handle_signal()->set_fs() has a nice comment which explains what
set_fs() is, but it doesn't explain why it is needed and why it
depends on CONFIG_X86_64.
Afaics, the history of this confusion is:
1. I guess today nobody can explain why it was needed
in arch/i386/kernel/signal.c, perhaps it was always
wrong. This predates 2.4.0 kernel.
2. then it was copy-and-past'ed to the new x86_64 arch.
3. then it was removed from i386 (but not from x86_64)
by b93b6ca3 "i386: remove unnecessary code".
4. then it was reintroduced under CONFIG_X86_64 when x86
unified i386 and x86_64, because the patch above didn't
touch x86_64.
Remove it. ->addr_limit should be correct. Even if it was possible
that it is wrong, it is too late to fix it after setup_rt_frame().
Linus commented in:
http://lkml.kernel.org/r/alpine.LFD.0.999.0707170902570.19166@woody.linux-foundation.org
... about the equivalent bit from i386:
Heh. I think it's entirely historical.
Please realize that the whole reason that function is called "set_fs()" is
that it literally used to set the %fs segment register, not
"->addr_limit".
So I think the "set_fs(USER_DS)" is there _only_ to match the other
regs->xds = __USER_DS;
regs->xes = __USER_DS;
regs->xss = __USER_DS;
regs->xcs = __USER_CS;
things, and never mattered. And now it matters even less, and has been
copied to all other architectures where it is just totally insane.
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Link: http://lkml.kernel.org/r/20110710164424.GA20261@redhat.com
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
1. do_signal() looks at TS_RESTORE_SIGMASK and calculates the
mask which should be stored in the signal frame, then it
passes "oldset" to the callees, down to setup_rt_frame().
This is ugly, setup_rt_frame() can do this itself and nobody
else needs this sigset_t. Move this code into setup_rt_frame.
2. do_signal() also clears TS_RESTORE_SIGMASK if handle_signal()
succeeds.
We can move this to setup_rt_frame() as well, this avoids the
unnecessary checks and makes the logic more clear.
3. use set_current_blocked() instead of sigprocmask(SIG_SETMASK),
sigprocmask() should be avoided.
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Link: http://lkml.kernel.org/r/20110710182203.GA27979@redhat.com
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Instead of hw_nmi_watchdog_set_attr() weak function
and appropriate x86_pmu::hw_watchdog_set_attr() call
we introduce even alias mechanism which allow us
to drop this routines completely and isolate quirks
of Netburst architecture inside P4 PMU code only.
The main idea remains the same though -- to allow
nmi-watchdog and perf top run simultaneously.
Note the aliasing mechanism applies to generic
PERF_COUNT_HW_CPU_CYCLES event only because arbitrary
event (say passed as RAW initially) might have some
additional bits set inside ESCR register changing
the behaviour of event and we can't guarantee anymore
that alias event will give the same result.
P.S. Thanks a huge to Don and Steven for for testing
and early review.
Acked-by: Don Zickus <dzickus@redhat.com>
Tested-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
CC: Ingo Molnar <mingo@elte.hu>
CC: Peter Zijlstra <a.p.zijlstra@chello.nl>
CC: Stephane Eranian <eranian@google.com>
CC: Lin Ming <ming.m.lin@intel.com>
CC: Arnaldo Carvalho de Melo <acme@redhat.com>
CC: Frederic Weisbecker <fweisbec@gmail.com>
Link: http://lkml.kernel.org/r/20110708201712.GS23657@sun
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Since 2.6.36 (23016bf0d2), Linux prints the existence of "epb" in /proc/cpuinfo,
Since 2.6.38 (d5532ee7b4), the x86_energy_perf_policy(8) utility has
been available in-tree to update MSR_IA32_ENERGY_PERF_BIAS.
However, the typical BIOS fails to initialize the MSR, presumably
because this is handled by high-volume shrink-wrap operating systems...
