Changes to last version:
- use netdev_alloc_skb
- make init_rx_bufs just fail and not panic, if skb alloc fails
- don/t free_irq, if request_irq failed
Thomas.
Extracted chip specific code out of lasi_82596.c and placed into a lib82596.c
to make it usable for other 82596 drivers
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de> Signed-off-by: Jeff Garzik <jeff@garzik.org>
Francois Romieu [Wed, 31 Jan 2007 22:47:43 +0000 (23:47 +0100)]
r8169: mac address change support
Merged from Realtek's r8169-6.001 driver.
I have added some locking to protect against the arp monitoring
timer in the bonding driver. Accessing the configuration registers
is otherwise performed under RTNL locking.
Signed-off-by: Francois Romieu <romieu@fr.zoreil.com> Cc: Edward Hsu <edward_hsu@realtek.com.tw>
Francois Romieu [Wed, 21 Feb 2007 21:40:46 +0000 (22:40 +0100)]
r8169: cleanup
No functionnal change:
- trim the old history log
- whitespace/indent/case police
- unsigned int where signedness does not matter
- removal of obsolete assert
- needless cast from void * (dev_instance)
- remove dead code once related to power management
- use netdev_alloc_skb.
Signed-off-by: Francois Romieu <romieu@fr.zoreil.com> Cc: Stephen Hemminger <shemminger@linux-foundation.org> Cc: Edward Hsu <edward_hsu@realtek.com.tw>
Francois Romieu [Tue, 20 Feb 2007 21:20:51 +0000 (22:20 +0100)]
r8169: confusion between hardware and IP header alignment
The rx copybreak part is straightforward.
The align field in struct rtl_cfg_info is related to the alignment
requirements of the DMA operation. Its value is set at 2 to limit the
scale of possible regression but my old v1.21 8169 datasheet claims a
8 bytes requirements (which never appeared in the driver, of course)
and the 8101/8168 go with a plain 8 bytes alignment.
Signed-off-by: Francois Romieu <romieu@fr.zoreil.com> Cc: Edward Hsu <edward_hsu@realtek.com.tw>
Francois Romieu [Mon, 19 Feb 2007 23:00:26 +0000 (00:00 +0100)]
r8169: merge with version 8.001.00 of Realtek's r8168 driver
This one includes:
- more tweaks to rtl_hw_start_8168
- a work around for a Rx FiFO overflow issue on the 8168Bb
- rtl8169_{intr_mask/napi_event} are replaced with per-device fields,
namely tp->{intr/napi}_event
- rtl_cfg_info is converted to C99 for readability but the values are
not changed for the 8169/8110 and the 8101
Includes ChipCmd fix from Bernhard Walle <bwalle@suse.de> (2007/02/24).
Signed-off-by: Francois Romieu <romieu@fr.zoreil.com> Cc: Edward Hsu <edward_hsu@realtek.com.tw>
Francois Romieu [Tue, 13 Feb 2007 22:38:05 +0000 (23:38 +0100)]
r8169: merge with version 6.001.00 of Realtek's r8169 driver
- new identifier for the 8110SCe
- the PCI latency timer is set unconditionally. This part is identical
in Realtek's r8168 (8.001.00) and r8101 (1.001.00)
- initialization of the cache line size register is for the 8169s only
- more magic in rtl_hw_start_8169
- it is not possible to factor out the setting of the the irq event mask
with the 8168 and the 8101 any more. Pushed it into the hw_start handler.
- rtl_set_rx_tx_config_registers() and write to the ChipCmd register are
issued identically for the whole 8169/8110 family: the 8110SCd/8110SCe
are handled the same way
- work around for AMD platform.
Some registers definitions in Realtek's driver are let aside for later.
Signed-off-by: Francois Romieu <romieu@fr.zoreil.com> Cc: Edward Hsu <edward_hsu@realtek.com.tw>
Francois Romieu [Fri, 23 Feb 2007 22:36:39 +0000 (23:36 +0100)]
r8169: add hooks for per-device hw_start handler
Rationale: rtl8169_hw_start will not help maintaining an unified
driver for different chipsets but people at Realtek are probably
too polite to say it distinctly.
