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)
* 'upstream-linus' of master.kernel.org:/pub/scm/linux/kernel/git/jgarzik/netdev-2.6: (217 commits)
net/ieee80211: fix more crypto-related build breakage
[PATCH] Spidernet: add ethtool -S (show statistics)
[NET] GT96100: Delete bitrotting ethernet driver
[PATCH] mv643xx_eth: restrict to 32-bit PPC_MULTIPLATFORM
[PATCH] Cirrus Logic ep93xx ethernet driver
r8169: the MMIO region of the 8167 stands behin BAR#1
e1000, ixgb: Remove pointless wrappers
[PATCH] Remove powerpc specific parts of 3c509 driver
[PATCH] s2io: Switch to pci_get_device
[PATCH] gt96100: move to pci_get_device API
[PATCH] ehea: bugfix for register access functions
[PATCH] e1000 disable device on PCI error
drivers/net/phy/fixed: #if 0 some incomplete code
drivers/net: const-ify ethtool_ops declarations
[PATCH] ethtool: allow const ethtool_ops
[PATCH] sky2: big endian
[PATCH] sky2: fiber support
[PATCH] sky2: tx pause bug fix
drivers/net: Trim trailing whitespace
[PATCH] ehea: IBM eHEA Ethernet Device Driver
...
Manually resolved conflicts in drivers/net/ixgb/ixgb_main.c and
drivers/net/sky2.c related to CHECKSUM_HW/CHECKSUM_PARTIAL changes by
commit 84fa7933a3 that just happened to be
next to unrelated changes in this update.
Replace CHECKSUM_HW by CHECKSUM_PARTIAL (for outgoing packets, whose
checksum still needs to be completed) and CHECKSUM_COMPLETE (for
incoming packets, device supplied full checksum).
Patch originally from Herbert Xu, updated by myself for 2.6.18-rc3.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
From: Michal Piotrowski <michal.k.k.piotrowski@gmail.com>
Signed-off-by: Michal Piotrowski <michal.k.k.piotrowski@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
This patch adds the wrapper function skb_is_gso which can be used instead
of directly testing skb_shinfo(skb)->gso_size. This makes things a little
nicer and allows us to change the primary key for indicating whether an skb
is GSO (if we ever want to do that).
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
Having separate fields in sk_buff for TSO/UFO (tso_size/ufo_size) is not
going to scale if we add any more segmentation methods (e.g., DCCP). So
let's merge them.
They were used to tell the protocol of a packet. This function has been
subsumed by the new gso_type field. This is essentially a set of netdev
feature bits (shifted by 16 bits) that are required to process a specific
skb. As such it's easy to tell whether a given device can process a GSO
skb: you just have to and the gso_type field and the netdev's features
field.
I've made gso_type a conjunction. The idea is that you have a base type
(e.g., SKB_GSO_TCPV4) that can be modified further to support new features.
For example, if we add a hardware TSO type that supports ECN, they would
declare NETIF_F_TSO | NETIF_F_TSO_ECN. All TSO packets with CWR set would
have a gso_type of SKB_GSO_TCPV4 | SKB_GSO_TCPV4_ECN while all other TSO
packets would be SKB_GSO_TCPV4. This means that only the CWR packets need
to be emulated in software.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
This fixes some uneeded rebuilds under drivers/net/chelsio after moving
the source tree. The makefiles used $(TOPDIR) for include paths, which
is unnecessary. Changed to use relative paths.
Compile tested, produces byte-identical code to the previous makefiles.
Signed-off-by: Carl-Daniel Hailfinger <c-d.hailfinger.devel.2006@gmx.net>
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
this changes if() BUG(); constructs to BUG_ON() which is
cleaner, contains unlikely() and can better optimized away.
Signed-off-by: Eric Sesterhenn <snakebyte@gmx.de>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
MODULE_PARM was actually breaking: recent gcc version optimize them out as
unused. It's time to replace the last users, which are generally in the
most unloved drivers anyway.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Adrian Bunk wrote:
> The Coverity checker spotted the following two array overflows in
> drivers/net/chelsio/sge.c (in both cases, the arrays contain 3
> elements):
[snip]
This is a bug. The array should contain 2 elements. Here is the fix.
Signed-off-by: Scott Bardone <sbardone@chelsio.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
The Coverity checker spotted these two unused variables.
Please check whether this patch is correct or whether they should be
used.
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
memset() is called before check.
Signed-off-by: Eric Sesterhenn <snakebyte@gmx.de>
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
The Chelsio driver does not return the correct values from
the transmit routine. It works because the values don't conflict,
but it is using the wrong defines. And -ENOMEM is not a legal return
value.
Since t1_sge_tx is only called in one place, making it static
allows compiler to be potentially inline it.
Signed-off-by: Stephen Hemminger <shemminger@osdl.org>
Signed-off-by: Jeff Garzik <jgarzik@pobox.com>
NULL noise removal, __iomem annotations, use of if_mii() instead of
open-coding it.
Signed-off-by: Al Viro <viro@parcelfarce.linux.theplanet.co.uk>
Signed-off-by: Jeff Garzik <jgarzik@pobox.com>
- Use extern prefix for functions required.
- Removed a lot of wrappers, including t1_read/write_reg_4.
- Removed various macros, using native kernel calls now.
- Enumerated various #defines.
- Removed a lot of shared code which is not currently used in "NIC only" mode.
- Removed dead code.
Documentation/networking/cxgb.txt:
- Updated release notes for version 2.1.1
drivers/net/chelsio/ch_ethtool.h
- removed file, no longer using ETHTOOL namespace.
drivers/net/chelsio/common.h
- moved code from osdep.h to common.h
- added comment to #endif indicating which symbol it closes.
drivers/net/chelsio/cphy.h
- removed dead code.
