| Message ID | 20190707223303.6755-9-digetx@gmail.com (mailing list archive) |
|---|---|
| State | Not Applicable, archived |
| Headers | show |
| Series | More improvements for Tegra30 devfreq driver | expand |
Hi Dmitiry, On 19. 7. 8. 오전 7:32, Dmitry Osipenko wrote: > There is no point in receiving of the notifications while governor is > stopped, let's keep them disabled like we do for the CPU freq-change > notifications. This also fixes a potential use-after-free bug if > notification happens after device's removal. > > Signed-off-by: Dmitry Osipenko <digetx@gmail.com> > --- > drivers/devfreq/tegra30-devfreq.c | 33 ++++++++++++++++++------------- > 1 file changed, 19 insertions(+), 14 deletions(-) > > diff --git a/drivers/devfreq/tegra30-devfreq.c b/drivers/devfreq/tegra30-devfreq.c > index 48a799fa5f63..d5d04c25023b 100644 > --- a/drivers/devfreq/tegra30-devfreq.c > +++ b/drivers/devfreq/tegra30-devfreq.c > @@ -576,6 +576,19 @@ static int tegra_actmon_start(struct tegra_devfreq *tegra) > actmon_writel(tegra, ACTMON_SAMPLING_PERIOD - 1, > ACTMON_GLB_PERIOD_CTRL); > > + /* > + * CLK notifications are needed in order to reconfigure the upper > + * consecutive watermark in accordance to the actual clock rate > + * to avoid unnecessary upper interrupts. > + */ > + err = clk_notifier_register(tegra->emc_clock, > + &tegra->clk_rate_change_nb); > + if (err) { > + dev_err(tegra->devfreq->dev.parent, > + "Failed to register rate change notifier\n"); > + return err; > + } > + > for (i = 0; i < ARRAY_SIZE(tegra->devices); i++) > tegra_actmon_configure_device(tegra, &tegra->devices[i]); > > @@ -602,6 +615,8 @@ static int tegra_actmon_start(struct tegra_devfreq *tegra) > for (i = 0; i < ARRAY_SIZE(tegra->devices); i++) > tegra_actmon_stop_device(&tegra->devices[i]); > > + clk_notifier_unregister(tegra->emc_clock, &tegra->clk_rate_change_nb); > + > return err; > } > > @@ -618,6 +633,8 @@ static void tegra_actmon_stop(struct tegra_devfreq *tegra) > > for (i = 0; i < ARRAY_SIZE(tegra->devices); i++) > tegra_actmon_stop_device(&tegra->devices[i]); > + > + clk_notifier_unregister(tegra->emc_clock, &tegra->clk_rate_change_nb); > } > > static int tegra_devfreq_target(struct device *dev, unsigned long *freq, > @@ -862,22 +879,14 @@ static int tegra_devfreq_probe(struct platform_device *pdev) > > platform_set_drvdata(pdev, tegra); > > + tegra->clk_rate_change_nb.notifier_call = tegra_actmon_clk_notify_cb; > tegra->cpu_rate_change_nb.notifier_call = tegra_actmon_cpu_notify_cb; > INIT_WORK(&tegra->update_work, tegra_actmon_delayed_update); > > - tegra->clk_rate_change_nb.notifier_call = tegra_actmon_clk_notify_cb; > - err = clk_notifier_register(tegra->emc_clock, > - &tegra->clk_rate_change_nb); > - if (err) { > - dev_err(&pdev->dev, > - "Failed to register rate change notifier\n"); > - goto remove_opps; > - } > - > err = devfreq_add_governor(&tegra_devfreq_governor); > if (err) { > dev_err(&pdev->dev, "Failed to add governor: %d\n", err); > - goto unreg_notifier; > + goto remove_opps; > } > > tegra_devfreq_profile.initial_freq = clk_get_rate(tegra->emc_clock); > @@ -893,9 +902,6 @@ static int tegra_devfreq_probe(struct platform_device *pdev) > remove_governor: > devfreq_remove_governor(&tegra_devfreq_governor); > > -unreg_notifier: > - clk_notifier_unregister(tegra->emc_clock, &tegra->clk_rate_change_nb); > - > remove_opps: > dev_pm_opp_remove_all_dynamic(&pdev->dev); > > @@ -912,7 +918,6 @@ static int tegra_devfreq_remove(struct platform_device *pdev) > devfreq_remove_device(tegra->devfreq); > devfreq_remove_governor(&tegra_devfreq_governor); > > - clk_notifier_unregister(tegra->emc_clock, &tegra->clk_rate_change_nb); > dev_pm_opp_remove_all_dynamic(&pdev->dev); > > reset_control_reset(tegra->reset); > Reviewed-by: Chanwoo Choi <cw00.choi@samsung.com>
