[PATCH v2 00/15] block: add blktrace support for zoned block device commands

Johannes Thumshirn
2025-09-25T15:02:43Z

This patch series extends the kernel blktrace infrastructure to support
tracing zoned block device commands. Zoned block devices (e.g., ZAC/ZBC and
ZNS) introduce command types such as zone open, close, reset, finish, and
zone append. These are currently not visible in blktrace, making it difficult
to debug and analyze I/O workloads on zoned devices.

The patches in this series utilize the new trace points for these zone
management operations, and propagate the necessary context to the blktrace
logging path. These additions are designed to be backward-compatible, and are
only active when zoned devices are in use.

In order to not break the user-space ABI, a new ioctl was introduced to request
the new version of the blk_io_trace with extended 'action' field.

The user-space tools in the blktrace suite are updated in a separate patch
series to interpret and display the new trace events.This patch series extends the kernel blktrace infrastructure to support
tracing zoned block device commands. Zoned block devices (e.g., ZAC/ZBC and
ZNS) introduce command types such as zone open, close, reset, finish, and
zone append. These are currently not visible in blktrace, making it difficult
to debug and analyze I/O workloads on zoned devices.

The patches in this series utilize the new trace points for these zone
management operations, and propagate the necessary context to the blktrace
logging path. These additions are designed to be backward-compatible, and are
only active when zoned devices are in use.

In order to not break the user-space ABI, a new ioctl was introduced to request
the new version of the blk_io_trace with extended 'action' field.

The user-space tools in the blktrace suite are updated in a separate patch
series to interpret and display the new trace events.

Changes to v1:
- Incroporate feedback from Christoph

Johannes Thumshirn (15):
blktrace: only calculate trace length once
blktrace: factor out recording a blktrace event
blktrace: split out relaying a blktrace event
blktrace: untangle if/else sequence in __blk_add_trace
blktrace: change the internal action to 64bit
blktrace: split do_blk_trace_setup into two functions
blktrace: add definitions for blk_user_trace_setup2
blktrace: pass blk_user_trace2 to setup functions
blktrace: add definitions for struct blk_io_trace2
blktrace: differentiate between blk_io_trace versions
blktrace: add block trace commands for zone operations
blktrace: expose ZONE APPEND completions to blktrace
blktrace: trace zone management operations
blktrace: trace zone write plugging operations
blktrace: handle BLKTRACESETUP2 ioctl

block/ioctl.c | 1 +
include/linux/blktrace_api.h | 3 +-
include/uapi/linux/blktrace_api.h | 54 +++-
include/uapi/linux/fs.h | 1 +
kernel/trace/blktrace.c | 458 +++++++++++++++++++++++-------
5 files changed, 407 insertions(+), 110 deletions(-)

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2.51.0