coresight: Fix issue where a source device's helpers aren't disabled

The linked commit reverts the change that accidentally used some sysfs
enable/disable functions from Perf which broke the refcounting, but it
also removes the fact that the sysfs disable function disabled the
helpers.

Add a new wrapper function that does both which is used by both Perf and
sysfs, and label the sysfs disable function appropriately. The naming of
all of the functions will be tidied up later to avoid this happening
again.

Fixes: 287e82cf69aa ("coresight: Fix crash when Perf and sysfs modes are used concurrently")
Signed-off-by: James Clark <james.clark@arm.com>
Link: https://lore.kernel.org/r/20240129154050.569566-2-james.clark@arm.com
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>

coresight: etm: Make cycle count threshold user configurable

When cycle counting is enabled, we use a default threshold value i.e 0x100
for the instruction trace cycle counting.

This patch makes the cycle threshold user configurable via perf event
attributes( 'cc_threshold' => event->attr.config3[11:0] ), falling back
to the current default if unspecified.

Cc: Suzuki K Poulose <suzuki.poulose@arm.com>
Cc: Mike Leach <mike.leach@linaro.org>
Cc: James Clark <james.clark@arm.com>
Cc: Leo Yan <leo.yan@linaro.org>
Cc: coresight@lists.linaro.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-doc@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Reviewed-by: Mike Leach <mike.leach@linaro.org>
Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Link: https://lore.kernel.org/r/20230921033631.1298723-3-anshuman.khandual@arm.com

coresight: Fix crash when Perf and sysfs modes are used concurrently

Partially revert the change in commit 6148652807ba ("coresight: Enable
and disable helper devices adjacent to the path") which changed the bare
call from source_ops(csdev)->enable() to coresight_enable_source() for
Perf sessions. It was missed that coresight_enable_source() is
specifically for the sysfs interface, rather than being a generic call.
This interferes with the sysfs reference counting to cause the following
crash:

$ perf record -e cs_etm/@tmc_etr0/ -C 0 &
$ echo 1 > /sys/bus/coresight/devices/tmc_etr0/enable_sink
$ echo 1 > /sys/bus/coresight/devices/etm0/enable_source
$ echo 0 > /sys/bus/coresight/devices/etm0/enable_source

Unable to handle kernel NULL pointer dereference at virtual
address 00000000000001d0
Internal error: Oops: 0000000096000004 [#1] PREEMPT SMP
...
Call trace:
etm4_disable+0x54/0x150 [coresight_etm4x]
coresight_disable_source+0x6c/0x98 [coresight]
coresight_disable+0x74/0x1c0 [coresight]
enable_source_store+0x88/0xa0 [coresight]
dev_attr_store+0x20/0x40
sysfs_kf_write+0x4c/0x68
kernfs_fop_write_iter+0x120/0x1b8
vfs_write+0x2dc/0x3b0
ksys_write+0x70/0x108
__arm64_sys_write+0x24/0x38
invoke_syscall+0x50/0x128
el0_svc_common.constprop.0+0x104/0x130
do_el0_svc+0x40/0xb8
el0_svc+0x2c/0xb8
el0t_64_sync_handler+0xc0/0xc8
el0t_64_sync+0x1a4/0x1a8
Code: d53cd042 91002000 b9402a81 b8626800 (f940ead5)
---[ end trace 0000000000000000 ]---

This commit linked below also fixes the issue, but has unlocked updates
to the mode which could potentially race. So until we come up with a
more complete solution that takes all locking and interaction between
both modes into account, just revert back to the old behavior for Perf.

Reported-by: Junhao He <hejunhao3@huawei.com>
Closes: https://lore.kernel.org/linux-arm-kernel/20230921132904.60996-1-hejunhao3@huawei.com/
Fixes: 6148652807ba ("coresight: Enable and disable helper devices adjacent to the path")
Tested-by: Junhao He <hejunhao3@huawei.com>
Signed-off-by: James Clark <james.clark@arm.com>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Link: https://lore.kernel.org/r/20231006131452.646721-1-james.clark@arm.com

coresight: Enable and disable helper devices adjacent to the path

Currently CATU is the only helper device, and its enable and disable
calls are hard coded. To allow more helper devices to be added in a
generic way, remove these hard coded calls and just enable and disable
all helper devices.

This has to apply to helpers adjacent to the path, because they will
never be in the path. CATU was already discovered in this way, so
there is no change there.

One change that is needed is for CATU to call back into ETR to allocate
the buffer. Because the enable call was previously hard coded, it was
done at a point where the buffer was already allocated, but this is no
longer the case.

Reviewed-by: Mike Leach <mike.leach@linaro.org>
Signed-off-by: James Clark <james.clark@arm.com>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Link: https://lore.kernel.org/r/20230425143542.2305069-13-james.clark@arm.com

coresight: perf: Release Coresight path when alloc trace id failed

Error handler for etm_setup_aux can not release coresight path because
cpu mask was cleared when coresight_trace_id_get_cpu_id failed.

Call coresight_release_path function explicitly when alloc trace id filed.

Fixes: 4ff1fdb4125c4 ("coresight: perf: traceid: Add perf ID allocation and notifiers")
Signed-off-by: Ruidong Tian <tianruidong@linux.alibaba.com>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Link: https://lore.kernel.org/r/20230425032416.125542-1-tianruidong@linux.alibaba.com

coresight: etm_pmu: Set the module field

struct pmu::module must be set to the module owning the PMU driver.
Set this for the coresight etm_pmu.

Fixes: 8e264c52e1dab ("coresight: core: Allow the coresight core driver to be built as a module")
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Link: https://lore.kernel.org/r/20230405094922.667834-1-suzuki.poulose@arm.com

coresight: perf: Output trace id only once

With the dynamic traceid allocation scheme in, we output the
AUX_OUTPUT_HWID packet every time event->start() is called.
This could cause too many such records in the perf.data,
while only one per CPU throughout the life time of
the event is required. Make sure we only output it once.

Before this patch:
$ perf report -D | grep OUTPUT_HW_ID
...
AUX_OUTPUT_HW_ID events: 55 (18.3%)

After this patch:

$ perf report -D | grep OUTPUT_HW_ID
...
AUX_OUTPUT_HW_ID events: 5 ( 1.9%)

Cc: Mike Leach <mike.leach@linaro.org>
Cc: James Clark <james.clark@arm.com>
Cc: Leo Yan <leo.yan@linaro.org>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Reviewed-by: James Clark <james.clark@arm.com>
Link: https://lore.kernel.org/r/20230120103434.864318-1-suzuki.poulose@arm.com

coresight: events: PERF_RECORD_AUX_OUTPUT_HW_ID used for Trace ID

Use the perf_report_aux_output_id() call to output the CoreSight trace ID
and associated CPU as a PERF_RECORD_AUX_OUTPUT_HW_ID record in the
perf.data file.

Signed-off-by: Mike Leach <mike.leach@linaro.org>
Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Link: https://lore.kernel.org/r/20230116124928.5440-14-mike.leach@linaro.org

coresight: perf: traceid: Add perf ID allocation and notifiers

Adds in calls to allocate and release Trace ID for the CPUs in use
by the perf session.

Adds in notifier calls to the trace ID allocator that perf
events are starting and stopping.

This ensures that Trace IDs associated with CPUs remain the same
throughout the perf session, and are only released when all perf
sessions are complete.

