The patch titled
Subject: Revert "bcache: update min_heap_callbacks to use default builtin swap"
has been added to the -mm mm-hotfixes-unstable branch. Its filename is
revert-bcache-update-min_heap_callbacks-to-use-default-builtin-swap.patch
This patch will shortly appear at
https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patche…
This patch will later appear in the mm-hotfixes-unstable branch at
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
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a) Consider who else should be cc'ed
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c) Ideally: find the original patch on the mailing list and do a
reply-to-all to that, adding suitable additional cc's
*** Remember to use Documentation/process/submit-checklist.rst when testing your code ***
The -mm tree is included into linux-next via the mm-everything
branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
and is updated there every 2-3 working days
------------------------------------------------------
From: Kuan-Wei Chiu <visitorckw(a)gmail.com>
Subject: Revert "bcache: update min_heap_callbacks to use default builtin swap"
Date: Sun, 15 Jun 2025 04:23:51 +0800
Patch series "bcache: Revert min_heap migration due to performance
regression".
This patch series reverts the migration of bcache from its original heap
implementation to the generic min_heap library. While the original change
aimed to simplify the code and improve maintainability, it introduced a
severe performance regression in real-world scenarios.
As reported by Robert, systems using bcache now suffer from periodic
latency spikes, with P100 (max) latency increasing from 600 ms to 2.4
seconds every 5 minutes. This degrades bcache's value as a low-latency
caching layer, and leads to frequent timeouts and application stalls in
production environments.
The primary cause of this regression is the behavior of the generic
min_heap implementation's bottom-up sift_down, which performs up to 2 *
log2(n) comparisons when many elements are equal. The original top-down
variant used by bcache only required O(1) comparisons in such cases. The
issue was further exacerbated by commit 92a8b224b833 ("lib/min_heap:
introduce non-inline versions of min heap API functions"), which
introduced non-inlined versions of the min_heap API, adding function call
overhead to a performance-critical hot path.
This patch (of 3):
This reverts commit 3d8a9a1c35227c3f1b0bd132c9f0a80dbda07b65.
Although removing the custom swap function simplified the code, this
change is part of a broader migration to the generic min_heap API that
introduced significant performance regressions in bcache.
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.
This revert is part of a series of changes to restore previous performance
by undoing the min_heap transition.
Link: https://lkml.kernel.org/r/20250614202353.1632957-1-visitorckw@gmail.com
Link: https://lore.kernel.org/lkml/CAJhEC05+0S69z+3+FB2Cd0hD+pCRyWTKLEOsc8BOmH73p…
Link: https://lkml.kernel.org/r/20250614202353.1632957-2-visitorckw@gmail.com
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")
Signed-off-by: Kuan-Wei Chiu <visitorckw(a)gmail.com>
Reported-by: Robert Pang <robertpang(a)google.com>
Closes: https://lore.kernel.org/linux-bcache/CAJhEC06F_AtrPgw2-7CvCqZgeStgCtitbD-ry…
Acked-by: Coly Li <colyli(a)kernel.org>
Cc: Ching-Chun (Jim) Huang <jserv(a)ccns.ncku.edu.tw>
Cc: Kent Overstreet <kent.overstreet(a)linux.dev>
Cc: <stable(a)vger.kernel.org>
Signed-off-by: Andrew Morton <akpm(a)linux-foundation.org>
---
drivers/md/bcache/alloc.c | 11 +++++++++--
drivers/md/bcache/bset.c | 14 +++++++++++---
drivers/md/bcache/extents.c | 10 +++++++++-
drivers/md/bcache/movinggc.c | 10 +++++++++-
4 files changed, 38 insertions(+), 7 deletions(-)
--- a/drivers/md/bcache/alloc.c~revert-bcache-update-min_heap_callbacks-to-use-default-builtin-swap
+++ a/drivers/md/bcache/alloc.c
@@ -189,16 +189,23 @@ static inline bool new_bucket_min_cmp(co
return new_bucket_prio(ca, *lhs) < new_bucket_prio(ca, *rhs);
