Tom Zanussi [Tue, 6 Sep 2005 22:16:30 +0000 (15:16 -0700)]
[PATCH] relayfs
Here's the latest version of relayfs, against linux-2.6.11-mm2. I'm hoping
you'll consider putting this version back into your tree - the previous
rounds of comment seem to have shaken out all the API issues and the number
of comments on the code itself have also steadily dwindled.
This patch is essentially the same as the relayfs redux part 5 patch, with
some minor changes based on reviewer comments. Thanks again to Pekka
Enberg for those. The patch size without documentation is now a little
smaller at just over 40k. Here's a detailed list of the changes:
- removed the attribute_flags in relay open and changed it to a
boolean specifying either overwrite or no-overwrite mode, and removed
everything referencing the attribute flags.
- added a check for NULL names in relayfs_create_entry()
- got rid of the unnecessary multiple labels in relay_create_buf()
- some minor simplification of relay_alloc_buf() which got rid of a
couple params
- updated the Documentation
In addition, this version (through code contained in the relay-apps tarball
linked to below, not as part of the relayfs patch) tries to make it as easy
as possible to create the cooperating kernel/user pieces of a typical and
common type of logging application, one where kernel logging is kicked off
when a user space data collection app starts and stops when the collection
app exits, with the data being automatically logged to disk in between. To
create this type of application, you basically just include a header file
(relay-app.h, included in the relay-apps tarball) in your kernel module,
define a couple of callbacks and call an initialization function, and on
the user side call a single function that sets up and continuously monitors
the buffers, and writes data to files as it becomes available. Channels
are created when the collection app is started and destroyed when it exits,
not when the kernel module is inserted, so different channel buffer sizes
can be specified for each separate run via command-line options. See the
README in the relay-apps tarball for details.
Also included in the relay-apps tarball are a couple examples
demonstrating how you can use this to create quick and dirty kernel
logging/debugging applications. They are:
- tprintk, short for 'tee printk', which temporarily puts a kprobe on
printk() and writes a duplicate stream of printk output to a relayfs
channel. This could be used anywhere there's printk() debugging code
in the kernel which you'd like to exercise, but would rather not have
your system logs cluttered with debugging junk. You'd probably want
to kill klogd while you do this, otherwise there wouldn't be much
point (since putting a kprobe on printk() doesn't change the output
of printk()). I've used this method to temporarily divert the packet
logging output of the iptables LOG target from the system logs to
relayfs files instead, for instance.
- klog, which just provides a printk-like formatted logging function
on top of relayfs. Again, you can use this to keep stuff out of your
system logs if used in place of printk.
This patch adds a new kernel debug feature: CONFIG_DETECT_SOFTLOCKUP.
When enabled then per-CPU watchdog threads are started, which try to run
once per second. If they get delayed for more than 10 seconds then a
callback from the timer interrupt detects this condition and prints out a
warning message and a stack dump (once per lockup incident). The feature
is otherwise non-intrusive, it doesnt try to unlock the box in any way, it
only gets the debug info out, automatically, and on all CPUs affected by
the lockup.
ATM pthread_cond_signal is unnecessarily slow, because it wakes one waiter
(which at least on UP usually means an immediate context switch to one of
the waiter threads). This waiter wakes up and after a few instructions it
attempts to acquire the cv internal lock, but that lock is still held by
the thread calling pthread_cond_signal. So it goes to sleep and eventually
the signalling thread is scheduled in, unlocks the internal lock and wakes
the waiter again.
Now, before 2003-09-21 NPTL was using FUTEX_REQUEUE in pthread_cond_signal
to avoid this performance issue, but it was removed when locks were
redesigned to the 3 state scheme (unlocked, locked uncontended, locked
contended).
