like for cpustat, introduce the "gtime" (guest time of the task) and
"cgtime" (guest time of the task children) fields for the
tasks. Modify signal_struct and task_struct.
Modify /proc/<pid>/stat to display these new fields.
Signed-off-by: Laurent Vivier <[email protected]>
Acked-by: Avi Kivity <[email protected]>
Signed-off-by: Ingo Molnar <[email protected]>
This patch allows you to create a new network namespace
using sys_clone, or sys_unshare.
As the network namespace is still experimental and under development
clone and unshare support is only made available when CONFIG_NET_NS is
selected at compile time.
As this patch introduces network namespace support into code paths
that exist when the CONFIG_NET is not selected there are a few
additions made to net_namespace.h to allow a few more functions
to be used when the networking stack is not compiled in.
Signed-off-by: Eric W. Biederman <[email protected]>
Signed-off-by: David S. Miller <[email protected]>
This simplifies signalfd code, by avoiding it to remain attached to the
sighand during its lifetime.
In this way, the signalfd remain attached to the sighand only during
poll(2) (and select and epoll) and read(2). This also allows to remove
all the custom "tsk == current" checks in kernel/signal.c, since
dequeue_signal() will only be called by "current".
I think this is also what Ben was suggesting time ago.
The external effect of this, is that a thread can extract only its own
private signals and the group ones. I think this is an acceptable
behaviour, in that those are the signals the thread would be able to
fetch w/out signalfd.
Signed-off-by: Davide Libenzi <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
Slab destructors were no longer supported after Christoph's
c59def9f22 change. They've been
BUGs for both slab and slub, and slob never supported them
either.
This rips out support for the dtor pointer from kmem_cache_create()
completely and fixes up every single callsite in the kernel (there were
about 224, not including the slab allocator definitions themselves,
or the documentation references).
Signed-off-by: Paul Mundt <[email protected]>
lguest does some fairly lowlevel things to support a host, which
normal modules don't need:
math_state_restore:
When the guest triggers a Device Not Available fault, we need
to be able to restore the FPU
__put_task_struct:
We need to hold a reference to another task for inter-guest
I/O, and put_task_struct() is an inline function which calls
__put_task_struct.
access_process_vm:
We need to access another task for inter-guest I/O.
map_vm_area & __get_vm_area:
We need to map the switcher shim (ie. monitor) at 0xFFC01000.
Signed-off-by: Rusty Russell <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
This patch adds an interface to set/reset flags which determines each memory
segment should be dumped or not when a core file is generated.
/proc/<pid>/coredump_filter file is provided to access the flags. You can
change the flag status for a particular process by writing to or reading from
the file.
The flag status is inherited to the child process when it is created.
Signed-off-by: Hidehiro Kawai <[email protected]>
Cc: Alan Cox <[email protected]>
Cc: David Howells <[email protected]>
Cc: Hugh Dickins <[email protected]>
Cc: Nick Piggin <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
Currently, the freezer treats all tasks as freezable, except for the kernel
threads that explicitly set the PF_NOFREEZE flag for themselves. This
approach is problematic, since it requires every kernel thread to either
set PF_NOFREEZE explicitly, or call try_to_freeze(), even if it doesn't
care for the freezing of tasks at all.
It seems better to only require the kernel threads that want to or need to
be frozen to use some freezer-related code and to remove any
freezer-related code from the other (nonfreezable) kernel threads, which is
done in this patch.
The patch causes all kernel threads to be nonfreezable by default (ie. to
have PF_NOFREEZE set by default) and introduces the set_freezable()
function that should be called by the freezable kernel threads in order to
unset PF_NOFREEZE. It also makes all of the currently freezable kernel
threads call set_freezable(), so it shouldn't cause any (intentional)
change of behaviour to appear. Additionally, it updates documentation to
describe the freezing of tasks more accurately.
[[email protected]: build fixes]
Signed-off-by: Rafael J. Wysocki <[email protected]>
Acked-by: Nigel Cunningham <[email protected]>
Cc: Pavel Machek <[email protected]>
Cc: Oleg Nesterov <[email protected]>
Cc: Gautham R Shenoy <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
This patch enables the unshare of user namespaces.