Let's add the hook and keep hw_start handler unchanged.
As can be seen from the content of rtl8169_pci_tbl, the RTL_CFG_1
entry in rtl_cfg_info was unused. I recycled it for the 0x8168.
Signed-off-by: Francois Romieu <romieu@fr.zoreil.com> Cc: Edward Hsu <edward_hsu@realtek.com.tw>
- pci_dma_sync_single_for_cpu is not needed for a single large packet
- remove the function pointer to help gcc optimizing the inline
pci_dma functions.
Signed-off-by: Stephen Hemminger <shemminger@linux-foundation.org> Signed-off-by: Francois Romieu <romieu@fr.zoreil.com> Cc: Edward Hsu <edward_hsu@realtek.com.tw>
Francois Romieu [Sat, 16 Jun 2007 21:28:45 +0000 (23:28 +0200)]
r8169: de-obfuscate modulo arithmetic
The former style suggests a modulo arithmetic misuse but
the expression should never be < 0. Even if it does, the
driver will simply loop longer than expected (not that
the remaining parts of the system will necessarily
appreciate it...).
Let's warn the user when something goes wrong and try
to go over it.
Signed-off-by: Francois Romieu <romieu@fr.zoreil.com> Cc: Edward Hsu <edward_hsu@realtek.com.tw>
Enable support for Yukon EX chipset (88e8071).
Most of changes are related to new commands to chip for transmit,
and change in status and checksumming.
Signed-off-by: Stephen Hemminger <shemminger@linux-foundation.org> Signed-off-by: Jeff Garzik <jeff@garzik.org>
The General Purpose I/O register is yet another hardware workaround
catchall. Enable workaround that vendor driver does to stay
but for bug compatiable.
Signed-off-by: Stephen Hemminger <shemminger@linux-foundation.org> Signed-off-by: Jeff Garzik <jeff@garzik.org>
On Yukon EX reading some of the undocumented places in the
memory space will cause a hang. Since they don't provide useful
information, just skip the reserved areas.
Signed-off-by: Stephen Hemminger <shemminger@linux-foundation.org> Signed-off-by: Jeff Garzik <jeff@garzik.org>
Linas Vepstas [Mon, 11 Jun 2007 19:09:16 +0000 (14:09 -0500)]
spidernet: fix misnamed flag
The transmit frame tail bit is stranglely misnamed as
"no checksum". Fix the name to what it should be:
"transmit frame tail". No functional change,
just a name change.
Signed-off-by: Linas Vepstas <linas@austin.ibm.com> Signed-off-by: Jeff Garzik <jeff@garzik.org>
The code for checksum is more complex than needed when dealing with VLAN's;
the higher layers already pass down the location of the IP header.
Compile tested only, no hardware available.
Signed-off-by: Stephen Hemminger <shemminger@linux-foundation.org> Signed-off-by: Ron Mercer <ron.mercer@qlogic.com> Signed-off-by: Jeff Garzik <jeff@garzik.org>
Jan Engelhardt [Wed, 13 Jun 2007 19:48:53 +0000 (12:48 -0700)]
Use menuconfig objects II - netdev (general+100mbit)
CONFIG_NETDEVICES, CONFIG_NET_ETHERNET:
Change Kconfig objects from "menu, config" into "menuconfig" so
that the user can disable the whole feature without having to
enter the menu first.
CONFIG_SMC9194:
Move it so that it appears correctly in menuconfig.
Signed-off-by: Jan Engelhardt <jengelh@gmx.de> Cc: Jeff Garzik <jeff@garzik.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Jeff Garzik <jeff@garzik.org>
Divy Le Ray [Thu, 31 May 2007 04:10:58 +0000 (21:10 -0700)]
cxgb3 - TP SRAM update
The chip executes microcode present in internal RAM,
whose content is loaded from EEPROM on power cycle.
This patch allows an update of the microcode through PIO
without forcing a power cycle.