Following scenario shows why simply using FUTEX_REQUEUE in
pthread_cond_signal together with using lll_mutex_unlock_force in place of
lll_mutex_unlock is not enough and probably why it has been disabled at
that time:
The number is value in cv->__data.__lock.
thr1 thr2 thr3
0 pthread_cond_wait
1 lll_mutex_lock (cv->__data.__lock)
0 lll_mutex_unlock (cv->__data.__lock)
0 lll_futex_wait (&cv->__data.__futex, futexval)
0 pthread_cond_signal
1 lll_mutex_lock (cv->__data.__lock)
1 pthread_cond_signal
2 lll_mutex_lock (cv->__data.__lock)
2 lll_futex_wait (&cv->__data.__lock, 2)
2 lll_futex_requeue (&cv->__data.__futex, 0, 1, &cv->__data.__lock)
# FUTEX_REQUEUE, not FUTEX_CMP_REQUEUE
2 lll_mutex_unlock_force (cv->__data.__lock)
0 cv->__data.__lock = 0
0 lll_futex_wake (&cv->__data.__lock, 1)
1 lll_mutex_lock (cv->__data.__lock)
0 lll_mutex_unlock (cv->__data.__lock)
# Here, lll_mutex_unlock doesn't know there are threads waiting
# on the internal cv's lock
Now, I believe it is possible to use FUTEX_REQUEUE in pthread_cond_signal,
but it will cost us not one, but 2 extra syscalls and, what's worse, one of
these extra syscalls will be done for every single waiting loop in
pthread_cond_*wait.
We would need to use lll_mutex_unlock_force in pthread_cond_signal after
requeue and lll_mutex_cond_lock in pthread_cond_*wait after lll_futex_wait.
Another alternative is to do the unlocking pthread_cond_signal needs to do
(the lock can't be unlocked before lll_futex_wake, as that is racy) in the
kernel.
I have implemented both variants, futex-requeue-glibc.patch is the first
one and futex-wake_op{,-glibc}.patch is the unlocking inside of the kernel.
The kernel interface allows userland to specify how exactly an unlocking
operation should look like (some atomic arithmetic operation with optional
constant argument and comparison of the previous futex value with another
constant).
It has been implemented just for ppc*, x86_64 and i?86, for other
architectures I'm including just a stub header which can be used as a
starting point by maintainers to write support for their arches and ATM
will just return -ENOSYS for FUTEX_WAKE_OP. The requeue patch has been
(lightly) tested just on x86_64, the wake_op patch on ppc64 kernel running
32-bit and 64-bit NPTL and x86_64 kernel running 32-bit and 64-bit NPTL.
With the following benchmark on UP x86-64 I get:
for i in nptl-orig nptl-requeue nptl-wake_op; do echo time elf/ld.so --library-path .:$i /tmp/bench; \
for j in 1 2; do echo ( time elf/ld.so --library-path .:$i /tmp/bench ) 2>&1; done; done
time elf/ld.so --library-path .:nptl-orig /tmp/bench
real 0m0.655s user 0m0.253s sys 0m0.403s
real 0m0.657s user 0m0.269s sys 0m0.388s
time elf/ld.so --library-path .:nptl-requeue /tmp/bench
real 0m0.496s user 0m0.225s sys 0m0.271s
real 0m0.531s user 0m0.242s sys 0m0.288s
time elf/ld.so --library-path .:nptl-wake_op /tmp/bench
real 0m0.380s user 0m0.176s sys 0m0.204s
real 0m0.382s user 0m0.175s sys 0m0.207s
The benchmark is at:
http://sourceware.org/ml/libc-alpha/2005-03/txt00001.txt
Older futex-requeue-glibc.patch version is at:
http://sourceware.org/ml/libc-alpha/2005-03/txt00002.txt
Older futex-wake_op-glibc.patch version is at:
http://sourceware.org/ml/libc-alpha/2005-03/txt00003.txt
Will post a new version (just x86-64 fixes so that the patch
applies against pthread_cond_signal.S) to libc-hacker ml soon.