Linux distros, on the other hand, do not yet invoke x86_energy_perf_policy(8).
As a result, WSM-EP, SNB, and later hardware from Intel will run in its
default hardware power-on state (performance), which assumes that users
care for performance at all costs and not for energy efficiency.
While that is fine for performance benchmarks, the hardware's intended default
operating point is "normal" mode...
Initialize the MSR to the "normal" by default during kernel boot.
x86_energy_perf_policy(8) is available to change the default after boot,
should the user have a different preference.
Signed-off-by: Len Brown <len.brown@intel.com>
Link: http://lkml.kernel.org/r/alpine.LFD.2.02.1107140051020.18606@x980
Acked-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Cc: <stable@kernel.org>
Other than sanity check and debug message, the x86 specific version of
memblock reserve/free functions are simple wrappers around the generic
versions - memblock_reserve/free().
This patch adds debug messages with caller identification to the
generic versions and replaces x86 specific ones and kills them.
arch/x86/include/asm/memblock.h and arch/x86/mm/memblock.c are empty
after this change and removed.
Signed-off-by: Tejun Heo <tj@kernel.org>
Link: http://lkml.kernel.org/r/1310462166-31469-14-git-send-email-tj@kernel.org
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
memblock_find_dma_reserve() wants to find out how much memory is
reserved under MAX_DMA_PFN. memblock_x86_memory_[free_]in_range() are
used to find out the amounts of all available and free memory in the
area, which are then subtracted to find out the amount of reservation.
memblock_x86_memblock_[free_]in_range() are implemented using
__memblock_x86_memory_in_range() which builds ranges from memblock and
then count them, which is rather unnecessarily complex.
This patch open codes the counting logic directly in
memblock_find_dma_reserve() using memblock iterators and removes now
unused __memblock_x86_memory_in_range() and find_range_array().
Signed-off-by: Tejun Heo <tj@kernel.org>
Link: http://lkml.kernel.org/r/1310462166-31469-11-git-send-email-tj@kernel.org
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
This patch adds a function pointer in one of the many paravirt_ops
structs, to allow guests to register a steal time function. Besides
a steal time function, we also declare two jump_labels. They will be
used to allow the steal time code to be easily bypassed when not
in use.
Signed-off-by: Glauber Costa <glommer@redhat.com>
Acked-by: Rik van Riel <riel@redhat.com>
Tested-by: Eric B Munson <emunson@mgebm.net>
CC: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
CC: Peter Zijlstra <peterz@infradead.org>
CC: Anthony Liguori <aliguori@us.ibm.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
When "apic=debug" is used as a boot parameter, Linux prints the IOAPIC routing
entries in "dmesg". Below is output from IOAPIC whose apic_id is 8:
# dmesg | grep "routing entry"
IOAPIC[8]: Set routing entry (8-1 -> 0x31 -> IRQ 1 Mode:0 Active:0 Dest:0)
IOAPIC[8]: Set routing entry (8-2 -> 0x30 -> IRQ 0 Mode:0 Active:0 Dest:0)
IOAPIC[8]: Set routing entry (8-3 -> 0x33 -> IRQ 3 Mode:0 Active:0 Dest:0)
...
Similarly, when IR (interrupt remapping) is enabled, and the IRTE
(interrupt remapping table entry) is set up we should display it.
After the fix:
# dmesg | grep IRTE
IOAPIC[8]: Set IRTE entry (P:1 FPD:0 Dst_Mode:0 Redir_hint:1 Trig_Mode:0 Dlvry_Mode:0 Avail:0 Vector:31 Dest:00000000 SID:00F1 SQ:0 SVT:1)
IOAPIC[8]: Set IRTE entry (P:1 FPD:0 Dst_Mode:0 Redir_hint:1 Trig_Mode:0 Dlvry_Mode:0 Avail:0 Vector:30 Dest:00000000 SID:00F1 SQ:0 SVT:1)
IOAPIC[8]: Set IRTE entry (P:1 FPD:0 Dst_Mode:0 Redir_hint:1 Trig_Mode:0 Dlvry_Mode:0 Avail:0 Vector:33 Dest:00000000 SID:00F1 SQ:0 SVT:1)
...
