Commit Graph

71 Commits

Author SHA1 Message Date
Alexey Dobriyan a6b7a40786 net: remove interrupt.h inclusion from netdevice.h
* remove interrupt.g inclusion from netdevice.h -- not needed
* fixup fallout, add interrupt.h and hardirq.h back where needed.

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-06-06 22:55:11 -07:00
FUJITA Tomonori 1591cb6083 starfire: clean up dma_addr_t size test
Now we have CONFIG_ARCH_DMA_ADDR_T_64BIT. We can fix the hacky
dma_addr_t size test cleanly.

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-04-01 20:10:08 -07:00
Ben Hutchings f4d5900a99 starfire: Fix dma_addr_t size test for MIPS
Commit 56543af "starfire: use BUILD_BUG_ON for netdrv_addr_t" revealed
that the preprocessor condition used to find the size of dma_addr_t
yielded the wrong result for some architectures and configurations.
This was kluged for 64-bit PowerPC in commit 3e502e6 by adding yet
another case to the condition.  However, 64-bit MIPS configurations
are not detected reliably either.

This should be fixed by using CONFIG_ARCH_DMA_ADDR_T_64BIT, but that
isn't yet defined everywhere it should be.

Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
2010-12-31 12:33:17 -08:00
David S. Miller 3e502e6358 starfire: Temporary kludge to fix powerpc build.
Add a dma_addr_t 64-bit case for powerpc with 64-bit phys addresses.

Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2010-09-01 19:19:54 -07:00
Akinobu Mita 56543af956 starfire: use BUILD_BUG_ON for netdrv_addr_t
Detect size mismatch for netdrv_addr_t at build time rather than
checking at module load time.

Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Cc: Ion Badulescu <ionut@badula.org>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: netdev@vger.kernel.org
Signed-off-by: David S. Miller <davem@davemloft.net>
2010-08-28 15:37:05 -07:00
Akinobu Mita d08336e999 starfire: use PCI_VDEVICE
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Cc: Ion Badulescu <ionut@badula.org>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: netdev@vger.kernel.org
Signed-off-by: David S. Miller <davem@davemloft.net>
2010-08-28 15:37:05 -07:00
Kulikov Vasiliy 86678a2018 starfire: Use the instance of net_device_stats from net_device.
Since net_device has an instance of net_device_stats,
we can remove the instance of this from the adapter structure.

Signed-off-by: Kulikov Vasiliy <segooon@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2010-07-05 19:41:15 -07:00
Joe Perches a4b770972b drivers/net: Remove unnecessary returns from void function()s
This patch removes from drivers/net/ all the unnecessary
return; statements that precede the last closing brace of
void functions.

It does not remove the returns that are immediately
preceded by a label as gcc doesn't like that.

It also does not remove null void functions with return.

Done via:
$ grep -rP --include=*.[ch] -l "return;\n}" net/ | \
  xargs perl -i -e 'local $/ ; while (<>) { s/\n[ \t\n]+return;\n}/\n}/g; print; }'

with some cleanups by hand.

Compile tested x86 allmodconfig only.

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2010-05-14 00:19:28 -07:00
Eric Dumazet 1ae5dc342a net: trans_start cleanups
Now that core network takes care of trans_start updates, dont do it
in drivers themselves, if possible. Drivers can avoid one cache miss
(on dev->trans_start) in their start_xmit() handler.

Exceptions are NETIF_F_LLTX drivers

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2010-05-10 05:01:31 -07:00
Jiri Pirko 22bedad3ce net: convert multicast list to list_head
Converts the list and the core manipulating with it to be the same as uc_list.

+uses two functions for adding/removing mc address (normal and "global"
 variant) instead of a function parameter.
+removes dev_mcast.c completely.
+exposes netdev_hw_addr_list_* macros along with __hw_addr_* functions for
 manipulation with lists on a sandbox (used in bonding and 80211 drivers)

Signed-off-by: Jiri Pirko <jpirko@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2010-04-03 14:22:15 -07:00
Jiri Pirko 567ec874d1 net: convert multiple drivers to use netdev_for_each_mc_addr, part6
Signed-off-by: Jiri Pirko <jpirko@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2010-02-26 02:07:31 -08:00
Jiri Pirko 5508590c19 net: convert multiple drivers to use netdev_for_each_mc_addr, part2
Signed-off-by: Jiri Pirko <jpirko@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2010-02-18 14:47:49 -08:00
Jiri Pirko 4cd24eaf0c net: use netdev_mc_count and netdev_mc_empty when appropriate
This patch replaces dev->mc_count in all drivers (hopefully I didn't miss
anything). Used spatch and did small tweaks and conding style changes when
it was suitable.

