From: Thomas Gleixner Date: Fri, 22 Nov 2024 20:28:49 +0000 (+0100) Subject: tracing: Record task flag NEED_RESCHED_LAZY. X-Git-Tag: v6.13-rc1~39^2~6 X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=0172afefbfbdd8987787c926b40b68400bd1c3d1;p=thirdparty%2Fkernel%2Flinux.git tracing: Record task flag NEED_RESCHED_LAZY. The scheduler added NEED_RESCHED_LAZY scheduling. Record this state as part of trace flags and expose it in the need_resched field. Record and expose NEED_RESCHED_LAZY. [bigeasy: Commit description, documentation bits.] Cc: Peter Zijlstra Cc: Masami Hiramatsu Cc: Mathieu Desnoyers Link: https://lore.kernel.org/20241122202849.7DfYpJR0@linutronix.de Reviewed-by: Ankur Arora Reviewed-by: Steven Rostedt (Google) Signed-off-by: Thomas Gleixner Signed-off-by: Sebastian Andrzej Siewior Signed-off-by: Steven Rostedt (Google) --- diff --git a/Documentation/trace/ftrace.rst b/Documentation/trace/ftrace.rst index 74d5bd801b1a8..272464bb7c602 100644 --- a/Documentation/trace/ftrace.rst +++ b/Documentation/trace/ftrace.rst @@ -1033,9 +1033,13 @@ explains which is which. irqs-off: 'd' interrupts are disabled. '.' otherwise. need-resched: + - 'B' all, TIF_NEED_RESCHED, PREEMPT_NEED_RESCHED and TIF_RESCHED_LAZY is set, - 'N' both TIF_NEED_RESCHED and PREEMPT_NEED_RESCHED is set, - 'n' only TIF_NEED_RESCHED is set, - 'p' only PREEMPT_NEED_RESCHED is set, + - 'L' both PREEMPT_NEED_RESCHED and TIF_RESCHED_LAZY is set, + - 'b' both TIF_NEED_RESCHED and TIF_RESCHED_LAZY is set, + - 'l' only TIF_RESCHED_LAZY is set - '.' otherwise. hardirq/softirq: diff --git a/include/linux/trace_events.h b/include/linux/trace_events.h index 016b29a56c875..2a5df5b62cfc7 100644 --- a/include/linux/trace_events.h +++ b/include/linux/trace_events.h @@ -184,6 +184,7 @@ unsigned int tracing_gen_ctx_irq_test(unsigned int irqs_status); enum trace_flag_type { TRACE_FLAG_IRQS_OFF = 0x01, + TRACE_FLAG_NEED_RESCHED_LAZY = 0x02, TRACE_FLAG_NEED_RESCHED = 0x04, TRACE_FLAG_HARDIRQ = 0x08, TRACE_FLAG_SOFTIRQ = 0x10, diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index 3ef047ed97055..be62f0ea1814d 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -2552,6 +2552,8 @@ unsigned int tracing_gen_ctx_irq_test(unsigned int irqs_status) trace_flags |= TRACE_FLAG_NEED_RESCHED; if (test_preempt_need_resched()) trace_flags |= TRACE_FLAG_PREEMPT_RESCHED; + if (IS_ENABLED(CONFIG_ARCH_HAS_PREEMPT_LAZY) && tif_test_bit(TIF_NEED_RESCHED_LAZY)) + trace_flags |= TRACE_FLAG_NEED_RESCHED_LAZY; return (trace_flags << 16) | (min_t(unsigned int, pc & 0xff, 0xf)) | (min_t(unsigned int, migration_disable_value(), 0xf)) << 4; } diff --git a/kernel/trace/trace_output.c b/kernel/trace/trace_output.c index e08aee34ef63d..da748b7cbc4d5 100644 --- a/kernel/trace/trace_output.c +++ b/kernel/trace/trace_output.c @@ -462,17 +462,29 @@ int trace_print_lat_fmt(struct trace_seq *s, struct trace_entry *entry) bh_off ? 'b' : '.'; - switch (entry->flags & (TRACE_FLAG_NEED_RESCHED | + switch (entry->flags & (TRACE_FLAG_NEED_RESCHED | TRACE_FLAG_NEED_RESCHED_LAZY | TRACE_FLAG_PREEMPT_RESCHED)) { + case TRACE_FLAG_NEED_RESCHED | TRACE_FLAG_NEED_RESCHED_LAZY | TRACE_FLAG_PREEMPT_RESCHED: + need_resched = 'B'; + break; case TRACE_FLAG_NEED_RESCHED | TRACE_FLAG_PREEMPT_RESCHED: need_resched = 'N'; break; + case TRACE_FLAG_NEED_RESCHED_LAZY | TRACE_FLAG_PREEMPT_RESCHED: + need_resched = 'L'; + break; + case TRACE_FLAG_NEED_RESCHED | TRACE_FLAG_NEED_RESCHED_LAZY: + need_resched = 'b'; + break; case TRACE_FLAG_NEED_RESCHED: need_resched = 'n'; break; case TRACE_FLAG_PREEMPT_RESCHED: need_resched = 'p'; break; + case TRACE_FLAG_NEED_RESCHED_LAZY: + need_resched = 'l'; + break; default: need_resched = '.'; break;