linux-toradex.git/drivers/oprofile/oprof.c, branch v3.2.68

oprofile: Fix crash when unloading module (hr timer mode)

2011-11-04T14:04:33+00:00

Oprofile may crash in a KVM guest while unlaoding modules. This
happens if oprofile_arch_init() fails and oprofile switches to the hr
timer mode as a fallback. In this case oprofile_arch_exit() is called,
but it never was initialized properly which causes the crash. This
patch fixes this.

oprofile: using timer interrupt.
BUG: unable to handle kernel NULL pointer dereference at 0000000000000008
IP: [] unregister_syscore_ops+0x41/0x58
PGD 41da3f067 PUD 41d80e067 PMD 0
Oops: 0002 [#1] PREEMPT SMP
CPU 5
Modules linked in: oprofile(-)

Pid: 2382, comm: modprobe Not tainted 3.1.0-rc7-00018-g709a39d #18 Advanced Micro Device Anaheim/Anaheim
RIP: 0010:[]  [] unregister_syscore_ops+0x41/0x58
RSP: 0018:ffff88041de1de98  EFLAGS: 00010296
RAX: 0000000000000000 RBX: ffffffffa00060e0 RCX: dead000000200200
RDX: 0000000000000000 RSI: dead000000100100 RDI: ffffffff8178c620
RBP: ffff88041de1dea8 R08: 0000000000000001 R09: 0000000000000082
R10: 0000000000000000 R11: ffff88041de1dde8 R12: 0000000000000080
R13: fffffffffffffff5 R14: 0000000000000001 R15: 0000000000610210
FS:  00007f9ae5bef700(0000) GS:ffff88042fd40000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 000000008005003b
CR2: 0000000000000008 CR3: 000000041ca44000 CR4: 00000000000006e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Process modprobe (pid: 2382, threadinfo ffff88041de1c000, task ffff88042db6d040)
Stack:
 ffff88041de1deb8 ffffffffa0006770 ffff88041de1deb8 ffffffffa000251e
 ffff88041de1dec8 ffffffffa00022c2 ffff88041de1ded8 ffffffffa0004993
 ffff88041de1df78 ffffffff81073115 656c69666f72706f 0000000000610200
Call Trace:
 [] op_nmi_exit+0x15/0x17 [oprofile]
 [] oprofile_arch_exit+0xe/0x10 [oprofile]
 [] oprofile_exit+0x13/0x15 [oprofile]
 [] sys_delete_module+0x1c3/0x22f
 [] ? trace_hardirqs_on_thunk+0x3a/0x3f
 [] system_call_fastpath+0x16/0x1b
Code: 20 c6 78 81 e8 c5 cc 23 00 48 8b 13 48 8b 43 08 48 be 00 01 10 00 00 00 ad de 48 b9 00 02 20 00 00 00 ad de 48 c7 c7 20 c6 78 81
 89 42 08 48 89 10 48 89 33 48 89 4b 08 e8 a6 c0 23 00 5a 5b
RIP  [] unregister_syscore_ops+0x41/0x58
 RSP 
CR2: 0000000000000008
---[ end trace 06d4e95b6aa3b437 ]---

CC: stable@kernel.org # 2.6.37+
Signed-off-by: Robert Richter

oprofile: Use linux/mutex.h

2011-05-24T10:45:59+00:00

The oprofile code is still including asm/mutex.h instead of
linux/mutex.h.

Signed-off-by: Anton Blanchard 
Signed-off-by: Robert Richter

oprofile: disable write access to oprofilefs while profiler is running

2010-10-12T15:25:06+00:00

Oprofile counters are setup when profiling is disabled. Thus, writing
to oprofilefs has no immediate effect. Changes are updated only after
oprofile is reenabled.

To keep userland and kernel states synchronized, we now allow
configuration of oprofile only if profiling is disabled.  In this case
it checks if the profiler is running and then disables write access to
oprofilefs by returning -EBUSY. The change should be backward
compatible with current oprofile userland daemon.

Acked-by: Maynard Johnson 
Cc: William Cohen 
Cc: Suravee Suthikulpanit 
Signed-off-by: Robert Richter

oprofile: don't call arch exit code from init code on failure

2010-08-31T09:47:50+00:00

oprofile_init calls oprofile_arch_init to initialise the architecture-specific
backend code. If this backend code returns failure, oprofile_arch_exit is
called immediately, making it difficult to allocate and free resources
correctly.

This patch removes the oprofile_arch_exit call from oprofile_init,
meaning that all architectures must ensure that oprofile_arch_init
cleans up any mess it's made before returning an error. As far as
I can tell, this only affects the code for ARM.

Cc: Robert Richter 
Cc: Matt Fleming 
Cc: Peter Zijlstra 
Cc: Ingo Molnar 
Signed-off-by: Will Deacon 
Signed-off-by: Robert Richter

oprofile: convert oprofile from timer_hook to hrtimer

2010-03-02T16:03:20+00:00

Oprofile is currently broken on systems running with NOHZ enabled.
A maximum of 1 tick is accounted via the timer_hook if a cpu sleeps
for a longer period of time. This does bad things to the percentages
in the profiler output. To solve this problem convert oprofile to
use a restarting hrtimer instead of the timer_hook.

Signed-off-by: Martin Schwidefsky 
Signed-off-by: Robert Richter

oprofile: Adding switch counter to oprofile statistic variables

2009-07-20T14:43:21+00:00

This patch moves the multiplexing switch counter from x86 code to
common oprofile statistic variables. Now the value will be available
and usable for all architectures. The initialization and
incrementation also moved to common code.

Signed-off-by: Robert Richter

oprofile: Grouping multiplexing code in oprof.c

2009-07-20T14:43:19+00:00

This patch moves multiplexing code to a single section of code. This
reduces the use of #ifdefs especially within functions.

Signed-off-by: Robert Richter

oprofile: Remove oprofile_multiplexing_init()

2009-07-20T14:43:19+00:00

oprofile_multiplexing_init() can be removed when moving the
initialization of oprofile_time_slice to oprofile_create_files().

Signed-off-by: Robert Richter

oprofile: Rename variable timeout_jiffies and move to oprofile_files.c

2009-07-20T14:43:19+00:00

This patch renames timeout_jiffies into an oprofile specific name. The
macro MULTIPLEXING_TIMER_DEFAULT is changed too.

Also, since this variable is controlled using oprofilefs, its
definition is moved to oprofile_files.c.

Signed-off-by: Robert Richter

oprofile: oprofile_set_timeout(), return with error for invalid args

2009-07-20T14:43:18+00:00

Return with -EINVAL for invalid parameters instead of setting the
default value in oprofile_set_timeout().

Signed-off-by: Robert Richter