To help users determine domains, display the domain indices used by the
kernel in sysfs.
$ cat /sys/bus/event_source/devices/hv_24x7/interface/domains
1: Physical Chip
2: Physical Core
3: VCPU Home Core
4: VCPU Home Chip
5: VCPU Home Node
6: VCPU Remote Node
Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
For 24x7 counters, perf displays the raw value of the 24x7 counter, which
is a monotonically increasing value.
perf stat -C 0 -e \
'hv_24x7/HPM_0THRD_NON_IDLE_CCYC__PHYS_CORE,core=1/' \
sleep 1
Performance counter stats for 'CPU(s) 0':
9,105,403,170 hv_24x7/HPM_0THRD_NON_IDLE_CCYC__PHYS_CORE,core=1/
0.000425751 seconds time elapsed
In the typical usage of 'perf stat' this counter value is not as useful
as the _change_ in the counter value over the duration of the application.
Have h_24x7_event_init() set the event's prev_count to the raw value of
the 24x7 counter at the time of initialization. When the application
terminates, hv_24x7_event_read() will compute the change in value and
report to the perf tool. Similarly, for the transaction interface, clear
the event count to 0 at the beginning of the transaction.
perf stat -C 0 -e \
'hv_24x7/HPM_0THRD_NON_IDLE_CCYC__PHYS_CORE,core=1/' \
sleep 1
Performance counter stats for 'CPU(s) 0':
245,758 hv_24x7/HPM_0THRD_NON_IDLE_CCYC__PHYS_CORE,core=1/
1.006366383 seconds time elapsed
Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
24x7 counters can belong to different domains (core, chip, virtual CPU
etc). For events in the 'chip' domain, sysfs entry currently looks like:
$ cd /sys/bus/event_source/devices/hv_24x7/events
$ cat PM_XLINK_CYCLES__PHYS_CHIP
domain=0x1,offset=0x230,core=?,lpar=0x0
where the required parameter, 'core=?' is specified with perf as:
perf stat -C 0 -e hv_24x7/PM_XLINK_CYCLES__PHYS_CHIP,core=1/ \
/bin/true
This is inconsistent in that 'core' is a required parameter for a chip
event. Instead, have the the sysfs entry display 'chip=?' for chip
events:
$ cd /sys/bus/event_source/devices/hv_24x7/events
$ cat PM_XLINK_CYCLES__PHYS_CHIP
domain=0x1,offset=0x230,chip=?,lpar=0x0
We also need to add a 'chip' entry in the sysfs format directory:
$ ls /sys/bus/event_source/devices/hv_24x7/format
chip core domain lpar offset vcpu
^^^^
(new)
so the perf tool can automatically check usage and format the chip
parameter correctly:
$ perf stat -C 0 -v -e hv_24x7/PM_XLINK_CYCLES__PHYS_CHIP/ \
/bin/true
Required parameter 'chip' not specified
invalid or unsupported event: 'hv_24x7/PM_XLINK_CYCLES__PHYS_CHIP/'
$ perf stat -C 0 -v -e hv_24x7/PM_XLINK_CYCLES__PHYS_CHIP,chip=1/ \
/bin/true
hv_24x7/PM_XLINK_CYCLES__PHYS_CHIP,chip=1/: 0 6628908 6628908
Performance counter stats for 'CPU(s) 0':
0 hv_24x7/PM_XLINK_CYCLES__PHYS_CHIP,chip=1/
0.006606970 seconds time elapsed
Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
The 24x7 counters in Powerpc allow monitoring a large number of counters
simultaneously. They also allow reading several counters in a single
HCALL so we can get a more consistent snapshot of the system.
Use the PMU's transaction interface to monitor and read several event
counters at once. The idea is that users can group several 24x7 events
into a single group of events. We use the following logic to submit
the group of events to the PMU and read the values:
pmu->start_txn() // Initialize before first event
for each event in group
pmu->read(event); // Queue each event to be read
pmu->commit_txn() // Read/update all queuedcounters
The ->commit_txn() also updates the event counts in the respective
perf_event objects. The perf subsystem can then directly get the
event counts from the perf_event and can avoid submitting a new
->read() request to the PMU.
Thanks to input from Peter Zijlstra.
Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Michael Ellerman <mpe@ellerman.id.au>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Link: http://lkml.kernel.org/r/1441336073-22750-10-git-send-email-sukadev@linux.vnet.ibm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Simplify code that extracts a 24x7 counter from the HCALL's result buffer.