Jirka

Signed-off-by: Jiri Pirko <jpirko@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2010-02-12 11:38:58 -08:00
David S. Miller 05ba712d7e Merge branch 'master' of master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6 2010-01-28 06:12:38 -08:00
Ben Hutchings c928febf4b starfire: clean up properly if firmware loading fails
netdev_open() will return without cleaning up net device or hardware state
if firmware loading fails.  This results in a BUG() on a second attempt to
bring the interface up, reported in
<http://bugzilla.kernel.org/show_bug.cgi?id=15091>, and probably has even
worse effects if the driver is removed afterwards.

Call netdev_close() to clean up on failure.

Addresses http://bugzilla.kernel.org/show_bug.cgi?id=15091

Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
Reported-by: Michael Moffatt <michael@moffatt.org.nz>
Tested-by: Michael Moffatt <michael@moffatt.org.nz>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2010-01-26 21:05:25 -08:00
Alexey Dobriyan a3aa18842a drivers/net/: use DEFINE_PCI_DEVICE_TABLE()
Use DEFINE_PCI_DEVICE_TABLE() so we get place PCI ids table into correct section
in every case.

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2010-01-07 23:54:26 -08:00
Joe Perches 8e95a2026f drivers/net: Move && and || to end of previous line
Only files where David Miller is the primary git-signer.
wireless, wimax, ixgbe, etc are not modified.

Compile tested x86 allyesconfig only
Not all files compiled (not x86 compatible)

Added a few > 80 column lines, which I ignored.
Existing checkpatch complaints ignored.

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-12-03 13:18:01 -08:00
Joe Perches a0607fd3a2 drivers/net: request_irq - Remove unnecessary leading & from second arg
Not as fancy as coccinelle.  Checkpatch errors ignored.
Compile tested allyesconfig x86, not all files compiled.

grep -rPl --include=*.[ch] "\brequest_irq\s*\([^,\)]+,\s*\&" drivers/net | while read file ; do \
	perl -i -e 'local $/; while (<>) { s@(\brequest_irq\s*\([^,\)]+,\s*)\&@\1@g ; print ; }' $file ;\
done

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-11-18 23:29:17 -08:00
Stephen Hemminger 61357325f3 netdev: convert bulk of drivers to netdev_tx_t
In a couple of cases collapse some extra code like:
   int retval = NETDEV_TX_OK;
   ...
   return retval;
into
   return NETDEV_TX_OK;

Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-09-01 01:14:07 -07:00
David S. Miller aa11d958d1 Merge branch 'master' of master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6
Conflicts:
	arch/microblaze/include/asm/socket.h
2009-08-12 17:44:53 -07:00
Joe Perches ad361c9884 Remove multiple KERN_ prefixes from printk formats
Commit 5fd29d6ccb ("printk: clean up
handling of log-levels and newlines") changed printk semantics.  printk
lines with multiple KERN_<level> prefixes are no longer emitted as
before the patch.

<level> is now included in the output on each additional use.

Remove all uses of multiple KERN_<level>s in formats.

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-07-08 10:30:03 -07:00
Patrick McHardy 6ed106549d net: use NETDEV_TX_OK instead of 0 in ndo_start_xmit() functions
This patch is the result of an automatic spatch transformation to convert
all ndo_start_xmit() return values of 0 to NETDEV_TX_OK.

Some occurences are missed by the automatic conversion, those will be
handled in a seperate patch.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-07-05 19:16:04 -07:00
Patrick McHardy 5b54814022 net: use symbolic values for ndo_start_xmit() return codes
Convert magic values 1 and -1 to NETDEV_TX_BUSY and NETDEV_TX_LOCKED respectively.

0 (NETDEV_TX_OK) is not changed to keep the noise down, except in very few cases
where its in direct proximity to one of the other values.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-06-13 01:18:50 -07:00
Stephen Hemminger b5defaa5d6 starfire: fix non-constant printk warnings
Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-02-26 22:22:00 -08:00
Ben Hutchings 288379f050 net: Remove redundant NAPI functions
Following the removal of the unused struct net_device * parameter from
the NAPI functions named *netif_rx_* in commit 908a7a1, they are
exactly equivalent to the corresponding *napi_* functions and are
therefore redundant.

Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-01-21 14:33:50 -08:00
Stephen Hemminger 4fc8006e00 starfire: update to net_device_ops
Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-01-07 17:58:17 -08:00
Jaswinder Singh Rajput cfc3a44c3c starfire: use request_firmware()
Firmware blob is big endian

Signed-off-by: Jaswinder Singh Rajput <jaswinderrajput@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-01-04 16:12:11 -08:00
Hannes Eder e4c3c13cb4 drivers/net: fix sparse warnings: make do-while a compound statement
While at it insert some extra curly braces and fix formatting.

Fix this sparse warnings:

  drivers/net/atp.c:811:8: warning: do-while statement is not a compound statement
  drivers/net/atp.c:813:8: warning: do-while statement is not a compound statement
  drivers/net/atp.c:815:11: warning: do-while statement is not a compound statement
  drivers/net/atp.c:817:11: warning: do-while statement is not a compound statement
  drivers/net/plip.c:642:4: warning: do-while statement is not a compound statement
  drivers/net/plip.c:647:4: warning: do-while statement is not a compound statement
  drivers/net/plip.c:820:4: warning: do-while statement is not a compound statement
  drivers/net/plip.c:825:4: warning: do-while statement is not a compound statement
  drivers/net/starfire.c:886:3: warning: do-while statement is not a compound statement

Signed-off-by: Hannes Eder <hannes@hanneseder.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-12-25 23:55:35 -08:00
David S. Miller 6332178d91 Merge branch 'master' of master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6
Conflicts:

	drivers/net/ppp_generic.c
2008-12-23 17:56:23 -08:00
Neil Horman 908a7a16b8 net: Remove unused netdev arg from some NAPI interfaces.
When the napi api was changed to separate its 1:1 binding to the net_device
struct, the netif_rx_[prep|schedule|complete] api failed to remove the now
vestigual net_device structure parameter.  This patch cleans up that api by
properly removing it..

Signed-off-by: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-12-22 20:43:12 -08:00
Jarek Poplawski 9a3de25544 drivers/net: starfire: Fix napi ->poll() weight handling
starfire napi ->poll() handler can return work == weight after calling
netif_rx_complete() (if there is no more work). It is illegal and this
patch fixes it.

Reported-by: Alexander Huemer <alexander.huemer@sbg.ac.at>
Tested-by: Alexander Huemer <alexander.huemer@sbg.ac.at>
Signed-off-by: Jarek Poplawski <jarkao2@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-12-16 15:42:20 -08:00
David S. Miller babcda74e9 drivers/net: Kill now superfluous ->last_rx stores.
The generic packet receive code takes care of setting
netdev->last_rx when necessary, for the sake of the
bonding ARP monitor.

Drivers need not do it any more.

Some cases had to be skipped over because the drivers
were making use of the ->last_rx value themselves.

Signed-off-by: David S. Miller <davem@davemloft.net>
2008-11-03 21:11:17 -08:00
Johannes Berg e174961ca1 net: convert print_mac to %pM
This converts pretty much everything to print_mac. There were
a few things that had conflicts which I have just dropped for
now, no harm done.

I've built an allyesconfig with this and looked at the files
that weren't built very carefully, but it's a huge patch.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-10-27 17:06:18 -07:00
Francois Romieu a6676019a7 starfire: delete non NAPI code from the driver.
Signed-off-by: Francois Romieu <romieu@fr.zoreil.com>
Acked-by: Jeff Garzik <jgarzik@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-07-07 22:40:42 -07:00
Patrick McHardy 38b221957b netdrv: don't truncate VLAN TCI with VLAN stripping
The vlan_hwaccel_{rx,receive_skb} functions expect the full TCI field
for priority mappings, don't truncate the upper 4 bits.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Acked-by: Jeff Garzik <jgarzik@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-07-06 20:48:41 -07:00
David S. Miller 21f644f3ea [NET]: Undo code bloat in hot paths due to print_mac().
If print_mac() is used inside of a pr_debug() the compiler
can't see that the call is redundant so still performs it
even of pr_debug() ends up being a nop.

So don't use print_mac() in such cases in hot code paths,
use MAC_FMT et al. instead.

