e100: expose broadcast_disabled as a module option
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From: Jeff Kirsher on 23 Apr 2010 16:30 On Fri, Apr 23, 2010 at 13:14, Erwan Velu <erwanaliasr1(a)gmail.com> wrote: > Hi folks, > > I've been facing a very noisy network where hundreds broadcast packets > were generated every second. > When this traffic can't be controlled at the source, there is a side > effect on some systems. > I was having some idle systems that will never be targeted by this > broadcast traffic that got loaded just by receiving that "flood". > I mean by loaded that this light hardware was generating 300 > context/switches per second. > > I was looking for many options to avoid this traffic to disturb this > hosts and I discovered that the e100 driver was featuring a > "broadcast_disabled" configure option. > I realize that this option is not controllable, so I wrote this simple > patch that expose this option as a module option. > This allow me to tell this hosts not to listen anymore this traffic. > > The result is clearly good as my systems are now running at 21 > context/switches while being idle. > Hope this patch isn't too bad and could help others that faces the same problem. > > Patch can be downloaded here : > http://konilope.linuxeries.org/e100_broadcast_disabled.patch > > Even if gmail is eating the inlined, patch, at least that make it > easier to read it for humans. > If the patch is acked, the downloaded one will be more clean ;) > > This patch was generated on top of the latest 2.6 torvald's git. > Cheers, > Erwan > > Signed-off-by: Erwan Velu <erwanaliasr1(a)gmail.com> > > diff --git a/drivers/net/e100.c b/drivers/net/e100.c > index b997e57..2ba582f 100644 > --- a/drivers/net/e100.c > +++ b/drivers/net/e100.c > @@ -194,12 +194,15 @@ MODULE_FIRMWARE(FIRMWARE_D102E); > static int debug = 3; > static int eeprom_bad_csum_allow = 0; > static int use_io = 0; > +static int broadcast_disabled = 0; > module_param(debug, int, 0); > module_param(eeprom_bad_csum_allow, int, 0); > module_param(use_io, int, 0); > +module_param(broadcast_disabled, int, 0); > MODULE_PARM_DESC(debug, "Debug level (0=none,...,16=all)"); > MODULE_PARM_DESC(eeprom_bad_csum_allow, "Allow bad eeprom checksums"); > MODULE_PARM_DESC(use_io, "Force use of i/o access mode"); > +MODULE_PARM_DESC(broadcast_disabled, "Filter broadcast packets > (0=disabled (default), 1=enabled)"); > #define DPRINTK(nlevel, klevel, fmt, args...) \ > (void)((NETIF_MSG_##nlevel & nic->msg_enable) && \ > printk(KERN_##klevel PFX "%s: %s: " fmt, nic->netdev->name, \ > @@ -1131,6 +1134,8 @@ static void e100_configure(struct nic *nic, > struct cb *cb, struct sk_buff *skb) > config->promiscuous_mode = 0x1; /* 1=on, 0=off */ > } > > + config->broadcast_disabled = broadcast_disabled; /* Broadcast filtering */ > + > if (nic->flags & multicast_all) > config->multicast_all = 0x1; /* 1=accept, 0=no */ > -- Adding Netdev... -- Cheers, Jeff -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo(a)vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
From: Stephen Hemminger on 23 Apr 2010 17:00 On Fri, 23 Apr 2010 13:22:22 -0700 Jeff Kirsher <jeffrey.t.kirsher(a)intel.com> wrote: > On Fri, Apr 23, 2010 at 13:14, Erwan Velu <erwanaliasr1(a)gmail.com> wrote: > > Hi folks, > > > > I've been facing a very noisy network where hundreds broadcast packets > > were generated every second. > > When this traffic can't be controlled at the source, there is a side > > effect on some systems. > > I was having some idle systems that will never be targeted by this > > broadcast traffic that got loaded just by receiving that "flood". > > I mean by loaded that this light hardware was generating 300 > > context/switches per second. > > > > I was looking for many options to avoid this traffic to disturb this > > hosts and I discovered that the e100 driver was featuring a > > "broadcast_disabled" configure option. > > I realize that this option is not controllable, so I wrote this simple > > patch that expose this option as a module option. > > This allow me to tell this hosts not to listen anymore this traffic. > > > > The