Signed-off-by: Mike Leach <mike.leach@linaro.org>
Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Link: https://lore.kernel.org/r/20230116124928.5440-4-mike.leach@linaro.org

coresight: Add config flag to enable branch broadcast

When enabled, all taken branch addresses are output, even if the branch
was because of a direct branch instruction. This enables reconstruction
of the program flow without having access to the memory image of the
code being executed.

Use bit 8 for the config option which would be the correct bit for
programming ETMv3. Although branch broadcast can't be enabled on ETMv3
because it's not in the define ETM3X_SUPPORTED_OPTIONS, using the
correct bit might help prevent future collisions or allow it to be
enabled if needed.

Signed-off-by: James Clark <james.clark@arm.com>
Reviewed-by: Mike Leach <mike.leach@linaro.org>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Link: https://lore.kernel.org/r/20220511144601.2257870-2-james.clark@arm.com

coresight: etm-pmu: Ensure the AUX handle is valid

The ETM perf infrastructure closes out a handle during event_stop
or on an error in starting the event. In either case, it is possible
for a "sink" to update/close the handle, under certain circumstances.
(e.g no space in ring buffer.). So, ensure that we handle this
gracefully in the PMU driver by verifying the handle is still valid.

Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Mike Leach <mike.leach@linaro.org>
Cc: Anshuman Khandual <anshuman.khandual@arm.com>
Cc: Leo Yan <leo.yan@linaro.org>
Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Link: https://lore.kernel.org/r/20210914102641.1852544-4-suzuki.poulose@arm.com
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>

coresight: Don't immediately close events that are run on invalid CPU/sink combos

When a traced process runs on a CPU that can't reach the selected sink,
the event will be stopped with PERF_HES_STOPPED. This means that even if
the process migrates to a valid CPU, tracing will not resume.

This can be reproduced (on N1SDP) by using taskset to start the process
on CPU 0, and then switching it to CPU 2 (ETF 1 is only reachable from
CPU 2):

taskset --cpu-list 0 ./perf record -e cs_etm/@tmc_etf1/ --per-thread -- taskset --cpu-list 2 ls

This produces a single 0 length AUX record, and then no more trace:

0x3c8 [0x30]: PERF_RECORD_AUX offset: 0 size: 0 flags: 0x1 [T]

After the fix, the same command produces normal AUX records. The perf
self test "89: Check Arm CoreSight trace data recording and synthesized
samples" no longer fails intermittently. This was because the taskset in
the test is after the fork, so there is a period where the task is
scheduled on a random CPU rather than forced to a valid one.

Specifically selecting an invalid CPU will still result in a failure to
open the event because it will never produce trace:

./perf record -C 2 -e cs_etm/@tmc_etf0/
failed to mmap with 12 (Cannot allocate memory)

The only scenario that has changed is if the CPU mask has a valid CPU
sink combo in it.

Testing
=======

* Coresight self test passes consistently:
./perf test Coresight

* CPU wide mode still produces trace:
./perf record -e cs_etm// -a

* Invalid -C options still fail to open:
./perf record -C 2,3 -e cs_etm/@tmc_etf0/
failed to mmap with 12 (Cannot allocate memory)

* Migrating a task to a valid sink/CPU now produces trace:
taskset --cpu-list 0 ./perf record -e cs_etm/@tmc_etf1/ --per-thread -- taskset --cpu-list 2 ls

* If the task remains on an invalid CPU, no trace is emitted:
taskset --cpu-list 0 ./perf record -e cs_etm/@tmc_etf1/ --per-thread -- ls

Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: James Clark <james.clark@arm.com>
Link: https://lore.kernel.org/r/20210922125144.133872-2-james.clark@arm.com
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>

coresight: etm-perf: Update to activate selected configuration

Add calls to activate the selected configuration as perf starts
and stops the tracing session.

Link: https://lore.kernel.org/r/20210723165444.1048-7-mike.leach@linaro.org
Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Mike Leach <mike.leach@linaro.org>
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Link: https://lore.kernel.org/r/20210818194022.379573-7-mathieu.poirier@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

coresight: etm-perf: Update to handle configuration selection

Loaded coresight configurations are registered in the cs_etm\events sub
directory. This extends the etm-perf code to handle these registrations,
and the cs_syscfg driver to perform the registration on load.

Link: https://lore.kernel.org/r/20210723165444.1048-5-mike.leach@linaro.org
Signed-off-by: Mike Leach <mike.leach@linaro.org>
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Link: https://lore.kernel.org/r/20210818194022.379573-5-mathieu.poirier@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

coresight: syscfg: Initial coresight system configuration

Creates an system management API to allow complex configurations and
features to be programmed into a CoreSight infrastructure.

A feature is defined as a programming set for a device or class of
devices.

A configuration is a set of features across the system that are enabled
for a trace session.

The API will manage system wide configuration, and allow complex
programmed features to be added to individual device instances, and
provide for system wide configuration selection on trace capture
operations.

This patch creates the initial data object and the initial API for
loading configurations and features.

Link: https://lore.kernel.org/r/20210723165444.1048-2-mike.leach@linaro.org
Signed-off-by: Mike Leach <mike.leach@linaro.org>
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Link: https://lore.kernel.org/r/20210818194022.379573-2-mathieu.poirier@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

coresight: etm-perf: Handle stale output handles

The context associated with an ETM for a given perf event
includes :
- handle -> the perf output handle for the AUX buffer.
- the path for the trace components
- the buffer config for the sink.

The path and the buffer config are part of the "aux_priv" data
(etm_event_data) setup by the setup_aux() callback, and made available
via perf_get_aux(handle).

Now with a sink supporting IRQ, the sink could "end" an output
handle when the buffer reaches the programmed limit and would try
to restart a handle. This could fail if there is not enough
space left the AUX buffer (e.g, the userspace has not consumed
the data). This leaves the "handle" disconnected from the "event"
and also the "perf_get_aux()" cleared. This all happens within
the sink driver, without the etm_perf driver being aware.
Now when the event is actually stopped, etm_event_stop()
will need to access the "event_data". But since the handle
is not valid anymore, we loose the information to stop the
"trace" path. So, we need a reliable way to access the etm_event_data
even when the handle may not be active.

This patch replaces the per_cpu handle array with a per_cpu context
for the ETM, which tracks the "handle" as well as the "etm_event_data".
The context notes the etm_event_data at etm_event_start() and clears
it at etm_event_stop(). This makes sure that we don't access a
stale "etm_event_data" as we are guaranteed that it is not
freed by free_aux() as long as the event is active and tracing,
also provides us with access to the critical information
needed to wind up a session even in the absence of an active
output_handle.

This is not an issue for the legacy sinks as none of them supports
an IRQ and is centrally handled by the etm-perf.

Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Anshuman Khandual <anshuman.khandual@arm.com>
Cc: Leo Yan <leo.yan@linaro.org>
Cc: Mike Leach <mike.leach@linaro.org>
Reviewed-by: Mike Leach <mike.leach@linaro.org>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Link: https://lore.kernel.org/r/20210405164307.1720226-16-suzuki.poulose@arm.com
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>

coresight: etm-perf: Allow an event to use different sinks

When a sink is not specified by the user, the etm perf driver
finds a suitable sink automatically, based on the first ETM
where this event could be scheduled. Then we allocate the
sink buffer based on the selected sink. This is fine for a
CPU bound event as the "sink" is always guaranteed to be
reachable from the ETM (as this is the only ETM where the
event is going to be scheduled). However, if we have a thread
bound event, the event could be scheduled on any of the ETMs
on the system. In this case, currently we automatically select
a sink and exclude any ETMs that cannot reach the selected
sink. This is problematic especially for 1x1 configurations.
We end up in tracing the event only on the "first" ETM,
as the default sink is local to the first ETM and unreachable
from the rest. However, we could allow the other ETMs to
trace if they all have a sink that is compatible with the
"selected" sink and can use the sink buffer. This can be
easily done by verifying that they are all driven by the
same driver and matches the same subtype. Please note
that at anytime there can be only one ETM tracing the event.

