On 10/27/25 10:32 PM, Chaitanya Kulkarni wrote:
> Add informational messages during blktrace setup when version 1 tools
> are used on kernels with CONFIG_BLK_DEV_ZONED enabled. This alerts users
> that REQ_OP_ZONE_* events will be dropped and suggests upgrading to
> blktrace tools version 2 or later.
>
> The warning is printed once during trace setup to inform users about
> the limitation without spamming the logs during tracing operations.
> Version 2 blktrace tools properly handle zone management operations
> (zone reset, zone open, zone close, zone finish, zone append) that
> were added for zoned block devices.
>
> Example output:
> blktests (master) # ./check blktrace
> blktrace/001 (blktrace zone management command tracing) [passed]
> runtime 3.882s ... 3.866s
> blktests (master) # dmesg -c
> [ 95.874361] blktrace: nullb0:blktrace events for REQ_OP_ZONE_XXX will be
> dropped
> [ 95.874372] blktrace: use blktrace tools version >= 2 to track
> REQ_OP_ZONE_XXX
> blktests (master) #
>
> This helps users understand why zone operation traces may be missing
> when using older blktrace tool versions with modern kernels that
> support REQ_OP_ZONE_XXX in blktrace.
>
> Signed-off-by: Chaitanya Kulkarni <[email protected]>
> ---
> kernel/trace/blktrace.c | 6 ++++++
> 1 file changed, 6 insertions(+)
>
> diff --git a/kernel/trace/blktrace.c b/kernel/trace/blktrace.c
> index 776ae4190f36..200d0deb6c90 100644
> --- a/kernel/trace/blktrace.c
> +++ b/kernel/trace/blktrace.c
> @@ -690,6 +690,12 @@ static void blk_trace_setup_finalize(struct
> request_queue *q,
> */
> strreplace(buts->name, '/', '_');
>
> + if (version == 1 && (IS_ENABLED(CONFIG_BLK_DEV_ZONED))) {
Redundant parens around IS_ENABLED() here.
> + pr_info("%s:blktrace events for REQ_OP_ZONE_XXX will be
> dropped\n",
> + name);
%s: blktrace events [...]? Seems weird not to have a space there.
--
Jens Axboe
