updates and skip newly published work.
Also keep draining the index bitmap until it becomes empty, so IRQs queued while earlier pending IRQs are being handled are delivered in the same pass instead of waiting for a later run_irqs() invocation.