[PATCH v9 11/14] PCI: Use `pcie_wait_for_link_status' in `pcie_wait_for_link_delay'
From: "Maciej W. Rozycki" <macro@orcam.me.uk>
Date: 2023-06-11 17:20:52
Also in:
linux-pci, linux-rdma, linuxppc-dev, lkml
Remove a DLLLA status bit polling loop from `pcie_wait_for_link_delay' and call almost identical code in `pcie_wait_for_link_status' instead. This reduces the lower bound on the polling interval from 10ms to 1ms, possibly increasing the CPU load on the system in favour to reducing the wait time. Signed-off-by: Maciej W. Rozycki <macro@orcam.me.uk> --- New change in v9. --- drivers/pci/pci.c | 17 +++-------------- 1 file changed, 3 insertions(+), 14 deletions(-) linux-pcie-wait-for-link-delay-status.diff Index: linux-macro/drivers/pci/pci.c ===================================================================
--- linux-macro.orig/drivers/pci/pci.c
+++ linux-macro/drivers/pci/pci.c@@ -4889,16 +4889,14 @@ static bool pcie_wait_for_link_status(st static bool pcie_wait_for_link_delay(struct pci_dev *pdev, bool active, int delay) { - int timeout = PCIE_LINK_RETRAIN_TIMEOUT_MS; bool ret; - u16 lnk_status; /* * Some controllers might not implement link active reporting. In this * case, we wait for 1000 ms + any delay requested by the caller. */ if (!pdev->link_active_reporting) { - msleep(timeout + delay); + msleep(PCIE_LINK_RETRAIN_TIMEOUT_MS + delay); return true; }
@@ -4913,20 +4911,11 @@ static bool pcie_wait_for_link_delay(str */ if (active) msleep(20); - for (;;) { - pcie_capability_read_word(pdev, PCI_EXP_LNKSTA, &lnk_status); - ret = !!(lnk_status & PCI_EXP_LNKSTA_DLLLA); - if (ret == active) - break; - if (timeout <= 0) - break; - msleep(10); - timeout -= 10; - } + ret = pcie_wait_for_link_status(pdev, false, active); if (active && ret) msleep(delay); - return ret == active; + return ret; } /**