The IRTE is defined in Sec 9.5 of the Intel VT-d Specification.
Signed-off-by: Naga Chumbalkar <nagananda.chumbalkar@hp.com>
Link: http://lkml.kernel.org/r/20110712211704.2939.71291.sendpatchset@nchumbalkar.americas.cpqcorp.net
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
The code in setup_ioapic_irq() determines the Destination Field,
so why not also include it in the debug printk output that gets
displayed when the boot parameter "apic=debug" is used.
Before the change, "dmesg" will show:
IOAPIC[0]: Set routing entry (8-1 -> 0x31 -> IRQ 1 Mode:0 Active:0)
IOAPIC[0]: Set routing entry (8-2 -> 0x30 -> IRQ 0 Mode:0 Active:0)
IOAPIC[0]: Set routing entry (8-3 -> 0x33 -> IRQ 3 Mode:0 Active:0) ...
After the change, you will see:
IOAPIC[0]: Set routing entry (8-1 -> 0x31 -> IRQ 1 Mode:0 Active:0 Dest:0)
IOAPIC[0]: Set routing entry (8-2 -> 0x30 -> IRQ 0 Mode:0 Active:0 Dest:0)
IOAPIC[0]: Set routing entry (8-3 -> 0x33 -> IRQ 3 Mode:0 Active:0 Dest:0) ...
Signed-off-by: Naga Chumbalkar <nagananda.chumbalkar@hp.com>
Link: http://lkml.kernel.org/r/20110708184603.2734.91071.sendpatchset@nchumbalkar.americas.cpqcorp.net
Signed-off-by: Ingo Molnar <mingo@elte.hu>
When IOAPIC data is displayed in "dmesg" with the help of the
boot parameter "apic=debug" certain values are not formatted
correctly wrt their size.
In the "dmesg" snippet below, note that the output for "max
redirection entries", and "IO APIC version" which are each
defined to be just 8-bits long are displayed as 2 bytes in
length. Similarly, "Dst" under the "IRQ redirection table"
should only be 8-bits long.
IO APIC #0......
...
...
.... register #01: 00170020
....... : max redirection entries: 0017
....... : PRQ implemented: 0
....... : IO APIC version: 0020
...
...
.... IRQ redirection table:
NR Dst Mask Trig IRR Pol Stat Dmod Deli Vect:
00 000 1 0 0 0 0 0 0 00
01 000 0 0 0 0 0 0 0 31
02 000 0 0 0 0 0 0 0 30
03 000 1 0 0 0 0 0 0 33
...
...
Do some formatting clean up, so you will see output like below:
IO APIC #0......
...
...
.... register #01: 00170020
....... : max redirection entries: 17
....... : PRQ implemented: 0
....... : IO APIC version: 20
...
...
.... IRQ redirection table:
NR Dst Mask Trig IRR Pol Stat Dmod Deli Vect:
00 00 1 0 0 0 0 0 0 00
01 00 0 0 0 0 0 0 0 31
02 00 0 0 0 0 0 0 0 30
03 00 1 0 0 0 0 0 0 33
...
...
Signed-off-by: Naga Chumbalkar <nagananda.chumbalkar@hp.com>
Link: http://lkml.kernel.org/r/20110708184557.2734.61830.sendpatchset@nchumbalkar.americas.cpqcorp.net
Signed-off-by: Ingo Molnar <mingo@elte.hu>
nr_cpus allows one to specify number of possible cpus in the system.
Current assumption seems to be that first cpu to show up is boot cpu
and this assumption will be broken in kdump scenario where we can be
booting on a non boot cpu with nr_cpus=1.