Adding support for different types of sinks for a single
event is complex and is not something that we expect
on a sane configuration.

Cc: Anshuman Khandual <anshuman.khandual@arm.com>
Reviewed-by: Mike Leach <mike.leach@linaro.org>
Tested-by: Linu Cherian <lcherian@marvell.com>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Link: https://lore.kernel.org/r/20210405164307.1720226-10-suzuki.poulose@arm.com
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>

coresight: etm-perf: Fix define build issue when built as module

CONFIG_CORESIGHT_SOURCE_ETM4X is undefined when built as module,
CONFIG_CORESIGHT_SOURCE_ETM4X_MODULE is defined instead.

Therefore code in format_attr_contextid_show() not correctly complied
when coresight built as module.

Use IS_ENABLED(CONFIG_CORESIGHT_SOURCE_ETM4X) to correct this.

Link: https://lore.kernel.org/r/20210414194808.22872-1-mike.leach@linaro.org
Fixes: 88f11864cf1d ("coresight: etm-perf: Support PID tracing for kernel at EL2")
Reviewed-by: Leo Yan <leo.yan@linaro.org>
Signed-off-by: Mike Leach <mike.leach@linaro.org>
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: stable <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20210415202404.945368-2-mathieu.poirier@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

coresight: etm: perf: Make symbol 'format_attr_contextid' static

The sparse tool complains as follows:

drivers/hwtracing/coresight/coresight-etm-perf.c:61:25: warning:
symbol 'format_attr_contextid' was not declared. Should it be static?

This symbol is not used outside of coresight-etm-perf.c, so this
commit marks it static.

Link: https://lore.kernel.org/r/20210308123250.2417947-1-weiyongjun1@huawei.com
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Link: https://lore.kernel.org/r/20210407160007.418053-3-mathieu.poirier@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

coresight: etm-perf: Support PID tracing for kernel at EL2

When the kernel is running at EL2, the PID is stored in CONTEXTIDR_EL2.
So, tracing CONTEXTIDR_EL1 doesn't give us the pid of the process.
Thus we should trace the VMID with VMIDOPT set to trace CONTEXTIDR_EL2
instead of CONTEXTIDR_EL1. Given that we have an existing config
option "contextid" and this will be useful for tracing virtual machines
(when we get to support virtualization).

So instead, this patch extends option CTXTID with an extra bit
ETM_OPT_CTXTID2 (bit 15), thus on an EL2 kernel, we will have another
bit available for the perf tool: ETM_OPT_CTXTID is for kernel running in
EL1, ETM_OPT_CTXTID2 is used when kernel runs in EL2 with VHE enabled.

The tool must be backward compatible for users, i.e, "contextid" today
traces PID and that should remain the same; for this purpose, the perf
tool is updated to automatically set corresponding bit for the
"contextid" config, therefore, the user doesn't have to bother which EL
the kernel is running.

i.e, perf record -e cs_etm/contextid/u --

will always do the "pid" tracing, independent of the kernel EL.

The driver parses the format "contextid", which traces CONTEXTIDR_EL1
for ETM_OPT_CTXTID (on EL1 kernel) and traces CONTEXTIDR_EL2 for
ETM_OPT_CTXTID2 (on EL2 kernel).

Besides the enhancement for format "contexid", extra two formats are
introduced: "contextid1" and "contextid2". This considers to support
tracing both CONTEXTIDR_EL1 and CONTEXTIDR_EL2 when the kernel is
running at EL2. Finally, the PMU formats are defined as follow:

"contextid1": Available on both EL1 kernel and EL2 kernel. When the
kernel is running at EL1, "contextid1" enables the PID
tracing; when the kernel is running at EL2, this enables
tracing the PID of guest applications.

"contextid2": Only usable when the kernel is running at EL2. When
selected, enables PID tracing on EL2 kernel.

"contextid": Will be an alias for the option that enables PID
tracing. I.e,
contextid == contextid1, on EL1 kernel.
contextid == contextid2, on EL2 kernel.

Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Al Grant <al.grant@arm.com>
Cc: Mike Leach <mike.leach@linaro.org>
Cc: Leo Yan <leo.yan@linaro.org>
Reviewed-by: Mike Leach <mike.leach@linaro.org>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
[ Added two config formats: contextid1, contextid2 ]
Signed-off-by: Leo Yan <leo.yan@linaro.org>
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Link: https://lore.kernel.org/r/20210206150833.42120-4-leo.yan@linaro.org
Link: https://lore.kernel.org/r/20210211172038.2483517-3-mathieu.poirier@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

coresight: etm-perf: Clarify comment on perf options

In theory, the options should be arbitrary values and are neutral for
any ETM version; so far perf tool uses ETMv3.5/PTM ETMCR config bits
except for register's bit definitions, also uses as options.

This can introduce confusion, especially if we want to add a new option
but the new option is not supported by ETMv3.5/PTM ETMCR. But on the
other hand, we cannot change options since these options are generic
CoreSight PMU ABI.

For easier maintenance and avoid confusion, this patch refines the
comment to clarify perf options, and gives out the background info for
these bits are coming from ETMv3.5/PTM. Afterwards, we should take
these options as general knobs, and if there have any confliction with
ETMv3.5/PTM, should consider to define saperate macros for ETMv3.5/PTM
ETMCR config bits.

Suggested-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Leo Yan <leo.yan@linaro.org>
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Link: https://lore.kernel.org/r/20210206150833.42120-2-leo.yan@linaro.org
Link: https://lore.kernel.org/r/20210211172038.2483517-2-mathieu.poirier@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

coresight: Fix uninitialised pointer bug in etm_setup_aux()

Commit [bb1860efc817] changed the sink handling code introducing an
uninitialised pointer bug. This results in the default sink selection
failing.

Prior to commit:

static void etm_setup_aux(...)

<snip>
struct coresight_device *sink;
<snip>

/* First get the selected sink from user space. */
if (event->attr.config2) {
id = (u32)event->attr.config2;
sink = coresight_get_sink_by_id(id);
} else {
sink = coresight_get_enabled_sink(true);
}
<ctd>

*sink always initialised - possibly to NULL which triggers the
automatic sink selection.

After commit:

static void etm_setup_aux(...)

<snip>
struct coresight_device *sink;
<snip>

/* First get the selected sink from user space. */
if (event->attr.config2) {
id = (u32)event->attr.config2;
sink = coresight_get_sink_by_id(id);
}
<ctd>

*sink pointer uninitialised when not providing a sink on the perf command
line. This breaks later checks to enable automatic sink selection.

