Merge tag 'trace-ring-buffer-v6.13' of...
Merge tag 'trace-ring-buffer-v6.13' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace Pull trace ring-buffer updates from Steven Rostedt: - Limit time interrupts are disabled in rb_check_pages() rb_check_pages() is called after the ring buffer size is updated to make sure that the ring buffer has not been corrupted. Commit c2274b90 ("ring-buffer: Fix a race between readers and resize checks") fixed a race with the check pages and simultaneous resizes to the ring buffer by adding a raw_spin_lock_irqsave() around the check operation. Although this was a simple fix, it would hold interrupts disabled for non determinative amount of time. This could harm PREEMPT_RT operations. Instead, modify the logic by adding a counter when the buffer is modified and to release the raw_spin_lock() at each iteration. It checks the counter under the lock to see if a modification happened during the loop, and if it did, it would restart the loop up to 3 times. After 3 times, it will simply exit the check, as it is unlikely that would ever happen as buffer resizes are rare occurrences. - Replace some open coded str_low_high() with the helper - Fix some documentation/comments * tag 'trace-ring-buffer-v6.13' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: ring-buffer: Correct a grammatical error in a comment ring-buffer: Use str_low_high() helper in ring_buffer_producer() ring-buffer: Reorganize kerneldoc parameter names ring-buffer: Limit time with disabled interrupts in rb_check_pages()
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