}
+static inline void new_bucket_swap(void *l, void *r, void __always_unused *args)
+{
+ struct bucket **lhs = l, **rhs = r;
+
+ swap(*lhs, *rhs);
+}
+
static void invalidate_buckets_lru(struct cache *ca)
{
struct bucket *b;
const struct min_heap_callbacks bucket_max_cmp_callback = {
.less = new_bucket_max_cmp,
- .swp = NULL,
+ .swp = new_bucket_swap,
};
const struct min_heap_callbacks bucket_min_cmp_callback = {
.less = new_bucket_min_cmp,
- .swp = NULL,
+ .swp = new_bucket_swap,
};
ca->heap.nr = 0;
--- a/drivers/md/bcache/bset.c~revert-bcache-update-min_heap_callbacks-to-use-default-builtin-swap
+++ a/drivers/md/bcache/bset.c
@@ -1093,6 +1093,14 @@ static inline bool new_btree_iter_cmp(co
return bkey_cmp(_l->k, _r->k) <= 0;
}
+static inline void new_btree_iter_swap(void *iter1, void *iter2, void __always_unused *args)
+{
+ struct btree_iter_set *_iter1 = iter1;
+ struct btree_iter_set *_iter2 = iter2;
+
+ swap(*_iter1, *_iter2);
+}
+
static inline bool btree_iter_end(struct btree_iter *iter)
{
return !iter->heap.nr;
@@ -1103,7 +1111,7 @@ void bch_btree_iter_push(struct btree_it
{
const struct min_heap_callbacks callbacks = {
.less = new_btree_iter_cmp,
- .swp = NULL,
+ .swp = new_btree_iter_swap,
};
if (k != end)
@@ -1149,7 +1157,7 @@ static inline struct bkey *__bch_btree_i
struct bkey *ret = NULL;
const struct min_heap_callbacks callbacks = {
.less = cmp,
- .swp = NULL,
+ .swp = new_btree_iter_swap,
};
if (!btree_iter_end(iter)) {
@@ -1223,7 +1231,7 @@ static void btree_mergesort(struct btree
: bch_ptr_invalid;
const struct min_heap_callbacks callbacks = {
.less = b->ops->sort_cmp,
- .swp = NULL,
+ .swp = new_btree_iter_swap,
};
/* Heapify the iterator, using our comparison function */
--- a/drivers/md/bcache/extents.c~revert-bcache-update-min_heap_callbacks-to-use-default-builtin-swap
+++ a/drivers/md/bcache/extents.c
@@ -266,12 +266,20 @@ static bool new_bch_extent_sort_cmp(cons
return !(c ? c > 0 : _l->k < _r->k);
}
+static inline void new_btree_iter_swap(void *iter1, void *iter2, void __always_unused *args)
+{
+ struct btree_iter_set *_iter1 = iter1;
+ struct btree_iter_set *_iter2 = iter2;
+
+ swap(*_iter1, *_iter2);
+}
+
static struct bkey *bch_extent_sort_fixup(struct btree_iter *iter,
struct bkey *tmp)
{
const struct min_heap_callbacks callbacks = {
.less = new_bch_extent_sort_cmp,
- .swp = NULL,
+ .swp = new_btree_iter_swap,
};
while (iter->heap.nr > 1) {
struct btree_iter_set *top = iter->heap.data, *i = top + 1;
--- a/drivers/md/bcache/movinggc.c~revert-bcache-update-min_heap_callbacks-to-use-default-builtin-swap
+++ a/drivers/md/bcache/movinggc.c
@@ -190,6 +190,14 @@ static bool new_bucket_cmp(const void *l
return GC_SECTORS_USED(*_l) >= GC_SECTORS_USED(*_r);
}
+static void new_bucket_swap(void *l, void *r, void __always_unused *args)
+{
+ struct bucket **_l = l;
+ struct bucket **_r = r;
+
+ swap(*_l, *_r);
+}
+
static unsigned int bucket_heap_top(struct cache *ca)
{
struct bucket *b;
@@ -204,7 +212,7 @@ void bch_moving_gc(struct cache_set *c)
unsigned long sectors_to_move, reserve_sectors;
const struct min_heap_callbacks callbacks = {
.less = new_bucket_cmp,
- .swp = NULL,
+ .swp = new_bucket_swap,
};
if (!c->copy_gc_enabled)
_
Patches currently in -mm which might be from visitorckw(a)gmail.com are
revert-bcache-update-min_heap_callbacks-to-use-default-builtin-swap.patch
revert-bcache-remove-heap-related-macros-and-switch-to-generic-min_heap.patch
bcache-remove-unnecessary-select-min_heap.patch
lib-math-gcd-use-static-key-to-select-implementation-at-runtime.patch
riscv-optimize-gcd-code-size-when-config_riscv_isa_zbb-is-disabled.patch
riscv-optimize-gcd-performance-on-risc-v-without-zbb-extension.patch
Some libc's like musl libc don't provide execinfo.h since it's not part
of POSIX. In order to fix compilation on musl, only include execinfo.h
if available (HAVE_BACKTRACE_SUPPORT)
This was discovered with c104c16073b7 ("Kunit to check the longest symbol length")
which starts to include linux/kallsyms.h with Alpine Linux' configs.