Fixes: bb1860efc817 ("coresight: etm: perf: Sink selection using sysfs is deprecated")
Signed-off-by: Mike Leach <mike.leach@linaro.org>
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Link: https://lore.kernel.org/r/20201029164559.1268531-3-mathieu.poirier@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

coresight: core: Allow the coresight core driver to be built as a module

Enhance coresight developer's efficiency to debug coresight drivers.
- Kconfig becomes a tristate, to allow =m
- append -core to source file name to allow module to
be called coresight by the Makefile
- modules can have only one init/exit, so we add the etm_perf
register/unregister function calls to the core init/exit
functions.
- add a MODULE_DEVICE_TABLE for autoloading on boot

Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Leo Yan <leo.yan@linaro.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Suzuki K Poulose <Suzuki.Poulose@arm.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Russell King <linux@armlinux.org.uk>
Tested-by: Mike Leach <mike.leach@linaro.org>
Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Kim Phillips <kim.phillips@arm.com>
Signed-off-by: Tingwei Zhang <tingwei@codeaurora.org>
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Link: https://lore.kernel.org/r/20200928163513.70169-25-mathieu.poirier@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

coresight: etm: perf: Fix warning caused by etm_setup_aux failure

When coresight_build_path() fails on all the cpus, etm_setup_aux
calls etm_free_aux() to free allocated event_data.
WARN_ON(cpumask_empty(mask) will be triggered since cpu mask is empty.
Check event_data->snk_config is not NULL first to avoid this
warning.

Fixes: f5200aa9831f38 ("coresight: perf: Refactor function free_event_data()")
Reviewed-by: Mike Leach <mike.leach@linaro.org>
Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Tingwei Zhang <tingwei@codeaurora.org>
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Link: https://lore.kernel.org/r/20200928163513.70169-9-mathieu.poirier@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

coresight: Export global symbols

Export symbols used among coresight modules.

Tested-by: Mike Leach <mike.leach@linaro.org>
Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Mian Yousaf Kaukab <ykaukab@suse.de>
Signed-off-by: Tingwei Zhang <tingwei@codeaurora.org>
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Link: https://lore.kernel.org/r/20200928163513.70169-6-mathieu.poirier@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

coresight: etm: perf: Sink selection using sysfs is deprecated

When using the perf interface, sink selection using sysfs is
deprecated.

Signed-off-by: Linu Cherian <lcherian@marvell.com>
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Link: https://lore.kernel.org/r/20200916191737.4001561-14-mathieu.poirier@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

coresight: etm4x: Handle unreachable sink in perf mode

If the specified/hinted sink is not reachable from a subset of the CPUs,
we could end up unable to trace the event on those CPUs. This
is the best effort we could do until we support 1:1 configurations.
Fail gracefully in such cases avoiding a WARN_ON, which can be easily
triggered by the user on certain platforms (Arm N1SDP), with the following
trace paths :

CPU0
\
-- Funnel0 --> ETF0 -->
/ \
CPU1 \
MainFunnel
CPU2 /
\ /
-- Funnel1 --> ETF1 -->
/
CPU1

$ perf record --per-thread -e cs_etm/@ETF0/u -- <app>

could trigger the following WARNING, when the event is scheduled
on CPU2.

[10919.513250] ------------[ cut here ]------------
[10919.517861] WARNING: CPU: 2 PID: 24021 at
drivers/hwtracing/coresight/coresight-etm-perf.c:316 etm_event_start+0xf8/0x100
...

[10919.564403] CPU: 2 PID: 24021 Comm: perf Not tainted 5.8.0+ #24
[10919.570308] pstate: 80400089 (Nzcv daIf +PAN -UAO BTYPE=--)
[10919.575865] pc : etm_event_start+0xf8/0x100
[10919.580034] lr : etm_event_start+0x80/0x100
[10919.584202] sp : fffffe001932f940
[10919.587502] x29: fffffe001932f940 x28: fffffc834995f800
[10919.592799] x27: 0000000000000000 x26: fffffe0011f3ced0
[10919.598095] x25: fffffc837fce244c x24: fffffc837fce2448
[10919.603391] x23: 0000000000000002 x22: fffffc8353529c00
[10919.608688] x21: fffffc835bb31000 x20: 0000000000000000
[10919.613984] x19: fffffc837fcdcc70 x18: 0000000000000000
[10919.619281] x17: 0000000000000000 x16: 0000000000000000
[10919.624577] x15: 0000000000000000 x14: 00000000000009f8
[10919.629874] x13: 00000000000009f8 x12: 0000000000000018
[10919.635170] x11: 0000000000000000 x10: 0000000000000000
[10919.640467] x9 : fffffe00108cd168 x8 : 0000000000000000
[10919.645763] x7 : 0000000000000020 x6 : 0000000000000001
[10919.651059] x5 : 0000000000000002 x4 : 0000000000000001
[10919.656356] x3 : 0000000000000000 x2 : 0000000000000000
[10919.661652] x1 : fffffe836eb40000 x0 : 0000000000000000
[10919.666949] Call trace:
[10919.669382] etm_event_start+0xf8/0x100
[10919.673203] etm_event_add+0x40/0x60
[10919.676765] event_sched_in.isra.134+0xcc/0x210
[10919.681281] merge_sched_in+0xb0/0x2a8
[10919.685017] visit_groups_merge.constprop.140+0x15c/0x4b8
[10919.690400] ctx_sched_in+0x15c/0x170
[10919.694048] perf_event_sched_in+0x6c/0xa0
[10919.698130] ctx_resched+0x60/0xa0
[10919.701517] perf_event_exec+0x288/0x2f0
[10919.705425] begin_new_exec+0x4c8/0xf58
[10919.709247] load_elf_binary+0x66c/0xf30
[10919.713155] exec_binprm+0x15c/0x450
[10919.716716] __do_execve_file+0x508/0x748
[10919.720711] __arm64_sys_execve+0x40/0x50
[10919.724707] do_el0_svc+0xf4/0x1b8
[10919.728095] el0_sync_handler+0xf8/0x124
[10919.732003] el0_sync+0x140/0x180

Even though we don't support using separate sinks for the ETMs yet (e.g,
for 1:1 configurations), we should at least honor the user's choice and
handle the limitations gracefully, by simply skipping the tracing on ETMs
which can't reach the requested sink.

Fixes: f9d81a657bb8 ("coresight: perf: Allow tracing on hotplugged CPUs")
Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Mike Leach <mike.leach@linaro.org>
Reported-by: Jeremy Linton <jeremy.linton@arm.com>
Tested-by: Jeremy Linton <jeremy.linton@arm.com>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Link: https://lore.kernel.org/r/20200916191737.4001561-11-mathieu.poirier@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

coresight: etm: perf: Add default sink selection to etm perf

Add default sink selection to the perf trace handling in the etm driver.
Uses the select default sink infrastructure to select a sink for the perf
session, if no other sink is specified.

Signed-off-by: Mike Leach <mike.leach@linaro.org>
Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Link: https://lore.kernel.org/r/20200716175746.3338735-17-mathieu.poirier@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

coresight: Fix DEBUG_LOCKS_WARN_ON for uninitialized attribute

While running the linux-next with CONFIG_DEBUG_LOCKS_ALLOC enabled,
I get the following splat.

BUG: key ffffcb5636929298 has not been registered!
------------[ cut here ]------------
DEBUG_LOCKS_WARN_ON(1)
WARNING: CPU: 1 PID: 53 at kernel/locking/lockdep.c:3669 lockdep_init_map+0x164/0x1f0
CPU: 1 PID: 53 Comm: kworker/1:1 Tainted: G W 5.2.0-next-20190712-00015-g00ad4634222e-dirty #603
Workqueue: events amba_deferred_retry_func
pstate: 60c00005 (nZCv daif +PAN +UAO)
pc : lockdep_init_map+0x164/0x1f0
lr : lockdep_init_map+0x164/0x1f0

[ trimmed ]

Call trace:
lockdep_init_map+0x164/0x1f0
__kernfs_create_file+0x9c/0x158
sysfs_add_file_mode_ns+0xa8/0x1d0
sysfs_add_file_to_group+0x88/0xd8
etm_perf_add_symlink_sink+0xcc/0x138
coresight_register+0x110/0x280
tmc_probe+0x160/0x420

[ trimmed ]

---[ end trace ab4cc669615ba1b0 ]---

Fix this by initialising the dynamically allocated attribute properly.

Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Fixes: bb8e370bdc14 ("coresight: perf: Add "sinks" group to PMU directory")
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
[Fixed a typograhic error in the changelog]
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Link: https://lore.kernel.org/r/20190801172323.18359-2-mathieu.poirier@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

coresight: Use coresight device names for sinks in PMU attribute

Move to using the coresight device name instead of the parent
device name for SINK attribute for PMU.

Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

coresight: Communicate perf event to sink buffer allocation functions

Make struct perf_event available to sink buffer allocation functions in
order to use the pid they carry to allocate and free buffer memory along
with regimenting access to what source a sink can collect data for.

Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Tested-by: Leo Yan <leo.yan@linaro.org>
Tested-by: Robert Walker <robert.walker@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

coresight: perf: Refactor function free_event_data()

Function free_event_data() is already busy and is bound to become
worse with the addition of CPU-wide trace scenarios. As such spin
off a new function to strickly take care of the sink buffers.

Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Tested-by: Leo Yan <leo.yan@linaro.org>
Tested-by: Robert Walker <robert.walker@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

coresight: perf: Clean up function etm_setup_aux()

There is no point in allocating sink memory for a trace session if
there is not a way to free it once it is no longer needed. As such make
sure the sink API function to allocate and free memory have been
implemented before moving ahead with the establishment of a trace
session.

Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Tested-by: Leo Yan <leo.yan@linaro.org>
Tested-by: Robert Walker <robert.walker@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

coresight: etm4x: Add kernel configuration for CONTEXTID

Set the proper bit in the configuration register when contextID tracing
has been requested by user space. That way PE_CONTEXT elements are
generated by the tracers when a process is installed on a CPU.

Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Tested-by: Leo Yan <leo.yan@linaro.org>
Tested-by: Robert Walker <robert.walker@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

coresight: pmu: Adding ITRACE property to cs_etm PMU

Add to the capabilities the ITRACE property so that ITRACE START events
are generated when the PMU is switched on by the core.

Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Acked-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Tested-by: Leo Yan <leo.yan@linaro.org>
Tested-by: Robert Walker <robert.walker@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

perf, pt, coresight: Fix address filters for vmas with non-zero offset

Currently, the address range calculation for file-based filters works as
long as the vma that maps the matching part of the object file starts
from offset zero into the file (vm_pgoff==0). Otherwise, the resulting
filter range would be off by vm_pgoff pages. Another related problem is
that in case of a partially matching vma, that is, a vma that matches
part of a filter region, the filter range size wouldn't be adjusted.

Fix the arithmetics around address filter range calculations, taking
into account vma offset, so that the entire calculation is done before
the filter configuration is passed to the PMU drivers instead of having
those drivers do the final bit of arithmetics.

Based on the patch by Adrian Hunter <adrian.hunter.intel.com>.

Reported-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Tested-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Fixes: 375637bc5249 ("perf/core: Introduce address range filtering")
Link: http://lkml.kernel.org/r/20190215115655.63469-3-alexander.shishkin@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

coresight: Use event attributes for sink selection

This patch uses the information conveyed by perf_event::attr::config2
to select a sink to use for the session. That way a sink can easily be
selected to be used by more than one source, something that isn't currently
possible with the sysfs implementation.

Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

coresight: perf: Add "sinks" group to PMU directory

Add a "sinks" directory entry so that users can see all the sinks
available in the system in a single place. Individual sink are added
as they are registered with the coresight bus.

Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

perf/aux: Make perf_event accessible to setup_aux()

When pmu::setup_aux() is called the coresight PMU needs to know which
sink to use for the session by looking up the information in the
event's attr::config2 field.

As such simply replace the cpu information by the complete perf_event
structure and change all affected customers.

Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

coresight: Use event attributes for sink selection

This patch uses the information conveyed by perf_event::attr::config2
to select a sink to use for the session. That way a sink can easily be
selected to be used by more than one source, something that isn't currently
possible with the sysfs implementation.

Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will.deacon@arm.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-s390@vger.kernel.org
Link: http://lkml.kernel.org/r/20190131184714.20388-4-mathieu.poirier@linaro.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

coresight: perf: Add "sinks" group to PMU directory

Add a "sinks" directory entry so that users can see all the sinks
available in the system in a single place. Individual sink are added
as they are registered with the coresight bus.

Committer tests:

Test built on a ubuntu 18.04 container with a cross build environment to
arm64, the new field is there, need to find a machine with this feature
to do further testing in the future.

root@d15263e5734a:/git/perf# grep CORESIGHT /tmp/build/v5.0-rc2+/.config
CONFIG_CORESIGHT=y
CONFIG_CORESIGHT_LINKS_AND_SINKS=y
CONFIG_CORESIGHT_LINK_AND_SINK_TMC=y
CONFIG_CORESIGHT_CATU=y
CONFIG_CORESIGHT_SINK_TPIU=y
CONFIG_CORESIGHT_SINK_ETBV10=y
CONFIG_CORESIGHT_SOURCE_ETM4X=y
CONFIG_CORESIGHT_DYNAMIC_REPLICATOR=y
CONFIG_CORESIGHT_STM=y
CONFIG_CORESIGHT_CPU_DEBUG=m
root@d15263e5734a:/git/perf#
root@d15263e5734a:/git/perf# file /tmp/build/v5.0-rc2+/drivers/hwtracing/coresight/*.o
.../coresight/coresight-catu.o: ELF 64-bit MSB relocatable, ARM aarch64, version 1 (SYSV), not stripped
.../coresight/coresight-cpu-debug.mod.o: ELF 64-bit MSB relocatable, ARM aarch64, version 1 (SYSV), not stripped
.../coresight/coresight-cpu-debug.o: ELF 64-bit MSB relocatable, ARM aarch64, version 1 (SYSV), not stripped
.../coresight/coresight-dynamic-replicator.o: ELF 64-bit MSB relocatable, ARM aarch64, version 1 (SYSV), not stripped
.../coresight/coresight-etb10.o: ELF 64-bit MSB relocatable, ARM aarch64, version 1 (SYSV), not stripped
.../coresight/coresight-etm-perf.o: ELF 64-bit MSB relocatable, ARM aarch64, version 1 (SYSV), not stripped
.../coresight/coresight-etm4x-sysfs.o: ELF 64-bit MSB relocatable, ARM aarch64, version 1 (SYSV), not stripped
.../coresight/coresight-etm4x.o: ELF 64-bit MSB relocatable, ARM aarch64, version 1 (SYSV), not stripped
.../coresight/coresight-funnel.o: ELF 64-bit MSB relocatable, ARM aarch64, version 1 (SYSV), not stripped
.../coresight/coresight-replicator.o: ELF 64-bit MSB relocatable, ARM aarch64, version 1 (SYSV), not stripped
.../coresight/coresight-stm.o: ELF 64-bit MSB relocatable, ARM aarch64, version 1 (SYSV), not stripped
.../coresight/coresight-tmc-etf.o: ELF 64-bit MSB relocatable, ARM aarch64, version 1 (SYSV), not stripped
.../coresight/coresight-tmc-etr.o: ELF 64-bit MSB relocatable, ARM aarch64, version 1 (SYSV), not stripped
.../coresight/coresight-tmc.o: ELF 64-bit MSB relocatable, ARM aarch64, version 1 (SYSV), not stripped
.../coresight/coresight-tpiu.o: ELF 64-bit MSB relocatable, ARM aarch64, version 1 (SYSV), not stripped
.../coresight/coresight.o: ELF 64-bit MSB relocatable, ARM aarch64, version 1 (SYSV), not stripped
.../coresight/of_coresight.o: ELF 64-bit MSB relocatable, ARM aarch64, version 1 (SYSV), not stripped
root@d15263e5734a:/git/perf#