Signed-off-by: Divy Le Ray <divy@chelsio.com> Signed-off-by: Jeff Garzik <jeff@garzik.org>
Kapil Juneja [Fri, 11 May 2007 23:25:11 +0000 (18:25 -0500)]
gianfar: add support for SGMII
Add code for initialising and configuring TBI interface and
programming it for connecting to on-chip SERDES (Lynx PHY)
in case of SGMII mode selected through HRCW at reset.
also add defines for TBI register configuration. TBI
interface is programmed towards the SERDES.
refactored mdio read/write functions to differentiate
programming local interface MII regs (e.g., for TBI) from
always programming the mdio master (TSEC1, for programming
the PHYs).
Signed-off-by: Kapil Juneja <Kapil.Juneja@freescale.com> Signed-off-by: Andy Fleming <afleming@freescale.com> Signed-off-by: Kim Phillips <kim.phillips@freescale.com> Signed-off-by: Jeff Garzik <jeff@garzik.org>
The ICPlus IP175C sports a 100Mbit/s 4-port switch in addition
to a dedicated 100Mbit/s WAN port.
Signed-off-by: Michael Barkowski <michael.barkowski@freescale.com> Signed-off-by: Kim Phillips <kim.phillips@freescale.com> Signed-off-by: Jeff Garzik <jeff@garzik.org>
Jouni Malinen [Mon, 28 May 2007 16:38:49 +0000 (09:38 -0700)]
[PATCH] hostap: Remove driver version number
The driver version number has not been updated since the driver was
included in the main kernel tree and there is no plan on updating this
in the future either. At this point, the only correct way to refer to
the version is to use the kernel version. The 0.4.4 version is
confusing since there are external version with higher version number
even though they are not actually any newer than the in-tree version.
Let's get rid of the version number in the kernel tree in order to
avoid this kind of confusion.
Signed-off-by: Jouni Malinen <j@w1.fi> Signed-off-by: John W. Linville <linville@tuxdriver.com>
Akinobu Mita [Sun, 27 May 2007 14:27:40 +0000 (23:27 +0900)]
[PATCH] softmac: use list_for_each_entry
Cleanup using list_for_each_entry.
Cc: Johannes Berg <johannes@sipsolutions.net> Cc: Joe Jezak <josejx@gentoo.org> Cc: Daniel Drake <dsd@gentoo.org> Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com> Signed-off-by: John W. Linville <linville@tuxdriver.com>
Daniel Drake [Thu, 24 May 2007 00:07:15 +0000 (01:07 +0100)]
[PATCH] zd1211rw: Make CCK gain patching conditional on RF type
The vendor driver code suggests that CR47 patching happens on every channel
change for every RF (depending on bit 8 in POD).
Due to a bug in their driver (upper bits of RF_Mode get zeroed out, then
are examined for 1s when setting some other flags), this isn't actually
what happens, and their generic CCK patching routine never takes effect.
Some of their RF configurations do include explicit (duplicated) code
for CR47 patching though. This patch makes zd1211rw match that
behaviour.
Signed-off-by: Daniel Drake <dsd@gentoo.org> Signed-off-by: John W. Linville <linville@tuxdriver.com>
Daniel Drake [Thu, 24 May 2007 00:06:53 +0000 (01:06 +0100)]
[PATCH] zd1211rw: Add UW2453 RF support
This patch adds support for another radio appearing in new devices: the
Ubec UW2453. It's more complicated than the other RF's we support, but
Ubec publish full tech specs so we're able to understand the vendor code
relatively well.
Now that we support UW2453, we also support Atheros' new USB chip: the
AR5007UG. From the little info we have, this appears to be just a
rebranded ZD1211B.
This RF code doesn't work very well -- lots more TX/RX errors than the
other RFs. However, the vendor driver doesn't do any better, so this is
all we can do for now.
[kune@deine-taler.de: bug fixes] Signed-off-by: Daniel Drake <dsd@gentoo.org> Signed-off-by: John W. Linville <linville@tuxdriver.com>
Daniel Drake [Thu, 24 May 2007 00:06:41 +0000 (01:06 +0100)]
[PATCH] zd1211rw: Extend RF layer
These changes are needed for UW2453 RF support:
Add pointer which RF drivers can use to store private RF data
Add exit hook so that RF drivers can free private data
Allow RF's to disable the generic TX power integration handling code
Signed-off-by: Daniel Drake <dsd@gentoo.org> Signed-off-by: John W. Linville <linville@tuxdriver.com>
Ivo van Doorn [Mon, 14 May 2007 21:06:01 +0000 (23:06 +0200)]
[PATCH] eeprom_93cx6: Add comment for 1us delay after pulse
This will add a comment for the 1us delay which is taken
after the pulse has been switched. The 1us delay is based
on the specifications so that should be made clear.
