The source device can directly read the trace ID from the coresight_path
which result in etm_read_alloc_trace_id and etm4_read_alloc_trace_id being
deleted.
Co-developed-by: James Clark <james.clark@linaro.org>
Signed-off-by: James Clark <james.clark@linaro.org>
Signed-off-by: Jie Gan <quic_jiegan@quicinc.com>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Link: https://lore.kernel.org/r/20250303032931.2500935-7-quic_jiegan@quicinc.com
Add 'trace_id' function pointer in coresight_ops. It's responsible for retrieving
the device's trace ID.
Co-developed-by: James Clark <james.clark@linaro.org>
Signed-off-by: James Clark <james.clark@linaro.org>
Reviewed-by: James Clark <james.clark@linaro.org>
Signed-off-by: Jie Gan <quic_jiegan@quicinc.com>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Link: https://lore.kernel.org/r/20250303032931.2500935-3-quic_jiegan@quicinc.com
Some dummy source has static trace id configured in HW and it cannot
be changed via software programming. Configure the trace id in device
tree and reserve the id when device probe.
Signed-off-by: Mao Jinlong <quic_jinlmao@quicinc.com>
Link: https://lore.kernel.org/r/20241121062829.11571-4-quic_jinlmao@quicinc.com
[ Fix Date and Version to December 2024, v6.14 ]
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
The continual trickle of small conversion patches is grating on me, and
is really not helping. Just get rid of the 'remove_new' member
function, which is just an alias for the plain 'remove', and had a
comment to that effect:
/*
* .remove_new() is a relic from a prototype conversion of .remove().
* New drivers are supposed to implement .remove(). Once all drivers are
* converted to not use .remove_new any more, it will be dropped.
*/
This was just a tree-wide 'sed' script that replaced '.remove_new' with
'.remove', with some care taken to turn a subsequent tab into two tabs
to make things line up.
I did do some minimal manual whitespace adjustment for places that used
spaces to line things up.
Then I just removed the old (sic) .remove_new member function, and this
is the end result. No more unnecessary conversion noise.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This will allow sessions with more than CORESIGHT_TRACE_IDS_MAX ETMs
as long as there are fewer than that many ETMs connected to each sink.
Each sink owns its own trace ID map, and any Perf session connecting to
that sink will allocate from it, even if the sink is currently in use by
other users. This is similar to the existing behavior where the dynamic
trace IDs are constant as long as there is any concurrent Perf session
active. It's not completely optimal because slightly more IDs will be
used than necessary, but the optimal solution involves tracking the PIDs
of each session and allocating ID maps based on the session owner. This
is difficult to do with the combination of per-thread and per-cpu modes
and some scheduling issues. The complexity of this isn't likely to worth
it because even with multiple users they'd just see a difference in the
ordering of ID allocations rather than hitting any limits (unless the
hardware does have too many ETMs connected to one sink).
Signed-off-by: James Clark <james.clark@arm.com>
Reviewed-by: Mike Leach <mike.leach@linaro.org>
Signed-off-by: James Clark <james.clark@linaro.org>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Link: https://lore.kernel.org/r/20240722101202.26915-15-james.clark@linaro.org
The coresight_disable_source_sysfs function should verify the
mode of the coresight device before disabling the source.
However, the mode for the dummy source device is always set to
CS_MODE_DISABLED, resulting in the check consistently failing.
As a result, dummy source cannot be properly disabled.
Configure CS_MODE_SYSFS/CS_MODE_PERF during the enablement.
Configure CS_MODE_DISABLED during the disablement.
Fixes: 9d3ba0b6c0 ("Coresight: Add coresight dummy driver")
Signed-off-by: Jie Gan <quic_jiegan@quicinc.com>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Link: https://lore.kernel.org/r/20240812042844.2890115-1-quic_jiegan@quicinc.com
The .remove() callback for a platform driver returns an int which makes
many driver authors wrongly assume it's possible to do error handling by
returning an error code. However the value returned is ignored (apart
from emitting a warning) and this typically results in resource leaks.
To improve here there is a quest to make the remove callback return
void. In the first step of this quest all drivers are converted to
.remove_new(), which already returns void. Eventually after all drivers
are converted, .remove_new() will be renamed to .remove().
Trivially convert this driver from always returning zero in the remove
callback to the void returning variant.
Reviewed-by: James Clark <james.clark@arm.com>
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Link: https://lore.kernel.org/r/20231116173301.708873-9-u.kleine-koenig@pengutronix.de
The init/exit() of driver only calls platform_driver_register/unregister,
it can be simpilfied with module_platform_driver.
Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Link: https://lore.kernel.org/r/20230804092709.1359264-1-yangyingliang@huawei.com
Clang's kernel Control Flow Integrity (kCFI) is a compiler-based
security mitigation that ensures the target of an indirect function call
matches the expected type of the call and trapping if they do not match
exactly. The warning -Wincompatible-function-pointer-types-strict aims
to catch these issues at compile time, which reveals:
drivers/hwtracing/coresight/coresight-dummy.c:53:12: error: incompatible function pointer types initializing 'int (*)(struct coresight_device *, struct perf_event *, enum cs_mode)' with an expression of type 'int (struct coresight_device *, struct perf_event *, u32)' (aka 'int (struct coresight_device *, struct perf_event *, unsigned int)') [-Werror,-Wincompatible-function-pointer-types-strict]
53 | .enable = dummy_source_enable,
| ^~~~~~~~~~~~~~~~~~~
drivers/hwtracing/coresight/coresight-dummy.c:62:12: error: incompatible function pointer types initializing 'int (*)(struct coresight_device *, enum cs_mode, void *)' with an expression of type 'int (struct coresight_device *, u32, void *)' (aka 'int (struct coresight_device *, unsigned int, void *)') [-Werror,-Wincompatible-function-pointer-types-strict]
62 | .enable = dummy_sink_enable,
| ^~~~~~~~~~~~~~~~~
2 errors generated.
Commit 9fa3682869 ("coresight: Use enum type for cs_mode wherever
possible") updated the type of the mode parameter in the prototype but
this driver was not introduced until commit 9d3ba0b6c0 ("Coresight:
Add coresight dummy driver") and 'int' is ABI compatible with 'enum
cs_mode', so there is no warning from regular
-Wincompatible-function-pointer-types.
Adjust the type of the mode parameter in the callback implementations in
the coresight dummy driver to match the prototype, clearing up the
warning and avoiding kCFI failures at runtime.
Fixes: 9d3ba0b6c0 ("Coresight: Add coresight dummy driver")
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Link: https://lore.kernel.org/r/20230616-coresight-dummy-fix-kcfi-warnings-v1-1-c55c64f8f0f5@kernel.org
Some Coresight devices that kernel don't have permission to access or
configure. For these devices, a dummy driver is needed to register them as
Coresight devices. The module may also be used to define components that
may not have any programming interfaces, so that paths can be created
in the driver. It provides Coresight API for operations on dummy devices,
such as enabling and disabling them. It also provides the Coresight dummy
sink/source paths for debugging.
Signed-off-by: Hao Zhang <quic_hazha@quicinc.com>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Link: https://lore.kernel.org/r/20230602084149.40031-2-quic_hazha@quicinc.com