It adds a new clone flag CLONE_NEWUSER and implements copy_user_ns() which
resets the current user_struct and adds a new root user (uid == 0)
For now, unsharing the user namespace allows a process to reset its
user_struct accounting and uid 0 in the new user namespace should be contained
using appropriate means, for instance selinux
The plan, when the full support is complete (all uid checks covered), is to
keep the original user's rights in the original namespace, and let a process
become uid 0 in the new namespace, with full capabilities to the new
namespace.
Signed-off-by: Serge E. Hallyn <[email protected]>
Signed-off-by: Cedric Le Goater <[email protected]>
Acked-by: Pavel Emelianov <[email protected]>
Cc: Herbert Poetzl <[email protected]>
Cc: Kirill Korotaev <[email protected]>
Cc: Eric W. Biederman <[email protected]>
Cc: Chris Wright <[email protected]>
Cc: Stephen Smalley <[email protected]>
Cc: James Morris <[email protected]>
Cc: Andrew Morgan <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
Basically, it will allow a process to unshare its user_struct table,
resetting at the same time its own user_struct and all the associated
accounting.
A new root user (uid == 0) is added to the user namespace upon creation.
Such root users have full privileges and it seems that theses privileges
should be controlled through some means (process capabilities ?)
The unshare is not included in this patch.
Changes since [try #4]:
- Updated get_user_ns and put_user_ns to accept NULL, and
get_user_ns to return the namespace.
Changes since [try #3]:
- moved struct user_namespace to files user_namespace.{c,h}
Changes since [try #2]:
- removed struct user_namespace* argument from find_user()
Changes since [try #1]:
- removed struct user_namespace* argument from find_user()
- added a root_user per user namespace
Signed-off-by: Cedric Le Goater <[email protected]>
Signed-off-by: Serge E. Hallyn <[email protected]>
Acked-by: Pavel Emelianov <[email protected]>
Cc: Herbert Poetzl <[email protected]>
Cc: Kirill Korotaev <[email protected]>
Cc: Eric W. Biederman <[email protected]>
Cc: Chris Wright <[email protected]>
Cc: Stephen Smalley <[email protected]>
Cc: James Morris <[email protected]>
Cc: Andrew Morgan <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
Add TTY input auditing, used to audit system administrator's actions. This is
required by various security standards such as DCID 6/3 and PCI to provide
non-repudiation of administrator's actions and to allow a review of past
actions if the administrator seems to overstep their duties or if the system
becomes misconfigured for unknown reasons. These requirements do not make it
necessary to audit TTY output as well.
Compared to an user-space keylogger, this approach records TTY input using the
audit subsystem, correlated with other audit events, and it is completely
transparent to the user-space application (e.g. the console ioctls still
work).
TTY input auditing works on a higher level than auditing all system calls
within the session, which would produce an overwhelming amount of mostly
useless audit events.
Add an "audit_tty" attribute, inherited across fork (). Data read from TTYs
by process with the attribute is sent to the audit subsystem by the kernel.
The audit netlink interface is extended to allow modifying the audit_tty
attribute, and to allow sending explanatory audit events from user-space (for
example, a shell might send an event containing the final command, after the
interactive command-line editing and history expansion is performed, which
might be difficult to decipher from the TTY input alone).
Because the "audit_tty" attribute is inherited across fork (), it would be set
e.g. for sshd restarted within an audited session. To prevent this, the
audit_tty attribute is cleared when a process with no open TTY file
descriptors (e.g. after daemon startup) opens a TTY.
See https://www.redhat.com/archives/linux-audit/2007-June/msg00000.html for a
more detailed rationale document for an older version of this patch.
[[email protected]: build fix]
Signed-off-by: Miloslav Trmac <[email protected]>
Cc: Al Viro <[email protected]>
Cc: Alan Cox <[email protected]>
Cc: Paul Fulghum <[email protected]>
Cc: Casey Schaufler <[email protected]>
Cc: Steve Grubb <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
Currently try_to_freeze_tasks() has to wait until all of the vforked processes
exit and for this reason every user can make it fail. To fix this problem we
can introduce the additional process flag PF_FREEZER_SKIP to be used by tasks
that do not want to be counted as freezable by the freezer and want to have
TIF_FREEZE set nevertheless. Then, this flag can be set by tasks using
sys_vfork() before they call wait_for_completion(&vfork) and cleared after
they have woken up. After clearing it, the tasks should call try_to_freeze()
as soon as possible.