It might happen that first cpu we parse is not the cpu we boot on and
later we ignore boot cpu. Though code later seems to recognize this
anomaly and forcibly sets boot cpu in physical cpu map with following
warning.
if (!physid_isset(hard_smp_processor_id(), phys_cpu_present_map)) {
printk(KERN_WARNING
"weird, boot CPU (#%d) not listed by the BIOS.\n",
hard_smp_processor_id());
physid_set(hard_smp_processor_id(), phys_cpu_present_map);
}
This patch waits for boot cpu to show up and starts ignoring the cpus
once we have hit (nr_cpus - 1) number of cpus. So effectively we are
reserving one slot out of nr_cpus for boot cpu explicitly.
Signed-off-by: Vivek Goyal <vgoyal@redhat.com>
Acked-by: Yinghai Lu <yinghai@kernel.org>
Link: http://lkml.kernel.org/r/20110708171926.GF2930@redhat.com
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Some BIOSes will reset the Intel MISC_ENABLE MSR (specifically the
XD_DISABLE bit) when resuming from S3, which can interact poorly with
ebba638ae7. In 32bit PAE mode, this can
lead to a fault when EFER is restored by the kernel wakeup routines,
due to it setting the NX bit for a CPU that (thanks to the BIOS reset)
now incorrectly thinks it lacks the NX feature. (64bit is not affected
because it uses a common CPU bring-up that specifically handles the
XD_DISABLE bit.)
The need for MISC_ENABLE being restored so early is specific to the S3
resume path. Normally, MISC_ENABLE is saved in save_processor_state(),
but this happens after the resume header is created, so just reproduce
the logic here. (acpi_suspend_lowlevel() creates the header, calls
do_suspend_lowlevel, which calls save_processor_state(), so the saved
processor context isn't available during resume header creation.)
[ hpa: Consider for stable if OK in mainline ]
Signed-off-by: Kees Cook <kees.cook@canonical.com>
Link: http://lkml.kernel.org/r/20110707011034.GA8523@outflux.net
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Cc: Rafael J. Wysocki <rjw@sisk.pl>
Cc: <stable@kernel.org> 2.6.38+
Since git commit
660e34cebf x86: reorder reboot method
preferences,
my Acer Aspire One hangs on reboot. It appears that its ACPI method
for rebooting is broken. The attached patch adds a quirk so that the
machine will reboot via the BIOS.
[ hpa: verified that the ACPI control on this machine is just plain broken. ]
Signed-off-by: Peter Chubb <peter.chubb@nicta.com.au>
Link: http://lkml.kernel.org/r/w439iki5vl.wl%25peter@chubb.wattle.id.au
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
rbp is used in SAVE_ARGS_IRQ to save the old stack pointer
in order to restore it later in ret_from_intr.
It is convenient because we save its value in the irq regs
and it's easily restored using the leave instruction.
However this is a kind of abuse of the frame pointer which
role is to help unwinding the kernel by chaining frames
together, each node following the return address to the
previous frame.
But although we are breaking the frame by changing the stack
pointer, there is no preceding return address before the new
frame. Hence using the frame pointer to link the two stacks
breaks the stack unwinders that find a random value instead of
a return address here.
There is no workaround that can work in every case. We are using
the fixup_bp_irq_link() function to dereference that abused frame
pointer in the case of non nesting interrupt (which means stack
changed).
But that doesn't fix the case of interrupts that don't change the
stack (but we still have the unconditional frame link), which is
the case of hardirq interrupting softirq. We have no way to detect
this transition so the frame irq link is considered as a real frame
pointer and the return address is dereferenced but it is still a
spurious one.
There are two possible results of this: either the spurious return
address, a random stack value, luckily belongs to the kernel text
and then the unwinding can continue and we just have a weird entry
in the stack trace. Or it doesn't belong to the kernel text and
unwinding stops there.