Attached is the kernel FUTEX_WAKE_OP patch as well as a simple-minded
testcase that will not test the atomicity of the operation, but at least
check if the threads that should have been woken up are woken up and
whether the arithmetic operation in the kernel gave the expected results.
This patch adds some missing pci-related calls to the suspend and resume
routines of the 3c59x driver. It also makes the driver free/request IRQ on
suspend/resume, in accordance with the proposal at:
http://lists.osdl.org/pipermail/linux-pm/2005-May/000955.html
Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
[PATCH] x86_64: create sysfs entries for cpu only for present cpus
Need to create sysfs only for cpus that are present. Without which we see
NR_CPUS entries created when we have CONFIG_HOTPLUG and CONFIG_HOTPLUG_CPU
enabled.
Eric Dumazet [Tue, 6 Sep 2005 22:16:17 +0000 (15:16 -0700)]
[PATCH] x86_64: prefetchw() can fall back to prefetch() if !3DNOW
This is a multi-part message in MIME format. If the cpu lacks 3DNOW
feature, we can use a normal prefetcht0 instruction instead of NOP5.
"prefetchw (%rxx)" and "prefetcht0 (%rxx)" have the same length, ranging
from 3 to 5 bytes depending on the register. So this patch even helps
AMD64, shortening the length of the code.
Signed-off-by: Eric Dumazet <dada1@cosmosbay.com> Acked-by: Andi Kleen <ak@muc.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Zwane Mwaikambo [Tue, 6 Sep 2005 22:16:16 +0000 (15:16 -0700)]
[PATCH] x86_64: print processor number in show_regs
Up to date I've been using the GS value to determine the processor number
in dumps from show_regs, however this can be cumbersome to do if you don't
have the vmlinux to verify with the address of cpu_pda, how about the
following? I considered using hard_smp_processor_id for robustness but we
already dereference current so we're already relying on MSR_GS_BASE being
sane.
Signed-off-by: Zwane Mwaikambo <zwane@arm.linux.org.uk> Acked-by: Andi Kleen <ak@muc.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
[PATCH] x86/x86_64: deferred handling of writes to /proc/irqxx/smp_affinity
When handling writes to /proc/irq, current code is re-programming rte
entries directly. This is not recommended and could potentially cause
chipset's to lockup, or cause missing interrupts.
CONFIG_IRQ_BALANCE does this correctly, where it re-programs only when the
interrupt is pending. The same needs to be done for /proc/irq handling as well.
Otherwise user space irq balancers are really not doing the right thing.
- Changed pending_irq_balance_cpumask to pending_irq_migrate_cpumask for
lack of a generic name.
- added move_irq out of IRQ_BALANCE, and added this same to X86_64
- Added new proc handler for write, so we can do deferred write at irq
handling time.
- Display of /proc/irq/XX/smp_affinity used to display CPU_MASKALL, instead
it now shows only active cpu masks, or exactly what was set.
- Provided a common move_irq implementation, instead of duplicating
when using generic irq framework.
Tested on i386/x86_64 and ia64 with CONFIG_PCI_MSI turned on and off.
Tested UP builds as well.
MSI testing: tbd: I have cards, need to look for a x-over cable, although I
did test an earlier version of this patch. Will test in a couple days.
David Gibson [Tue, 6 Sep 2005 04:59:47 +0000 (14:59 +1000)]
[PATCH] Invert sense of SLB class bit
Currently, we set the class bit in kernel SLB entries, and clear it on
user SLB entries. On POWER5, ERAT entries created in real mode have
the class bit clear. So to avoid flushing kernel ERAT entries on each
context switch, this patch inverts our usage of the class bit, setting
it on user SLB entries and clearing it on kernel SLB entries.
Booted on POWER5 and G5.