result is clearly good as my systems are now running at 21 > > context/switches while being idle. > > Hope this patch isn't too bad and could help others that faces the same problem. > > > > Patch can be downloaded here : > > http://konilope.linuxeries.org/e100_broadcast_disabled.patch > > > > Even if gmail is eating the inlined, patch, at least that make it > > easier to read it for humans. > > If the patch is acked, the downloaded one will be more clean ;) > > > > This patch was generated on top of the latest 2.6 torvald's git. > > Cheers, > > Erwan > > > > Signed-off-by: Erwan Velu <erwanaliasr1(a)gmail.com> > > > > diff --git a/drivers/net/e100.c b/drivers/net/e100.c > > index b997e57..2ba582f 100644 > > --- a/drivers/net/e100.c > > +++ b/drivers/net/e100.c > > @@ -194,12 +194,15 @@ MODULE_FIRMWARE(FIRMWARE_D102E); > > static int debug = 3; > > static int eeprom_bad_csum_allow = 0; > > static int use_io = 0; > > +static int broadcast_disabled = 0; > > module_param(debug, int, 0); > > module_param(eeprom_bad_csum_allow, int, 0); > > module_param(use_io, int, 0); > > +module_param(broadcast_disabled, int, 0); > > MODULE_PARM_DESC(debug, "Debug level (0=none,...,16=all)"); > > MODULE_PARM_DESC(eeprom_bad_csum_allow, "Allow bad eeprom checksums"); > > MODULE_PARM_DESC(use_io, "Force use of i/o access mode"); > > +MODULE_PARM_DESC(broadcast_disabled, "Filter broadcast packets > > (0=disabled (default), 1=enabled)"); > > #define DPRINTK(nlevel, klevel, fmt, args...) \ > > (void)((NETIF_MSG_##nlevel & nic->msg_enable) && \ > > printk(KERN_##klevel PFX "%s: %s: " fmt, nic->netdev->name, \ > > @@ -1131,6 +1134,8 @@ static void e100_configure(struct nic *nic, > > struct cb *cb, struct sk_buff *skb) > > config->promiscuous_mode = 0x1; /* 1=on, 0=off */ > > } > > > > + config->broadcast_disabled = broadcast_disabled; /* Broadcast filtering */ > > + > > if (nic->flags & multicast_all) > > config->multicast_all = 0x1; /* 1=accept, 0=no */ > > -- > > Adding Netdev... > What is wrong with using existing IFF_BROADCAST flag? -- -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo(a)vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
From: Erwan Velu on 23 Apr 2010 17:10 I first tried "ifconfig -broadcast" without any success, so I forced the driver to unset IFF_BROADCAST, the interface didn't showed anymore the BROADCAST option with ifconfig. But I didn't noticed any reduction in the amount of context/switches on my host. I found the broadcast_disabled far more efficient when considering the cpu impact. 2010/4/23 Stephen Hemminger <shemminger(a)vyatta.com>: > On Fri, 23 Apr 2010 13:22:22 -0700 > Jeff Kirsher <jeffrey.t.kirsher(a)intel.com> wrote: > >> On Fri, Apr 23, 2010 at 13:14, Erwan Velu <erwanaliasr1(a)gmail.com> wrote: >> > Hi folks, >> > >> > I've been facing a very noisy network where hundreds broadcast packets >> > were generated every second. >> > When this traffic can't be controlled at the source, there is a side >> > effect on some systems. >> > I was having some idle systems that will never be targeted by this >> > broadcast traffic that got loaded just by receiving that "flood". >> > I mean by loaded that this light hardware was generating 300 >> > context/switches per second. >> > >> > I was looking for many options to avoid this traffic to disturb this >> > hosts and I discovered that the e100 driver was featuring a >> > "broadcast_disabled" configure option. >> > I realize that this option is not controllable, so I wrote this simple >> > patch that expose this option as a module option. >> > This allow me to tell this hosts not to listen anymore this traffic. >> > >> > The result is clearly good as my systems are now running at 21 >> > context/switches while being idle. >> > Hope this patch isn't too bad and could help others that faces the same problem. >> > >> > Patch can be downloaded here : >> > http://konilope.linuxeries.org/e100_broadcast_disabled.patch >> > >> > Even if gmail is eating the inlined, patch, at least that make it >> > easier to read it for humans. >> > If the patch is acked, the downloaded one will be more clean ;) >> > >> > This