Signed-off-by: Achill Gilgenast <fossdd(a)pwned.life>
Cc: stable(a)vger.kernel.org
---
tools/include/linux/kallsyms.h | 4 ++++
1 file changed, 4 insertions(+)
diff --git a/tools/include/linux/kallsyms.h b/tools/include/linux/kallsyms.h
index 5a37ccbec54f..f61a01dd7eb7 100644
--- a/tools/include/linux/kallsyms.h
+++ b/tools/include/linux/kallsyms.h
@@ -18,6 +18,7 @@ static inline const char *kallsyms_lookup(unsigned long addr,
return NULL;
}
+#ifdef HAVE_BACKTRACE_SUPPORT
#include <execinfo.h>
#include <stdlib.h>
static inline void print_ip_sym(const char *loglvl, unsigned long ip)
@@ -30,5 +31,8 @@ static inline void print_ip_sym(const char *loglvl, unsigned long ip)
free(name);
}
+#else
+static inline void print_ip_sym(const char *loglvl, unsigned long ip) {}
+#endif
#endif
--
2.50.0.rc2
commit: 10685681bafc ("net_sched: sch_sfq: don't allow 1 packet limit")
fixes CVE-2024-57996 and commit: b3bf8f63e617 ("net_sched: sch_sfq: move
the limit validation") fixes CVE-2025-37752.
Patches 3 and 5 are CVE fixes for above mentioned CVEs. Patch 1,2 and 4
are pulled in as stable-deps.
Testing performed on the patched 5.10.238 kernel with the above 5
patches: (Used latest upstream kselftests for tc-testing)
# uname -a
Linux hamogala-vm-6 5.10.238+ #2 SMP Sun Jun 15 17:27:54 GMT 2025 x86_64 x86_64 x86_64 GNU/Linux
# ./tdc.py -f tc-tests/qdiscs/sfq.json
-- ns/SubPlugin.__init__
Test 7482: Create SFQ with default setting
Test c186: Create SFQ with limit setting
Test ae23: Create SFQ with perturb setting
Test a430: Create SFQ with quantum setting
Test 4539: Create SFQ with divisor setting
Test b089: Create SFQ with flows setting
Test 99a0: Create SFQ with depth setting
Test 7389: Create SFQ with headdrop setting
Test 6472: Create SFQ with redflowlimit setting
Test 8929: Show SFQ class
Test 4d6f: Check that limit of 1 is rejected
Test 7f8f: Check that a derived limit of 1 is rejected (limit 2 depth 1 flows 1)
Test 5168: Check that a derived limit of 1 is rejected (limit 2 depth 1 divisor 1)
All test results:
1..13
ok 1 7482 - Create SFQ with default setting
ok 2 c186 - Create SFQ with limit setting
ok 3 ae23 - Create SFQ with perturb setting
ok 4 a430 - Create SFQ with quantum setting
ok 5 4539 - Create SFQ with divisor setting
ok 6 b089 - Create SFQ with flows setting
ok 7 99a0 - Create SFQ with depth setting
ok 8 7389 - Create SFQ with headdrop setting
ok 9 6472 - Create SFQ with redflowlimit setting
ok 10 8929 - Show SFQ class
ok 11 4d6f - Check that limit of 1 is rejected
ok 12 7f8f - Check that a derived limit of 1 is rejected (limit 2 depth 1 flows 1)
ok 13 5168 - Check that a derived limit of 1 is rejected (limit 2 depth 1 divisor 1)
Thanks,
Harshit
Eric Dumazet (2):
net_sched: sch_sfq: annotate data-races around q->perturb_period
net_sched: sch_sfq: handle bigger packets
Octavian Purdila (3):
net_sched: sch_sfq: don't allow 1 packet limit
net_sched: sch_sfq: use a temporary work area for validating
configuration
net_sched: sch_sfq: move the limit validation
net/sched/sch_sfq.c | 112 ++++++++++++++++++++++++++++----------------
1 file changed, 71 insertions(+), 41 deletions(-)
--
2.47.1
When transitioning from USB_ROLE_DEVICE to USB_ROLE_NONE, the code
assumed that the regulator should be disabled. However, if the regulator
is marked as always-on, regulator_is_enabled() continues to return true,
leading to an incorrect attempt to disable a regulator which is not
enabled.
