Bernhard Kaindl 7acf631889 igb: remove blocking phy read from inside spinlock ... Remove a source of latency spikes (in my case up to 10ms) by not calling code that uses mdelay() for feeding a phy statistic (rx errors for idle symbols - not data -> idle_errors) while being called with a spinlock held. As idle_errors isn't read, this patch only removes unused code and data. Later, more complicated changes may be applied to address the spinlock and allow for some PHY diagnostics by harvesting this PHY stats register fully. This patch is designed to fix the issue and be safe for longterm/stable. For the Intel e1000e driver, the same change was applied in 2008 with commit 23033fad5b ("e1000e: remove phy read from inside spinlock"). The mdelay is triggered by HW/SW semaphores, thus it depends on the HW. I've HW that triggers it even when idle. Others may trigger it only e.g. when Ethernet ports aquire or loose the link or on ifconfig up / down. We've noticed this first from delays in frame rx/tx due to the mdelay(). Example command for checking if the issue is triggered: cyclictest -Smp1 (Look for occasional "Max:" values > 4000 or use -b 4000 to stop if greater) It was observed with I350 ports connected to other I350 ports, but not if driver and EEPROM was modified to run the I350 in EEPROM-less mode. phy_stats.idle_errors and .receive_errors (isn't touched) occupy 64 not used bits in the adapter struct: Their allocation may be removed as well. Cc: Carolyn Wyborny <carolyn.wyborny@intel.com> Cc: Todd Fujinaka <todd.fujinaka@intel.com> Fixes: 12dcd86b75 ("igb: fix stats handling") (this added the spin_lock) Signed-off-by: Bernhard Kaindl <bk-linux@use.startmail.com> Tested-by: Aaron Brown <aaron.f.brown@intel.com> Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>		2014-10-02 02:30:39 -07:00
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e1000_82575.c	igb: add flags to set eee advertisement mode	2014-09-06 05:00:39 -07:00
e1000_82575.h	igb: add flags to set eee advertisement mode	2014-09-06 05:00:39 -07:00
e1000_defines.h	igb: Workaround for i210 Errata 25: Slow System Clock	2014-07-10 01:48:28 -07:00
e1000_hw.h	igb: remove blocking phy read from inside spinlock	2014-10-02 02:30:39 -07:00
e1000_i210.c	igb: Workaround for i210 Errata 25: Slow System Clock	2014-07-10 01:48:28 -07:00
e1000_i210.h	igb: Workaround for i210 Errata 25: Slow System Clock	2014-07-10 01:48:28 -07:00
e1000_mac.c	igb: Cleanups to fix msleep warnings	2014-04-24 17:41:15 -07:00
e1000_mac.h	igb: Cleanups to change comment style on license headers	2014-04-24 17:26:27 -07:00
e1000_mbx.c	igb: Cleanups to change comment style on license headers	2014-04-24 17:26:27 -07:00
e1000_mbx.h	igb: Cleanups to change comment style on license headers	2014-04-24 17:26:27 -07:00
e1000_nvm.c	igb/ixgbe: remove return statements for void functions	2014-05-23 05:28:41 -07:00
e1000_nvm.h	igb: Cleanups to change comment style on license headers	2014-04-24 17:26:27 -07:00
e1000_phy.c	igb: remove redundant PHY power down register write	2014-05-27 02:10:44 -07:00
e1000_phy.h	igb: remove redundant PHY power down register write	2014-05-27 02:10:44 -07:00
e1000_regs.h	igb: Add message when malformed packets detected by hw	2014-07-24 03:00:37 -07:00
igb_ethtool.c	igb: add flags to set eee advertisement mode	2014-09-06 05:00:39 -07:00
igb_hwmon.c	igb: Cleanups to change comment style on license headers	2014-04-24 17:26:27 -07:00
igb_main.c	igb: remove blocking phy read from inside spinlock	2014-10-02 02:30:39 -07:00
igb_ptp.c	igb: separate hardware setting from the set_ts_config ioctl	2014-06-11 08:45:55 -07:00
igb.h	igb: remove blocking phy read from inside spinlock	2014-10-02 02:30:39 -07:00
Makefile	igb: Update license text to remove FSF address and update copyright.	2014-02-26 15:54:52 -05:00