| Message ID | 20200927032829.11321-2-haifeng.zhao@intel.com (mailing list archive) |
|---|---|
| State | Superseded, archived |
| Headers | show |
| Series | Fix DPC hotplug race and enhance error handling | expand |
> +#ifdef CONFIG_PCIE_DPC > +static inline bool pci_wait_port_outdpc(struct pci_dev *pdev) > +{ > + u16 cap = pdev->dpc_cap, status; > + u16 loop = 0; > + > + if (!cap) { > + pci_WARN_ONCE(pdev, !cap, "No DPC capability initiated\n"); > + return false; > + } > + pci_read_config_word(pdev, cap + PCI_EXP_DPC_STATUS, &status); > + pci_dbg(pdev, "DPC status %x, cap %x\n", status, cap); > + while (status & PCI_EXP_DPC_STATUS_TRIGGER && loop < 100) { > + msleep(10); > + loop++; > + pci_read_config_word(pdev, cap + PCI_EXP_DPC_STATUS, &status); > + } > + if (!(status & PCI_EXP_DPC_STATUS_TRIGGER)) { > + pci_dbg(pdev, "Out of DPC %x, cost %d ms\n", status, loop*10); > + return true; > + } > + pci_dbg(pdev, "Timeout to wait port out of DPC status\n"); > + return false; > +} I don't think that there is any good reason to have this as an inline function.
Yep, I am think the same question, is there any other files better to put this function ? How about pci.c ? Thanks, Ethan -----Original Message----- From: Christoph Hellwig <hch@infradead.org> Sent: Sunday, September 27, 2020 2:24 PM To: Zhao, Haifeng <haifeng.zhao@intel.com> Cc: bhelgaas@google.com; oohall@gmail.com; ruscur@russell.cc; lukas@wunner.de; andriy.shevchenko@linux.intel.com; stuart.w.hayes@gmail.com; mr.nuke.me@gmail.com; mika.westerberg@linux.intel.com; linux-pci@vger.kernel.org; linux-kernel@vger.kernel.org; Jia, Pei P <pei.p.jia@intel.com>; ashok.raj@linux.intel.com; Kuppuswamy, Sathyanarayanan <sathyanarayanan.kuppuswamy@intel.com> Subject: Re: [PATCH 1/5 V2] PCI: define a function to check and wait till port finish DPC handling > +#ifdef CONFIG_PCIE_DPC > +static inline bool pci_wait_port_outdpc(struct pci_dev *pdev) { > + u16 cap = pdev->dpc_cap, status; > + u16 loop = 0; > + > + if (!cap) { > + pci_WARN_ONCE(pdev, !cap, "No DPC capability initiated\n"); > + return false; > + } > + pci_read_config_word(pdev, cap + PCI_EXP_DPC_STATUS, &status); > + pci_dbg(pdev, "DPC status %x, cap %x\n", status, cap); > + while (status & PCI_EXP_DPC_STATUS_TRIGGER && loop < 100) { > + msleep(10); > + loop++; > + pci_read_config_word(pdev, cap + PCI_EXP_DPC_STATUS, &status); > + } > + if (!(status & PCI_EXP_DPC_STATUS_TRIGGER)) { > + pci_dbg(pdev, "Out of DPC %x, cost %d ms\n", status, loop*10); > + return true; > + } > + pci_dbg(pdev, "Timeout to wait port out of DPC status\n"); > + return false; > +} I don't think that there is any good reason to have this as an inline function.
Fixed this concern by moving the function to DPC driver and its declaration to pci.h. see v5 Thanks, Ethan On Sun, Sep 27, 2020 at 2:27 PM Christoph Hellwig <hch@infradead.org> wrote: > > > +#ifdef CONFIG_PCIE_DPC > > +static inline bool pci_wait_port_outdpc(struct pci_dev *pdev) > > +{ > > + u16 cap = pdev->dpc_cap, status; > > + u16 loop = 0; > > + > > + if (!cap) { > > + pci_WARN_ONCE(pdev, !cap, "No DPC capability initiated\n"); > > + return false; > > + } > > + pci_read_config_word(pdev, cap + PCI_EXP_DPC_STATUS, &status); > > + pci_dbg(pdev, "DPC status %x, cap %x\n", status, cap); > > + while (status & PCI_EXP_DPC_STATUS_TRIGGER && loop < 100) { > > + msleep(10); > > + loop++; > > + pci_read_config_word(pdev, cap + PCI_EXP_DPC_STATUS, &status); > > + } > > + if (!(status & PCI_EXP_DPC_STATUS_TRIGGER)) { > > + pci_dbg(pdev, "Out of DPC %x, cost %d ms\n", status, loop*10); > > + return true; > > + } > > + pci_dbg(pdev, "Timeout to wait port out of DPC status\n"); > > + return false; > > +} > > I don't think that there is any good reason to have this as an > inline function.
diff --git a/include/linux/pci.h b/include/linux/pci.h index 835530605c0d..5beb76c6ae26 100644 --- a/include/linux/pci.h +++ b/include/linux/pci.h @@ -38,6 +38,7 @@ #include <linux/interrupt.h> #include <linux/io.h> #include <linux/resource_ext.h> +#include <linux/delay.h> #include <uapi/linux/pci.h> #include <linux/pci_ids.h> @@ -2427,4 +2428,34 @@ void pci_uevent_ers(struct pci_dev *pdev, enum pci_ers_result err_type); WARN_ONCE(condition, "%s %s: " fmt, \ dev_driver_string(&(pdev)->dev), pci_name(pdev), ##arg) +#ifdef CONFIG_PCIE_DPC +static inline bool pci_wait_port_outdpc(struct pci_dev *pdev) +{ + u16 cap = pdev->dpc_cap, status; + u16 loop = 0; + + if (!cap) { + pci_WARN_ONCE(pdev, !cap, "No DPC capability initiated\n"); + return false; + } + pci_read_config_word(pdev, cap + PCI_EXP_DPC_STATUS, &status); + pci_dbg(pdev, "DPC status %x, cap %x\n", status, cap); + while (status & PCI_EXP_DPC_STATUS_TRIGGER && loop < 100) { + msleep(10); + loop++; + pci_read_config_word(pdev, cap + PCI_EXP_DPC_STATUS, &status); + } + if (!(status & PCI_EXP_DPC_STATUS_TRIGGER)) { + pci_dbg(pdev, "Out of DPC %x, cost %d ms\n", status, loop*10); + return true; + } + pci_dbg(pdev, "Timeout to wait port out of DPC status\n"); + return false; +} +#else +static inline bool pci_wait_port_outdpc(struct pci_dev *pdev) +{ + return true; +} +#endif #endif /* LINUX_PCI_H */