Suggested-by: Joe Perches <joe@perches.com>
Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Fix parameter alignment to be consistent with coding style.
Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
- Numerous minor fixes, cleanups etc.
- More EEH work from Gavin to remove its dependency on device_nodes.
- Memory hotplug implemented entirely in the kernel from Nathan Fontenot.
- Removal of redundant CONFIG_PPC_OF by Kevin Hao.
- Rewrite of VPHN parsing logic & tests from Greg Kurz.
- A fix from Nish Aravamudan to reduce memory usage by clamping
nodes_possible_map.
- Support for pstore on powernv from Hari Bathini.
- Removal of old powerpc specific byte swap routines by David Gibson.
- Fix from Vasant Hegde to prevent the flash driver telling you it was flashing
your firmware when it wasn't.
- Patch from Ben Herrenschmidt to add an OPAL heartbeat driver.
- Fix for an oops causing get/put_cpu_var() imbalance in perf by Jan Stancek.
- Some fixes for migration from Tyrel Datwyler.
- A new syscall to switch the cpu endian by Michael Ellerman.
- Large series from Wei Yang to implement SRIOV, reviewed and acked by Bjorn.
- A fix for the OPAL sensor driver from Cédric Le Goater.
- Fixes to get STRICT_MM_TYPECHECKS building again by Michael Ellerman.
- Large series from Daniel Axtens to make our PCI hooks per PHB rather than per
machine.
- Small patch from Sam Bobroff to explicitly abort non-suspended transactions
on syscalls, plus a test to exercise it.
- Numerous reworks and fixes for the 24x7 PMU from Sukadev Bhattiprolu.
- Small patch to enable the hard lockup detector from Anton Blanchard.
- Fix from Dave Olson for missing L2 cache information on some CPUs.
- Some fixes from Michael Ellerman to get Cell machines booting again.
- Freescale updates from Scott: Highlights include BMan device tree nodes, an
MSI erratum workaround, a couple minor performance improvements, config
updates, and misc fixes/cleanup.
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Merge tag 'powerpc-4.1-1' of git://git.kernel.org/pub/scm/linux/kernel/git/mpe/linux
Pull powerpc updates from Michael Ellerman:
- Numerous minor fixes, cleanups etc.
- More EEH work from Gavin to remove its dependency on device_nodes.
- Memory hotplug implemented entirely in the kernel from Nathan
Fontenot.
- Removal of redundant CONFIG_PPC_OF by Kevin Hao.
- Rewrite of VPHN parsing logic & tests from Greg Kurz.
- A fix from Nish Aravamudan to reduce memory usage by clamping
nodes_possible_map.
- Support for pstore on powernv from Hari Bathini.
- Removal of old powerpc specific byte swap routines by David Gibson.
- Fix from Vasant Hegde to prevent the flash driver telling you it was
flashing your firmware when it wasn't.
- Patch from Ben Herrenschmidt to add an OPAL heartbeat driver.
- Fix for an oops causing get/put_cpu_var() imbalance in perf by Jan
Stancek.
- Some fixes for migration from Tyrel Datwyler.
- A new syscall to switch the cpu endian by Michael Ellerman.
- Large series from Wei Yang to implement SRIOV, reviewed and acked by
Bjorn.
- A fix for the OPAL sensor driver from Cédric Le Goater.
- Fixes to get STRICT_MM_TYPECHECKS building again by Michael Ellerman.
- Large series from Daniel Axtens to make our PCI hooks per PHB rather
than per machine.
- Small patch from Sam Bobroff to explicitly abort non-suspended
transactions on syscalls, plus a test to exercise it.
- Numerous reworks and fixes for the 24x7 PMU from Sukadev Bhattiprolu.
- Small patch to enable the hard lockup detector from Anton Blanchard.
- Fix from Dave Olson for missing L2 cache information on some CPUs.
- Some fixes from Michael Ellerman to get Cell machines booting again.
- Freescale updates from Scott: Highlights include BMan device tree
nodes, an MSI erratum workaround, a couple minor performance
improvements, config updates, and misc fixes/cleanup.
