On Mon, Sep 19, 2011 at 14:08, Rafael J. Wysocki <rjw@xxxxxxx> wrote: > On Monday, September 19, 2011, Vincent Palatin wrote: >> On Sat, Sep 17, 2011 at 09:23, Alan Stern <stern@xxxxxxxxxxxxxxxxxxx> wrote: >> > On Fri, 16 Sep 2011, Vincent Palatin wrote: >> > >> >> When activating the PCI runtime PM on a laptop, my kernel log is filled with >> >> messages such as the following ones and can be hardly read to find interesting >> >> information: >> >> ehci_hcd 0000:00:1d.7: PME# disabled >> >> ehci_hcd 0000:00:1d.7: PCI INT A -> GSI 16 (level, low) -> IRQ 16 >> >> ehci_hcd 0000:00:1d.7: setting latency timer to 64 >> >> ehci_hcd 0000:00:1d.7: PCI INT A disabled >> >> ehci_hcd 0000:00:1d.7: PME# enabled >> >> ehci_hcd 0000:00:1d.7: BAR 0: set to [mem 0x92205000-0x922053ff] (PCI address [0x92205000-0x922053ff]) >> >> ehci_hcd 0000:00:1d.7: restoring config space at offset 0xf (was 0x100, writing 0x10b) >> >> ehci_hcd 0000:00:1d.7: restoring config space at offset 0x1 (was 0x2900000, writing 0x2900002) >> > ... >> > >> >> All those messages are triggered by the following cause, the laptop has a USB >> >> 3G modem with USB autosuspend activated. The USB device will wake up about >> >> every 30s to do some network related activities. Every time, the modem wakes >> >> up this triggers the wake up of the attached EHCI/PCI USB host controller >> >> which reconfigures its PCI interface, then everything go back to a suspended mode. >> >> >> >> Having the same 10 lines of log repeated is not really useful, but I probably >> >> cannot totally remove them since there are somewhat useful for PCI hotplug >> >> users and other PCI debugging. >> >> So, my proposal is to create a new dev_printk macro : "dev_printk_norpm" which >> >> outputs traces only when the device has not the runtime PM activated, >> >> and guard those traces with it. >> >> (cf the 2 patches in this thread as a PoC) >> > >> > Wouldn't it be easier just to change the existing messages to DEBUG >> > level? Or are they more important than that? >> >> Yes, I can simply replace all those printk by dev_dbg traces. For my >> use case, it's perfect. >> My main concern was people using PCI hotplug, I think, then, their log >> will remain mostly silent when inserting a card, I don't know if this >> is acceptable or not. > > I think they don't really need that information except for debugging, right? I think so. I will send a new patch with dev_dbg in replacement of the noisy printks for PCI messages. -- Vincent -- To unsubscribe from this list: send the line "unsubscribe linux-pci" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
