Return-path: Received: from charlotte.tuxdriver.com ([70.61.120.58]:37235 "EHLO smtp.tuxdriver.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751911Ab1CDNpn (ORCPT ); Fri, 4 Mar 2011 08:45:43 -0500 Date: Fri, 4 Mar 2011 08:37:23 -0500 From: "John W. Linville" To: Mohammed Shafi Cc: Mohammed Shajakhan , "linux-wireless@vger.kernel.org" , Luis Rodriguez , stable@kernel.org Subject: Re: [RFC] ath9k: Fix ath9k prevents CPU to enter C3 states Message-ID: <20110304133722.GA9866@tuxdriver.com> References: <1297785572-27955-1-git-send-email-mshajakhan@atheros.com> <20110215161222.GD2557@tuxdriver.com> <4D5B5B02.4020101@atheros.com> <4D70816D.80304@atheros.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii In-Reply-To: <4D70816D.80304@atheros.com> Sender: linux-wireless-owner@vger.kernel.org List-ID: On Fri, Mar 04, 2011 at 11:36:37AM +0530, Mohammed Shafi wrote: > On Wednesday 16 February 2011 10:35 AM, Mohammed Shafi wrote: > >On Tuesday 15 February 2011 09:42 PM, John W. Linville wrote: > >>Despite the [RFC], I am applying this. I should have reverted all > >>of this three weeks ago... > John can you please push this to stable kernel ? Stable folks, this is the commit in Linus's tree; commit 0f5cd45960173ba5b36727decbb4a241cbd35ef9 Author: Mohammed Shafi Shajakhan Date: Tue Feb 15 21:29:32 2011 +0530 ath9k: Fix ath9k prevents CPU to enter C3 states The DMA latency issue is observed only in Intel pinetrail platforms but in the driver we had a default PM-QOS value of 55. This caused unnecessary power consumption and battery drain in other platforms. Remove the pm-qos thing in the driver code and address the throughput issue in Intel pinetrail platfroms in user space using any one of the scripts in below links: http://www.kernel.org/pub/linux/kernel/people/mcgrof/scripts/cpudmalatency.c http://johannes.sipsolutions.net/files/netlatency.c.txt More details can be found in the following bugzilla link: https://bugzilla.kernel.org/show_bug.cgi?id=27532 This reverts the following commits: 98c316e348bedffa730e6f1e4baeb8a3c3e0f28b 4dc3530df7c0428b41c00399a7ee8c929406d181 10598c124ecabbbfd7522f74de19b8f7d52a1bee Signed-off-by: Mohammed Shafi Shajakhan Signed-off-by: John W. Linville > >Thanks John. > >>John > >> > >>On Tue, Feb 15, 2011 at 09:29:32PM +0530, Mohammed Shafi > >>Shajakhan wrote: > >>>From: Mohammed Shafi Shajakhan > >>> > >>>The DMA latency issue is observed only in Intel pinetrail platforms but > >>>in the driver we had a default PM-QOS value of 55. This caused > >>>unnecessary power consumption and battery drain in other platforms. > >>> Remove the pm-qos thing in the driver code and address the > >>>throughput issue in > >>>Intel pinetrail platfroms in user space using any one of the > >>>scripts in below links: > >>>http://www.kernel.org/pub/linux/kernel/people/mcgrof/scripts/cpudmalatency.c > >>> > >>>http://johannes.sipsolutions.net/files/netlatency.c.txt > >>>More details can be found in the following bugzilla link: > >>>https://bugzilla.kernel.org/show_bug.cgi?id=27532 > >>> > >>>Signed-off-by: Mohammed Shafi Shajakhan > >>>--- > >>> drivers/net/wireless/ath/ath9k/ath9k.h | 5 ----- > >>> drivers/net/wireless/ath/ath9k/init.c | 7 ------- > >>> drivers/net/wireless/ath/ath9k/main.c | 8 -------- > >>> 3 files changed, 0 insertions(+), 20 deletions(-) > >>> > >>>diff --git a/drivers/net/wireless/ath/ath9k/ath9k.h > >>>b/drivers/net/wireless/ath/ath9k/ath9k.h > >>>index ba436cd..0052f64 100644 > >>>--- a/drivers/net/wireless/ath/ath9k/ath9k.h > >>>+++ b/drivers/net/wireless/ath/ath9k/ath9k.h > >>>@@ -21,7 +21,6 @@ > >>> #include > >>> #include > >>> #include > >>>-#include > >>> > >>> #include "debug.h" > >>> #include "common.h" > >>>@@ -57,8 +56,6 @@ struct ath_node; > >>> > >>> #define A_MAX(a, b) ((a)> (b) ? (a) : (b)) > >>> > >>>-#define ATH9K_PM_QOS_DEFAULT_VALUE 55 > >>>- > >>> #define TSF_TO_TU(_h,_l) \ > >>> ((((u32)(_h))<< 22) | (((u32)(_l))>> 10)) > >>> > >>>@@ -650,7 +647,6 @@ struct ath_softc { > >>> > >>> struct ath_ant_comb ant_comb; > >>> > >>>- struct pm_qos_request_list pm_qos_req; > >>> }; > >>> > >>> void ath9k_tasklet(unsigned long data); > >>>@@ -665,7 +661,6 @@ static inline void > >>>ath_read_cachesize(struct ath_common *common, int *csz) > >>> extern struct ieee80211_ops ath9k_ops; > >>> extern int ath9k_modparam_nohwcrypt; > >>> extern int led_blink; > >>>-extern int ath9k_pm_qos_value; > >>> extern bool is_ath9k_unloaded; > >>> > >>> irqreturn_t ath_isr(int irq, void *dev); > >>>diff --git a/drivers/net/wireless/ath/ath9k/init.c > >>>b/drivers/net/wireless/ath/ath9k/init.c > >>>index e5c1eea..8fed4e4 100644 > >>>--- a/drivers/net/wireless/ath/ath9k/init.c > >>>+++ b/drivers/net/wireless/ath/ath9k/init.c > >>>@@ -41,9 +41,6 @@ static int ath9k_btcoex_enable; > >>> module_param_named(btcoex_enable, ath9k_btcoex_enable, int, 0444); > >>> MODULE_PARM_DESC(btcoex_enable, "Enable wifi-BT coexistence"); > >>> > >>>-int ath9k_pm_qos_value = ATH9K_PM_QOS_DEFAULT_VALUE; > >>>-module_param_named(pmqos, ath9k_pm_qos_value, int, S_IRUSR | > >>>S_IRGRP | S_IROTH); > >>>-MODULE_PARM_DESC(pmqos, "User specified PM-QOS value"); > >>> > >>> bool is_ath9k_unloaded; > >>> /* We use the hw_value as an index into our private channel > >>>structure */ > >>>@@ -760,9 +757,6 @@ int ath9k_init_device(u16 devid, struct > >>>ath_softc *sc, u16 subsysid, > >>> ath_init_leds(sc); > >>> ath_start_rfkill_poll(sc); > >>> > >>>- pm_qos_add_request(&sc->pm_qos_req, PM_QOS_CPU_DMA_LATENCY, > >>>- PM_QOS_DEFAULT_VALUE); > >>>- > >>> return 0; > >>> > >>> error_world: > >>>@@ -819,7 +813,6 @@ void ath9k_deinit_device(struct ath_softc *sc) > >>> ath9k_ps_restore(sc); > >>> > >>> ieee80211_unregister_hw(hw); > >>>- pm_qos_remove_request(&sc->pm_qos_req); > >>> ath_rx_cleanup(sc); > >>> ath_tx_cleanup(sc); > >>> ath9k_deinit_softc(sc); > >>>diff --git a/drivers/net/wireless/ath/ath9k/main.c > >>>b/drivers/net/wireless/ath/ath9k/main.c > >>>index 4f568b8..1d2c7c3 100644 > >>>--- a/drivers/net/wireless/ath/ath9k/main.c > >>>+++ b/drivers/net/wireless/ath/ath9k/main.c > >>>@@ -1117,12 +1117,6 @@ static int ath9k_start(struct ieee80211_hw *hw) > >>> ath9k_btcoex_timer_resume(sc); > >>> } > >>> > >>>- /* User has the option to provide pm-qos value as a module > >>>- * parameter rather than using the default value of > >>>- * 'ATH9K_PM_QOS_DEFAULT_VALUE'. > >>>- */ > >>>- pm_qos_update_request(&sc->pm_qos_req, ath9k_pm_qos_value); > >>>- > >>> if (ah->caps.pcie_lcr_extsync_en&& > >>>common->bus_ops->extn_synch_en) > >>> common->bus_ops->extn_synch_en(common); > >>> > >>>@@ -1267,8 +1261,6 @@ static void ath9k_stop(struct ieee80211_hw *hw) > >>> > >>> sc->sc_flags |= SC_OP_INVALID; > >>> > >>>- pm_qos_update_request(&sc->pm_qos_req, PM_QOS_DEFAULT_VALUE); > >>>- > >>> mutex_unlock(&sc->mutex); > >>> > >>> ath_dbg(common, ATH_DBG_CONFIG, "Driver halt\n"); > >>>-- > >>>1.7.0.4 > >>> > >>> > -- > To unsubscribe from this list: send the line "unsubscribe linux-wireless" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html > -- John W. Linville Someday the world will need a hero, and you linville@tuxdriver.com might be all we have. Be ready.