root@d15263e5734a:/git/perf# pahole -C coresight_device /tmp/build/v5.0-rc2+/drivers/hwtracing/coresight/coresight.o
struct coresight_device {
struct coresight_connection * conns; /* 0 8 */
int nr_inport; /* 8 4 */
int nr_outport; /* 12 4 */
enum coresight_dev_type type; /* 16 4 */
union coresight_dev_subtype subtype; /* 20 8 */

/* XXX 4 bytes hole, try to pack */

const struct coresight_ops * ops; /* 32 8 */
struct device dev; /* 40 1408 */

/* XXX last struct has 7 bytes of padding */

/* --- cacheline 22 boundary (1408 bytes) was 40 bytes ago --- */
atomic_t * refcnt; /* 1448 8 */
bool orphan; /* 1456 1 */
bool enable; /* 1457 1 */
bool activated; /* 1458 1 */

/* XXX 5 bytes hole, try to pack */

struct dev_ext_attribute * ea; /* 1464 8 */

/* size: 1472, cachelines: 23, members: 12 */
/* sum members: 1463, holes: 2, sum holes: 9 */
/* paddings: 1, sum paddings: 7 */
};
root@d15263e5734a:/git/perf#

Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will.deacon@arm.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-s390@vger.kernel.org
Link: http://lkml.kernel.org/r/20190131184714.20388-3-mathieu.poirier@linaro.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

perf/aux: Make perf_event accessible to setup_aux()

When pmu::setup_aux() is called the coresight PMU needs to know which
sink to use for the session by looking up the information in the
event's attr::config2 field.

As such simply replace the cpu information by the complete perf_event
structure and change all affected customers.

Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Reviewed-by: Suzuki Poulouse <suzuki.poulose@arm.com>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will.deacon@arm.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-s390@vger.kernel.org
Link: http://lkml.kernel.org/r/20190131184714.20388-2-mathieu.poirier@linaro.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

coresight: perf: Remove set_buffer call back

In coresight perf mode, we need to prepare the sink before
starting a session, which is done via set_buffer call back.
We then proceed to enable the tracing. If we fail to start
the session successfully, we leave the sink configuration
unchanged. In order to make the operation atomic and to
avoid yet another call back to clear the buffer, we get
rid of the "set_buffer" call back and pass the buffer details
via enable() call back to the sink.

Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

coresight: perf: Add helper to retrieve sink configuration

We can always find the sink configuration for a given perf_output_handle.
Add a helper to retrieve the sink configuration for a given
perf_output_handle. This will be used to get rid of the set_buffer()
call back.

Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

coresight: perf: Remove reset_buffer call back for sinks

Right now we issue an update_buffer() and reset_buffer() call backs
in succession when we stop tracing an event. The update_buffer is
supposed to check the status of the buffer and make sure the ring buffer
is updated with the trace data. And we store information about the
size of the data collected only to be consumed by the reset_buffer
callback which always follows the update_buffer. This was originally
designed for handling future IPs which could trigger a buffer overflow
interrupt. This patch gets rid of the reset_buffer callback altogether
and performs the actions in update_buffer, making it return the size
collected. We can always add the support for handling the overflow
interrupt case later.

This removes some not-so pretty hack (storing the new head in the
size field for snapshot mode) and cleans it up a little bit.

Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

coresight: perf: Disable trace path upon source error

We enable the trace path, before activating the source.
If we fail to enable the source, we must disable the path
to make sure it is available for another session.

Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

coresight: perf: Allow tracing on hotplugged CPUs

At the moment, if there is no CPU specified for a given
event, we use cpu_online_mask and try to build path for
each of the CPUs in the mask. This could prevent any CPU
that is turned online later to be used for the tracing.

This patch changes to use the cpu_present_mask and tries
to build path for as much CPUs as possible ignoring the
failures in building path for some of the CPUs. If ever
we try to trace on those CPUs, we fail the operation.

Based on a patch from Mathieu Poirier.

Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

coresight: perf: Avoid unncessary CPU hotplug read lock

We hold the read lock on CPU hotplug to simply copy the
online mask, which is not really needed. And this can
cause a lockdep warning, like :

[ 54.632093] ======================================================
[ 54.638207] WARNING: possible circular locking dependency detected
[ 54.644322] 4.18.0-rc3-00042-g2d39e6356bb7-dirty #309 Not tainted
[ 54.650350] ------------------------------------------------------
[ 54.656464] perf/2862 is trying to acquire lock:
[ 54.661031] 000000007e21d170 (&event->mmap_mutex){+.+.}, at: perf_event_set_output+0x98/0x138
[ 54.669486]
[ 54.669486] but task is already holding lock:
[ 54.675256] 000000001080eb1b (&cpuctx_mutex){+.+.}, at: perf_event_ctx_lock_nested+0xf8/0x1f0
[ 54.683704]
[ 54.683704] which lock already depends on the new lock.
[ 54.683704]
[ 54.691797]
[ 54.691797] the existing dependency chain (in reverse order) is:
[ 54.699201]
[ 54.699201] -> #3 (&cpuctx_mutex){+.+.}:
[ 54.704556] __mutex_lock+0x70/0x808
[ 54.708608] mutex_lock_nested+0x1c/0x28
[ 54.713005] perf_event_init_cpu+0x8c/0xd8
[ 54.717574] perf_event_init+0x194/0x1d4
[ 54.721971] start_kernel+0x2b8/0x42c
[ 54.726107]
[ 54.726107] -> #2 (pmus_lock){+.+.}:
[ 54.731114] __mutex_lock+0x70/0x808
[ 54.735165] mutex_lock_nested+0x1c/0x28
[ 54.739560] perf_event_init_cpu+0x30/0xd8
[ 54.744129] cpuhp_invoke_callback+0x84/0x248
[ 54.748954] _cpu_up+0xe8/0x1c8
[ 54.752576] do_cpu_up+0xa8/0xc8
[ 54.756283] cpu_up+0x10/0x18
[ 54.759731] smp_init+0xa0/0x114
[ 54.763438] kernel_init_freeable+0x120/0x288
[ 54.768264] kernel_init+0x10/0x108
[ 54.772230] ret_from_fork+0x10/0x18
[ 54.776279]
[ 54.776279] -> #1 (cpu_hotplug_lock.rw_sem){++++}:
[ 54.782492] cpus_read_lock+0x34/0xb0
[ 54.786631] etm_setup_aux+0x5c/0x308
[ 54.790769] rb_alloc_aux+0x1ec/0x300
[ 54.794906] perf_mmap+0x284/0x610
[ 54.798787] mmap_region+0x388/0x570
[ 54.802838] do_mmap+0x344/0x4f8
[ 54.806544] vm_mmap_pgoff+0xe4/0x110
[ 54.810682] ksys_mmap_pgoff+0xa8/0x240
[ 54.814992] sys_mmap+0x18/0x28
[ 54.818613] el0_svc_naked+0x30/0x34
[ 54.822661]
[ 54.822661] -> #0 (&event->mmap_mutex){+.+.}:
[ 54.828445] lock_acquire+0x48/0x68
[ 54.832409] __mutex_lock+0x70/0x808
[ 54.836459] mutex_lock_nested+0x1c/0x28
[ 54.840855] perf_event_set_output+0x98/0x138
[ 54.845680] _perf_ioctl+0x2a0/0x6a0
[ 54.849731] perf_ioctl+0x3c/0x68
[ 54.853526] do_vfs_ioctl+0xb8/0xa20
[ 54.857577] ksys_ioctl+0x80/0xb8
[ 54.861370] sys_ioctl+0xc/0x18
[ 54.864990] el0_svc_naked+0x30/0x34
[ 54.869039]
[ 54.869039] other info that might help us debug this:
[ 54.869039]
[ 54.876960] Chain exists of:
[ 54.876960] &event->mmap_mutex --> pmus_lock --> &cpuctx_mutex
[ 54.876960]
[ 54.887217] Possible unsafe locking scenario:
[ 54.887217]
[ 54.893073] CPU0 CPU1
[ 54.897552] ---- ----
[ 54.902030] lock(&cpuctx_mutex);
[ 54.905396] lock(pmus_lock);
[ 54.910911] lock(&cpuctx_mutex);
[ 54.916770] lock(&event->mmap_mutex);
[ 54.920566]
[ 54.920566] *** DEADLOCK ***
[ 54.920566]
[ 54.926424] 1 lock held by perf/2862:
[ 54.930042] #0: 000000001080eb1b (&cpuctx_mutex){+.+.}, at: perf_event_ctx_lock_nested+0xf8/0x1f0

