From 5553ba2be0f3e3741e1a885a33d2b89921f9fd48 Mon Sep 17 00:00:00 2001 From: Edmund Nadolski Date: Thu, 19 May 2011 11:59:10 +0000 Subject: [PATCH] isci: replace isci_timer list with proper embedded timers Rather than preallocating a list of timers and doling them out at runtime, embed a struct timerlist in each object that needs one. A struct sci_timer interface is introduced to manage the timer cancellation semantics which currently need to guarantee the timer is cancelled while holding spin_lock(ihost->scic_lock). Since the timeout functions also need to acquire the lock it currently prevents the driver from using del_timer_sync() for runtime cancellations. del_timer_sync() is used however before the objects go out of scope. Signed-off-by: Edmund Nadolski Signed-off-by: Dan Williams --- drivers/scsi/isci/host.c | 7 +++++++ drivers/scsi/isci/isci.h | 33 +++++++++++++++++++++++++++++++++ drivers/scsi/isci/port.c | 39 ++++++++++++++++++--------------------- drivers/scsi/isci/port.h | 6 ++---- 4 files changed, 60 insertions(+), 25 deletions(-) diff --git a/drivers/scsi/isci/host.c b/drivers/scsi/isci/host.c index 6cd7648197e1..a3269b6fa225 100644 --- a/drivers/scsi/isci/host.c +++ b/drivers/scsi/isci/host.c @@ -1359,6 +1359,13 @@ void isci_host_deinit(struct isci_host *ihost) wait_for_stop(ihost); scic_controller_reset(&ihost->sci); + + /* Cancel any/all outstanding port timers */ + for (i = 0; i < ihost->sci.logical_port_entries; i++) { + struct scic_sds_port *sci_port = &ihost->ports[i].sci; + del_timer_sync(&sci_port->timer.timer); + } + isci_timer_list_destroy(ihost); } diff --git a/drivers/scsi/isci/isci.h b/drivers/scsi/isci/isci.h index 69826eac97b5..2fe5557d8590 100644 --- a/drivers/scsi/isci/isci.h +++ b/drivers/scsi/isci/isci.h @@ -551,4 +551,37 @@ extern unsigned char max_concurr_spinup; irqreturn_t isci_msix_isr(int vec, void *data); irqreturn_t isci_intx_isr(int vec, void *data); irqreturn_t isci_error_isr(int vec, void *data); + +/* + * Each timer is associated with a cancellation flag that is set when + * del_timer() is called and checked in the timer callback function. This + * is needed since del_timer_sync() cannot be called with scic_lock held. + * For deinit however, del_timer_sync() is used without holding the lock. + */ +struct sci_timer { + struct timer_list timer; + bool cancel; +}; + +static inline +void sci_init_timer(struct sci_timer *tmr, void (*fn)(unsigned long)) +{ + tmr->timer.function = fn; + tmr->timer.data = (unsigned long) tmr; + tmr->cancel = 0; + init_timer(&tmr->timer); +} + +static inline void sci_mod_timer(struct sci_timer *tmr, unsigned long msec) +{ + tmr->cancel = 0; + mod_timer(&tmr->timer, jiffies + msecs_to_jiffies(msec)); +} + +static inline void sci_del_timer(struct sci_timer *tmr) +{ + tmr->cancel = 1; + del_timer(&tmr->timer); +} + #endif /* __ISCI_H__ */ diff --git a/drivers/scsi/isci/port.c b/drivers/scsi/isci/port.c index 3050415e228d..3da9048b45b7 100644 --- a/drivers/scsi/isci/port.c +++ b/drivers/scsi/isci/port.c @@ -926,17 +926,19 @@ bool scic_sds_port_link_detected( return true; } -/** - * This method is provided to timeout requests for port operations. Mostly its - * for the port reset operation. - * - * - */ -static void scic_sds_port_timeout_handler(void *port) +static void port_timeout(unsigned long data) { - struct scic_sds_port *sci_port = port; + struct sci_timer *tmr = (struct sci_timer *)data; + struct scic_sds_port *sci_port = container_of(tmr, typeof(*sci_port), timer); + struct isci_host *ihost = scic_to_ihost(sci_port->owning_controller); + unsigned long flags; u32 current_state; + spin_lock_irqsave(&ihost->scic_lock, flags); + + if (tmr->cancel) + goto done; + current_state = sci_base_state_machine_get_state(&sci_port->state_machine); if (current_state == SCI_BASE_PORT_STATE_RESETTING) { @@ -965,6 +967,9 @@ static void scic_sds_port_timeout_handler(void *port) "%s: SCIC Port 0x%p is processing a timeout operation " "in state %d.\n", __func__, sci_port, current_state); } + +done: + spin_unlock_irqrestore(&ihost->scic_lock, flags); } /* --------------------------------------------------------------------------- */ @@ -1259,7 +1264,6 @@ static void scic_sds_port_ready_substate_configuring_exit(struct sci_base_state_ enum sci_status scic_sds_port_start(struct scic_sds_port *sci_port) { struct scic_sds_controller *scic = sci_port->owning_controller; - struct isci_host *ihost = scic_to_ihost(scic); enum sci_status status = SCI_SUCCESS; enum scic_sds_port_states state; u32 phy_mask; @@ -1280,14 +1284,6 @@ enum sci_status scic_sds_port_start(struct scic_sds_port *sci_port) return SCI_FAILURE_UNSUPPORTED_PORT_CONFIGURATION; } - sci_port->timer_handle = - isci_timer_create(ihost, - sci_port, - scic_sds_port_timeout_handler); - - if (!sci_port->timer_handle) - return SCI_FAILURE_INSUFFICIENT_RESOURCES; - if (sci_port->reserved_rni == SCU_DUMMY_INDEX) { u16 rni = scic_sds_remote_node_table_allocate_remote_node( &scic->available_remote_nodes, 1); @@ -1390,7 +1386,7 @@ static enum sci_status scic_port_hard_reset(struct scic_sds_port *sci_port, u32 if (status != SCI_SUCCESS) return status; - isci_timer_start(sci_port->timer_handle, timeout); + sci_mod_timer(&sci_port->timer, timeout); sci_port->not_ready_reason = SCIC_PORT_NOT_READY_HARD_RESET_REQUESTED; port_state_machine_change(sci_port, @@ -1757,14 +1753,14 @@ static void scic_sds_port_resetting_state_exit(struct sci_base_state_machine *sm { struct scic_sds_port *sci_port = container_of(sm, typeof(*sci_port), state_machine); - isci_timer_stop(sci_port->timer_handle); + sci_del_timer(&sci_port->timer); } static void scic_sds_port_stopping_state_exit(struct sci_base_state_machine *sm) { struct scic_sds_port *sci_port = container_of(sm, typeof(*sci_port), state_machine); - isci_timer_stop(sci_port->timer_handle); + sci_del_timer(&sci_port->timer); scic_sds_port_destroy_dummy_resources(sci_port); } @@ -1831,7 +1827,8 @@ void scic_sds_port_construct(struct scic_sds_port *sci_port, u8 index, sci_port->reserved_rni = SCU_DUMMY_INDEX; sci_port->reserved_tci = SCU_DUMMY_INDEX; - sci_port->timer_handle = NULL; + sci_init_timer(&sci_port->timer, port_timeout); + sci_port->port_task_scheduler_registers = NULL; for (index = 0; index < SCI_MAX_PHYS; index++) diff --git a/drivers/scsi/isci/port.h b/drivers/scsi/isci/port.h index af540e5c03a0..9a6912855fc1 100644 --- a/drivers/scsi/isci/port.h +++ b/drivers/scsi/isci/port.h @@ -139,10 +139,8 @@ struct scic_sds_port { */ struct scic_sds_controller *owning_controller; - /** - * This field contains the port start/stop timer handle. - */ - void *timer_handle; + /* timer used for port start/stop operations */ + struct sci_timer timer; /** * This field is the pointer to the port task scheduler registers -- 2.20.1