Signed-off-by: David Gibson <dwg@au1.ibm.com> Signed-off-by: Paul Mackerras <paulus@samba.org>
Al Viro [Tue, 6 Sep 2005 06:35:41 +0000 (23:35 -0700)]
[SPARC64]: Kconfig fix (GEN_RTC dependencies)
Yet another architecture not coverd by GEN_RTC - sparc64 never picked
it until now and it doesn't have asm/rtc.h to go with it, so it
wouldn't compile anyway (or have these ioctls in the user-visible
headers, for that matter).
FWIW, I'm very tempted to introduce ARCH_HAS_GEN_RTC and have it set
in arch/*/Kconfig for architectures that know what to do with this
stuff - for something supposedly generic the list of architectures
where it doesn't work is getting too long...
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: David S. Miller <davem@davemloft.net>
Al Viro [Tue, 6 Sep 2005 06:30:15 +0000 (23:30 -0700)]
[MOXA]: Fix this driver properly.
Actually, proper fix of that breakage is embarrassingly simple - it's yet
another gratitious leftover include of asm/segment.h, so incremental to the
previos would be removal of that BROKEN and removal of bogus include from
mxser.c itself.
Signed-off-by: David S. Miller <davem@davemloft.net>
[PATCH] ppc64: Allow world readable /proc/ppc64/lparcfg
I would like to be able to read the lparcfg data from any user so we
can make "intelligent" decisions based on underlying attributes when
running in lpars. Yes there's software that likes to do this :) and
runs as non-root.
It's very similar to say VM where you can get CP to provide feedback
of the real hardware inside a VM guest.
Signed-off-by: Wim Coekaerts <wim.coekaerts@oracle.com> Signed-off-by: Paul Mackerras <paulus@samba.org>
Becky Bruce [Sun, 4 Sep 2005 00:01:57 +0000 (19:01 -0500)]
[PATCH] Move 3 more headers to asm-powerpc
Merged several nearly-identical header files from asm-ppc and asm-ppc64
into asm-powerpc.
Signed-off-by: Kumar Gala <kumar.gala@freescale.com> Signed-off-by: Becky Bruce <becky.bruce@freescale.com> Signed-off-by: Paul Mackerras <paulus@samba.org>
The following patch fixes 2 issues:
1) use PLATFORM_LPAR bit to test if running in LPAR mode
2) systemcfg pointer is assigned from static data in
arch/ppc64/kernel/pacaData.c. The file arch/ppc64/kernel/head.S
now refers to is using the GOT binding to the pointer and hence
must deref it.
Signed-off-by: Jimi Xenidis <jimix@watson.ibm.com> Signed-off-by: Paul Mackerras <paulus@samba.org>
Milton Miller [Tue, 6 Sep 2005 01:55:00 +0000 (11:55 +1000)]
[PATCH] ppc64: Clean up CR handling
Make the 16550 and real mode 16550 use tail recursion like the scc code
instead of repeating the routine except for the character sent.
Gcc recoginizes the tail recursion and handles it efficently without
stack allocations. The maple real putc shrinks from 188 to 104 bytes
of instructions. udbg_putc drops from 188 to 140 bytes.
Signed-off-by: Milton Miller <miltonm@bga.com> Signed-off-by: Anton Blanchard <anton@samba.org> Signed-off-by: Paul Mackerras <paulus@samba.org>
Herbert Xu [Tue, 6 Sep 2005 01:55:48 +0000 (18:55 -0700)]
[TCP]: Fix TCP_OFF() bug check introduced by previous change.
The TCP_OFF assignment at the bottom of that if block can indeed set
TCP_OFF without setting TCP_PAGE. Since there is not much to be
gained from avoiding this situation, we might as well just zap the
offset. The following patch should fix it.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
Herbert Xu [Tue, 6 Sep 2005 01:44:37 +0000 (18:44 -0700)]
[NET]: 2.6.13 breaks libpcap (and tcpdump)
Patrick McHardy says:
Never mind, I got it, we never fall through to the second switch
statement anymore. I think we could simply break when load_pointer
returns NULL. The switch statement will fall through to the default
case and return 0 for all cases but 0 > k >= SKF_AD_OFF.