This can result in warnings such as:
[ 250.155624] WARNING: CPU: 1 PID: 7326 at drivers/regulator/core.c:3004
_regulator_disable+0xe4/0x1a0
[ 250.155652] unbalanced disables for VIN_SYS_5V0
To fix this, we move the regulator control logic into
tegra186_xusb_padctl_id_override() function since it's directly related
to the ID override state. The regulator is now only disabled when the role
transitions from USB_ROLE_HOST to USB_ROLE_NONE, by checking the VBUS_ID
register. This ensures that regulator enable/disable operations are
properly balanced and only occur when actually transitioning to/from host
mode.
Fixes: 49d46e3c7e59 ("phy: tegra: xusb: Add set_mode support for UTMI phy on Tegra186")
Cc: stable(a)vger.kernel.org
Signed-off-by: Wayne Chang <waynec(a)nvidia.com>
---
drivers/phy/tegra/xusb-tegra186.c | 59 +++++++++++++++++++------------
1 file changed, 37 insertions(+), 22 deletions(-)
diff --git a/drivers/phy/tegra/xusb-tegra186.c b/drivers/phy/tegra/xusb-tegra186.c
index fae6242aa730..1b35d50821f7 100644
--- a/drivers/phy/tegra/xusb-tegra186.c
+++ b/drivers/phy/tegra/xusb-tegra186.c
@@ -774,13 +774,15 @@ static int tegra186_xusb_padctl_vbus_override(struct tegra_xusb_padctl *padctl,
}
static int tegra186_xusb_padctl_id_override(struct tegra_xusb_padctl *padctl,
- bool status)
+ struct tegra_xusb_usb2_port *port, bool status)
{
- u32 value;
+ u32 value, id_override;
+ int err = 0;
dev_dbg(padctl->dev, "%s id override\n", status ? "set" : "clear");
value = padctl_readl(padctl, USB2_VBUS_ID);
+ id_override = value & ID_OVERRIDE(~0);
if (status) {
if (value & VBUS_OVERRIDE) {
@@ -791,15 +793,35 @@ static int tegra186_xusb_padctl_id_override(struct tegra_xusb_padctl *padctl,
value = padctl_readl(padctl, USB2_VBUS_ID);
}
- value &= ~ID_OVERRIDE(~0);
- value |= ID_OVERRIDE_GROUNDED;
+ if (id_override != ID_OVERRIDE_GROUNDED) {
+ value &= ~ID_OVERRIDE(~0);
+ value |= ID_OVERRIDE_GROUNDED;
+ padctl_writel(padctl, value, USB2_VBUS_ID);
+
+ err = regulator_enable(port->supply);
+ if (err) {
+ dev_err(padctl->dev, "Failed to enable regulator: %d\n", err);
+ return err;
+ }
+ }
} else {
- value &= ~ID_OVERRIDE(~0);
- value |= ID_OVERRIDE_FLOATING;
+ if (id_override == ID_OVERRIDE_GROUNDED) {
+ /*
+ * The regulator is disabled only when the role transitions
+ * from USB_ROLE_HOST to USB_ROLE_NONE.
+ */
+ err = regulator_disable(port->supply);
+ if (err) {
+ dev_err(padctl->dev, "Failed to disable regulator: %d\n", err);
+ return err;
+ }
+
+ value &= ~ID_OVERRIDE(~0);
+ value |= ID_OVERRIDE_FLOATING;
+ padctl_writel(padctl, value, USB2_VBUS_ID);
+ }
}
- padctl_writel(padctl, value, USB2_VBUS_ID);
-
return 0;
}
@@ -818,27 +840,20 @@ static int tegra186_utmi_phy_set_mode(struct phy *phy, enum phy_mode mode,
if (mode == PHY_MODE_USB_OTG) {
if (submode == USB_ROLE_HOST) {
- tegra186_xusb_padctl_id_override(padctl, true);
-
- err = regulator_enable(port->supply);
+ err = tegra186_xusb_padctl_id_override(padctl, port, true);
+ if (err)
+ goto out;
} else if (submode == USB_ROLE_DEVICE) {
tegra186_xusb_padctl_vbus_override(padctl, true);
} else if (submode == USB_ROLE_NONE) {
- /*
- * When port is peripheral only or role transitions to
- * USB_ROLE_NONE from USB_ROLE_DEVICE, regulator is not
- * enabled.
