From: Ahmed S. Darwish Date: Thu, 26 Nov 2020 13:29:42 +0000 (+0100) Subject: scsi: qla2xxx: Remove in_interrupt() from qla82xx-specific code X-Git-Tag: v5.15~2044^2~88 X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=8ac246bdd07a0f948f0e33eb4797bd2645cd8224;p=platform%2Fkernel%2Flinux-starfive.git scsi: qla2xxx: Remove in_interrupt() from qla82xx-specific code qla82xx_idc_lock() spins on a certain hardware state until it's updated. At the end of each spin, if in_interrupt() is true, it does 20 loops of cpu_relax(). Otherwise, it yields the CPU. While in_interrupt() is ill-defined and does not provide what the name suggests, it is not needed here: qla82xx_idc_lock() is always called from process context. Below is an analysis of its callers, in order of appearance: - qla_nx.c: qla82xx_device_bootstrap(), only called by qla82xx_device_state_handler(), has multiple msleep()s. - qla_nx.c: qla82xx_need_qsnt_handler(), has one second msleep() - qla_nx.c: qla82xx_wait_for_state_change(), one second msleep() - qla_nx.c: qla82xx_need_reset_handler(), can sleep up to 10 seconds - qla_nx.c: qla82xx_device_state_handler(), has multiple msleep()s - qla_nx.c: qla82xx_abort_isp(), if it's a qla82xx controller, calls qla82xx_device_state_handler(), which sleeps. It's also bound to isp_operations ->abort_isp() hook, where all the callers are in process context. - qla_nx.c: qla82xx_beacon_on(), bound to isp_operations ->beacon_on() hook. That hook is only called once, in a mutex locked context, from qla2x00_beacon_store(). - qla_nx.c: qla82xx_beacon_off(), bound to isp_operations ->beacon_off() hook. Like ->beacon_on(), it's only called once, in a mutex locked context, from qla2x00_beacon_store(). - qla_nx.c: qla82xx_fw_dump(), calls qla2x00_wait_for_chip_reset(), which has msleep() in a loop. It is bound to isp_operations ->fw_dump() hook. That hook *is* called from atomic context at qla_isr.c by multiple interrupt handlers. Nonetheless, it's other controllers interrupt handlers, and not the qla82xx. - qla82xx_msix_default() and qla82xx_msix_rsp_q() call qla24xx_process_response_queue() which doesn't implement the firmware dumping. - qla_attr.c: qla2x00_sysfs_write_fw_dump(), and qla2x00_sysfs_write_reset(), process-context sysfs ->write() hooks. - qla_os.c: qla2x00_probe_one(). PCI ->probe(), process context. - qla_os.c: qla2x00_clear_drv_active(), called solely from qla2x00_remove_one(), which is PCI ->remove() hook, process context. - qla_os.c: qla2x00_do_dpc(), kthread function, process context. Remove the in_interrupt() check. Change qla82xx_idc_lock() specification to a purely process-context function. Mark it with "Context: task, might sleep". Change qla82xx_idc_lock() implementation to sleep 100ms, instead of a schedule(), for each spin. This is more deterministic, and it matches the other qla models idc_lock() functions. Link: https://lore.kernel.org/r/20201126132952.2287996-5-bigeasy@linutronix.de Cc: Nilesh Javali Cc: Reviewed-by: Himanshu Madhani Reviewed-by: Daniel Wagner Signed-off-by: Ahmed S. Darwish Signed-off-by: Sebastian Andrzej Siewior Signed-off-by: Martin K. Petersen --- diff --git a/drivers/scsi/qla2xxx/qla_def.h b/drivers/scsi/qla2xxx/qla_def.h index ed9b10f..fe3c0e2 100644 --- a/drivers/scsi/qla2xxx/qla_def.h +++ b/drivers/scsi/qla2xxx/qla_def.h @@ -3296,8 +3296,10 @@ struct isp_operations { void (*fw_dump)(struct scsi_qla_host *vha); void (*mpi_fw_dump)(struct scsi_qla_host *, int); + /* Context: task, might sleep */ int (*beacon_on) (struct scsi_qla_host *); int (*beacon_off) (struct scsi_qla_host *); + void (*beacon_blink) (struct scsi_qla_host *); void *(*read_optrom)(struct scsi_qla_host *, void *, @@ -3308,7 +3310,10 @@ struct isp_operations { int (*get_flash_version) (struct scsi_qla_host *, void *); int (*start_scsi) (srb_t *); int (*start_scsi_mq) (srb_t *); + + /* Context: task, might sleep */ int (*abort_isp) (struct scsi_qla_host *); + int (*iospace_config)(struct qla_hw_data *); int (*initialize_adapter)(struct scsi_qla_host *); }; diff --git a/drivers/scsi/qla2xxx/qla_nx.c b/drivers/scsi/qla2xxx/qla_nx.c index b3ba0de..b2017f1 100644 --- a/drivers/scsi/qla2xxx/qla_nx.c +++ b/drivers/scsi/qla2xxx/qla_nx.c @@ -489,29 +489,26 @@ qla82xx_rd_32(struct qla_hw_data *ha, ulong off_in) return data; } -#define IDC_LOCK_TIMEOUT 100000000 +/* + * Context: task, might sleep + */ int qla82xx_idc_lock(struct qla_hw_data *ha) { - int i; - int done = 0, timeout = 0; + const int delay_ms = 100, timeout_ms = 2000; + int done, total = 0; - while (!done) { + might_sleep(); + + while (true) { /* acquire semaphore5 from PCI HW block */ done = qla82xx_rd_32(ha, QLA82XX_PCIE_REG(PCIE_SEM5_LOCK)); if (done == 1) break; - if (timeout >= IDC_LOCK_TIMEOUT) + if (WARN_ON_ONCE(total >= timeout_ms)) return -1; - timeout++; - - /* Yield CPU */ - if (!in_interrupt()) - schedule(); - else { - for (i = 0; i < 20; i++) - cpu_relax(); - } + total += delay_ms; + msleep(delay_ms); } return 0;