This is the reason why stacktraces (including perf callchains) on
irqs that interrupted softirqs don't work very well.
To solve this, we don't save the old stack pointer on rbp anymore
but we save it to a scratch register that we push on the new
stack and that we pop back later on irq return.
This preserves the whole frame chain without spurious return addresses
in the middle and drops the need for the horrid fixup_bp_irq_link()
workaround.
And finally irqs that interrupt softirq are sanely unwinded.
Before:
99.81% perf [kernel.kallsyms] [k] perf_pending_event
|
--- perf_pending_event
irq_work_run
smp_irq_work_interrupt
irq_work_interrupt
|
|--41.60%-- __read
| |
| |--99.90%-- create_worker
| | bench_sched_messaging
| | cmd_bench
| | run_builtin
| | main
| | __libc_start_main
| --0.10%-- [...]
After:
1.64% swapper [kernel.kallsyms] [k] perf_pending_event
|
--- perf_pending_event
irq_work_run
smp_irq_work_interrupt
irq_work_interrupt
|
|--95.00%-- arch_irq_work_raise
| irq_work_queue
| __perf_event_overflow
| perf_swevent_overflow
| perf_swevent_event
| perf_tp_event
| perf_trace_softirq
| __do_softirq
| call_softirq
| do_softirq
| irq_exit
| |
| |--73.68%-- smp_apic_timer_interrupt
| | apic_timer_interrupt
| | |
| | |--96.43%-- amd_e400_idle
| | | cpu_idle
| | | start_secondary
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jan Beulich <JBeulich@novell.com>
The save_regs function that saves the regs on low level
irq entry is complicated because of the fact it changes
its stack in the middle and also because it manipulates
data allocated in the caller frame and accesses there
are directly calculated from callee rsp value with the
return address in the middle of the way.
This complicates the static stack offsets calculation and
require more dynamic ones. It also needs a save/restore
of the function's return address.
To simplify and optimize this, turn save_regs() into a
macro.
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jan Beulich <JBeulich@novell.com>
When regs are passed to dump_stack(), we fetch the frame
pointer from the regs but the stack pointer is taken from
the current frame.
Thus the frame and stack pointers may not come from the same
context. For example this can result in the unwinder to
think the context is in irq, due to the current value of
the stack, but the frame pointer coming from the regs points
to a frame from another place. It then tries to fix up
the irq link but ends up dereferencing a random frame
pointer that doesn't belong to the irq stack:
[ 9131.706906] ------------[ cut here ]------------
[ 9131.707003] WARNING: at arch/x86/kernel/dumpstack_64.c:129 dump_trace+0x2aa/0x330()
[ 9131.707003] Hardware name: AMD690VM-FMH
[ 9131.707003] Perf: bad frame pointer = 0000000000000005 in callchain
[ 9131.707003] Modules linked in:
[ 9131.707003] Pid: 1050, comm: perf Not tainted 3.0.0-rc3+ #181
[ 9131.707003] Call Trace:
[ 9131.707003] <IRQ> [<ffffffff8104bd4a>] warn_slowpath_common+0x7a/0xb0
[ 9131.707003] [<ffffffff8104be21>] warn_slowpath_fmt+0x41/0x50
[ 9131.707003] [<ffffffff8178b873>] ? bad_to_user+0x6d/0x10be
[ 9131.707003] [<ffffffff8100c2da>] dump_trace+0x2aa/0x330
[ 9131.707003] [<ffffffff810107d3>] ? native_sched_clock+0x13/0x50
[ 9131.707003] [<ffffffff8101b164>] perf_callchain_kernel+0x54/0x70
[ 9131.707003] [<ffffffff810d391f>] perf_prepare_sample+0x19f/0x2a0
[ 9131.707003] [<ffffffff810d546c>] __perf_event_overflow+0x16c/0x290
[ 9131.707003] [<ffffffff810d5430>] ? __perf_event_overflow+0x130/0x290
[ 9131.707003] [<ffffffff810107d3>] ? native_sched_clock+0x13/0x50