* tag 'powerpc-4.1-1' of git://git.kernel.org/pub/scm/linux/kernel/git/mpe/linux: (196 commits)
powerpc/powermac: Fix build error seen with powermac smp builds
powerpc/pseries: Fix compile of memory hotplug without CONFIG_MEMORY_HOTREMOVE
powerpc: Remove PPC32 code from pseries specific find_and_init_phbs()
powerpc/cell: Fix iommu breakage caused by controller_ops change
powerpc/eeh: Fix crash in eeh_add_device_early() on Cell
powerpc/perf: Cap 64bit userspace backtraces to PERF_MAX_STACK_DEPTH
powerpc/perf/hv-24x7: Fail 24x7 initcall if create_events_from_catalog() fails
powerpc/pseries: Correct memory hotplug locking
powerpc: Fix missing L2 cache size in /sys/devices/system/cpu
powerpc: Add ppc64 hard lockup detector support
oprofile: Disable oprofile NMI timer on ppc64
powerpc/perf/hv-24x7: Add missing put_cpu_var()
powerpc/perf/hv-24x7: Break up single_24x7_request
powerpc/perf/hv-24x7: Define update_event_count()
powerpc/perf/hv-24x7: Whitespace cleanup
powerpc/perf/hv-24x7: Define add_event_to_24x7_request()
powerpc/perf/hv-24x7: Rename hv_24x7_event_update
powerpc/perf/hv-24x7: Move debug prints to separate function
powerpc/perf/hv-24x7: Drop event_24x7_request()
powerpc/perf/hv-24x7: Use pr_devel() to log message
...
Conflicts:
tools/testing/selftests/powerpc/Makefile
tools/testing/selftests/powerpc/tm/Makefile
Pull trivial tree from Jiri Kosina:
"Usual trivial tree updates. Nothing outstanding -- mostly printk()
and comment fixes and unused identifier removals"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial:
goldfish: goldfish_tty_probe() is not using 'i' any more
powerpc: Fix comment in smu.h
qla2xxx: Fix printks in ql_log message
lib: correct link to the original source for div64_u64
si2168, tda10071, m88ds3103: Fix firmware wording
usb: storage: Fix printk in isd200_log_config()
qla2xxx: Fix printk in qla25xx_setup_mode
init/main: fix reset_device comment
ipwireless: missing assignment
goldfish: remove unreachable line of code
coredump: Fix do_coredump() comment
stacktrace.h: remove duplicate declaration task_struct
smpboot.h: Remove unused function prototype
treewide: Fix typo in printk messages
treewide: Fix typo in printk messages
mod_devicetable: fix comment for match_flags
As Michael pointed out, create_events_from_catalog() fails when we
either have:
- a kernel bug
- some sort of hypervisor misconfiguration
- ENOMEM
In all the above cases, we can also fail 24x7 initcall.
For hypervisor errors, EIO is used so there is something reported
in dmesg.
Signed-off-by: Li Zhong <zhong@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Add missing put_cpu_var() for 24x7 requests. This went missing in
commit f34b6c7 (3.18-rc3).
Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Break up the function single_24x7_request() into smaller functions.
This would later enable us to "prepare" a multi-event request
buffer and then submit a single hcall for several events.
Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Move the code to update an event count into a new function,
update_event_count().
Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Move code that maps a perf_event to a 24x7 request buffer into a
separate function, add_event_to_24x7_request().
Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
For consistency with the pmu operation ->read() and with other
pmus, rename hv_24x7_event_update() to hv_24x7_event_read().
Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
To simplify/cleanup code, move the rather long printk() to a separate
function.
Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
The function event_24x7_request() is essentially a wrapper to the
function single_24x7_request() and can be dropped to simplify code.
Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Use pr_devel_ratelimited() to log error message when the 24x7 HCALL
fails. Since users specify events by their sysfs name, the HCALL should
succeed. Any errors reported by the HCALL would be of interest to the
developer, rather than the user/administrator.
Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Remove the 'success_expected' parameter and log the message unconditionally.
Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
The parameters to the 24x7 HCALL have variable number of elements in them.
Set the minimum number of such elements to 1 rather than 0 and eliminate
the temporary structures.
This would enable us to submit multiple counter requests and process
multiple results from a single HCALL (in a follow on patch).
Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Retrieves and parses the 24x7 catalog on POWER systems that supply it
(right now, only POWER 8). Events are exposed via sysfs in the standard
fashion, and are all parameterized.
$ cd /sys/bus/event_source/devices/hv_24x7/events
$ cat HPM_CS_FROM_L4_LDATA__PHYS_CORE
domain=0x2,offset=0xd58,core=?,lpar=0x0
$ cat HPM_TLBIE__VCPU_HOME_CHIP
domain=0x4,offset=0x358,vcpu=?,lpar=?
where user is required to specify values for the fields with '?' (like
core, vcpu, lpar above), when specifying the event with the perf tool.