- */
- if (regulator_is_enabled(port->supply))
- regulator_disable(port->supply);
-
- tegra186_xusb_padctl_id_override(padctl, false);
+ err = tegra186_xusb_padctl_id_override(padctl, port, false);
+ if (err)
+ goto out;
tegra186_xusb_padctl_vbus_override(padctl, false);
}
}
-
+out:
mutex_unlock(&padctl->lock);
-
return err;
}
--
2.25.1
* Sasha Levin (sashal(a)kernel.org) wrote:
> This is a note to let you know that I've just added the patch titled
>
> Bluetooth: MGMT: Remove unused mgmt_pending_find_data
>
> to the 6.12-stable tree which can be found at:
> http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=sum…
>
> The filename of the patch is:
> bluetooth-mgmt-remove-unused-mgmt_pending_find_data.patch
> and it can be found in the queue-6.12 subdirectory.
>
> If you, or anyone else, feels it should not be added to the stable tree,
> please let <stable(a)vger.kernel.org> know about it.
It's a cleanup only, so I wouldn't backport it unless it makes backporting
a useful patch easier.
Dave
>
>
> commit 17d285fbdeb9dabee6c6c348a528ac81ca65a6da
> Author: Dr. David Alan Gilbert <linux(a)treblig.org>
> Date: Mon Jan 27 21:37:15 2025 +0000
>
> Bluetooth: MGMT: Remove unused mgmt_pending_find_data
>
> [ Upstream commit 276af34d82f13bda0b2a4d9786c90b8bbf1cd064 ]
>
> mgmt_pending_find_data() last use was removed in 2021 by
> commit 5a7501374664 ("Bluetooth: hci_sync: Convert MGMT_OP_GET_CLOCK_INFO")
>
> Remove it.
>
> Signed-off-by: Dr. David Alan Gilbert <linux(a)treblig.org>
> Reviewed-by: Simon Horman <horms(a)kernel.org>
> Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz(a)intel.com>
> Stable-dep-of: 6fe26f694c82 ("Bluetooth: MGMT: Protect mgmt_pending list with its own lock")
> Signed-off-by: Sasha Levin <sashal(a)kernel.org>
>
> diff --git a/net/bluetooth/mgmt_util.c b/net/bluetooth/mgmt_util.c
> index 67db32a60c6a9..3713ff490c65d 100644
> --- a/net/bluetooth/mgmt_util.c
> +++ b/net/bluetooth/mgmt_util.c
> @@ -229,23 +229,6 @@ struct mgmt_pending_cmd *mgmt_pending_find(unsigned short channel, u16 opcode,
> return NULL;
> }
>
> -struct mgmt_pending_cmd *mgmt_pending_find_data(unsigned short channel,
> - u16 opcode,
> - struct hci_dev *hdev,
> - const void *data)
> -{
> - struct mgmt_pending_cmd *cmd;
> -
> - list_for_each_entry(cmd, &hdev->mgmt_pending, list) {
> - if (cmd->user_data != data)
> - continue;
> - if (cmd->opcode == opcode)
> - return cmd;
> - }
> -
> - return NULL;
> -}
> -
> void mgmt_pending_foreach(u16 opcode, struct hci_dev *hdev,
> void (*cb)(struct mgmt_pending_cmd *cmd, void *data),
> void *data)
> diff --git a/net/bluetooth/mgmt_util.h b/net/bluetooth/mgmt_util.h
> index bdf978605d5a8..f2ba994ab1d84 100644
> --- a/net/bluetooth/mgmt_util.h
> +++ b/net/bluetooth/mgmt_util.h
> @@ -54,10 +54,6 @@ int mgmt_cmd_complete(struct sock *sk, u16 index, u16 cmd, u8 status,
>
> struct mgmt_pending_cmd *mgmt_pending_find(unsigned short channel, u16 opcode,
> struct hci_dev *hdev);
> -struct mgmt_pending_cmd *mgmt_pending_find_data(unsigned short channel,
> - u16 opcode,
> - struct hci_dev *hdev,
> - const void *data);
> void mgmt_pending_foreach(u16 opcode, struct hci_dev *hdev,
> void (*cb)(struct mgmt_pending_cmd *cmd, void *data),
> void *data);
--
-----Open up your eyes, open up your mind, open up your code -------
/ Dr. David Alan Gilbert | Running GNU/Linux | Happy \
\ dave @ treblig.org | | In Hex /
\ _________________________|_____ http://www.treblig.org |_______/
* Sasha Levin (sashal(a)kernel.org) wrote:
> This is a note to let you know that I've just added the patch titled
>
> Bluetooth: MGMT: Remove unused mgmt_pending_find_data
>
> to the 6.6-stable tree which can be found at:
> http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=sum…
>
> The filename of the patch is:
> bluetooth-mgmt-remove-unused-mgmt_pending_find_data.patch
> and it can be found in the queue-6.6 subdirectory.