[ 9131.707003] [<ffffffff8100fbb9>] ? sched_clock+0x9/0x10
[ 9131.707003] [<ffffffff810752e5>] ? T.375+0x15/0x90
[ 9131.707003] [<ffffffff81084da4>] ? trace_hardirqs_on_caller+0x64/0x180
[ 9131.707003] [<ffffffff810817bd>] ? trace_hardirqs_off+0xd/0x10
[ 9131.707003] [<ffffffff810d5764>] perf_event_overflow+0x14/0x20
[ 9131.707003] [<ffffffff810d588c>] perf_swevent_hrtimer+0x11c/0x130
[ 9131.707003] [<ffffffff817821a1>] ? error_exit+0x51/0xb0
[ 9131.707003] [<ffffffff81072e93>] __run_hrtimer+0x83/0x1e0
[ 9131.707003] [<ffffffff810d5770>] ? perf_event_overflow+0x20/0x20
[ 9131.707003] [<ffffffff81073256>] hrtimer_interrupt+0x106/0x250
[ 9131.707003] [<ffffffff812a3bfd>] ? trace_hardirqs_off_thunk+0x3a/0x3c
[ 9131.707003] [<ffffffff81024833>] smp_apic_timer_interrupt+0x53/0x90
[ 9131.707003] [<ffffffff81789053>] apic_timer_interrupt+0x13/0x20
[ 9131.707003] <EOI> [<ffffffff817821a1>] ? error_exit+0x51/0xb0
[ 9131.707003] [<ffffffff8178219c>] ? error_exit+0x4c/0xb0
[ 9131.707003] ---[ end trace b2560d4876709347 ]---
Fix this by simply taking the stack pointer from regs->sp
when regs are provided.
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
The perf_event overflow handler does not receive any caller-derived
argument, so many callers need to resort to looking up the perf_event
in their local data structure. This is ugly and doesn't scale if a
single callback services many perf_events.
Fix by adding a context parameter to perf_event_create_kernel_counter()
(and derived hardware breakpoints APIs) and storing it in the perf_event.
The field can be accessed from the callback as event->overflow_handler_context.
All callers are updated.
Signed-off-by: Avi Kivity <avi@redhat.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1309362157-6596-2-git-send-email-avi@redhat.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Add a NODE level to the generic cache events which is used to measure
local vs remote memory accesses. Like all other cache events, an
ACCESS is HIT+MISS, if there is no way to distinguish between reads
and writes do reads only etc..
The below needs filling out for !x86 (which I filled out with
unsupported events).
I'm fairly sure ARM can leave it like that since it doesn't strike me as
an architecture that even has NUMA support. SH might have something since
it does appear to have some NUMA bits.
Sparc64, PowerPC and MIPS certainly want a good look there since they
clearly are NUMA capable.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: David Miller <davem@davemloft.net>
Cc: Anton Blanchard <anton@samba.org>
Cc: David Daney <ddaney@caviumnetworks.com>
Cc: Deng-Cheng Zhu <dengcheng.zhu@gmail.com>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Robert Richter <robert.richter@amd.com>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/r/1303508226.4865.8.camel@laptop
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This patch adds Intel Sandy Bridge offcore_response support by
providing the low-level constraint table for those events.
On Sandy Bridge, there are two offcore_response events. Each uses
its own dedictated extra register. But those registers are NOT shared
between sibling CPUs when HT is on unlike Nehalem/Westmere. They are
always private to each CPU. But they still need to be controlled within
an event group. All events within an event group must use the same
value for the extra MSR. That's not controlled by the second patch in
this series.
Furthermore on Sandy Bridge, the offcore_response events have NO
counter constraints contrary to what the official documentation
indicates, so drop the events from the contraint table.
