[PATCH v2 3/3] bcache: Remove unnecessary select MIN_HEAP
From: Kuan-Wei Chiu
Date: Sat Jun 14 2025 - 16:25:00 EST
After reverting the transition to the generic min heap library, bcache
no longer depends on MIN_HEAP. The select entry can be removed to
reduce code size and shrink the kernel's attack surface.
This change effectively reverts the bcache-related part of commit
92a8b224b833 ("lib/min_heap: introduce non-inline versions of min heap
API functions").
This is part of a series of changes to address a performance
regression caused by the use of the generic min_heap implementation.
As reported by Robert, bcache now suffers from latency spikes, with
P100 (max) latency increasing from 600 ms to 2.4 seconds every 5
minutes. These regressions degrade bcache's effectiveness as a
low-latency cache layer and lead to frequent timeouts and application
stalls in production environments.
Link: https://lore.kernel.org/lkml/CAJhEC05+0S69z+3+FB2Cd0hD+pCRyWTKLEOsc8BOmH73p1m+KQ@xxxxxxxxxxxxxx
Fixes: 866898efbb25 ("bcache: remove heap-related macros and switch to generic min_heap")
Fixes: 92a8b224b833 ("lib/min_heap: introduce non-inline versions of min heap API functions")
Reported-by: Robert Pang <robertpang@xxxxxxxxxx>
Closes: https://lore.kernel.org/linux-bcache/CAJhEC06F_AtrPgw2-7CvCqZgeStgCtitbD-ryuPpXQA-JG5XXw@xxxxxxxxxxxxxx
Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Kuan-Wei Chiu <visitorckw@xxxxxxxxx>
---
drivers/md/bcache/Kconfig | 1 -
1 file changed, 1 deletion(-)
diff --git a/drivers/md/bcache/Kconfig b/drivers/md/bcache/Kconfig
index d4697e79d5a3..b2d10063d35f 100644
--- a/drivers/md/bcache/Kconfig
+++ b/drivers/md/bcache/Kconfig
@@ -5,7 +5,6 @@ config BCACHE
select BLOCK_HOLDER_DEPRECATED if SYSFS
select CRC64
select CLOSURES
- select MIN_HEAP
help
Allows a block device to be used as cache for other devices; uses
a btree for indexing and the layout is optimized for SSDs.
--
2.34.1