Signed-off-by: Rafael J. Wysocki <[email protected]>
Cc: Gautham R Shenoy <[email protected]>
Cc: Oleg Nesterov <[email protected]>
Cc: Pavel Machek <[email protected]>
Cc: "Eric W. Biederman" <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
This patch series implements the new signalfd() system call.
I took part of the original Linus code (and you know how badly it can be
broken :), and I added even more breakage ;) Signals are fetched from the same
signal queue used by the process, so signalfd will compete with standard
kernel delivery in dequeue_signal(). If you want to reliably fetch signals on
the signalfd file, you need to block them with sigprocmask(SIG_BLOCK). This
seems to be working fine on my Dual Opteron machine. I made a quick test
program for it:
http://www.xmailserver.org/signafd-test.c
The signalfd() system call implements signal delivery into a file descriptor
receiver. The signalfd file descriptor if created with the following API:
int signalfd(int ufd, const sigset_t *mask, size_t masksize);
The "ufd" parameter allows to change an existing signalfd sigmask, w/out going
to close/create cycle (Linus idea). Use "ufd" == -1 if you want a brand new
signalfd file.
The "mask" allows to specify the signal mask of signals that we are interested
in. The "masksize" parameter is the size of "mask".
The signalfd fd supports the poll(2) and read(2) system calls. The poll(2)
will return POLLIN when signals are available to be dequeued. As a direct
consequence of supporting the Linux poll subsystem, the signalfd fd can use
used together with epoll(2) too.
The read(2) system call will return a "struct signalfd_siginfo" structure in
the userspace supplied buffer. The return value is the number of bytes copied
in the supplied buffer, or -1 in case of error. The read(2) call can also
return 0, in case the sighand structure to which the signalfd was attached,
has been orphaned. The O_NONBLOCK flag is also supported, and read(2) will
return -EAGAIN in case no signal is available.
If the size of the buffer passed to read(2) is lower than sizeof(struct
signalfd_siginfo), -EINVAL is returned. A read from the signalfd can also
return -ERESTARTSYS in case a signal hits the process. The format of the
struct signalfd_siginfo is, and the valid fields depends of the (->code &
__SI_MASK) value, in the same way a struct siginfo would:
struct signalfd_siginfo {
__u32 signo; /* si_signo */
__s32 err; /* si_errno */
__s32 code; /* si_code */
__u32 pid; /* si_pid */
__u32 uid; /* si_uid */
__s32 fd; /* si_fd */
__u32 tid; /* si_fd */
__u32 band; /* si_band */
__u32 overrun; /* si_overrun */
__u32 trapno; /* si_trapno */
__s32 status; /* si_status */
__s32 svint; /* si_int */
__u64 svptr; /* si_ptr */
__u64 utime; /* si_utime */
__u64 stime; /* si_stime */
__u64 addr; /* si_addr */
};
[[email protected]: fix signalfd_copyinfo() on i386]
Signed-off-by: Davide Libenzi <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
Modify copy_process() to take a struct pid * parameter instead of a pid_t.
This simplifies the code a bit and also avoids having to call find_pid() to
convert the pid_t to a struct pid.
Changelog:
- Fixed Badari Pulavarty's comments and passed in &init_struct_pid
from fork_idle().
- Fixed Eric Biederman's comments and simplified this patch and
used a new patch to remove the likely(pid) check.
Signed-off-by: Sukadev Bhattiprolu <[email protected]>
Cc: Cedric Le Goater <[email protected]>
Cc: Dave Hansen <[email protected]>
Cc: Serge Hallyn <[email protected]>
Cc: Eric Biederman <[email protected]>
Cc: <[email protected]>
Acked-by: Eric W. Biederman <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
attach_pid() currently takes a pid_t and then uses find_pid() to find the
corresponding struct pid. Sometimes we already have the struct pid. We can
then skip find_pid() if attach_pid() were to take a struct pid parameter.
Signed-off-by: Sukadev Bhattiprolu <[email protected]>
Cc: Cedric Le Goater <[email protected]>
Cc: Dave Hansen <[email protected]>
Cc: Serge Hallyn <[email protected]>
Cc: <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
If CONFIG_TASK_IO_ACCOUNTING is defined, we update io accounting counters for
each task.
