dev_alloc_skb is designated for RX descriptors, not TX. (Some drivers
use it for the latter anyway, but that's a different story)
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
skbuff.h has an #ifndef CONFIG_HAVE_ARCH_DEV_ALLOC_SKB to allow
architectures to reimplement __dev_alloc_skb. It's not set on any
architecture and now that we have an architecture-overrideable
NET_SKB_PAD there is not point at all to have one either.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
The CPU hotplug locking was quite messy, with a recursive lock to
handle the fact that both the actual up/down sequence wanted to
protect itself from being re-entered, but the callbacks that it
called also tended to want to protect themselves from CPU events.
This splits the lock into two (one to serialize the whole hotplug
sequence, the other to protect against the CPU present bitmaps
changing). The latter still allows recursive usage because some
subsystems (ondemand policy for cpufreq at least) had already gotten
too used to the lax locking, but the locking mistakes are hopefully
now less fundamental, and we now warn about recursive lock usage
when we see it, in the hope that it can be fixed.
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6:
[VLAN]: __vlan_hwaccel_rx can use the faster ether_compare_addr
[PKT_SCHED] HTB: initialize upper bound properly
[IPV4]: Clear skb cb on IP input
[NET]: Update frag_list in pskb_trim
On systems with a large number of cpus, with even a modest rate of tasks
exiting per cpu, the volume of taskstats data sent on thread exit can
overflow a userspace listener's buffers.
One approach to avoiding overflow is to allow listeners to get data for a
limited and specific set of cpus. By scaling the number of listeners
and/or the cpus they monitor, userspace can handle the statistical data
overload more gracefully.
In this patch, each listener registers to listen to a specific set of cpus
by specifying a cpumask. The interest is recorded per-cpu. When a task
exits on a cpu, its taskstats data is unicast to each listener interested
in that cpu.
Thanks to Andrew Morton for pointing out the various scalability and
general concerns of previous attempts and for suggesting this design.
[akpm@osdl.org: build fix]
Signed-off-by: Shailabh Nagar <nagar@watson.ibm.com>
Signed-off-by: Balbir Singh <balbir@in.ibm.com>
Signed-off-by: Chandra Seetharaman <sekharan@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Don't send taskstats (per-pid or per-tgid) on thread exit when no one is
listening for such data.
Currently the taskstats interface allocates a structure, fills it in and
calls netlink to send out per-pid and per-tgid stats regardless of whether
a userspace listener for the data exists (netlink layer would check for
that and avoid the multicast).
As a result of this patch, the check for the no-listener case is performed
early, avoiding the redundant allocation and filling up of the taskstats
structures.
Signed-off-by: Balbir Singh <balbir@in.ibm.com>
Signed-off-by: Shailabh Nagar <nagar@watson.ibm.com>
Cc: Jay Lan <jlan@engr.sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Send per-tgid data only once during exit of a thread group instead of once
with each member thread exit.
Currently, when a thread exits, besides its per-tid data, the per-tgid data
of its thread group is also sent out, if its thread group is non-empty.
The per-tgid data sent consists of the sum of per-tid stats for all
*remaining* threads of the thread group.
This patch modifies this sending in two ways:
- the per-tgid data is sent only when the last thread of a thread group
exits. This cuts down heavily on the overhead of sending/receiving
per-tgid data, especially when other exploiters of the taskstats
interface aren't interested in per-tgid stats
- the semantics of the per-tgid data sent are changed. Instead of being
the sum of per-tid data for remaining threads, the value now sent is the
true total accumalated statistics for all threads that are/were part of
the thread group.
The patch also addresses a minor issue where failure of one accounting
subsystem to fill in the taskstats structure was causing the send of
taskstats to not be sent at all.
The patch has been tested for stability and run cerberus for over 4 hours
on an SMP.
[akpm@osdl.org: bugfixes]
Signed-off-by: Shailabh Nagar <nagar@watson.ibm.com>
Signed-off-by: Balbir Singh <balbir@in.ibm.com>
Cc: Jay Lan <jlan@engr.sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Export I/O delays seen by a task through /proc/<tgid>/stats for use in top
etc.
Note that delays for I/O done for swapping in pages (swapin I/O) is clubbed
together with all other I/O here (this is not the case in the netlink
interface where the swapin I/O is kept distinct)
[akpm@osdl.org: printk warning fix]
Signed-off-by: Shailabh Nagar <nagar@watson.ibm.com>
Signed-off-by: Balbir Singh <balbir@in.ibm.com>
Cc: Jes Sorensen <jes@sgi.com>
Cc: Peter Chubb <peterc@gelato.unsw.edu.au>
Cc: Erich Focht <efocht@ess.nec.de>
Cc: Levent Serinol <lserinol@gmail.com>
Cc: Jay Lan <jlan@engr.sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Create a "taskstats" interface based on generic netlink (NETLINK_GENERIC
family), for getting statistics of tasks and thread groups during their
lifetime and when they exit. The interface is intended for use by multiple
accounting packages though it is being created in the context of delay
accounting.
This patch creates the interface without populating the fields of the data
that is sent to the user in response to a command or upon the exit of a task.
Each accounting package interested in using taskstats has to provide an
additional patch to add its stats to the common structure.
