On 4/17/26 12:28 PM, Bart Van Assche wrote: > On 3/19/26 3:19 PM, Aaron Tomlin wrote: >> To guarantee zero performance overhead for production kernels compiled >> without debugfs, the underlying atomic_t variables and their associated >> increment routines are strictly guarded behind CONFIG_BLK_DEBUG_FS. >> When this configuration is disabled, the tracking logic compiles down >> to a safe no-op. > > I don't think that's sufficient. Please use per-cpu counters to > minimize the overhead for kernels in which debugfs is enabled.
Agree, this is the usual nonsense of thinking you can hide any overhead behind a config option, when in practice production kernels very much DO have CONFIG_DEBUGFS enabled. -- Jens Axboe