Signed-off-by: Stephane Eranian <eranian@google.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/20110606145712.GA7304@quad
Signed-off-by: Ingo Molnar <mingo@elte.hu>
The validate_group() function needs to validate events with
extra shared regs. Within an event group, only events with
the same value for the extra reg can co-exist. This was not
checked by validate_group() because it was missing the
shared_regs logic.
This patch changes the allocation of the fake cpuc used for
validation to also point to a fake shared_regs structure such
that group events be properly testing.
It modifies __intel_shared_reg_get_constraints() to use
spin_lock_irqsave() to avoid lockdep issues.
Signed-off-by: Stephane Eranian <eranian@google.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/20110606145708.GA7279@quad
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This patch improves the code managing the extra shared registers
used for offcore_response events on Intel Nehalem/Westmere. The
idea is to use static allocation instead of dynamic allocation.
This simplifies greatly the get and put constraint routines for
those events.
The patch also renames per_core to shared_regs because the same
data structure gets used whether or not HT is on. When HT is
off, those events still need to coordination because they use
a extra MSR that has to be shared within an event group.
Signed-off-by: Stephane Eranian <eranian@google.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/20110606145703.GA7258@quad
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Since only samples call perf_output_sample() its much saner (and more
correct) to put the sample logic in there than in the
perf_output_begin()/perf_output_end() pair.
Saves a useless argument, reduces conditionals and shrinks
struct perf_output_handle, win!
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/n/tip-2crpvsx3cqu67q3zqjbnlpsc@git.kernel.org
Signed-off-by: Ingo Molnar <mingo@elte.hu>
The nmi parameter indicated if we could do wakeups from the current
context, if not, we would set some state and self-IPI and let the
resulting interrupt do the wakeup.
For the various event classes:
- hardware: nmi=0; PMI is in fact an NMI or we run irq_work_run from
the PMI-tail (ARM etc.)
- tracepoint: nmi=0; since tracepoint could be from NMI context.
- software: nmi=[0,1]; some, like the schedule thing cannot
perform wakeups, and hence need 0.
As one can see, there is very little nmi=1 usage, and the down-side of
not using it is that on some platforms some software events can have a
jiffy delay in wakeup (when arch_irq_work_raise isn't implemented).
The up-side however is that we can remove the nmi parameter and save a
bunch of conditionals in fast paths.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Michael Cree <mcree@orcon.net.nz>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Deng-Cheng Zhu <dengcheng.zhu@gmail.com>
Cc: Anton Blanchard <anton@samba.org>
Cc: Eric B Munson <emunson@mgebm.net>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: David S. Miller <davem@davemloft.net>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jason Wessel <jason.wessel@windriver.com>
Cc: Don Zickus <dzickus@redhat.com>
Link: http://lkml.kernel.org/n/tip-agjev8eu666tvknpb3iaj0fg@git.kernel.org
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Due to restriction and specifics of Netburst PMU we need a separated
event for NMI watchdog. In particular every Netburst event
consumes not just a counter and a config register, but also an
additional ESCR register.
Since ESCR registers are grouped upon counters (i.e. if ESCR is occupied
for some event there is no room for another event to enter until its
released) we need to pick up the "least" used ESCR (or the most available
one) for nmi-watchdog purposes -- so MSR_P4_CRU_ESCR2/3 was chosen.
With this patch nmi-watchdog and perf top should be able to run simultaneously.
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
CC: Lin Ming <ming.m.lin@intel.com>
CC: Arnaldo Carvalho de Melo <acme@redhat.com>
CC: Frederic Weisbecker <fweisbec@gmail.com>
Tested-and-reviewed-by: Don Zickus <dzickus@redhat.com>
Tested-and-reviewed-by: Stephane Eranian <eranian@google.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/20110623124918.GC13050@sun
Signed-off-by: Ingo Molnar <mingo@elte.hu>