[akpm@osdl.org: cleanups, Kconfig fix]
Signed-off-by: Shailabh Nagar <nagar@us.ibm.com>
Signed-off-by: Balbir Singh <balbir@in.ibm.com>
Cc: Jes Sorensen <jes@sgi.com>
Cc: Peter Chubb <peterc@gelato.unsw.edu.au>
Cc: Erich Focht <efocht@ess.nec.de>
Cc: Levent Serinol <lserinol@gmail.com>
Cc: Jay Lan <jlan@engr.sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Unlike earlier iterations of the delay accounting patches, now delays are only
collected for the actual I/O waits rather than try and cover the delays seen
in I/O submission paths.
Account separately for block I/O delays incurred as a result of swapin page
faults whose frequency can be affected by the task/process' rss limit. Hence
swapin delays can act as feedback for rss limit changes independent of I/O
priority changes.
Signed-off-by: Shailabh Nagar <nagar@watson.ibm.com>
Signed-off-by: Balbir Singh <balbir@in.ibm.com>
Cc: Jes Sorensen <jes@sgi.com>
Cc: Peter Chubb <peterc@gelato.unsw.edu.au>
Cc: Erich Focht <efocht@ess.nec.de>
Cc: Levent Serinol <lserinol@gmail.com>
Cc: Jay Lan <jlan@engr.sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Initialization code related to collection of per-task "delay" statistics which
measure how long it had to wait for cpu, sync block io, swapping etc. The
collection of statistics and the interface are in other patches. This patch
sets up the data structures and allows the statistics collection to be
disabled through a kernel boot parameter.
Signed-off-by: Shailabh Nagar <nagar@watson.ibm.com>
Signed-off-by: Balbir Singh <balbir@in.ibm.com>
Cc: Jes Sorensen <jes@sgi.com>
Cc: Peter Chubb <peterc@gelato.unsw.edu.au>
Cc: Erich Focht <efocht@ess.nec.de>
Cc: Levent Serinol <lserinol@gmail.com>
Cc: Jay Lan <jlan@engr.sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Add another list utility function to check for last element in a list.
Signed-off-by: Shailabh Nagar <nagar@watson.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
It's way past time to bump it to 8. Everyone had been warned - for
months now.
RH kernels have had this for more than a year.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
drops gpio_set_high, gpio_set_low from the nsc_gpio_ops vtable. While we
can't drop them from scx200_gpio (or can we?), we dont need them for new users
of the exported vtable; gpio_set(1), gpio_set(0) work fine.
Signed-off-by: Jim Cromie <jim.cromie@gmail.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Got a customer bug report (https://bugzilla.novell.com/190296) about kernel
symbols longer than 127 characters which end up in a string buffer that is
not NULL terminated, leading to garbage in /proc/kallsyms. Using strlcpy
prevents this from happening, even though such symbols still won't come out
right.
A better fix would be to not use a fixed-size buffer, but it's probably not
worth the trouble. (Modversion'ed symbols even have a length limit of 60.)
[bunk@stusta.de: build fix]
Signed-off-by: Andreas Gruenbacher <agruen@suse.de>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
__vunmap must not rely on area->nr_pages when picking the release methode
for area->pages. It may be too small when __vmalloc_area_node failed early
due to lacking memory. Instead, use a flag in vmstruct to differentiate.
Signed-off-by: Jan Kiszka <jan.kiszka@web.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
The inline function compare_ether_addr is faster than memcmp.
Also, don't need to drag in proc_fs.h, the only reference to proc_dir_entry
is a pointer so the declaration is needed here.
Signed-off-by: Stephen Hemminger <shemminger@osdl.org>
Acked-by: Ben Greear <greearb@candelatech.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
As a result of 894673ee61, the ARM
architecture is more or less unbuildable - only one defconfig appears
to build, with all others erroring out with:
CC arch/arm/kernel/setup.o
In file included from /home/rmk/git/linux-2.6-rmk/arch/arm/kernel/setup.c:22:
/home/rmk/git/linux-2.6-rmk/include/linux/root_dev.h:7: warning: implicit declaration of function `MKDEV'
...
Essentially, root_dev.h uses MKDEV and dev_t, but does not include any
headers which provide either of these definitions. The reason it worked
previously is that linux/tty.h just happened to include the required
headers for linux/root_dev.h.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* HEAD:
[NET]: fix __sk_stream_mem_reclaim
[Bluetooth] Fix deadlock in the L2CAP layer
[Bluetooth] Let BT_HIDP depend on INPUT
[Bluetooth] Avoid NULL pointer dereference with tty->driver
[Bluetooth] Remaining transitions to use kzalloc()
[WAN]: converting generic HDLC to use netif_dormant*()
[IPV4]: Fix error handling for fib_insert_node call
[NETROM] lockdep: fix false positive
[ROSE] lockdep: fix false positive
[AX.25]: Optimize AX.25 socket list lock
[IPCOMP]: Fix truesize after decompression
[IPV6]: Use ipv6_addr_src_scope for link address sorting.
[TCP] tcp_highspeed: Fix AI updates.
[MAINTAINERS]: Add proper entry for TC classifier
[NETROM]: Drop lock before calling nr_destroy_socket
[NETROM]: Fix locking order when establishing a NETROM circuit.
[AX.25]: Fix locking of ax25 protocol function list.
[IPV6]: order addresses by scope
