From 2a815b5ac374d670f347f2d3a39db07105715398 Mon Sep 17 00:00:00 2001 From: Rishi Mehta Date: Tue, 11 Mar 2014 13:51:33 -0700 Subject: [PATCH] [SCSI] vmw_pvscsi: Add support for I/O requests coalescing. This change allows pvscsi driver to coalesce I/O requests before issuing them. The number of I/O's coalesced can be dynamically configured based on the workload. Signed-off-by: Rishi Mehta Signed-off-by: Arvind Kumar Signed-off-by: James Bottomley --- drivers/scsi/vmw_pvscsi.c | 49 ++++++++++++++++++++++++++++++++++++--- drivers/scsi/vmw_pvscsi.h | 17 +++++++++++--- 2 files changed, 60 insertions(+), 6 deletions(-) diff --git a/drivers/scsi/vmw_pvscsi.c b/drivers/scsi/vmw_pvscsi.c index 7c5abd7f6c67..b92ea94be98f 100644 --- a/drivers/scsi/vmw_pvscsi.c +++ b/drivers/scsi/vmw_pvscsi.c @@ -72,6 +72,7 @@ struct pvscsi_adapter { bool use_msi; bool use_msix; bool use_msg; + bool use_req_threshold; spinlock_t hw_lock; @@ -109,6 +110,7 @@ static int pvscsi_cmd_per_lun = PVSCSI_DEFAULT_QUEUE_DEPTH; static bool pvscsi_disable_msi; static bool pvscsi_disable_msix; static bool pvscsi_use_msg = true; +static bool pvscsi_use_req_threshold = true; #define PVSCSI_RW (S_IRUSR | S_IWUSR) @@ -133,6 +135,10 @@ MODULE_PARM_DESC(disable_msix, "Disable MSI-X use in driver - (default=0)"); module_param_named(use_msg, pvscsi_use_msg, bool, PVSCSI_RW); MODULE_PARM_DESC(use_msg, "Use msg ring when available - (default=1)"); +module_param_named(use_req_threshold, pvscsi_use_req_threshold, + bool, PVSCSI_RW); +MODULE_PARM_DESC(use_req_threshold, "Use driver-based request coalescing if configured - (default=1)"); + static const struct pci_device_id pvscsi_pci_tbl[] = { { PCI_VDEVICE(VMWARE, PCI_DEVICE_ID_VMWARE_PVSCSI) }, { 0 } @@ -282,10 +288,15 @@ static int scsi_is_rw(unsigned char op) static void pvscsi_kick_io(const struct pvscsi_adapter *adapter, unsigned char op) { - if (scsi_is_rw(op)) - pvscsi_kick_rw_io(adapter); - else + if (scsi_is_rw(op)) { + struct PVSCSIRingsState *s = adapter->rings_state; + + if (!adapter->use_req_threshold || + s->reqProdIdx - s->reqConsIdx >= s->reqCallThreshold) + pvscsi_kick_rw_io(adapter); + } else { pvscsi_process_request_ring(adapter); + } } static void ll_adapter_reset(const struct pvscsi_adapter *adapter) @@ -1077,6 +1088,34 @@ static int pvscsi_setup_msg_workqueue(struct pvscsi_adapter *adapter) return 1; } +static bool pvscsi_setup_req_threshold(struct pvscsi_adapter *adapter, + bool enable) +{ + u32 val; + + if (!pvscsi_use_req_threshold) + return false; + + pvscsi_reg_write(adapter, PVSCSI_REG_OFFSET_COMMAND, + PVSCSI_CMD_SETUP_REQCALLTHRESHOLD); + val = pvscsi_reg_read(adapter, PVSCSI_REG_OFFSET_COMMAND_STATUS); + if (val == -1) { + printk(KERN_INFO "vmw_pvscsi: device does not support req_threshold\n"); + return false; + } else { + struct PVSCSICmdDescSetupReqCall cmd_msg = { 0 }; + cmd_msg.enable = enable; + printk(KERN_INFO + "vmw_pvscsi: %sabling reqCallThreshold\n", + enable ? "en" : "dis"); + pvscsi_write_cmd_desc(adapter, + PVSCSI_CMD_SETUP_REQCALLTHRESHOLD, + &cmd_msg, sizeof(cmd_msg)); + return pvscsi_reg_read(adapter, + PVSCSI_REG_OFFSET_COMMAND_STATUS) != 0; + } +} + static irqreturn_t pvscsi_isr(int irq, void *devp) { struct pvscsi_adapter *adapter = devp; @@ -1416,6 +1455,10 @@ static int pvscsi_probe(struct pci_dev *pdev, const struct pci_device_id *id) flags = IRQF_SHARED; } + adapter->use_req_threshold = pvscsi_setup_req_threshold(adapter, true); + printk(KERN_DEBUG "vmw_pvscsi: driver-based request coalescing %sabled\n", + adapter->use_req_threshold ? "en" : "dis"); + error = request_irq(adapter->irq, pvscsi_isr, flags, "vmw_pvscsi", adapter); if (error) { diff --git a/drivers/scsi/vmw_pvscsi.h b/drivers/scsi/vmw_pvscsi.h index a6437758384f..15a9ac68a50b 100644 --- a/drivers/scsi/vmw_pvscsi.h +++ b/drivers/scsi/vmw_pvscsi.h @@ -26,7 +26,7 @@ #include -#define PVSCSI_DRIVER_VERSION_STRING "1.0.3.0-k" +#define PVSCSI_DRIVER_VERSION_STRING "1.0.4.0-k" #define PVSCSI_MAX_NUM_SG_ENTRIES_PER_SEGMENT 128 @@ -117,8 +117,9 @@ enum PVSCSICommands { PVSCSI_CMD_CONFIG = 7, PVSCSI_CMD_SETUP_MSG_RING = 8, PVSCSI_CMD_DEVICE_UNPLUG = 9, + PVSCSI_CMD_SETUP_REQCALLTHRESHOLD = 10, - PVSCSI_CMD_LAST = 10 /* has to be last */ + PVSCSI_CMD_LAST = 11 /* has to be last */ }; /* @@ -141,6 +142,14 @@ struct PVSCSICmdDescConfigCmd { u32 _pad; } __packed; +/* + * Command descriptor for PVSCSI_CMD_SETUP_REQCALLTHRESHOLD -- + */ + +struct PVSCSICmdDescSetupReqCall { + u32 enable; +} __packed; + enum PVSCSIConfigPageType { PVSCSI_CONFIG_PAGE_CONTROLLER = 0x1958, PVSCSI_CONFIG_PAGE_PHY = 0x1959, @@ -261,7 +270,9 @@ struct PVSCSIRingsState { u32 cmpConsIdx; u32 cmpNumEntriesLog2; - u8 _pad[104]; + u32 reqCallThreshold; + + u8 _pad[100]; u32 msgProdIdx; u32 msgConsIdx; -- 2.34.1