Here's a patch to do just that.
I left BPF_MSH alone because it's really a hack to calculate the IP
header length, which makes no sense when applied to the special data.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
Michael Chan [Tue, 6 Sep 2005 00:53:32 +0000 (17:53 -0700)]
[TG3]: Use status tag to check for new events
Use the status tag to determine if there are new events in
tg3_interrupt_tagged(). We discussed about this a while ago with Grant
Grundler and DaveM. This scheme makes it unnecessary to clear the
updated bit in the status block when using tagged mode, and only
a simple comparison is needed to determine if there are new events.
The tp->lock around netif_rx_complete() and tg3_restart_ints() is also
removed. It is unnecessary with DaveM's new locking scheme.
Signed-off-by: Michael Chan <mchan@broadcom.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Michael Chan [Tue, 6 Sep 2005 00:53:19 +0000 (17:53 -0700)]
[TG3]: Remove status block access in tg3_msi() and add prefetches
Remove unnecessary status block accesses in tg3_msi(). Since MSI is
not shared, it is unnecessary to read the status block to determine if
there are any new events in the MSI handler. It is also unnecessary to
clear the updated bit in the status block.
Since the poll list is per-cpu, tg3_poll() will be scheduled to run on
the same CPU that received the MSI. Prefetches for the status block
and the next rx descriptors are added in tg3_msi() to improve their
access times when tg3_poll() runs.
In the non-MSI irq handlers, we need to check the status block because
interrupts may be shared. Only prefetches for the next rx descriptors
are added.
Signed-off-by: Michael Chan <mchan@broadcom.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Hannes Reinecke [Fri, 15 Jul 2005 08:09:25 +0000 (10:09 +0200)]
[PATCH] Floppy: Add cmos attribute to floppy driver
Currently only a device 'fdX' shows up in sysfs; the other possible
device for this drive (like fd0h1440 etc) must be guessed from there.
This patch corrects the floppy driver to create a platform device for
each floppy found; each platform device also has an attribute 'cmos'
which represents the cmos type for this drive. From this attribute the
other possible device types can be computed.
From: Hannes Reinecke <hare@suse.de> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
[PATCH] Driver core: link device and all class devices derived from it.
Driver core: link device and all class devices derived from it.
To ease the task of locating class devices derived from a certain
device create symlinks from parent device to its class devices.
Change USB host class device name from usbX to usb_hostX to avoid
conflict when creating aforementioned links.
Tweaked by Greg to have the symlink be "class_name:class_device_name" in
order to prevent duplicate links.
Fix for manual binding of drivers to devices. Problem is if you pass in
a valid device id, but the driver refuses to bind. Infinite loop as
write() tries to resubmit the data it just sent.
Thanks to Michal Ostrowski <mostrows@watson.ibm.com> for pointing the
problem out.
Driver for 802.11b cards using RAM-loadable Symbol firmware, such as
Symbol Wireless Networker LA4100, CompactFlash cards by Socket
Communications and Intel PRO/Wireless 2011B.
The driver implements Symbol firmware download. The rest is handled
in hermes.c and orinoco.c.
Utilities for downloading the Symbol firmware are available at
http://sourceforge.net/projects/orinoco/ Signed-off-by: Jeff Garzik <jgarzik@pobox.com>
This is a driver for Nortel emobility PCI adaptors, which consist of an
Orinoco compatible PCMCIA card and a simple PCI-to-PCMCIA bridge. The
driver initializes the device and uses Orinoco core driver for actual
wireless networking. Signed-off-by: Jeff Garzik <jgarzik@pobox.com>
It is not supported by this driver because it has no firmware in
flash. spectrum_cs is needed for this device. Signed-off-by: Jeff Garzik <jgarzik@pobox.com>
Change orinoco_translate_scan() to return error code on error.
