diff options
| author | Guan-Yu Lin <guanyulin@google.com> | 2026-04-01 12:32:17 +0000 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2026-04-11 14:29:50 +0200 |
| commit | d4cc15294d6dd295278b26dc222058c8e481504e (patch) | |
| tree | 42edcc0ab7ae32d9dc8526e7719b76a884bf394a /include | |
| parent | b490f0e477d26d29ed51e5dc47e3b9bd31bcb49f (diff) | |
usb: core: use dedicated spinlock for offload state
commit bd3d245b0fef571f93504904df62b8865b1c0d34 upstream.
Replace the coarse USB device lock with a dedicated offload_lock
spinlock to reduce contention during offload operations. Use
offload_pm_locked to synchronize with PM transitions and replace
the legacy offload_at_suspend flag.
Optimize usb_offload_get/put by switching from auto-resume/suspend
to pm_runtime_get_if_active(). This ensures offload state is only
modified when the device is already active, avoiding unnecessary
power transitions.
Cc: stable <stable@kernel.org>
Fixes: ef82a4803aab ("xhci: sideband: add api to trace sideband usage")
Signed-off-by: Guan-Yu Lin <guanyulin@google.com>
Tested-by: Hailong Liu <hailong.liu@oppo.com>
Acked-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Link: https://patch.msgid.link/20260401123238.3790062-2-guanyulin@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'include')
| -rw-r--r-- | include/linux/usb.h | 10 |
1 files changed, 8 insertions, 2 deletions
diff --git a/include/linux/usb.h b/include/linux/usb.h index 32e17626dfdc..2511f1e5b114 100644 --- a/include/linux/usb.h +++ b/include/linux/usb.h @@ -21,6 +21,7 @@ #include <linux/completion.h> /* for struct completion */ #include <linux/sched.h> /* for current && schedule_timeout */ #include <linux/mutex.h> /* for struct mutex */ +#include <linux/spinlock.h> /* for spinlock_t */ #include <linux/pm_runtime.h> /* for runtime PM */ struct usb_device; @@ -636,8 +637,9 @@ struct usb3_lpm_parameters { * @do_remote_wakeup: remote wakeup should be enabled * @reset_resume: needs reset instead of resume * @port_is_suspended: the upstream port is suspended (L2 or U3) - * @offload_at_suspend: offload activities during suspend is enabled. + * @offload_pm_locked: prevents offload_usage changes during PM transitions. * @offload_usage: number of offload activities happening on this usb device. + * @offload_lock: protects offload_usage and offload_pm_locked * @slot_id: Slot ID assigned by xHCI * @l1_params: best effor service latency for USB2 L1 LPM state, and L1 timeout. * @u1_params: exit latencies for USB3 U1 LPM state, and hub-initiated timeout. @@ -726,8 +728,9 @@ struct usb_device { unsigned do_remote_wakeup:1; unsigned reset_resume:1; unsigned port_is_suspended:1; - unsigned offload_at_suspend:1; + unsigned offload_pm_locked:1; int offload_usage; + spinlock_t offload_lock; enum usb_link_tunnel_mode tunnel_mode; struct device_link *usb4_link; @@ -849,6 +852,7 @@ static inline void usb_mark_last_busy(struct usb_device *udev) int usb_offload_get(struct usb_device *udev); int usb_offload_put(struct usb_device *udev); bool usb_offload_check(struct usb_device *udev); +void usb_offload_set_pm_locked(struct usb_device *udev, bool locked); #else static inline int usb_offload_get(struct usb_device *udev) @@ -857,6 +861,8 @@ static inline int usb_offload_put(struct usb_device *udev) { return 0; } static inline bool usb_offload_check(struct usb_device *udev) { return false; } +static inline void usb_offload_set_pm_locked(struct usb_device *udev, bool locked) +{ } #endif extern int usb_disable_lpm(struct usb_device *udev); |