Signed-off-by: Ivo van Doorn <IvDoorn@gmail.com> Signed-off-by: John W. Linville <linville@tuxdriver.com>
Fix permission checking for the new utimensat() system call
Commit 1c710c896eb461895d3c399e15bb5f20b39c9073 added the utimensat()
system call, but didn't handle the case of checking for the writability
of the target right, when the target was a file descriptor, not a
filename.
We cannot use vfs_permission(MAY_WRITE) for that case, and need to
simply check whether the file descriptor is writable. The oops from
using the wrong function was noticed and narrowed down by Markus
Trippelsdorf.
Cc: Ulrich Drepper <drepper@redhat.com> Cc: Markus Trippelsdorf <markus@trippelsdorf.de> Cc: Andrew Morton <akpm@linux-foundation.org> Acked-by: Al Viro <viro@ftp.linux.org.uk> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
PIO4 is a maximum PIO mode supported by a driver. Using "255" as a max_mode
argument to ide_get_best_pio_mode() could result in wrong timings being used
by a driver (for "pio" equal to 5) or OOPS (for "pio" values > 5 && < 255).
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com> Acked-by: Sergei Shtylyov <sshtylyov@ru.mvista.com> Reviewed-by: Alan Cox <alan@lxorguk.ukuu.org.uk>
If the chipset is using this PCI-ID, the primary channel is connected to the
first PATA-port. The secondary channel is connected to SATA-ports in IDE
emulation mode. The legacy IO-ports are used.
The including of the PCI-ID into pata_sis is not sufficient, because the legacy
driver in drivers/ide is initialized before pata_sis.
Adrian Bunk [Sat, 7 Jul 2007 04:14:02 +0000 (06:14 +0200)]
DLM must depend on SYSFS
The dependency of DLM on SYSFS got lost in
commit 6ed7257b46709e87d79ac2b6b819b7e0c9184998 resulting in the
following compile error with CONFIG_DLM=y, CONFIG_SYSFS=n:
<-- snip -->
...
LD .tmp_vmlinux1
fs/built-in.o: In function `dlm_lockspace_init':
/home/bunk/linux/kernel-2.6/linux-2.6.22-rc6-mm1/fs/dlm/lockspace.c:231: undefined reference to `kernel_subsys'
fs/built-in.o: In function `configfs_init':
/home/bunk/linux/kernel-2.6/linux-2.6.22-rc6-mm1/fs/configfs/mount.c:143: undefined reference to `kernel_subsys'
make[1]: *** [.tmp_vmlinux1] Error 1
<-- snip -->
Signed-off-by: Adrian Bunk <bunk@stusta.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Adrian Bunk [Fri, 6 Jul 2007 22:54:09 +0000 (00:54 +0200)]
include/linux/kallsyms.h must #include <linux/errno.h>
This patch fixes the following 2.6.22 regression with CONFIG_KALLSYMS=n:
<-- snip -->
...
CC arch/m32r/kernel/traps.o
In file included from /home/bunk/linux/kernel-2.6/linux-2.6.22-rc6-mm1/arch/m32r/kernel/traps.c:14:
/home/bunk/linux/kernel-2.6/linux-2.6.22-rc6-mm1/include/linux/kallsyms.h: In function 'lookup_symbol_name':
/home/bunk/linux/kernel-2.6/linux-2.6.22-rc6-mm1/include/linux/kallsyms.h:66: error: 'ERANGE' undeclared (first use in this function)
/home/bunk/linux/kernel-2.6/linux-2.6.22-rc6-mm1/include/linux/kallsyms.h:66: error: (Each undeclared identifier is reported only once
/home/bunk/linux/kernel-2.6/linux-2.6.22-rc6-mm1/include/linux/kallsyms.h:66: error: for each function it appears in.)