Adjust the caller to check for errors and clean up if needed. Signed-off-by: Jeff Garzik <jgarzik@pobox.com>
mv643xx_eth_get_config_reg() was reading the wrong register.
mv643xx_eth_set_config_reg() was or'ing instead of setting the
register. These functions are trivial and both are called only from
mv643xx_eth_set_rx_mode() when changing to/from promiscuous mode.
Remove both functions and do the operations directly in
mv643xx_eth_set_rx_mode().
Also, maintain promiscuous mode setting across port resets.
Signed-off-by: Dale Farnsworth <dale@farnsworth.org> Signed-off-by: Jeff Garzik <jgarzik@pobox.com>
This patch corrects the accounting of outstanding tx skbs. It fixes
a bug that causes "Error on Queue Full" messages seen since scatter-gather
was enabled by using the hardware tcp/udp checksum generator.
Signed-off-by: Dale Farnsworth <dale@farnsworth.org> Signed-off-by: Jeff Garzik <jgarzik@pobox.com>
This patch fixes an skb memory leak under heavy receive load
(whenever the more packets have been received than the NAPI budget
allows to be processed).
Signed-off-by: Dale Farnsworth <dale@farnsworth.org> Signed-off-by: Jeff Garzik <jgarzik@pobox.com>
The sis191 is the gigabit brother of the sis190. SiS's driver suggests
that the register set is backward compatible: this should hopefully
give a basic driver.
The device should allow the usual features from a modern ethernet
adapter (802.1q, SG, Jumbo frames, TSO, checksum offload). So far
the relevant register layout is not documented. SiS's driver does
not provide these features either (at least not for Linux).
Signed-off-by: Francois Romieu <romieu@fr.zoreil.com> Signed-off-by: Jeff Garzik <jgarzik@pobox.com>
[PATCH] sis190: make 10Mbps the default when handling the StationControl register
This patch does three things:
- widen the access to the StationControl register (note the SIS_W16
versus SIS_W32 change);
- default to 10Mbps half duplex when the LPA can not be evaluated
(reg31->ctl is identical for both). It can be argued that it makes
sense as the lowest common denominator when everything else failed.
Btw it works better than the current code. :o)
- remove some enums: they do not document anymore.
Signed-off-by: Francois Romieu <romieu@fr.zoreil.com> Signed-off-by: Jeff Garzik <jgarzik@pobox.com>
[PATCH] sis190: recent chipsets from SiS include a RGMII
Extracted from SiS's GPLed driver. From the few pdf available at SiS's,
it seems that the 965 and the 966 south bridge include this interface
whereas the 965L (and anything below) does not. It is expected to be a
sis191 related feature and should not hurt the existing sis190 driver.
Signed-off-by: Francois Romieu <romieu@fr.zoreil.com> Signed-off-by: Jeff Garzik <jgarzik@pobox.com>
Peter Chubb [Sat, 3 Sep 2005 21:05:06 +0000 (14:05 -0700)]
[PATCH] 'mdio_bus_exit' in discarded section .text.exit
When building with CONFIG_PHYLIB=y on Itanium, I see:
`mdio_bus_exit' referenced in section `.init.text' of
drivers/built-in.o: defined in discarded section `.exit.text' of
drivers/built-in.o
I believe that mdio_bus_exit should not be declared __exit, because it is
referencesd from __init sections in, say, phy_init().
Signed-off-by: Peter Chubb <peterc@gelato.unsw.edu.au> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Jeff Garzik <jgarzik@pobox.com>
Adrian Bunk [Sat, 3 Sep 2005 21:04:55 +0000 (14:04 -0700)]
[PATCH] drivers/net/ne3210.c: cleanups
- make two needlessly global functions static
- kill an ancient version variable
Signed-off-by: Adrian Bunk <bunk@stusta.de> Cc: Jeff Garzik <jgarzik@pobox.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Jeff Garzik <jgarzik@pobox.com>