PCI/VPD: Check for VPD access completion before checking for timeout

Previously we checked the timeout before checking the VPD access completion
bit.  On a very heavily loaded system this can cause VPD access to timeout.
Check the completion bit before checking the timeout.

Signed-off-by: Bert Kenward <bkenward@solarflare.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>

1 files changed, 5 insertions, 2 deletions

diff --git a/drivers/pci/vpd.c b/drivers/pci/vpd.c
index 8617565ba561..4963c2e2bd4c 100644
--- a/drivers/pci/vpd.c
+++ b/drivers/pci/vpd.c
@@ -146,7 +146,7 @@ static int pci_vpd_wait(struct pci_dev *dev)
         if (!vpd->busy)
                 return 0;
 
-        while (time_before(jiffies, timeout)) {
+        do {
                 ret = pci_user_read_config_word(dev, vpd->cap + PCI_VPD_ADDR,
                                                 &status);
                 if (ret < 0)
@@ -160,10 +160,13 @@ static int pci_vpd_wait(struct pci_dev *dev)
                 if (fatal_signal_pending(current))
                         return -EINTR;
 
+                if (time_after(jiffies, timeout))
+                        break;
+
                 usleep_range(10, max_sleep);
                 if (max_sleep < 1024)
                         max_sleep *= 2;
-        }
+        } while (true);
 
         pci_warn(dev, "VPD access failed.  This is likely a firmware bug on this device.  Contact the card vendor for a firmware update\n");
         return -ETIMEDOUT;