This patch permits reporting of values using the well known getrusage()
syscall, filling ru_inblock and ru_oublock instead of null values.
As TASK_IO_ACCOUNTING currently counts bytes counts, we approximate blocks
count doing : nr_blocks = nr_bytes / 512
Example of use :
----------------------
After patch is applied, /usr/bin/time command can now give a good
approximation of IO that the process had to do.
$ /usr/bin/time grep tototo /usr/include/*
Command exited with non-zero status 1
0.00user 0.02system 0:02.11elapsed 1%CPU (0avgtext+0avgdata 0maxresident)k
24288inputs+0outputs (0major+259minor)pagefaults 0swaps
$ /usr/bin/time dd if=/dev/zero of=/tmp/testfile count=1000
1000+0 enregistrements lus
1000+0 enregistrements écrits
512000 octets (512 kB) copiés, 0,00326601 seconde, 157 MB/s
0.00user 0.00system 0:00.00elapsed 80%CPU (0avgtext+0avgdata 0maxresident)k
0inputs+3000outputs (0major+299minor)pagefaults 0swaps
Signed-off-by: Eric Dumazet <[email protected]>
Cc: Oleg Nesterov <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
Remove includes of <linux/smp_lock.h> where it is not used/needed.
Suggested by Al Viro.
Builds cleanly on x86_64, i386, alpha, ia64, powerpc, sparc,
sparc64, and arm (all 59 defconfigs).
Signed-off-by: Randy Dunlap <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
sys_clone() and sys_unshare() both makes copies of nsproxy and its associated
namespaces. But they have different code paths.
This patch merges all the nsproxy and its associated namespace copy/clone
handling (as much as possible). Posted on container list earlier for
feedback.
- Create a new nsproxy and its associated namespaces and pass it back to
caller to attach it to right process.
- Changed all copy_*_ns() routines to return a new copy of namespace
instead of attaching it to task->nsproxy.
- Moved the CAP_SYS_ADMIN checks out of copy_*_ns() routines.
- Removed unnessary !ns checks from copy_*_ns() and added BUG_ON()
just incase.
- Get rid of all individual unshare_*_ns() routines and make use of
copy_*_ns() instead.
[[email protected]: cleanups, warning fix]
[[email protected]: remove dup_namespaces() declaration]
[[email protected]: fix CONFIG_IPC_NS=n, clone(CLONE_NEWIPC) retval]
[[email protected]: fix build with CONFIG_SYSVIPC=n]
Signed-off-by: Badari Pulavarty <[email protected]>
Signed-off-by: Serge Hallyn <[email protected]>
Cc: Cedric Le Goater <[email protected]>
Cc: "Eric W. Biederman" <[email protected]>
Cc: <[email protected]>
Signed-off-by: Cedric Le Goater <[email protected]>
Cc: Oleg Nesterov <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
I have never seen a use of SLAB_DEBUG_INITIAL. It is only supported by
SLAB.
I think its purpose was to have a callback after an object has been freed
to verify that the state is the constructor state again? The callback is
performed before each freeing of an object.
I would think that it is much easier to check the object state manually
before the free. That also places the check near the code object
manipulation of the object.
Also the SLAB_DEBUG_INITIAL callback is only performed if the kernel was
compiled with SLAB debugging on. If there would be code in a constructor
handling SLAB_DEBUG_INITIAL then it would have to be conditional on
SLAB_DEBUG otherwise it would just be dead code. But there is no such code
in the kernel. I think SLUB_DEBUG_INITIAL is too problematic to make real
use of, difficult to understand and there are easier ways to accomplish the
same effect (i.e. add debug code before kfree).
There is a related flag SLAB_CTOR_VERIFY that is frequently checked to be
clear in fs inode caches. Remove the pointless checks (they would even be
pointless without removeal of SLAB_DEBUG_INITIAL) from the fs constructors.
This is the last slab flag that SLUB did not support. Remove the check for
unimplemented flags from SLUB.
Signed-off-by: Christoph Lameter <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
Add hooks to allow a paravirt implementation to track the lifetime of
an mm. Paravirtualization requires three hooks, but only two are
needed in common code. They are:
arch_dup_mmap, which is called when a new mmap is created at fork
arch_exit_mmap, which is called when the last process reference to an
mm is dropped, which typically happens on exit and exec.
