From ccc319dcb450d57b7befe924453d06804d83ba73 Mon Sep 17 00:00:00 2001 From: Daniel Bristot de Oliveira Date: Fri, 29 Jul 2022 11:38:53 +0200 Subject: rv/monitor: Add the wwnr monitor Per task wakeup while not running (wwnr) monitor. This model is broken, the reason is that a task can be running in the processor without being set as RUNNABLE. Think about a task about to sleep: 1: set_current_state(TASK_UNINTERRUPTIBLE); 2: schedule(); And then imagine an IRQ happening in between the lines one and two, waking the task up. BOOM, the wakeup will happen while the task is running. Q: Why do we need this model, so? A: To test the reactors. Link: https://lkml.kernel.org/r/473c0fc39967250fdebcff8b620311c11dccad30.1659052063.git.bristot@kernel.org Cc: Wim Van Sebroeck Cc: Guenter Roeck Cc: Jonathan Corbet Cc: Ingo Molnar Cc: Thomas Gleixner Cc: Peter Zijlstra Cc: Will Deacon Cc: Catalin Marinas Cc: Marco Elver Cc: Dmitry Vyukov Cc: "Paul E. McKenney" Cc: Shuah Khan Cc: Gabriele Paoloni Cc: Juri Lelli Cc: Clark Williams Cc: Tao Zhou Cc: Randy Dunlap Cc: linux-doc@vger.kernel.org Cc: linux-kernel@vger.kernel.org Cc: linux-trace-devel@vger.kernel.org Signed-off-by: Daniel Bristot de Oliveira Signed-off-by: Steven Rostedt (Google) --- kernel/trace/rv/Kconfig | 12 +++++ kernel/trace/rv/Makefile | 1 + kernel/trace/rv/monitors/wwnr/wwnr.c | 87 ++++++++++++++++++++++++++++++++++++ kernel/trace/rv/monitors/wwnr/wwnr.h | 46 +++++++++++++++++++ 4 files changed, 146 insertions(+) create mode 100644 kernel/trace/rv/monitors/wwnr/wwnr.c create mode 100644 kernel/trace/rv/monitors/wwnr/wwnr.h (limited to 'kernel/trace/rv') diff --git a/kernel/trace/rv/Kconfig b/kernel/trace/rv/Kconfig index e50f3346164a..b259d6e8dc7c 100644 --- a/kernel/trace/rv/Kconfig +++ b/kernel/trace/rv/Kconfig @@ -38,6 +38,18 @@ config RV_MON_WIP For further information, see: Documentation/trace/rv/monitor_wip.rst +config RV_MON_WWNR + depends on RV + select DA_MON_EVENTS_ID + bool "wwnr monitor" + help + Enable wwnr (wakeup while not running) sample monitor, this is a + sample monitor that illustrates the usage of per-task monitor. + The model is borken on purpose: it serves to test reactors. + + For further information, see: + Documentation/trace/rv/monitor_wwnr.rst + config RV_REACTORS bool "Runtime verification reactors" default y diff --git a/kernel/trace/rv/Makefile b/kernel/trace/rv/Makefile index b41109d2750a..af0ff9a46418 100644 --- a/kernel/trace/rv/Makefile +++ b/kernel/trace/rv/Makefile @@ -3,3 +3,4 @@ obj-$(CONFIG_RV) += rv.o obj-$(CONFIG_RV_REACTORS) += rv_reactors.o obj-$(CONFIG_RV_MON_WIP) += monitors/wip/wip.o +obj-$(CONFIG_RV_MON_WWNR) += monitors/wwnr/wwnr.o diff --git a/kernel/trace/rv/monitors/wwnr/wwnr.c b/kernel/trace/rv/monitors/wwnr/wwnr.c new file mode 100644 index 000000000000..599225d9cf38 --- /dev/null +++ b/kernel/trace/rv/monitors/wwnr/wwnr.c @@ -0,0 +1,87 @@ +// SPDX-License-Identifier: GPL-2.0 +#include +#include +#include +#include +#include +#include +#include +#include + +#define MODULE_NAME "wwnr" + +#include +#include + +#include "wwnr.h" + +struct rv_monitor rv_wwnr; +DECLARE_DA_MON_PER_TASK(wwnr, unsigned char); + +static void handle_switch(void *data, bool preempt, struct task_struct *p, + struct task_struct *n, unsigned int prev_state) +{ + /* start monitoring only after the first suspension */ + if (prev_state == TASK_INTERRUPTIBLE) + da_handle_start_event_wwnr(p, switch_out_wwnr); + else + da_handle_event_wwnr(p, switch_out_wwnr); + + da_handle_event_wwnr(n, switch_in_wwnr); +} + +static void handle_wakeup(void *data, struct task_struct *p) +{ + da_handle_event_wwnr(p, wakeup_wwnr); +} + +static int enable_wwnr(void) +{ + int retval; + + retval = da_monitor_init_wwnr(); + if (retval) + return retval; + + rv_attach_trace_probe("wwnr", sched_switch, handle_switch); + rv_attach_trace_probe("wwnr", sched_wakeup, handle_wakeup); + + return 0; +} + +static void disable_wwnr(void) +{ + rv_wwnr.enabled = 0; + + rv_detach_trace_probe("wwnr", sched_switch, handle_switch); + rv_detach_trace_probe("wwnr", sched_wakeup, handle_wakeup); + + da_monitor_destroy_wwnr(); +} + +struct rv_monitor rv_wwnr = { + .name = "wwnr", + .description = "wakeup while not running per-task testing model.", + .enable = enable_wwnr, + .disable = disable_wwnr, + .reset = da_monitor_reset_all_wwnr, + .enabled = 0, +}; + +static int register_wwnr(void) +{ + rv_register_monitor(&rv_wwnr); + return 0; +} + +static void unregister_wwnr(void) +{ + rv_unregister_monitor(&rv_wwnr); +} + +module_init(register_wwnr); +module_exit(unregister_wwnr); + +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Daniel Bristot de Oliveira "); +MODULE_DESCRIPTION("wwnr: wakeup while not running monitor"); diff --git a/kernel/trace/rv/monitors/wwnr/wwnr.h b/kernel/trace/rv/monitors/wwnr/wwnr.h new file mode 100644 index 000000000000..d1afe55cdd4c --- /dev/null +++ b/kernel/trace/rv/monitors/wwnr/wwnr.h @@ -0,0 +1,46 @@ +/* + * Automatically generated C representation of wwnr automaton + * For further information about this format, see kernel documentation: + * Documentation/trace/rv/deterministic_automata.rst + */ + +enum states_wwnr { + not_running_wwnr = 0, + running_wwnr, + state_max_wwnr +}; + +#define INVALID_STATE state_max_wwnr + +enum events_wwnr { + switch_in_wwnr = 0, + switch_out_wwnr, + wakeup_wwnr, + event_max_wwnr +}; + +struct automaton_wwnr { + char *state_names[state_max_wwnr]; + char *event_names[event_max_wwnr]; + unsigned char function[state_max_wwnr][event_max_wwnr]; + unsigned char initial_state; + bool final_states[state_max_wwnr]; +}; + +struct automaton_wwnr automaton_wwnr = { + .state_names = { + "not_running", + "running" + }, + .event_names = { + "switch_in", + "switch_out", + "wakeup" + }, + .function = { + { running_wwnr, INVALID_STATE, not_running_wwnr }, + { INVALID_STATE, not_running_wwnr, INVALID_STATE }, + }, + .initial_state = not_running_wwnr, + .final_states = { 1, 0 }, +}; -- cgit v1.2.3