Since we have per-cpu array for the paths, we simply don't care about
the number of online CPUs. This patch gets rid of the
{get/put}_online_cpus().

Reported-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

coresight: perf: Fix per cpu path management

We create a coresight trace path for each online CPU when
we start the event. We rely on the number of online CPUs
and then go on to allocate an array matching the "number of
online CPUs" for holding the path and then uses normal
CPU id as the index to the array. This is problematic as
we could have some offline CPUs causing us to access beyond
the actual array size (e.g, on a dual SMP system, if CPU0 is
offline, CPU1 could be really accessing beyond the array).
The solution is to switch to per-cpu array for holding the path.

Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

coresight: Moving framework and drivers to SPDX identifier

Moving all kernel side CoreSight framework and drivers to SPDX identifier.

Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

perf/x86/pt, coresight: Clean up address filter structure

This is a cosmetic patch that deals with the address filter structure's
ambiguous fields 'filter' and 'range'. The former stands to mean that the
filter's *action* should be to filter the traces to its address range if
it's set or stop tracing if it's unset. This is confusing and hard on the
eyes, so this patch replaces it with 'action' enum. The 'range' field is
completely redundant (meaning that the filter is an address range as
opposed to a single address trigger), as we can use zero size to mean the
same thing.

Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Acked-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Cc: Will Deacon <will.deacon@arm.com>
Link: http://lkml.kernel.org/r/20180329120648.11902-1-alexander.shishkin@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>

coresight: pmu: Adds return stack option to perf coresight pmu

Return stack is a programmable option on some ETM and PTM hardware.
Adds the option flags to enable this from the perf event command line.

Signed-off-by: Mike Leach <mike.leach@linaro.org>
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

hwtracing: coresight: constify attribute_group structures.

attribute_groups are not supposed to change at runtime. All functions
working with attribute_groups provided by <linux/sysfs.h> work with const
attribute_group. So mark the non-const structs as const.

File size before:
text data bss dec hex filename
2573 288 296 3157 c55 coresight-etm-perf.o

File size After adding 'const':
text data bss dec hex filename
2613 224 296 3133 c3d coresight-etm-perf.o

Signed-off-by: Arvind Yadav <arvind.yadav.cs@gmail.com>
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

coresight: etm_perf: Fix using uninitialised work

With 4.11-rc4, the following command triggers a WARN_ON,
when a sink is not enabled.

perf record -e cs_etm/@20010000.etf/

[88286.547741] ------------[ cut here ]------------
[88286.552332] WARNING: CPU: 3 PID: 2156 at kernel/workqueue.c:1442 __queue_work+0x29c/0x3b8
[88286.560427] Modules linked in:
[88286.563451]
[88286.564928] CPU: 3 PID: 2156 Comm: perf_v4.11 Not tainted 4.11.0-rc4 #217
[88286.573453] Hardware name: ARM LTD ARM Juno Development Platform/ARM Juno Development Platform, BIOS EDK II Aug 15
2016
[88286.584128] task: ffff80097597c200 task.stack: ffff8009768b0000
[88286.589990] PC is at __queue_work+0x29c/0x3b8
[88286.594303] LR is at __queue_work+0x104/0x3b8
[88286.598614] pc : [<ffff0000080d8c7c>] lr : [<ffff0000080d8ae4>] pstate: a00001c5
[88286.605934] sp : ffff8009768b3aa0
[88286.609212] x29: ffff8009768b3aa0 x28: ffff80097ff3da00
[88286.614477] x27: ffff80097ff89c00 x26: ffff8009751b0e00
[88286.619741] x25: ffff000008c9f000 x24: 0000000000000003
[88286.625004] x23: 0000000000000040 x22: ffff000008d3dab8
[88286.630268] x21: ffff800977804400 x20: 0000000000000007
[88286.635532] x19: ffff000008c54000 x18: 0000fffff9185160
[88286.640795] x17: 0000ffffb33d9a38 x16: ffff000008088270
[88286.646059] x15: 0000ffffb345b590 x14: 0000000000000000
[88286.651322] x13: 0000000000000004 x12: 0000000000000040
[88286.656586] x11: 0000000000000068 x10: 0000000000000000
[88286.661849] x9 : ffff800977400028 x8 : 0000000000000000
[88286.667113] x7 : 0000000000000000 x6 : ffff0000080d8ae4
[88286.672376] x5 : 0000000000000000 x4 : 0000000000000080
[88286.677639] x3 : 0000000000000000 x2 : 0000000000000000
[88286.682903] x1 : 0000000000000000 x0 : ffff8009751b0e08
[88286.688166]
[88286.689638] ---[ end trace 31633f18fd33d4cb ]---
[88286.694206] Call trace:
[88286.696627] Exception stack(0xffff8009768b38d0 to 0xffff8009768b3a00)
[88286.703004] 38c0: ffff000008c54000 0001000000000000
[88286.710757] 38e0: ffff8009768b3aa0 ffff0000080d8c7c ffff8009768b3b50 ffff80097ff8a5b0
[88286.718511] 3900: 0000800977325000 0000000000000000 0000000000000040 ffff80097ffc6180
[88286.726264] 3920: ffff8009768b3940 ffff0000088a8694 ffff80097ffc5800 0000000000000000
[88286.734017] 3940: ffff8009768b3960 ffff0000081919c0 ffff80097ffc5280 0000000000000001
[88286.741771] 3960: ffff8009768b3a50 ffff00000819206c ffff8009751b0e08 0000000000000000
[88286.749523] 3980: 0000000000000000 0000000000000000 0000000000000080 0000000000000000
[88286.757277] 39a0: ffff0000080d8ae4 0000000000000000 0000000000000000 ffff800977400028
[88286.765029] 39c0: 0000000000000000 0000000000000068 0000000000000040 0000000000000004
[88286.772783] 39e0: 0000000000000000 0000ffffb345b590 ffff000008088270 0000ffffb33d9a38
[88286.780537] [<ffff0000080d8c7c>] __queue_work+0x29c/0x3b8
[88286.785883] [<ffff0000080d8df8>] queue_work_on+0x60/0x78
[88286.791146] [<ffff000008764c68>] etm_setup_aux+0x178/0x238
[88286.796578] [<ffff000008183600>] rb_alloc_aux+0x228/0x310
[88286.801925] [<ffff00000817e564>] perf_mmap+0x404/0x5a8
[88286.807015] [<ffff0000081c60cc>] mmap_region+0x394/0x5c0
[88286.812276] [<ffff0000081c654c>] do_mmap+0x254/0x388
[88286.817191] [<ffff0000081a989c>] vm_mmap_pgoff+0xbc/0xe0
[88286.822452] [<ffff0000081c3ffc>] SyS_mmap_pgoff+0xac/0x228
[88286.827884] [<ffff000008088288>] sys_mmap+0x18/0x28
[88286.832714] [<ffff000008082f30>] el0_svc_naked+0x24/0x28