- added comment to #endif indicating which symbol it closes.
drivers/net/chelsio/cxgb2.c
- use DMA_{32,64}BIT_MASK in include/linux/dma-mapping.h.
- removed unused code.
- use printk message for link info resembling drivers/net/mii.c.
- no longer using the MODULE_xxx namespace.
- no longer using "pci_" namespace.
- no longer using ETHTOOL namespace.
drivers/net/chelsio/cxgb2.h
- removed file, merged into common.h
drivers/net/chelsio/elmer0.h
- removed dead code.
- added various enums.
- added comment to #endif indicating which symbol it closes.
drivers/net/chelsio/espi.c
- removed various macros, using native kernel calls now.
- removed a lot of wrappers, including t1_read/write_reg_4.
drivers/net/chelsio/espi.h
- added comment to #endif indicating which symbol it closes.
drivers/net/chelsio/gmac.h
- added comment to #endif indicating which symbol it closes.
drivers/net/chelsio/mv88x201x.c
- changes to sync with Chelsio TOT.
drivers/net/chelsio/osdep.h
- removed file, consolidation. osdep was used to translate wrapper functions
since our code supports multiple OSs. removed wrappers.
drivers/net/chelsio/pm3393.c
- removed various macros, using native kernel calls now.
- removed a lot of wrappers, including t1_read/write_reg_4.
- removed unused code.
drivers/net/chelsio/regs.h
- added a few register entries for future and current feature support.
- added comment to #endif indicating which symbol it closes.
drivers/net/chelsio/sge.c
- rewrote large portion of scatter-gather engine to stabilize
performance.
- using u8/u16/u32 kernel types instead of __u8/__u16/__u32 compiler
types.
drivers/net/chelsio/sge.h
- rewrote large portion of scatter-gather engine to stabilize
performance.
- added comment to #endif indicating which symbol it closes.
drivers/net/chelsio/subr.c
- merged tp.c into subr.c
- removed various macros, using native kernel calls now.
- removed a lot of wrappers, including t1_read/write_reg_4.
- removed unused code.
drivers/net/chelsio/suni1x10gexp_regs.h
- modified copyright and authorship of file.
- added comment to #endif indicating which symbol it closes.
drivers/net/chelsio/tp.c
- removed file, merged into subr.c.
drivers/net/chelsio/tp.h
- removed file.
include/linux/pci_ids.h
- patched to include PCI_VENDOR_ID_CHELSIO 0x1425, removed define from
our code.
A Linux driver for the Chelsio 10Gb Ethernet Network Controller by Chelsio
(http://www.chelsio.com). This driver supports the Chelsio N210 NIC and is
backward compatible with the Chelsio N110 model 10Gb NICs. It supports
AMD64, EM64T and x86 systems.
Signed-off-by: Tina Yang <tinay@chelsio.com>
Signed-off-by: Scott Bardone <sbardone@chelsio.com>
Signed-off-by: Christoph Lameter <christoph@lameter.com>
Adrian said:
- my3126.c is unused (because t1_my3126_ops isn't used anywhere)
- what are the EXTRA_CFLAGS in drivers/net/chelsio/Makefile for?
- $(cxgb-y) in drivers/net/chelsio/Makefile seems to be unneeded
- completely unused global functions:
- espi.c: t1_espi_get_intr_counts
- sge.c: t1_sge_get_intr_counts
- the following functions can be made static:
- sge.c: t1_espi_workaround
- sge.c: t1_sge_tx
- subr.c: __t1_tpi_read
- subr.c: __t1_tpi_write
- subr.c: t1_wait_op_done
shemminger said:
The performance recommendations in cxgb.txt are common to all fast devices,
and should be in one file rather than just for this device. I would rather
see ip-sysctl.txt updated or a new file on tuning recommendations started.
Some of them have consequences that aren't documented well.
For example, turning off TCP timestamps risks data corruption from sequence wrap.
A new driver shouldn't need so may #ifdef's unless you want to putit on older
vendor versions of 2.4
Some accessor and wrapper functions like:
t1_pci_read_config_4
adapter_name
t1_malloc
are just annoying noise.
Why have useless dead code like:
/* Interrupt handler */
+static int pm3393_interrupt_handler(struct cmac *cmac)
+{
+ u32 master_intr_status;
+/*
+ 1. Read master interrupt register.
+ 2. Read BLOCK's interrupt status registers.
+ 3. Handle BLOCK interrupts.
+*/
Jeff said:
step 1: kill all the OS wrappers.
And do you really need hooks for multiple MACs, when only one MAC is
really supported? Typically these hooks are at a higher level anyway --
struct net_device.
From: Christoph Lameter <christoph@lameter
Driver modified as suggested by Pekka Enberg, Stephen Hemminger and Andrian
Bunk. Reduces the size of the driver to ~260k.
- clean up tabs
- removed my3126.c
- removed 85% of suni1x10gexp_regs.h
- removed 80% of regs.h
- removed various calls, renamed variables/functions.
- removed system specific and other wrappers (usleep, msleep)
- removed dead code
- dropped redundant casts in osdep.h
- dropped redundant check of kfree
- dropped weird code (MODVERSIONS stuff)
- reduced number of #ifdefs
- use kcalloc now instead of kmalloc
- Add information about known issues with the driver
- Add information about authors
Signed-off-by: Scott Bardone <sbardone@chelsio.com>
Signed-off-by: Christoph Lameter <christoph@lameter.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
diff -puN /dev/null Documentation/networking/cxgb.txt
Alexey Dobriyan
Patrick McHardy