Files
linux/include/trace/events
Leo Martins cc970d21c4 btrfs: add tracepoint for search slot restart tracking
Add a btrfs_search_slot_restart tracepoint that fires at each restart
site in btrfs_search_slot(), recording the root, tree level, and
reason for the restart. This enables tracking search slot restarts
which contribute to COW amplification under memory pressure.

The four restart reasons are:
 - write_lock: insufficient write lock level, need to restart with
   higher lock
 - setup_nodes: node setup returned -EAGAIN
 - slot_zero: insertion at slot 0 requires higher write lock level
 - read_block: read_block_for_search returned -EAGAIN (block not
   cached or lock contention)

COW counts are already tracked by the existing trace_btrfs_cow_block()
tracepoint. The per-restart-site tracepoint avoids counter overhead
in the critical path when tracepoints are disabled, and provides
richer per-event information that bpftrace scripts can aggregate into
counts, histograms, and per-root breakdowns.

Reviewed-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: Boris Burkov <boris@bur.io>
Signed-off-by: Leo Martins <loemra.dev@gmail.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2026-04-07 18:56:00 +02:00
..
2024-11-22 11:43:27 -07:00
2025-08-26 17:34:31 -07:00
2026-01-29 16:00:57 +01:00
2024-05-08 10:39:26 +01:00
2023-12-29 11:58:27 -08:00
2023-07-17 08:18:17 -06:00
2024-11-11 00:26:46 -08:00
2025-07-09 22:41:55 -07:00
2024-05-14 07:22:35 -06:00
2024-09-11 20:44:31 -07:00
2025-09-13 16:55:07 -07:00
2025-11-14 17:05:53 +01:00
2024-09-28 15:13:56 +02:00
2025-09-21 14:22:28 -07:00
2025-11-04 08:32:14 +01:00
2024-06-19 12:44:22 +01:00
2025-04-11 18:58:10 -07:00
2025-10-27 11:10:50 +00:00
2025-07-14 12:46:48 -04:00
2023-07-17 08:18:17 -06:00
2023-09-19 07:04:49 +02:00