diff options
Diffstat (limited to 'Documentation/dev-tools')
| -rw-r--r-- | Documentation/dev-tools/kcov.rst | 17 | ||||
| -rw-r--r-- | Documentation/dev-tools/kgdb.rst | 24 | ||||
| -rw-r--r-- | Documentation/dev-tools/kselftest.rst | 3 |
3 files changed, 35 insertions, 9 deletions
diff --git a/Documentation/dev-tools/kcov.rst b/Documentation/dev-tools/kcov.rst index 1c4e1825d769..8548b0b04e43 100644 --- a/Documentation/dev-tools/kcov.rst +++ b/Documentation/dev-tools/kcov.rst @@ -217,14 +217,15 @@ This allows to collect coverage from two types of kernel background threads: the global ones, that are spawned during kernel boot in a limited number of instances (e.g. one USB hub_event() worker thread is spawned per USB HCD); and the local ones, that are spawned when a user interacts with -some kernel interface (e.g. vhost workers). +some kernel interface (e.g. vhost workers); as well as from soft +interrupts. -To enable collecting coverage from a global background thread, a unique -global handle must be assigned and passed to the corresponding -kcov_remote_start() call. Then a userspace process can pass a list of such -handles to the KCOV_REMOTE_ENABLE ioctl in the handles array field of the -kcov_remote_arg struct. This will attach the used kcov device to the code -sections, that are referenced by those handles. +To enable collecting coverage from a global background thread or from a +softirq, a unique global handle must be assigned and passed to the +corresponding kcov_remote_start() call. Then a userspace process can pass +a list of such handles to the KCOV_REMOTE_ENABLE ioctl in the handles +array field of the kcov_remote_arg struct. This will attach the used kcov +device to the code sections, that are referenced by those handles. Since there might be many local background threads spawned from different userspace processes, we can't use a single global handle per annotation. @@ -242,7 +243,7 @@ handles as they don't belong to a particular subsystem. The bytes 4-7 are currently reserved and must be zero. In the future the number of bytes used for the subsystem or handle ids might be increased. -When a particular userspace proccess collects coverage by via a common +When a particular userspace proccess collects coverage via a common handle, kcov will collect coverage for each code section that is annotated to use the common handle obtained as kcov_handle from the current task_struct. However non common handles allow to collect coverage diff --git a/Documentation/dev-tools/kgdb.rst b/Documentation/dev-tools/kgdb.rst index d38be58f872a..61293f40bc6e 100644 --- a/Documentation/dev-tools/kgdb.rst +++ b/Documentation/dev-tools/kgdb.rst @@ -274,6 +274,30 @@ don't like this are to hack gdb to send the :kbd:`SysRq-G` for you as well as on the initial connect, or to use a debugger proxy that allows an unmodified gdb to do the debugging. +Kernel parameter: ``kgdboc_earlycon`` +------------------------------------- + +If you specify the kernel parameter ``kgdboc_earlycon`` and your serial +driver registers a boot console that supports polling (doesn't need +interrupts and implements a nonblocking read() function) kgdb will attempt +to work using the boot console until it can transition to the regular +tty driver specified by the ``kgdboc`` parameter. + +Normally there is only one boot console (especially that implements the +read() function) so just adding ``kgdboc_earlycon`` on its own is +sufficient to make this work. If you have more than one boot console you +can add the boot console's name to differentiate. Note that names that +are registered through the boot console layer and the tty layer are not +the same for the same port. + +For instance, on one board to be explicit you might do:: + + kgdboc_earlycon=qcom_geni kgdboc=ttyMSM0 + +If the only boot console on the device was "qcom_geni", you could simplify:: + + kgdboc_earlycon kgdboc=ttyMSM0 + Kernel parameter: ``kgdbwait`` ------------------------------ diff --git a/Documentation/dev-tools/kselftest.rst b/Documentation/dev-tools/kselftest.rst index 61ae13c44f91..5d1f56fcd2e7 100644 --- a/Documentation/dev-tools/kselftest.rst +++ b/Documentation/dev-tools/kselftest.rst @@ -301,7 +301,8 @@ Helpers .. kernel-doc:: tools/testing/selftests/kselftest_harness.h :functions: TH_LOG TEST TEST_SIGNAL FIXTURE FIXTURE_DATA FIXTURE_SETUP - FIXTURE_TEARDOWN TEST_F TEST_HARNESS_MAIN + FIXTURE_TEARDOWN TEST_F TEST_HARNESS_MAIN FIXTURE_VARIANT + FIXTURE_VARIANT_ADD Operators --------- |