diff --git a/drivers/devfreq/tegra30-devfreq.c b/drivers/devfreq/tegra30-devfreq.c index 48a799fa5f63..d5d04c25023b 100644 --- a/drivers/devfreq/tegra30-devfreq.c +++ b/drivers/devfreq/tegra30-devfreq.c @@ -576,6 +576,19 @@ static int tegra_actmon_start(struct tegra_devfreq *tegra) actmon_writel(tegra, ACTMON_SAMPLING_PERIOD - 1, ACTMON_GLB_PERIOD_CTRL); + /* + * CLK notifications are needed in order to reconfigure the upper + * consecutive watermark in accordance to the actual clock rate + * to avoid unnecessary upper interrupts. + */ + err = clk_notifier_register(tegra->emc_clock, + &tegra->clk_rate_change_nb); + if (err) { + dev_err(tegra->devfreq->dev.parent, + "Failed to register rate change notifier\n"); + return err; + } + for (i = 0; i < ARRAY_SIZE(tegra->devices); i++) tegra_actmon_configure_device(tegra, &tegra->devices[i]); @@ -602,6 +615,8 @@ static int tegra_actmon_start(struct tegra_devfreq *tegra) for (i = 0; i < ARRAY_SIZE(tegra->devices); i++) tegra_actmon_stop_device(&tegra->devices[i]); + clk_notifier_unregister(tegra->emc_clock, &tegra->clk_rate_change_nb); + return err; } @@ -618,6 +633,8 @@ static void tegra_actmon_stop(struct tegra_devfreq *tegra) for (i = 0; i < ARRAY_SIZE(tegra->devices); i++) tegra_actmon_stop_device(&tegra->devices[i]); + + clk_notifier_unregister(tegra->emc_clock, &tegra->clk_rate_change_nb); } static int tegra_devfreq_target(struct device *dev, unsigned long *freq, @@ -862,22 +879,14 @@ static int tegra_devfreq_probe(struct platform_device *pdev) platform_set_drvdata(pdev, tegra); + tegra->clk_rate_change_nb.notifier_call = tegra_actmon_clk_notify_cb; tegra->cpu_rate_change_nb.notifier_call = tegra_actmon_cpu_notify_cb; INIT_WORK(&tegra->update_work, tegra_actmon_delayed_update); - tegra->clk_rate_change_nb.notifier_call = tegra_actmon_clk_notify_cb; - err = clk_notifier_register(tegra->emc_clock, - &tegra->clk_rate_change_nb); - if (err) { - dev_err(&pdev->dev, - "Failed to register rate change notifier\n"); - goto remove_opps; - } - err = devfreq_add_governor(&tegra_devfreq_governor); if (err) { dev_err(&pdev->dev, "Failed to add governor: %d\n", err); - goto unreg_notifier; + goto remove_opps; } tegra_devfreq_profile.initial_freq = clk_get_rate(tegra->emc_clock); @@ -893,9 +902,6 @@ static int tegra_devfreq_probe(struct platform_device *pdev) remove_governor: devfreq_remove_governor(&tegra_devfreq_governor); -unreg_notifier: - clk_notifier_unregister(tegra->emc_clock, &tegra->clk_rate_change_nb); - remove_opps: dev_pm_opp_remove_all_dynamic(&pdev->dev); @@ -912,7 +918,6 @@ static int tegra_devfreq_remove(struct platform_device *pdev) devfreq_remove_device(tegra->devfreq); devfreq_remove_governor(&tegra_devfreq_governor); - clk_notifier_unregister(tegra->emc_clock, &tegra->clk_rate_change_nb); dev_pm_opp_remove_all_dynamic(&pdev->dev); reset_control_reset(tegra->reset);
There is no point in receiving of the notifications while governor is stopped, let's keep them disabled like we do for the CPU freq-change notifications. This also fixes a potential use-after-free bug if notification happens after device's removal. Signed-off-by: Dmitry Osipenko <digetx@gmail.com> --- drivers/devfreq/tegra30-devfreq.c | 33 ++++++++++++++++++------------- 1 file changed, 19 insertions(+), 14 deletions(-)