As noted by Joe Perches, pr_debug() could be modified to
handle this better, but that is a change to an interface
used by the entire kernel and thus needs to be validated
carefully.  This here is thus the less risky fix for
2.6.25

Signed-off-by: David S. Miller <davem@davemloft.net>
2008-04-08 16:50:44 -07:00
Andrew Morton da219b7c69 starfire: secton fix
gcc-3.4.4 on powerpc:

drivers/net/starfire.c:219: error: version causes a section type conflict

Cc: Jeff Garzik <jeff@garzik.org>
Cc: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-02-09 23:42:17 -08:00
Al Viro 813820b9b9 starfire VLAN fix
Recognized VLAN ids are set via writew(), should go in host-endian.
That's a long-standing bug, BTW - see http://lkml.org/lkml/2004/2/27/180
for example.  What happens is that card gets VLAN id table populated by
byteswapped values on little-endian boxen (so 257 works as expected, 256
and 258 do not, etc.).  Bug is easily reproduced, patch fixes it.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
2007-12-14 15:26:04 -05:00
Al Viro 88b1943bd3 starfire: trivial endianness annotations
Note: we still have several fishy areas - mcast filter
and vlan handling.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
2007-10-10 16:52:02 -07:00
Joe Perches 0795af5729 [NET]: Introduce and use print_mac() and DECLARE_MAC_BUF()
This is nicer than the MAC_FMT stuff.

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-10 16:51:42 -07:00
Ralf Baechle 10d024c1b2 [NET]: Nuke SET_MODULE_OWNER macro.
It's been a useless no-op for long enough in 2.6 so I figured it's time to
remove it.  The number of people that could object because they're
maintaining unified 2.4 and 2.6 drivers is probably rather small.

[ Handled drivers added by netdev tree and some missed IRDA cases... -DaveM ]

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-10 16:51:13 -07:00
Stephen Hemminger bea3348eef [NET]: Make NAPI polling independent of struct net_device objects.
Several devices have multiple independant RX queues per net
device, and some have a single interrupt doorbell for several
queues.

In either case, it's easier to support layouts like that if the
structure representing the poll is independant from the net
device itself.

The signature of the ->poll() call back goes from:

	int foo_poll(struct net_device *dev, int *budget)

to

	int foo_poll(struct napi_struct *napi, int budget)

The caller is returned the number of RX packets processed (or
the number of "NAPI credits" consumed if you want to get
abstract).  The callee no longer messes around bumping
dev->quota, *budget, etc. because that is all handled in the
caller upon return.

The napi_struct is to be embedded in the device driver private data
structures.

Furthermore, it is the driver's responsibility to disable all NAPI
instances in it's ->stop() device close handler.  Since the
napi_struct is privatized into the driver's private data structures,
only the driver knows how to get at all of the napi_struct instances
it may have per-device.

With lots of help and suggestions from Rusty Russell, Roland Dreier,
Michael Chan, Jeff Garzik, and Jamal Hadi Salim.

Bug fixes from Thomas Graf, Roland Dreier, Peter Zijlstra,
Joseph Fannin, Scott Wood, Hans J. Koch, and Michael Chan.

[ Ported to current tree and all drivers converted.  Integrated
  Stephen's follow-on kerneldoc additions, and restored poll_list
  handling to the old style to fix mutual exclusion issues.  -DaveM ]

Signed-off-by: Stephen Hemminger <shemminger@linux-foundation.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-10 16:47:45 -07:00
Linus Torvalds 21ba0f88ae Merge master.kernel.org:/pub/scm/linux/kernel/git/gregkh/pci-2.6
* master.kernel.org:/pub/scm/linux/kernel/git/gregkh/pci-2.6: (34 commits)
  PCI: Only build PCI syscalls on architectures that want them
  PCI: limit pci_get_bus_and_slot to domain 0
  PCI: hotplug: acpiphp: avoid acpiphp "cannot get bridge info" PCI hotplug failure
  PCI: hotplug: acpiphp: remove hot plug parameter write to PCI host bridge
  PCI: hotplug: acpiphp: fix slot poweroff problem on systems without _PS3
  PCI: hotplug: pciehp: wait for 1 second after power off slot
  PCI: pci_set_power_state(): check for PM capabilities earlier
  PCI: cpci_hotplug: Convert to use the kthread API
  PCI: add pci_try_set_mwi
  PCI: pcie: remove SPIN_LOCK_UNLOCKED
  PCI: ROUND_UP macro cleanup in drivers/pci
  PCI: remove pci_dac_dma_... APIs
  PCI: pci-x-pci-express-read-control-interfaces cleanups
  PCI: Fix typo in include/linux/pci.h
  PCI: pci_ids, remove double or more empty lines
  PCI: pci_ids, add atheros and 3com_2 vendors
  PCI: pci_ids, reorder some entries
  PCI: i386: traps, change VENDOR to DEVICE
  PCI: ATM: lanai, change VENDOR to DEVICE
  PCI: Change all drivers to use pci_device->revision
  ...
2007-07-12 13:40:57 -07:00
Randy Dunlap 694625c0b3 PCI: add pci_try_set_mwi
As suggested by Andrew, add pci_try_set_mwi(), which does not require
return-value checking.

