Hi Steve, Add support for displaying bitmasks in human-readable list format (e.g., 0,2-5,7) in addition to the default hexadecimal bitmap representation. This is particularly useful when tracing CPU masks and other large bitmasks where individual bit positions are more meaningful than their hexadecimal encoding.
When the "bitmask-list" option is enabled, the printk "%*pbl" format specifier is used to render bitmasks as comma-separated ranges, making trace output easier to interpret for complex CPU configurations and large bitmask values. This iteration incorporates the use of iter->tmp_seq to ensure the implementation is robust, instance-aware, and free from buffer contention or duplication issues. Please let me know your thoughts. Changes since v1 [1]: - Introduce new helper trace_seq_bitmask_list() (Steven Rostedt) - Use iter->tmp_seq as a scratchpad to prevent buffer collisions and duplication - Update trace_print_bitmask_seq() signature to accept trace_iterator instead of trace_seq - Add declaration for trace_seq_bitmask_list() and provide necessary stub definitions - Update __get_bitmask and __get_rel_bitmask macros to pass iter to the bitmask helper - Implement instance-aware bitmask formatting using iter->tmp_seq as a scratchpad to prevent buffer collisions and duplication [1]: https://lore.kernel.org/lkml/[email protected]/ Aaron Tomlin (1): tracing: Add bitmask-list option for human-readable bitmask display Documentation/trace/ftrace.rst | 9 +++++++ include/linux/trace_events.h | 8 +++--- include/linux/trace_seq.h | 12 ++++++++- include/trace/stages/stage3_trace_output.h | 4 +-- kernel/trace/trace.h | 1 + kernel/trace/trace_output.c | 30 +++++++++++++++++++--- kernel/trace/trace_seq.c | 29 ++++++++++++++++++++- 7 files changed, 82 insertions(+), 11 deletions(-) -- 2.51.0