The third hook is activate_mm, which is called from the arch-specific
activate_mm() macro/function, and so doesn't need stub versions for
other architectures. It's called when an mm is first used.
Signed-off-by: Jeremy Fitzhardinge <[email protected]>
Signed-off-by: Andi Kleen <[email protected]>
Cc: [email protected]
Cc: James Bottomley <[email protected]>
Acked-by: Ingo Molnar <[email protected]>
- hrtimers did not use the hrtimer_restart enum and relied on the implict
int representation. Fix the prototypes and the functions using the enums.
- Use seperate name spaces for the enumerations
- Convert hrtimer_restart macro to inline function
- Add comments
No functional changes.
[[email protected]: fix input driver]
Signed-off-by: Thomas Gleixner <[email protected]>
Signed-off-by: Ingo Molnar <[email protected]>
Cc: john stultz <[email protected]>
Cc: Roman Zippel <[email protected]>
Cc: Dmitry Torokhov <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
Of kernel subsystems that work with pids the tty layer is probably the largest
consumer. But it has the nice virtue that the assiation with a session only
lasts until the session leader exits. Which means that no reference counting
is required. So using struct pid winds up being a simple optimization to
avoid hash table lookups.
In the long term the use of pid_nr also ensures that when we have multiple pid
spaces mixed everything will work correctly.
Signed-off-by: Eric W. Biederman <[email protected]>
Cc: Alan Cox <[email protected]>
Cc: Oleg Nesterov <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
They are fat: 4x8 bytes in task_struct.
They are uncoditionally updated in every fork, read, write and sendfile.
They are used only if you have some "extended acct fields feature".
And please, please, please, read(2) knows about bytes, not characters,
why it is called "rchar"?
Signed-off-by: Alexey Dobriyan <[email protected]>
Cc: Jay Lan <[email protected]>
Cc: Balbir Singh <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
This reverts commit 7a238fcba0 in
preparation for a better and simpler fix proposed by Eric Biederman
(and fixed up by Serge Hallyn)
Acked-by: Serge E. Hallyn <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
Fix exit race by splitting the nsproxy putting into two pieces. First
piece reduces the nsproxy refcount. If we dropped the last reference, then
it puts the mnt_ns, and returns the nsproxy as a hint to the caller. Else
it returns NULL. The second piece of exiting task namespaces sets
tsk->nsproxy to NULL, and drops the references to other namespaces and
frees the nsproxy only if an nsproxy was passed in.
A little awkward and should probably be reworked, but hopefully it fixes
the NFS oops.
Signed-off-by: Serge E. Hallyn <[email protected]>
Cc: Herbert Poetzl <[email protected]>
Cc: Oleg Nesterov <[email protected]>
Cc: "Eric W. Biederman" <[email protected]>
Cc: Cedric Le Goater <[email protected]>
Cc: Daniel Hokka Zakrisson <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
Virtually index, physically tagged cache architectures can get away
without cache flushing when forking. This patch adds a new cache
flushing function flush_cache_dup_mm(struct mm_struct *) which for the
moment I've implemented to do the same thing on all architectures
except on MIPS where it's a no-op.
Signed-off-by: Ralf Baechle <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
An fdtable can either be embedded inside a files_struct or standalone (after
being expanded). When an fdtable is being discarded after all RCU references
to it have expired, we must either free it directly, in the standalone case,
or free the files_struct it is contained within, in the embedded case.
Currently the free_files field controls this behavior, but we can get rid of
it entirely, as all the necessary information is already recorded. We can
distinguish embedded and standalone fdtables using max_fds, and if it is
embedded we can divine the relevant files_struct using container_of().
Signed-off-by: Vadim Lobanov <[email protected]>
Cc: Christoph Hellwig <[email protected]>
Cc: Al Viro <[email protected]>
Cc: Dipankar Sarma <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
Currently, each fdtable supports three dynamically-sized arrays of data: the
fdarray and two fdsets. The code allows the number of fds supported by the
fdarray (fdtable->max_fds) to differ from the number of fds supported by each
of the fdsets (fdtable->max_fdset).
In practice, it is wasteful for these two sizes to differ: whenever we hit a
limit on the smaller-capacity structure, we will reallocate the entire fdtable
and all the dynamic arrays within it, so any delta in the memory used by the
larger-capacity structure will never be touched at all.