- add pci_try_set_mwi() without __must_check
- make it return 0 on success, errno if the "try" failed or error
- review callers

Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-07-11 16:02:11 -07:00
David S. Miller 8c7b7faaa6 [NET]: Kill eth_copy_and_sum().
It hasn't "summed" anything in over 7 years, and it's
just a straight mempcy ala skb_copy_to_linear_data()
so just get rid of it.

Signed-off-by: David S. Miller <davem@davemloft.net>
2007-07-10 22:08:12 -07:00
maximilian attems 983b7dc07f starfire list alpha as 64 bit arch
instead of:
"This driver has not been ported to this 64-bit architecture yet."
the driver is said to work on alpha, see
http://bugs.debian.org/305330

Signed-off-by: maximilian attems <max@stro.at>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
2007-07-02 08:24:51 -04:00
Arnaldo Carvalho de Melo 4c13eb6657 [ETH]: Make eth_type_trans set skb->dev like the other *_type_trans
One less thing for drivers writers to worry about.

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-25 22:24:30 -07:00
Dan Aloni 5c15bdec5c [VLAN]: Avoid a 4-order allocation.
This patch splits the vlan_group struct into a multi-allocated struct. On
x86_64, the size of the original struct is a little more than 32KB, causing
a 4-order allocation, which is prune to problems caused by buddy-system
external fragmentation conditions.

I couldn't just use vmalloc() because vfree() cannot be called in the
softirq context of the RCU callback.

Signed-off-by: Dan Aloni <da-x@monatomic.org>
Acked-by: Jeff Garzik <jeff@garzik.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-03-02 20:44:51 -08:00
Al Viro d7fe0f241d [PATCH] severing skbuff.h -> mm.h
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2006-12-04 02:00:34 -05:00
David Howells 7d12e780e0 IRQ: Maintain regs pointer globally rather than passing to IRQ handlers
Maintain a per-CPU global "struct pt_regs *" variable which can be used instead
of passing regs around manually through all ~1800 interrupt handlers in the
Linux kernel.

The regs pointer is used in few places, but it potentially costs both stack
space and code to pass it around.  On the FRV arch, removing the regs parameter
from all the genirq function results in a 20% speed up of the IRQ exit path
(ie: from leaving timer_interrupt() to leaving do_IRQ()).

Where appropriate, an arch may override the generic storage facility and do
something different with the variable.  On FRV, for instance, the address is
maintained in GR28 at all times inside the kernel as part of general exception
handling.

Having looked over the code, it appears that the parameter may be handed down
through up to twenty or so layers of functions.  Consider a USB character
device attached to a USB hub, attached to a USB controller that posts its
interrupts through a cascaded auxiliary interrupt controller.  A character
device driver may want to pass regs to the sysrq handler through the input
layer which adds another few layers of parameter passing.

I've build this code with allyesconfig for x86_64 and i386.  I've runtested the
main part of the code on FRV and i386, though I can't test most of the drivers.
I've also done partial conversion for powerpc and MIPS - these at least compile
with minimal configurations.

This will affect all archs.  Mostly the changes should be relatively easy.
Take do_IRQ(), store the regs pointer at the beginning, saving the old one:

	struct pt_regs *old_regs = set_irq_regs(regs);

And put the old one back at the end:

	set_irq_regs(old_regs);

Don't pass regs through to generic_handle_irq() or __do_IRQ().

In timer_interrupt(), this sort of change will be necessary:

	-	update_process_times(user_mode(regs));
	-	profile_tick(CPU_PROFILING, regs);
	+	update_process_times(user_mode(get_irq_regs()));
	+	profile_tick(CPU_PROFILING);

I'd like to move update_process_times()'s use of get_irq_regs() into itself,
except that i386, alone of the archs, uses something other than user_mode().

Some notes on the interrupt handling in the drivers:

 (*) input_dev() is now gone entirely.  The regs pointer is no longer stored in
     the input_dev struct.

 (*) finish_unlinks() in drivers/usb/host/ohci-q.c needs checking.  It does
     something different depending on whether it's been supplied with a regs
     pointer or not.

 (*) Various IRQ handler function pointers have been moved to type
     irq_handler_t.

Signed-Off-By: David Howells <dhowells@redhat.com>
(cherry picked from 1b16e7ac850969f38b375e511e3fa2f474a33867 commit)
2006-10-05 15:10:12 +01:00