>
> If you, or anyone else, feels it should not be added to the stable tree,
> please let <stable(a)vger.kernel.org> know about it.
<rewinds, copies same message I did for 6.12 - please take this to mean all of them>
It's a cleanup only, so I wouldn't backport it unless it makes backporting
a useful patch easier.
Dave
>
>
>
> commit af31788b431f56d9b304d32701f1f9143aae8f95
> Author: Dr. David Alan Gilbert <linux(a)treblig.org>
> Date: Mon Jan 27 21:37:15 2025 +0000
>
> Bluetooth: MGMT: Remove unused mgmt_pending_find_data
>
> [ Upstream commit 276af34d82f13bda0b2a4d9786c90b8bbf1cd064 ]
>
> mgmt_pending_find_data() last use was removed in 2021 by
> commit 5a7501374664 ("Bluetooth: hci_sync: Convert MGMT_OP_GET_CLOCK_INFO")
>
> Remove it.
>
> Signed-off-by: Dr. David Alan Gilbert <linux(a)treblig.org>
> Reviewed-by: Simon Horman <horms(a)kernel.org>
> Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz(a)intel.com>
> Stable-dep-of: 6fe26f694c82 ("Bluetooth: MGMT: Protect mgmt_pending list with its own lock")
> Signed-off-by: Sasha Levin <sashal(a)kernel.org>
>
> diff --git a/net/bluetooth/mgmt_util.c b/net/bluetooth/mgmt_util.c
> index 17e32605d9b00..dba6a0d66500f 100644
> --- a/net/bluetooth/mgmt_util.c
> +++ b/net/bluetooth/mgmt_util.c
> @@ -229,23 +229,6 @@ struct mgmt_pending_cmd *mgmt_pending_find(unsigned short channel, u16 opcode,
> return NULL;
> }
>
> -struct mgmt_pending_cmd *mgmt_pending_find_data(unsigned short channel,
> - u16 opcode,
> - struct hci_dev *hdev,
> - const void *data)
> -{
> - struct mgmt_pending_cmd *cmd;
> -
> - list_for_each_entry(cmd, &hdev->mgmt_pending, list) {
> - if (cmd->user_data != data)
> - continue;
> - if (cmd->opcode == opcode)
> - return cmd;
> - }
> -
> - return NULL;
> -}
> -
> void mgmt_pending_foreach(u16 opcode, struct hci_dev *hdev,
> void (*cb)(struct mgmt_pending_cmd *cmd, void *data),
> void *data)
> diff --git a/net/bluetooth/mgmt_util.h b/net/bluetooth/mgmt_util.h
> index bdf978605d5a8..f2ba994ab1d84 100644
> --- a/net/bluetooth/mgmt_util.h
> +++ b/net/bluetooth/mgmt_util.h
> @@ -54,10 +54,6 @@ int mgmt_cmd_complete(struct sock *sk, u16 index, u16 cmd, u8 status,
>
> struct mgmt_pending_cmd *mgmt_pending_find(unsigned short channel, u16 opcode,
> struct hci_dev *hdev);
> -struct mgmt_pending_cmd *mgmt_pending_find_data(unsigned short channel,
> - u16 opcode,
> - struct hci_dev *hdev,
> - const void *data);
> void mgmt_pending_foreach(u16 opcode, struct hci_dev *hdev,
> void (*cb)(struct mgmt_pending_cmd *cmd, void *data),
> void *data);
--
-----Open up your eyes, open up your mind, open up your code -------
/ Dr. David Alan Gilbert | Running GNU/Linux | Happy \
\ dave @ treblig.org | | In Hex /
\ _________________________|_____ http://www.treblig.org |_______/
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+pCRyWTKLEOsc8BOmH73p…
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(a)google.com>
Closes: https://lore.kernel.org/linux-bcache/CAJhEC06F_AtrPgw2-7CvCqZgeStgCtitbD-ry…
Cc: stable(a)vger.kernel.org
Signed-off-by: Kuan-Wei Chiu <visitorckw(a)gmail.com>
---
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