Catalog is (at the moment) only parsed on boot. It needs re-parsing
when a some hypervisor events occur. At that point we'll also need to
prevent old events from continuing to function (counter that is passed
in via spare space in the config values?).
Signed-off-by: Cody P Schafer <cody@linux.vnet.ibm.com>
Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Use kmem_cache_free() to free a buffer allocated with kmem_cache_alloc().
Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
The 24x7 counters are continuously running and not updated on an
interrupt. So we record the event counts when stopping the event or
deleting it.
But to "read" a single counter in 24x7, we allocate a page and pass it
into the hypervisor (The HV returns the page full of counters from which
we extract the specific counter for this event).
We allocate a page using GFP_USER and when deleting the event, we end up
with the following warning because we are blocking in interrupt context.
[ 698.641709] BUG: scheduling while atomic: swapper/0/0/0x10010000
We could use GFP_ATOMIC but that could result in failures. Pre-allocate
a buffer so we don't have to allocate in interrupt context. Further as
Michael Ellerman suggested, use Per-CPU buffer so we only need to
allocate once per CPU.
Cc: stable@vger.kernel.org
Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Andy reported that the current state of event_idx is rather confused.
So remove all but the x86_pmu implementation and change the default to
return 0 (the safe option).
Reported-by: Andy Lutomirski <luto@amacapital.net>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Christoph Lameter <cl@linux.com>
Cc: Cody P Schafer <cody@linux.vnet.ibm.com>
Cc: Cody P Schafer <dev@codyps.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Cc: Himangi Saraogi <himangi774@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Paul Gortmaker <paul.gortmaker@windriver.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: sukadev@linux.vnet.ibm.com <sukadev@linux.vnet.ibm.com>
Cc: Thomas Huth <thuth@linux.vnet.ibm.com>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Cc: linux390@de.ibm.com
Cc: linuxppc-dev@lists.ozlabs.org
Cc: linux-s390@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
catalog_read() implements the read interface for the sysfs file
/sys/bus/event_source/devices/hv_24x7/interface/catalog
It essentially takes a buffer, an offset and count as parameters
to the read() call. It makes a hypervisor call to read a specific
page from the catalog and copy the required bytes into the given
buffer. Each call to catalog_read() returns at most one 4K page.
Given these requirements, we should be able to simplify the
catalog_read().
Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Ian pointed out the use of __aligned(4096) caused rather large stack
consumption in single_24x7_request(), so use the kmem_cache
hv_page_cache (which we've already got set up for other allocations)
insead of allocating locally.
CC: Haren Myneni <hbabu@us.ibm.com>
Reported-by: Ian Munsie <imunsie@au1.ibm.com>
Signed-off-by: Cody P Schafer <dev@codyps.com>
Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Free memory allocated using kmem_cache_zalloc using kmem_cache_free
rather than kfree.
The Coccinelle semantic patch that makes this change is as follows:
// <smpl>
@@
expression x,E,c;
@@
x = \(kmem_cache_alloc\|kmem_cache_zalloc\|kmem_cache_alloc_node\)(c,...)
... when != x = E
when != &x
?-kfree(x)
+kmem_cache_free(c,x)
// </smpl>
Signed-off-by: Himangi Saraogi <himangi774@gmail.com>
Acked-by: Julia Lawall <julia.lawall@lip6.fr>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Transition to using the new generic PERF_PMU_CAP_NO_INTERRUPT method for
failing a sampling event when no PMU interrupt is available.
Signed-off-by: Vince Weaver <vincent.weaver@maine.edu>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/alpine.DEB.2.10.1406191435440.27913@vincent-weaver-1.umelst.maine.edu
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Cody P Schafer <cody@linux.vnet.ibm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Paul Mackerras <paulus@samba.org>
Cc: linux-kernel@vger.kernel.org
Cc: linuxppc-dev@lists.ozlabs.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
The catalog version number was changed from a be32 (with proceeding
32bits of padding) to a be64, update the code to treat it as a be64
Signed-off-by: Cody P Schafer <cody@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
fixup for "powerpc/perf: Add support for the hv 24x7 interface"
Makes the "not enabled" message less awful (and hides it in most cases).
Signed-off-by: Cody P Schafer <cody@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
This provides a basic interface between hv_24x7 and perf. Similar to
the one provided for gpci, it lacks transaction support and does not
list any events.
Example usage via perf tool:
perf stat -e 'hv_24x7/domain=2,offset=8,starting_index=0,lpar=0xffffffff/' -r 0 -C 0 -x ' ' sleep 0.1
Signed-off-by: Cody P Schafer <cody@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