/home/bunk/linux/kernel-2.6/linux-2.6.22-rc6-mm1/include/linux/kallsyms.h: In function 'lookup_symbol_attrs':
/home/bunk/linux/kernel-2.6/linux-2.6.22-rc6-mm1/include/linux/kallsyms.h:71: error: 'ERANGE' undeclared (first use in this function)
make[2]: *** [arch/m32r/kernel/traps.o] Error 1
<-- snip -->
Signed-off-by: Adrian Bunk <bunk@stusta.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
David Woodhouse [Sat, 7 Jul 2007 18:58:39 +0000 (14:58 -0400)]
Fix use-after-free oops in Bluetooth HID.
When cleaning up HIDP sessions, we currently close the ACL connection
before deregistering the input device. Closing the ACL connection
schedules a workqueue to remove the associated objects from sysfs, but
the input device still refers to them -- and if the workqueue happens to
run before the input device removal, the kernel will oops when trying to
look up PHYSDEVPATH for the removed input device.
Fix this by deregistering the input device before closing the
connections.
Merge branch 'master' of master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6
* 'master' of master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6:
[NETPOLL]: Fixups for 'fix soft lockup when removing module'
[NET]: net/core/netevent.c should #include <net/netevent.h>
[NETFILTER]: nf_conntrack_h323: add checking of out-of-range on choices' index values
[NET] skbuff: remove export of static symbol
SCTP: Add scope_id validation for link-local binds
SCTP: Check to make sure file is valid before setting timeout
SCTP: Fix thinko in sctp_copy_laddrs()
He correctly updated many of the function definitions that were using this
extra regs pointer parameter but forgot to update some caller sites of
those functions. The reason the modifications was not properly done on all
drivers is that some drivers were rarely compiled because they are for
AMIGA, or that some code sites were inside #ifdefs where the option is not
set or inside #if 0.
Here is the semantic patch that found the occurences
and fixed the problem.
arch/i386/kernel/built-in.o(.init.text+0x4fa9): In function `acpi_parse_madt':
: undefined reference to `acpi_madt_oem_check'
arch/i386/kernel/built-in.o(.init.text+0x7406): In function `smp_read_mpc':
: undefined reference to `mps_oem_check'
arch/i386/kernel/built-in.o(.init.text+0x8990): In function
`connect_bsp_APIC':
: undefined reference to `enable_apic_mode'
make: *** [.tmp_vmlinux1] Error 1
o Fix the build issue. Provided the definitions of missing functions.
o Don't have ES7000 machine. Only compile tested.
Cc: Len Brown <lenb@kernel.org> Cc: Natalie Protasevich <protasnb@gmail.com> Cc: Roland Dreier <rolandd@cisco.com> Cc: Andi Kleen <ak@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
PNP SMCf010 quirk: work around Toshiba Portege 4000 ACPI issues
When we enable the SMCf010 IR device, the Toshiba Portege 4000 BIOS claims
the device is working, but it really isn't configured correctly. The BIOS
*will* configure it, but only if we call _SRS after (1) reversing the order
of the SIR and FIR I/O port regions and (2) changing the IRQ from
active-high to active-low.
This patch addresses the 2.6.22 regression:
"no irda0 interface (2.6.21 was OK), smsc does not find chip"
I tested this on a Portege 4000. The smsc-ircc2 driver correctly detects
the device, and "irattach irda0 -s && irdadump" shows transmitted and
received packets.
Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com> Cc: Andrey Borzenkov <arvidjaar@mail.ru> Cc: Samuel Ortiz <samuel@sortiz.org> Cc: "Linus Walleij (LD/EAB)" <linus.walleij@ericsson.com> Cc: Michal Piotrowski <michal.k.k.piotrowski@gmail.com> Cc: Adam Belay <ambx1@neo.rr.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
David Woodhouse [Fri, 6 Jul 2007 09:39:52 +0000 (02:39 -0700)]
x86_64: fix headers_install
A bug in headers_install for ARCH=x86_64 yields an asm/ directory full of
files all of which are using the same #ifdef guard, "__ASM_STUB_" with no
postfix. So the second and later asm files #included in the same C file
(often through standard headers like ioctl.h) yields no symbols.
