Re: [PATCH net-next 1/8] bnxt_en: Do not call sleeping hwmon_notify_event() from NAPI
flat view
From: Guenter Roeck <linux@roeck-us.net>
Date: 2023-10-22 15:52:04
On 10/20/23 14:27, Michael Chan wrote:
From: Kalesh AP <kalesh-anakkur.purayil@broadcom.com>
Defer hwmon_notify_event() to bnxt_sp_task() workqueue because
hwmon_notify_event() can try to acquire a mutex shown in the stack trace
below. Modify bnxt_event_error_report() to return true if we need to
schedule bnxt_sp_task() to notify hwmon.
__schedule+0x68/0x520
hwmon_notify_event+0xe8/0x114
schedule+0x60/0xe0
schedule_preempt_disabled+0x28/0x40
__mutex_lock.constprop.0+0x534/0x550
__mutex_lock_slowpath+0x18/0x20
mutex_lock+0x5c/0x70
kobject_uevent_env+0x2f4/0x3d0
kobject_uevent+0x10/0x20
hwmon_notify_event+0x94/0x114
bnxt_hwmon_notify_event+0x40/0x70 [bnxt_en]
bnxt_event_error_report+0x260/0x290 [bnxt_en]
bnxt_async_event_process.isra.0+0x250/0x850 [bnxt_en]
bnxt_hwrm_handler.isra.0+0xc8/0x120 [bnxt_en]
bnxt_poll_p5+0x150/0x350 [bnxt_en]
__napi_poll+0x3c/0x210
net_rx_action+0x308/0x3b0
__do_softirq+0x120/0x3e0
Cc: Guenter Roeck <linux@roeck-us.net>
Fixes: a19b4801457b ("bnxt_en: Event handler for Thermal event")
Signed-off-by: Kalesh AP <kalesh-anakkur.purayil@broadcom.com>
Signed-off-by: Michael Chan <michael.chan@broadcom.com>Reviewed-by: Guenter Roeck <linux@roeck-us.net>
quoted hunk ↗ jump to hunk
--- drivers/net/ethernet/broadcom/bnxt/bnxt.c | 17 ++++++++++++----- drivers/net/ethernet/broadcom/bnxt/bnxt.h | 2 ++ drivers/net/ethernet/broadcom/bnxt/bnxt_hwmon.c | 4 ++-- drivers/net/ethernet/broadcom/bnxt/bnxt_hwmon.h | 4 ++-- 4 files changed, 18 insertions(+), 9 deletions(-)diff --git a/drivers/net/ethernet/broadcom/bnxt/bnxt.c b/drivers/net/ethernet/broadcom/bnxt/bnxt.c index 16eb7a7af970..7837e22f237b 100644 --- a/drivers/net/ethernet/broadcom/bnxt/bnxt.c +++ b/drivers/net/ethernet/broadcom/bnxt/bnxt.c@@ -2147,7 +2147,8 @@ static u16 bnxt_agg_ring_id_to_grp_idx(struct bnxt *bp, u16 ring_id) ASYNC_EVENT_CMPL_ERROR_REPORT_THERMAL_EVENT_DATA1_TRANSITION_DIR) ==\ ASYNC_EVENT_CMPL_ERROR_REPORT_THERMAL_EVENT_DATA1_TRANSITION_DIR_INCREASING) -static void bnxt_event_error_report(struct bnxt *bp, u32 data1, u32 data2) +/* Return true if the workqueue has to be scheduled */ +static bool bnxt_event_error_report(struct bnxt *bp, u32 data1, u32 data2) { u32 err_type = BNXT_EVENT_ERROR_REPORT_TYPE(data1);@@ -2182,7 +2183,7 @@ static void bnxt_event_error_report(struct bnxt *bp, u32 data1, u32 data2) break; default: netdev_err(bp->dev, "Unknown Thermal threshold type event\n"); - return; + return false; } if (EVENT_DATA1_THERMAL_THRESHOLD_DIR_INCREASING(data1)) dir_str = "above";@@ -2193,14 +2194,16 @@ static void bnxt_event_error_report(struct bnxt *bp, u32 data1, u32 data2) netdev_warn(bp->dev, "Temperature (In Celsius), Current: %lu, threshold: %lu\n", BNXT_EVENT_THERMAL_CURRENT_TEMP(data2), BNXT_EVENT_THERMAL_THRESHOLD_TEMP(data2)); - bnxt_hwmon_notify_event(bp, type); - break; + bp->thermal_threshold_type = type; + set_bit(BNXT_THERMAL_THRESHOLD_SP_EVENT, &bp->sp_event); + return true; } default: netdev_err(bp->dev, "FW reported unknown error type %u\n", err_type); break; } + return false; } #define BNXT_GET_EVENT_PORT(data) \@@ -2401,7 +2404,8 @@ static int bnxt_async_event_process(struct bnxt *bp, goto async_event_process_exit; } case ASYNC_EVENT_CMPL_EVENT_ID_ERROR_REPORT: { - bnxt_event_error_report(bp, data1, data2); + if (bnxt_event_error_report(bp, data1, data2)) + break; goto async_event_process_exit; } case ASYNC_EVENT_CMPL_EVENT_ID_PHC_UPDATE: {@@ -12085,6 +12089,9 @@ static void bnxt_sp_task(struct work_struct *work) if (test_and_clear_bit(BNXT_FW_ECHO_REQUEST_SP_EVENT, &bp->sp_event)) bnxt_fw_echo_reply(bp); + if (test_and_clear_bit(BNXT_THERMAL_THRESHOLD_SP_EVENT, &bp->sp_event)) + bnxt_hwmon_notify_event(bp); + /* These functions below will clear BNXT_STATE_IN_SP_TASK. They * must be the last functions to be called before exiting. */diff --git a/drivers/net/ethernet/broadcom/bnxt/bnxt.h b/drivers/net/ethernet/broadcom/bnxt/bnxt.h index 9ce0193798d4..80846c3ca9fc 100644 --- a/drivers/net/ethernet/broadcom/bnxt/bnxt.h +++ b/drivers/net/ethernet/broadcom/bnxt/bnxt.h@@ -2094,6 +2094,7 @@ struct bnxt { #define BNXT_FW_RESET_NOTIFY_SP_EVENT 18 #define BNXT_FW_EXCEPTION_SP_EVENT 19 #define BNXT_LINK_CFG_CHANGE_SP_EVENT 21 +#define BNXT_THERMAL_THRESHOLD_SP_EVENT 22 #define BNXT_FW_ECHO_REQUEST_SP_EVENT 23 struct delayed_work fw_reset_task;@@ -2196,6 +2197,7 @@ struct bnxt { u8 fatal_thresh_temp; u8 shutdown_thresh_temp; #endif + u32 thermal_threshold_type; enum board_idx board_idx; };diff --git a/drivers/net/ethernet/broadcom/bnxt/bnxt_hwmon.c b/drivers/net/ethernet/broadcom/bnxt/bnxt_hwmon.c index e48094043c3b..669d24ba0e87 100644 --- a/drivers/net/ethernet/broadcom/bnxt/bnxt_hwmon.c +++ b/drivers/net/ethernet/broadcom/bnxt/bnxt_hwmon.c@@ -18,14 +18,14 @@ #include "bnxt_hwrm.h" #include "bnxt_hwmon.h" -void bnxt_hwmon_notify_event(struct bnxt *bp, u32 type) +void bnxt_hwmon_notify_event(struct bnxt *bp) { u32 attr; if (!bp->hwmon_dev) return; - switch (type) { + switch (bp->thermal_threshold_type) { case ASYNC_EVENT_CMPL_ERROR_REPORT_THERMAL_EVENT_DATA1_THRESHOLD_TYPE_WARN: attr = hwmon_temp_max_alarm; break;diff --git a/drivers/net/ethernet/broadcom/bnxt/bnxt_hwmon.h b/drivers/net/ethernet/broadcom/bnxt/bnxt_hwmon.h index 76d9f599ebc0..de54a562e06a 100644 --- a/drivers/net/ethernet/broadcom/bnxt/bnxt_hwmon.h +++ b/drivers/net/ethernet/broadcom/bnxt/bnxt_hwmon.h@@ -11,11 +11,11 @@ #define BNXT_HWMON_H #ifdef CONFIG_BNXT_HWMON -void bnxt_hwmon_notify_event(struct bnxt *bp, u32 type); +void bnxt_hwmon_notify_event(struct bnxt *bp); void bnxt_hwmon_uninit(struct bnxt *bp); void bnxt_hwmon_init(struct bnxt *bp); #else -static inline void bnxt_hwmon_notify_event(struct bnxt *bp, u32 type) +static inline void bnxt_hwmon_notify_event(struct bnxt *bp) { }