The patch makes sure that the event_data->work is initialised
properly before we could possibly use it.

Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Tested-by: Mike Leach <mike.leach@linaro.org>
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

perf/core: Keep AUX flags in the output handle

In preparation for adding more flags to perf AUX records, introduce a
separate API for setting the flags for a session, rather than appending
more bool arguments to perf_aux_output_end. This allows to set each
flag at the time a corresponding condition is detected, instead of
tracking it in each driver's private state.

Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mathieu Poirier <mathieu.poirier@linaro.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>
Cc: vince@deater.net
Link: http://lkml.kernel.org/r/20170220133352.17995-3-alexander.shishkin@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>

coresight: fix kernel panic caused by invalid CPU

Commit d52c9750f150 ("coresight: reset "enable_sink" flag when need be")
caused a kernel panic because of the using of an invalid value: after
'for_each_cpu(cpu, mask)', value of local variable 'cpu' become invalid,
causes following 'cpu_to_node' access invalid memory area.

This patch brings the deleted 'cpu = cpumask_first(mask)' back.

Panic log:

$ perf record -e cs_etm// ls

Unable to handle kernel paging request at virtual address fffe801804af4f10
pgd = ffff8017ce031600
[fffe801804af4f10] *pgd=0000000000000000, *pud=0000000000000000
Internal error: Oops: 96000004 [#1] SMP
Modules linked in:
CPU: 33 PID: 1619 Comm: perf Not tainted 4.7.1+ #16
Hardware name: Huawei Taishan 2280 /CH05TEVBA, BIOS 1.10 11/24/2016
task: ffff8017cb0c8400 ti: ffff8017cb154000 task.ti: ffff8017cb154000
PC is at tmc_alloc_etf_buffer+0x60/0xd4
LR is at tmc_alloc_etf_buffer+0x44/0xd4
pc : [<ffff000008633df8>] lr : [<ffff000008633ddc>] pstate: 60000145
sp : ffff8017cb157b40
x29: ffff8017cb157b40 x28: 0000000000000000
...skip...
7a60: ffff000008c64dc8 0000000000000006 0000000000000253 ffffffffffffffff
7a80: 0000000000000000 0000000000000000 ffff0000080872cc 0000000000000001
[<ffff000008633df8>] tmc_alloc_etf_buffer+0x60/0xd4
[<ffff000008632b9c>] etm_setup_aux+0x1dc/0x1e8
[<ffff00000816eed4>] rb_alloc_aux+0x2b0/0x338
[<ffff00000816a5e4>] perf_mmap+0x414/0x568
[<ffff0000081ab694>] mmap_region+0x324/0x544
[<ffff0000081abbe8>] do_mmap+0x334/0x3e0
[<ffff000008191150>] vm_mmap_pgoff+0xa4/0xc8
[<ffff0000081a9a30>] SyS_mmap_pgoff+0xb0/0x22c
[<ffff0000080872e4>] sys_mmap+0x18/0x28
[<ffff0000080843f0>] el0_svc_naked+0x24/0x28
Code: 912040a5 d0001c00 f873d821 911c6000 (b8656822)
---[ end trace 98933da8f92b0c9a ]---

Signed-off-by: Wang Nan <wangnan0@huawei.com>
Cc: Xia Kaixu <xiakaixu@huawei.com>
Cc: Li Zefan <lizefan@huawei.com>
Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-kernel@vger.kernel.org
Fixes: d52c9750f150 ("coresight: reset "enable_sink" flag when need be")
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: stable <stable@vger.kernel.org> # 4.10
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

coresight: perf: Add a missing call to etm_free_aux

Most error branches following the call to alloc_event_data contain a call
to etm_free_aux. This patch add a call to etm_free_aux to an error branch
that does not call it.

This issue was found with Hector.

Signed-off-by: Quentin Lambert <lambert.quentin@gmail.com>
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

coresight: reset "enable_sink" flag when need be

When using coresight from the perf interface sinks are specified
as part of the perf command line. As such the sink needs to be
disabled once it has been acknowledged by the coresight framework.
Otherwise the sink stays enabled, which may interfere with other
sessions.

This patch removes the sink selection check from the build path
process and make it a function on it's own. The function is
then used when operating from sysFS or perf to determine what
sink has been selected.

If operated from perf the status of the "enable_sink" flag is
reset so that concurrent session can use a different sink. When
used from sysFS the status of the flag is left untouched since
users have full control.

The implementation doesn't handle a scenario where a sink has
been enabled from sysFS and another sink is selected from the
perf command line as both modes of operation are mutually
exclusive.

Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

coresight: perf: deal with error condition properly

Function coresight_build_path() should return -ENOMEM when kzalloc
fails to allocated the requested memory. That way callers can deal
with the error condition in a similar way.

Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

coresight: etm-perf: configuring filters from perf core

This patch implements the required API needed to access
and retrieve range and start/stop filters from the perf core.

Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

coresight: etm-perf: pass struct perf_event to source::enable/disable()

With this commit [1] address range filter information is now found
in the struct hw_perf_event::addr_filters. As such pass the event
itself to the coresight_source::enable/disable() functions so that
both event attribute and filter can be accessible for configuration.

[1] 'commit 375637bc5249 ("perf/core: Introduce address range filtering")'

Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/hwtracing: make coresight-etm-perf.c explicitly non-modular

In commit 941943cf519f7cacbbcecee5c4ef4b77b466bd5c ("drivers/hwtracing:
make coresight-* explicitly non-modular") we removed all uses of
modular functions/macros in favour of their built-in equivlents in
this subsystem.

However that commit and commit 0bcbf2e30ff2271b54f54c8697a185f7d86ec6e4
("coresight: etm-perf: new PMU driver for ETM tracers") were in flight
at the same time, and hence one new non-modular user of module_init
crept back in. Fix it up like we did all the others.

Since module_init translates to device_initcall in the non-modular
case, the init ordering remains unchanged with this commit.

Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Acked-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

coresight: etm-perf: new PMU driver for ETM tracers

Perf is a well known and used tool for performance monitoring
and much more. A such it is an ideal candidate for integration
with coresight based HW tracing.

This patch introduces a PMU that represent a coresight tracer to
the Perf core.

Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>