[+cc Rafael, linux-pm]
On Thu, May 21, 2020 at 11:13:49AM +0800, Dinghao Liu wrote:
> pm_runtime_get_sync() increments the runtime PM usage counter even
> when it returns an error code. Thus a pairing decrement is needed on
> the error handling path to keep the counter balanced.
I didn't realize there were so many drivers with the exact same issue.
Can we just squash these all into a single patch so we can see them
all together?
Hmm. There are over 1300 callers of pm_runtime_get_sync(), and it
looks like many of them have similar issues, i.e., they have a pattern
like this
ret = pm_runtime_get_sync(dev);
if (ret < 0)
return;
pm_runtime_put(dev);
where there is not a pm_runtime_put() to match every
pm_runtime_get_sync(). Random sample:
nds32_pmu_reserve_hardware
sata_rcar_probe
exynos_trng_probe
ks_sa_rng_probe
omap_aes_probe
sun8i_ss_probe
omap_aes_probe
zynq_gpio_probe
amdgpu_hwmon_show_power_avg
mtk_crtc_ddp_hw_init
...
Surely I'm missing something and these aren't all broken, right?
Maybe we could put together a coccinelle script to scan the tree for
this issue?
> Signed-off-by: Dinghao Liu <dinghao.liu@xxxxxxxxxx>
> ---
> drivers/pci/controller/dwc/pcie-tegra194.c | 5 ++---
> 1 file changed, 2 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/pci/controller/dwc/pcie-tegra194.c b/drivers/pci/controller/dwc/pcie-tegra194.c
> index ae30a2fd3716..2c0d2ce16b47 100644
> --- a/drivers/pci/controller/dwc/pcie-tegra194.c
> +++ b/drivers/pci/controller/dwc/pcie-tegra194.c
> @@ -1623,7 +1623,7 @@ static int tegra_pcie_config_rp(struct tegra_pcie_dw *pcie)
> ret = pinctrl_pm_select_default_state(dev);
> if (ret < 0) {
> dev_err(dev, "Failed to configure sideband pins: %d\n", ret);
> - goto fail_pinctrl;
> + goto fail_pm_get_sync;
> }
>
> tegra_pcie_init_controller(pcie);
> @@ -1650,9 +1650,8 @@ static int tegra_pcie_config_rp(struct tegra_pcie_dw *pcie)
>
> fail_host_init:
> tegra_pcie_deinit_controller(pcie);
> -fail_pinctrl:
> - pm_runtime_put_sync(dev);
> fail_pm_get_sync:
> + pm_runtime_put_sync(dev);
> pm_runtime_disable(dev);
> return ret;
> }
> --
> 2.17.1
>
