From 6fc5d789512f7c1a33cbfd420d68d001e899b0de Mon Sep 17 00:00:00 2001 From: Lyude Paul Date: Tue, 20 Nov 2018 19:37:17 -0500 Subject: [PATCH] drm/i915: Synchronize hpd work in i915_hpd_storm_ctl_show() MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit While trying to add a chamelium test for short HPD IRQs, I ran into issues where a hotplug storm would be triggered, but the point at which it would be reported by the kernel would be after igt actually finished checking i915_hpd_storm_ctl's status. So, fix this by simply synchronizing our IRQ work, dig_port_work, and hotplug_work before printing out the HPD storm status in i915_hpd_storm_ctl_show(). Signed-off-by: Lyude Paul Cc: Ville Syrjälä Reviewed-by: Daniel Vetter Link: https://patchwork.freedesktop.org/patch/msgid/20181121003718.17704-1-lyude@redhat.com --- drivers/gpu/drm/i915/i915_debugfs.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/drivers/gpu/drm/i915/i915_debugfs.c b/drivers/gpu/drm/i915/i915_debugfs.c index 7f455bca528e..c120d87df594 100644 --- a/drivers/gpu/drm/i915/i915_debugfs.c +++ b/drivers/gpu/drm/i915/i915_debugfs.c @@ -4592,6 +4592,13 @@ static int i915_hpd_storm_ctl_show(struct seq_file *m, void *data) struct drm_i915_private *dev_priv = m->private; struct i915_hotplug *hotplug = &dev_priv->hotplug; + /* Synchronize with everything first in case there's been an HPD + * storm, but we haven't finished handling it in the kernel yet + */ + synchronize_irq(dev_priv->drm.irq); + flush_work(&dev_priv->hotplug.dig_port_work); + flush_work(&dev_priv->hotplug.hotplug_work); + seq_printf(m, "Threshold: %d\n", hotplug->hpd_storm_threshold); seq_printf(m, "Detected: %s\n", yesno(delayed_work_pending(&hotplug->reenable_work)));