Strangeness with the Ubuntu 'tell me if I support something that's not
explcitly mentioned in POSIX, and I'll strip it out' shell, I believe.
We don't need the 'export' but we do need a semicolon at the end of the
FNAME line:
Signed-off-by: David Woodhouse <dwmw2@infradead.org> Signed-off-by: Rob Landley <rob@landley.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
MTRR: Fix race causing set_mtrr to go into infinite loop
Processors synchronization in set_mtrr requires the .gate field to be set
after .count field is properly initialized. Without an explicit barrier,
the compiler was reordering those memory stores. That was sometimes
causing a processor (in ipi_handler) to see the .gate change and decrement
.count before the latter is set by set_mtrr() (which then hangs in a
infinite loop with irqs disabled).
Jason Wessel [Fri, 6 Jul 2007 09:39:50 +0000 (02:39 -0700)]
i386: fix regression, endless loop in ptrace singlestep over an int80
The commit 635cf99a80f4ebee59d70eb64bb85ce829e4591f introduced a
regression. Executing a ptrace single step after certain int80
accesses will infinitely loop and never advance the PC.
The TIF_SINGLESTEP check should be done on the return from the syscall
and not before it.
I loops on each single step on the pop right after the int80 which writes out
to the console. At that point you can issue as many single steps as you want
and it will not advance any further.
The test case is below:
/* Test whether singlestep through an int80 syscall works.
*/
#define _GNU_SOURCE
#include <stdio.h>
#include <unistd.h>
#include <fcntl.h>
#include <sys/ptrace.h>
#include <sys/wait.h>
#include <sys/mman.h>
#include <asm/user.h>
#include <string.h>
static int child, status;
static struct user_regs_struct regs;
Fix elf_core_dump() when writing arch specific notes (spu coredumps)
elf_core_dump() supports dumping arch specific ELF notes, via the #define
ELF_CORE_WRITE_EXTRA_NOTES. Currently the only user of this is the powerpc
spu coredump code.
There is a bug in the handling of foffset WRT the arch notes, which causes
us to erroneously increment foffset by the size of the arch notes, leaving
a block of zeroes in the file, and causing all subsequent data in the file
to be at <supposed position> + <arch note size>. eg:
LOAD 0x050000 0x00100000 0x00000000 0x20000 0x20000 R E 0x10000
Tells us we should have a chunk of data at 0x50000. The truth is the data
is at 0x90dbc = 0x50000 + 0x40dbc (the size of the arch notes).
This bug prevents gdb from reading the core file correctly.
The simplest fix is to simply remember the size of the arch notes, and add
it to foffset after we've written the arch notes. The only drawback is
that if the arch code doesn't write as many bytes as it said it would, we
end up with a broken core dump again. For now I think that's a reasonable
requirement.
Tested on a Cell blade, gdb no longer complains about the core file being
bogus.
While I'm here I should point out that the spu coredump code does not work
if we're dumping to a pipe - we'll have to wait for 23 to fix that.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au> Acked-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Acked-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Ralf Baechle [Wed, 20 Jun 2007 23:22:34 +0000 (00:22 +0100)]
[MIPS] Fix scheduling latency issue on 24K, 34K and 74K cores
The idle loop goes to sleep using the WAIT instruction if !need_resched().
This has is suffering from from a race condition that if if just after
need_resched has returned 0 an interrupt might set TIF_NEED_RESCHED but
we've just completed the test so go to sleep anyway. This would be
trivial to fix by just disabling interrupts during that sequence as in:
local_irq_disable();
if (!need_resched())
__asm__("wait");
local_irq_enable();
but the processor architecture leaves it undefined if a processor calling
WAIT with interrupts disabled will ever restart its pipeline and indeed
some processors have made use of the freedom provided by the architecture
definition. This has been resolved and the Config7.WII bit indicates that
the use of WAIT is safe on 24K, 24KE and 34K cores. It also is safe on
74K starting revision 2.1.0 so enable the use of WAIT with interrupts
disabled for 74K based on a c0_prid of at least that.
projects / linux-2.6 / log