patch was generated on top of the latest 2.6 torvald's git. >> > Cheers, >> > Erwan >> > >> > Signed-off-by: Erwan Velu <erwanaliasr1(a)gmail.com> >> > >> > diff --git a/drivers/net/e100.c b/drivers/net/e100.c >> > index b997e57..2ba582f 100644 >> > --- a/drivers/net/e100.c >> > +++ b/drivers/net/e100.c >> > @@ -194,12 +194,15 @@ MODULE_FIRMWARE(FIRMWARE_D102E); >> > �static int debug = 3; >> > �static int eeprom_bad_csum_allow = 0; >> > �static int use_io = 0; >> > +static int broadcast_disabled = 0; >> > �module_param(debug, int, 0); >> > �module_param(eeprom_bad_csum_allow, int, 0); >> > �module_param(use_io, int, 0); >> > +module_param(broadcast_disabled, int, 0); >> > �MODULE_PARM_DESC(debug, "Debug level (0=none,...,16=all)"); >> > �MODULE_PARM_DESC(eeprom_bad_csum_allow, "Allow bad eeprom checksums"); >> > �MODULE_PARM_DESC(use_io, "Force use of i/o access mode"); >> > +MODULE_PARM_DESC(broadcast_disabled, "Filter broadcast packets >> > (0=disabled (default), 1=enabled)"); >> > �#define DPRINTK(nlevel, klevel, fmt, args...) \ >> > � � � �(void)((NETIF_MSG_##nlevel & nic->msg_enable) && \ >> > � � � �printk(KERN_##klevel PFX "%s: %s: " fmt, nic->netdev->name, \ >> > @@ -1131,6 +1134,8 @@ static void e100_configure(struct nic *nic, >> > struct cb *cb, struct sk_buff *skb) >> > � � � � � � � �config->promiscuous_mode = 0x1; � � � � /* 1=on, 0=off */ >> > � � � �} >> > >> > + � � � config->broadcast_disabled = broadcast_disabled; /* Broadcast filtering */ >> > + >> > � � � �if (nic->flags & multicast_all) >> > � � � � � � � �config->multicast_all = 0x1; � � � � � �/* 1=accept, 0=no */ >> > -- >> >> Adding Netdev... >> > > What is wrong with using existing IFF_BROADCAST flag? > > > -- > -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo(a)vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
From: Stephen Hemminger on 23 Apr 2010 18:10 On Fri, 23 Apr 2010 23:03:59 +0200 Erwan Velu <erwanaliasr1(a)gmail.com> wrote: > I first tried "ifconfig -broadcast" without any success, so I forced > the driver to unset IFF_BROADCAST, the interface didn't showed anymore > the BROADCAST option with ifconfig. But I didn't noticed any reduction > in the amount of context/switches on my host. > > I found the broadcast_disabled far more efficient when considering the > cpu impact. The point is that the driver can look at IFF_BROADCAST rather than having module parameter. Module parameters are device driver specific and should be avoid as much as possible in favor of general mechanism. This is a repeated problem where users and vendors make special hooks that only work with their driver, which makes life hard for other users and distribution providers. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo(a)vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
From: Erwan Velu on 26 Apr 2010 05:00
Agreed that will be a better implementation. Changes of IFF_BROADCAST could play with this "broadcast_disabled" configuration switch to increase the cpu efficiency. I'm not a kernel expert and I don't really figure how the changes of the IFF_BROADCAST should be forwarded to the interfaces and how it can be manipulated. I saw that ifconfig have a '-broadcast' option but looks like none of my drivers are compatible with that. Does any one you could help me understanding what should be the good way to 1- enabled/disabled IFF_BROADCAST for a given interface 2- populate this changes to the driver Once I'll be able to have a proper patch using that, I'll post it again to the list. Cheers, Erwan 2010/4/24 Stephen Hemminger <shemminger(a)vyatta.com>: > On Fri, 23 Apr 2010 23:03:59 +0200 [...] > The point is that the driver can look at IFF_BROADCAST rather than having > module parameter. Module parameters are device driver specific and should > be avoid as much as possible in favor of general mechanism. This is a repeated > problem where users and vendors make special hooks that only work with their > driver, which makes life hard for other users and distribution providers. > -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo(a)vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/ |