It has been suggested that I add a way to disable the function tracer
on an oops. This code adds a ftrace_kill_atomic. It is not meant to be
used in normal situations. It will disable the ftrace tracer, but will
not perform the nice shutdown that requires scheduling.
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Cc: Steven Rostedt <srostedt@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This is more of a clean up. Currently the function tracer initializes the
tracer with which ever CPU was last used for tracing. This value isn't
realy useful for function tracing, but at least it should be something other
than a random number.
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Cc: Steven Rostedt <srostedt@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
We have two markers now that are enabled on sched_switch. One that records
the context switching and the other that records task wake ups. Currently
we enable the tracing first and then set the markers. This causes some
confusing traces:
# tracer: sched_switch
#
# TASK-PID CPU# TIMESTAMP FUNCTION
# | | | | |
trace-cmd-3973 [00] 115.834817: 3973:120:R + 3: 0:S
trace-cmd-3973 [01] 115.834910: 3973:120:R + 6: 0:S
trace-cmd-3973 [02] 115.834910: 3973:120:R + 9: 0:S
trace-cmd-3973 [03] 115.834910: 3973:120:R + 12: 0:S
trace-cmd-3973 [02] 115.834910: 3973:120:R + 9: 0:S
<idle>-0 [02] 115.834910: 0:140:R ==> 3973:120:R
Here we see that trace-cmd with PID 3973 wakes up task 9 but the next line
shows the idle task doing a context switch to task 3973.
Enabling the tracing to _after_ the markers are set creates a much saner
output:
# tracer: sched_switch
#
# TASK-PID CPU# TIMESTAMP FUNCTION
# | | | | |
<idle>-0 [02] 7922.634225: 0:140:R ==> 4790:120:R
trace-cmd-4789 [03] 7922.634225: 0:140:R + 4790:120:R
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Cc: Steven Rostedt <srostedt@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Alexander Beregalov reported this build failure:
$ make CROSS_COMPILE=sparc64-unknown-linux-gnu- image modules && sudo
make modules_install
CHK include/linux/version.h
CHK include/linux/utsrelease.h
CALL scripts/checksyscalls.sh
CHK include/linux/compile.h
dnsdomainname: Unknown host
CC arch/sparc64/kernel/sparc64_ksyms.o
arch/sparc64/kernel/sparc64_ksyms.c:116: error: '_mcount' undeclared
here (not in a function)
cc1: warnings being treated as errors
arch/sparc64/kernel/sparc64_ksyms.c:116: error: type defaults to 'int'
in declaration of '_mcount'
And bisected it back to:
| commit 395a59d0f8
| Author: Abhishek Sagar <sagar.abhishek@gmail.com>
| Date: Sat Jun 21 23:47:27 2008 +0530
|
| ftrace: store mcount address in rec->ip
the mcount prototype is only available under CONFIG_FTRACE,
extend it to CONFIG_MCOUNT as well.
Reported-and-bisected-by: Alexander Beregalov <a.beregalov@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
The moment mmiotrace is enabled, I hit a NULL deref in:
IP: [<ffffffff80256e71>] __trace_special+0x17c/0x23a
Call Trace:
[<ffffffff802573cc>] ftrace_special+0x6f/0x9a
[<ffffffff8023e3e4>] down+0x19/0x4a
[<ffffffff80228adc>] acquire_console_sem+0x42/0x58
[<ffffffff8035d273>] con_flush_chars+0x28/0x43
[<ffffffff80354a70>] write_chan+0x22e/0x334
[<ffffffff802244e9>] ? default_wake_function+0x0/0xf
[<ffffffff8035236d>] tty_write+0x195/0x228
[<ffffffff80354842>] ? write_chan+0x0/0x334
[<ffffffff8027c23a>] vfs_write+0xae/0x137
[<ffffffff8027c6e3>] sys_write+0x47/0x70
[<ffffffff8020b1db>] system_call_after_swapgs+0x7b/0x80
which means 'entry' in __trace_special() is NULL.
[ mingo@elte.hu: that ftrace_special() was a leftover. ]
Signed-off-by: Pekka Paalanen <pq@iki.fi>
Cc: Steven Rostedt <srostedt@redhat.com>
Cc: proski@gnu.org
Cc: "Vegard Nossum" <vegard.nossum@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
* 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/aegl/linux-2.6:
[IA64] Eliminate NULL test after alloc_bootmem in iosapic_alloc_rte()
[IA64] Handle count==0 in sn2_ptc_proc_write()
[IA64] Fix boot failure on ia64/sn2
* 'kvm-updates-2.6.26' of git://git.kernel.org/pub/scm/linux/kernel/git/avi/kvm:
KVM: Remove now unused structs from kvm_para.h
x86: KVM guest: Use the paravirt clocksource structs and functions
KVM: Make kvm host use the paravirt clocksource structs
x86: Make xen use the paravirt clocksource structs and functions
x86: Add structs and functions for paravirt clocksource
KVM: VMX: Fix host msr corruption with preemption enabled
KVM: ioapic: fix lost interrupt when changing a device's irq
KVM: MMU: Fix oops on guest userspace access to guest pagetable
KVM: MMU: large page update_pte issue with non-PAE 32-bit guests (resend)
KVM: MMU: Fix rmap_write_protect() hugepage iteration bug
KVM: close timer injection race window in __vcpu_run
KVM: Fix race between timer migration and vcpu migration
On 9xx chips, bus mastering needs to be enabled at resume time for much of the
chip to function. With this patch, vblank interrupts will work as expected
on resume, along with other chip functions. Fixes kernel bugzilla #10844.
Signed-off-by: Jie Luo <clotho67@gmail.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The kvm_* structs are obsoleted by the pvclock_* ones.
Now all users have been switched over and the old structs
can be dropped.
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
This patch updates the kvm host code to use the pvclock structs
and functions, thereby making it compatible with Xen.
The patch also fixes an initialization bug: on SMP systems the
per-cpu has two different locations early at boot and after CPU
bringup. kvmclock must take that in account when registering the
physical address within the host.
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
This patch updates the kvm host code to use the pvclock structs.
It also makes the paravirt clock compatible with Xen.
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
This patch adds structs for the paravirt clocksource ABI
used by both xen and kvm (pvclock-abi.h).
It also adds some helper functions to read system time and
wall clock time from a paravirtual clocksource (pvclock.[ch]).
They are based on the xen code. They are enabled using
CONFIG_PARAVIRT_CLOCK.
Subsequent patches of this series will put the code in use.
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Acked-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
This patch fixes bz 450641.
This patch changes the computation for zero_metapath_length(), which it
renames to metapath_branch_start(). When you are extending the metadata
tree, The indirect blocks that point to the new data block must either
diverge from the existing tree either at the inode, or at the first
indirect block. They can diverge at the first indirect block because the
inode has room for 483 pointers while the indirect blocks have room for
509 pointers, so when the tree is grown, there is some free space in the
first indirect block. What metapath_branch_start() now computes is the
height where the first indirect block for the new data block is located.
It can either be 1 (if the indirect block diverges from the inode) or 2
(if it diverges from the first indirect block).
Signed-off-by: Benjamin Marzinski <bmarzins@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
Steven Rostedt
Abhishek Sagar
Ingo Molnar
Pekka Paalanen
Linus Torvalds
Jie Luo
Gerd Hoffmann
Benjamin Marzinski