From 9cc63f8bcd560c760d0b12e15bba8f81c86237cf Mon Sep 17 00:00:00 2001 From: "Paul E. McKenney" Date: Fri, 14 Aug 2026 15:43:51 -0700 Subject: Merge branches 'expcb.2026.07.24a', 'misc.2026.07.30a', 'rcu-tasks.2026.07.30a', 'srcu.2026.08.11a' and 'torture.2026.08.14a' into HEAD Changes: Make expedited grace periods expedite normal RCU callbacks Miscellaneous fixes: * Improve diagnostic output with character task states. * Mark accesses to inform KCSAN of concurrency design. * Move from kmalloc() to kmalloc_obj(). * Documentation updates. * Improve handling of RCU deferred quiescent states. * Clean up unused function arguments and structure fields. * Reduce show_rcu_gp_kthreads() stack space. Tasks RCU updates: * Clean up after SRCU re-implementation of Tasks Trace RCU. * Mark accesses to inform KCSAN of concurrency design. * Add ->lazy_timer status to diagnostic output. * Remove an unnecessary memory barrier. * Fix a data race, courtesy of KCSAN. * Documentation updates. * Convert cond_resched_tasks_rcu_qs() from macro to static inline function. SRCU updates: * Add Rust helpers for SRCU. * Avoid losing queued work at cleanup_srcu_struct() time. Torture-test updates: * Preparation work for immediate RCU priority deboosting. * Test RCU readers from real interrupt handlers (as opposed to softirq). * Simplify code through use of cpumask_next_wrap(). * Improve diagnostic output with character task states. * Add rcutorture.nwriters parameter to allow lightweight stall testing, and rcutorture.stall_only to make doing so easier. * Test an RCU Tasks Trace grace period implying an RCU grace period. * Make RCU Tasks Trace torturing track reader batches. * Fix a data race, courtesy of KCSAN. * Plug a shuffle_tmp_mask memory leak on kthread spawn failure. --- tools/perf/util/trace-event.c | 118 ++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 118 insertions(+) create mode 100644 tools/perf/util/trace-event.c (limited to 'tools/perf/util/trace-event.c') diff --git a/tools/perf/util/trace-event.c b/tools/perf/util/trace-event.c new file mode 100644 index 000000000..6a8c66c64 --- /dev/null +++ b/tools/perf/util/trace-event.c @@ -0,0 +1,118 @@ +// SPDX-License-Identifier: GPL-2.0 +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include "trace-event.h" +#include "machine.h" + +/* + * global trace_event object used by trace_event__tp_format + * + * TODO There's no cleanup call for this. Add some sort of + * __exit function support and call trace_event__cleanup + * there. + */ +static struct trace_event tevent; +static bool tevent_initialized; + +int trace_event__init(struct trace_event *t) +{ + struct tep_handle *pevent = tep_alloc(); + + if (pevent) { + t->plugin_list = tep_load_plugins(pevent); + t->pevent = pevent; + } + + return pevent ? 0 : -1; +} + +static int trace_event__init2(void) +{ + int be = tep_is_bigendian(); + struct tep_handle *pevent; + + if (trace_event__init(&tevent)) + return -1; + + pevent = tevent.pevent; + tep_set_flag(pevent, TEP_NSEC_OUTPUT); + tep_set_file_bigendian(pevent, be); + tep_set_local_bigendian(pevent, be); + tevent_initialized = true; + return 0; +} + +int trace_event__register_resolver(struct machine *machine, + tep_func_resolver_t *func) +{ + if (!tevent_initialized && trace_event__init2()) + return -1; + + return tep_set_function_resolver(tevent.pevent, func, machine); +} + +void trace_event__cleanup(struct trace_event *t) +{ + tep_unload_plugins(t->plugin_list, t->pevent); + tep_free(t->pevent); +} + +/* + * Returns pointer with encoded error via interface. + */ +static struct tep_event* +tp_format(const char *sys, const char *name) +{ + char *tp_dir = get_events_file(sys); + struct tep_handle *pevent = tevent.pevent; + struct tep_event *event = NULL; + char path[PATH_MAX]; + size_t size; + char *data; + int err; + + if (!tp_dir) + return ERR_PTR(-errno); + + scnprintf(path, PATH_MAX, "%s/%s/format", tp_dir, name); + put_events_file(tp_dir); + + err = filename__read_str(path, &data, &size); + if (err) + return ERR_PTR(err); + + tep_parse_format(pevent, &event, data, size, sys); + + free(data); + return event; +} + +/* + * Returns pointer with encoded error via interface. + */ +struct tep_event* +trace_event__tp_format(const char *sys, const char *name) +{ + if (!tevent_initialized && trace_event__init2()) + return ERR_PTR(-ENOMEM); + + return tp_format(sys, name); +} + +struct tep_event *trace_event__tp_format_id(int id) +{ + if (!tevent_initialized && trace_event__init2()) + return ERR_PTR(-ENOMEM); + + return tep_find_event(tevent.pevent, id); +} -- cgit v1.3.1