Rather than hogging this excess, we shouldn't even allocate it in the first
place, and keep the capacities of the fdarray and the fdsets equal. This
patch removes fdtable->max_fdset. As an added bonus, most of the supporting
code becomes simpler.
Signed-off-by: Vadim Lobanov <[email protected]>
Cc: Christoph Hellwig <[email protected]>
Cc: Al Viro <[email protected]>
Cc: Dipankar Sarma <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
The dup_fd() function creates a new files_struct and fdtable embedded inside
that files_struct, and then possibly expands the fdtable using expand_files().
The out_release error path is invoked when expand_files() returns an error
code. However, when this attempt to expand fails, the fdtable is left in its
original embedded form, so it is pointless to try to free the associated
fdarray and fdsets.
Signed-off-by: Vadim Lobanov <[email protected]>
Cc: Dipankar Sarma <[email protected]>
Cc: Christoph Hellwig <[email protected]>
Cc: Al Viro <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
The present per-task IO accounting isn't very useful. It simply counts the
number of bytes passed into read() and write(). So if a process reads 1MB
from an already-cached file, it is accused of having performed 1MB of I/O,
which is wrong.
(David Wright had some comments on the applicability of the present logical IO accounting:
For billing purposes it is useless but for workload analysis it is very
useful
read_bytes/read_calls average read request size
write_bytes/write_calls average write request size
read_bytes/read_blocks ie logical/physical can indicate hit rate or thrashing
write_bytes/write_blocks ie logical/physical guess since pdflush writes can
be missed
I often look for logical larger than physical to see filesystem cache
problems. And the bytes/cpusec can help find applications that are
dominating the cache and causing slow interactive response from page cache
contention.
I want to find the IO intensive applications and make sure they are doing
efficient IO. Thus the acctcms(sysV) or csacms command would give the high
IO commands).
This patchset adds new accounting which tries to be more accurate. We account
for three things:
reads:
attempt to count the number of bytes which this process really did cause
to be fetched from the storage layer. Done at the submit_bio() level, so it
is accurate for block-backed filesystems. I also attempt to wire up NFS and
CIFS.
writes:
attempt to count the number of bytes which this process caused to be sent
to the storage layer. This is done at page-dirtying time.
The big inaccuracy here is truncate. If a process writes 1MB to a file
and then deletes the file, it will in fact perform no writeout. But it will
have been accounted as having caused 1MB of write.
So...
cancelled_writes:
account the number of bytes which this process caused to not happen, by
truncating pagecache.
We _could_ just subtract this from the process's `write' accounting. But
that means that some processes would be reported to have done negative
amounts of write IO, which is silly.
So we just report the raw number and punt this decision up to userspace.
Now, we _could_ account for writes at the physical I/O level. But
- This would require that we track memory-dirtying tasks at the per-page
level (would require a new pointer in struct page).
- It would mean that IO statistics for a process are usually only available
long after that process has exitted. Which means that we probably cannot
communicate this info via taskstats.
This patch:
Wire up the kernel-private data structures and the accessor functions to
manipulate them.
Cc: Jay Lan <[email protected]>
Cc: Shailabh Nagar <[email protected]>
Cc: Balbir Singh <[email protected]>
Cc: Chris Sturtivant <[email protected]>
Cc: Tony Ernst <[email protected]>
Cc: Guillaume Thouvenin <[email protected]>
Cc: David Wright <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
Rename 'struct namespace' to 'struct mnt_namespace' to avoid confusion with
other namespaces being developped for the containers : pid, uts, ipc, etc.
'namespace' variables and attributes are also renamed to 'mnt_ns'
Signed-off-by: Kirill Korotaev <[email protected]>
Signed-off-by: Cedric Le Goater <[email protected]>
Cc: Eric W. Biederman <[email protected]>
Cc: Herbert Poetzl <[email protected]>
Cc: Sukadev Bhattiprolu <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
Change all the uses of f_{dentry,vfsmnt} to f_path.{dentry,mnt} in
linux/kernel/.
Signed-off-by: Josef "Jeff" Sipek <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
sys_unshare(CLONE_SIGHAND) is broken, the code under 'if (new_sigh)' is
never executed but very wrong. Just remove it to avoid a confusion,
task_lock() has nothing to do with ->sighand changing.
