Re: [PATCH v3 16/51] cpuidle: Annotate poll_idle()
From: Peter Zijlstra <peterz@infradead.org>
Date: 2023-01-20 09:57:56
Also in:
linux-acpi, linux-arch, linux-arm-msm, linux-clk, linux-m68k, linux-mips, linux-mm, linux-omap, linux-perf-users, linux-pm, linux-riscv, linux-s390, linux-samsung-soc, linux-sh, linux-tegra, linux-trace-kernel, linux-um, lkml, loongarch, sparclinux, virtualization
Subsystem:
cpu idle time management framework, scheduler, the rest, x86 architecture (32-bit and 64-bit) · Maintainers:
"Rafael J. Wysocki", Daniel Lezcano, Ingo Molnar, Peter Zijlstra, Juri Lelli, Vincent Guittot, Linus Torvalds, Thomas Gleixner, Borislav Petkov, Dave Hansen
On Thu, Jan 12, 2023 at 08:43:30PM +0100, Peter Zijlstra wrote:
quoted hunk ↗ jump to hunk
The __cpuidle functions will become a noinstr class, as such they need explicit annotations. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Rafael J. Wysocki <redacted> Acked-by: Frederic Weisbecker <frederic@kernel.org> Tested-by: Tony Lindgren <tony@atomide.com> Tested-by: Ulf Hansson <redacted> --- drivers/cpuidle/poll_state.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-)--- a/drivers/cpuidle/poll_state.c +++ b/drivers/cpuidle/poll_state.c@@ -13,7 +13,10 @@ static int __cpuidle poll_idle(struct cpuidle_device *dev, struct cpuidle_driver *drv, int index) { - u64 time_start = local_clock(); + u64 time_start; + + instrumentation_begin(); + time_start = local_clock(); dev->poll_time_limit = false;@@ -39,6 +42,7 @@ static int __cpuidle poll_idle(struct cp raw_local_irq_disable(); current_clr_polling(); + instrumentation_end(); return index; }
Pff, this patch is garbage. However wrote it didn't have his brain engaged :/ Something like the below fixes it, but I still need to build me funny configs like ia64 and paravirt to see if I didn't wreck me something...
diff --git a/arch/x86/kernel/tsc.c b/arch/x86/kernel/tsc.c
index a78e73da4a74..70c07e11caa6 100644
--- a/arch/x86/kernel/tsc.c
+++ b/arch/x86/kernel/tsc.c@@ -215,7 +215,7 @@ static void __init cyc2ns_init_secondary_cpus(void) /* * Scheduler clock - returns current time in nanosec units. */ -u64 native_sched_clock(void) +noinstr u64 native_sched_clock(void) { if (static_branch_likely(&__use_tsc)) { u64 tsc_now = rdtsc();
diff --git a/drivers/cpuidle/cpuidle.c b/drivers/cpuidle/cpuidle.c
index 500d1720421e..0b00f21cefe3 100644
--- a/drivers/cpuidle/cpuidle.c
+++ b/drivers/cpuidle/cpuidle.c@@ -426,7 +426,7 @@ void cpuidle_reflect(struct cpuidle_device *dev, int index) * @dev: the cpuidle device * */ -u64 cpuidle_poll_time(struct cpuidle_driver *drv, +__cpuidle u64 cpuidle_poll_time(struct cpuidle_driver *drv, struct cpuidle_device *dev) { int i;
diff --git a/drivers/cpuidle/poll_state.c b/drivers/cpuidle/poll_state.c
index d25ec52846e6..bdcfeaecd228 100644
--- a/drivers/cpuidle/poll_state.c
+++ b/drivers/cpuidle/poll_state.c@@ -15,7 +15,6 @@ static int __cpuidle poll_idle(struct cpuidle_device *dev, { u64 time_start; - instrumentation_begin(); time_start = local_clock(); dev->poll_time_limit = false;
@@ -42,7 +41,6 @@ static int __cpuidle poll_idle(struct cpuidle_device *dev, raw_local_irq_disable(); current_clr_polling(); - instrumentation_end(); return index; }
diff --git a/include/linux/sched/clock.h b/include/linux/sched/clock.h
index 867d588314e0..7960f0769884 100644
--- a/include/linux/sched/clock.h
+++ b/include/linux/sched/clock.h@@ -45,7 +45,7 @@ static inline u64 cpu_clock(int cpu) return sched_clock(); } -static inline u64 local_clock(void) +static __always_inline u64 local_clock(void) { return sched_clock(); }
@@ -79,7 +79,7 @@ static inline u64 cpu_clock(int cpu) return sched_clock_cpu(cpu); } -static inline u64 local_clock(void) +static __always_inline u64 local_clock(void) { return sched_clock_cpu(raw_smp_processor_id()); }
diff --git a/kernel/sched/clock.c b/kernel/sched/clock.c
index e374c0c923da..6b3b0559e53c 100644
--- a/kernel/sched/clock.c
+++ b/kernel/sched/clock.c@@ -260,7 +260,7 @@ notrace static inline u64 wrap_max(u64 x, u64 y) * - filter out backward motion * - use the GTOD tick value to create a window to filter crazy TSC values */ -notrace static u64 sched_clock_local(struct sched_clock_data *scd) +noinstr static u64 sched_clock_local(struct sched_clock_data *scd) { u64 now, clock, old_clock, min_clock, max_clock, gtod; s64 delta;
@@ -287,7 +287,7 @@ notrace static u64 sched_clock_local(struct sched_clock_data *scd) clock = wrap_max(clock, min_clock); clock = wrap_min(clock, max_clock); - if (!try_cmpxchg64(&scd->clock, &old_clock, clock)) + if (!arch_try_cmpxchg64(&scd->clock, &old_clock, clock)) goto again; return clock;
@@ -360,7 +360,7 @@ notrace static u64 sched_clock_remote(struct sched_clock_data *scd) * * See cpu_clock(). */ -notrace u64 sched_clock_cpu(int cpu) +noinstr u64 sched_clock_cpu(int cpu) { struct sched_clock_data *scd; u64 clock;