Also, change the comment in unshare_sighand(). Yes, CLONE_THREAD implies
CLONE_SIGHAND, but still it looks confusing. Also, we don't need to check
current->sighand != NULL.
Signed-off-by: Oleg Nesterov <[email protected]>
Acked-by: Peter Zijlstra <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
Allocate ->signal->stats on demand in taskstats_exit(), this allows us to
remove taskstats_tgid_alloc() (the last non-trivial inline) from taskstat's
public interface.
Signed-off-by: Oleg Nesterov <[email protected]>
Cc: Balbir Singh <[email protected]>
Cc: Shailabh Nagar <[email protected]>
Cc: Jay Lan <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
The CLONE_CHILD_CLEARTID flag is used by NPTL to have its threads
communicate via memory/futex when they exit, so pthread_join can
synchronize using a simple futex wait. The word of user memory where NPTL
stores a thread's own TID is what it passes; this gets reset to zero at
thread exit.
It is not desireable to touch this user memory when threads are dying due
to a fatal signal. A core dump is more usefully representative of the
dying program state if the threads live at the time of the crash have their
NPTL data structures unperturbed. The userland expectation of
CLONE_CHILD_CLEARTID has only ever been that it works for a thread making
an _exit system call.
This problem was identified by Ernie Petrides <[email protected]>.
Signed-off-by: Roland McGrath <[email protected]>
Cc: Ernie Petrides <[email protected]>
Cc: Jakub Jelinek <[email protected]>
Acked-by: Ingo Molnar <[email protected]>
Cc: Ulrich Drepper <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
Replace all uses of kmem_cache_t with struct kmem_cache.
The patch was generated using the following script:
#!/bin/sh
#
# Replace one string by another in all the kernel sources.
#
set -e
for file in `find * -name "*.c" -o -name "*.h"|xargs grep -l $1`; do
quilt add $file
sed -e "1,\$s/$1/$2/g" $file >/tmp/$$
mv /tmp/$$ $file
quilt refresh
done
The script was run like this
sh replace kmem_cache_t "struct kmem_cache"
Signed-off-by: Christoph Lameter <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
The new swap token patches replace the current token traversal algo. The old
algo had a crude timeout parameter that was used to handover the token from
one task to another. This algo, transfers the token to the tasks that are in
need of the token. The urgency for the token is based on the number of times
a task is required to swap-in pages. Accordingly, the priority of a task is
incremented if it has been badly affected due to swap-outs. To ensure that
the token doesnt bounce around rapidly, the token holders are given a priority
boost. The priority of tasks is also decremented, if their rate of swap-in's
keeps reducing. This way, the condition to check whether to pre-empt the swap
token, is a matter of comparing two task's priority fields.
[[email protected]: cleanups]
Signed-off-by: Ashwin Chaugule <[email protected]>
Cc: Rik van Riel <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
This patch is the meat of the PDA change. This patch makes several related
changes:
1: Most significantly, %gs is now used in the kernel. This means that on
entry, the old value of %gs is saved away, and it is reloaded with
__KERNEL_PDA.
2: entry.S constructs the stack in the shape of struct pt_regs, and this
is passed around the kernel so that the process's saved register
state can be accessed.
Unfortunately struct pt_regs doesn't currently have space for %gs
(or %fs). This patch extends pt_regs to add space for gs (no space
is allocated for %fs, since it won't be used, and it would just
complicate the code in entry.S to work around the space).
3: Because %gs is now saved on the stack like %ds, %es and the integer
registers, there are a number of places where it no longer needs to
be handled specially; namely context switch, and saving/restoring the
register state in a signal context.
4: And since kernel threads run in kernel space and call normal kernel
code, they need to be created with their %gs == __KERNEL_PDA.
Signed-off-by: Jeremy Fitzhardinge <[email protected]>
Signed-off-by: Andi Kleen <[email protected]>
Cc: Chuck Ebbert <[email protected]>
Cc: Zachary Amsden <[email protected]>
Cc: Jan Beulich <[email protected]>
Cc: Andi Kleen <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
The return value of copy_process() should be checked by IS_ERR().
Signed-off-by: Akinobu Mita <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
Laurent Vivier