diff options
| -rw-r--r-- | include/linux/compiler.h | 2 | ||||
| -rw-r--r-- | kernel/rcu/tree.c | 32 |
2 files changed, 26 insertions, 8 deletions
diff --git a/include/linux/compiler.h b/include/linux/compiler.h index 30827f82ad62..204e76856435 100644 --- a/include/linux/compiler.h +++ b/include/linux/compiler.h @@ -123,7 +123,7 @@ void ftrace_likely_update(struct ftrace_likely_data *f, int val, #ifdef CONFIG_DEBUG_ENTRY /* Begin/end of an instrumentation safe region */ #define instrumentation_begin() ({ \ - asm volatile("%c0:\n\t" \ + asm volatile("%c0: nop\n\t" \ ".pushsection .discard.instr_begin\n\t" \ ".long %c0b - .\n\t" \ ".popsection\n\t" : : "i" (__COUNTER__)); \ diff --git a/kernel/rcu/tree.c b/kernel/rcu/tree.c index c716eadc7617..6c6569e0586c 100644 --- a/kernel/rcu/tree.c +++ b/kernel/rcu/tree.c @@ -250,7 +250,7 @@ static noinstr void rcu_dynticks_eqs_enter(void) * next idle sojourn. */ rcu_dynticks_task_trace_enter(); // Before ->dynticks update! - seq = atomic_add_return(RCU_DYNTICK_CTRL_CTR, &rdp->dynticks); + seq = arch_atomic_add_return(RCU_DYNTICK_CTRL_CTR, &rdp->dynticks); // RCU is no longer watching. Better be in extended quiescent state! WARN_ON_ONCE(IS_ENABLED(CONFIG_RCU_EQS_DEBUG) && (seq & RCU_DYNTICK_CTRL_CTR)); @@ -274,13 +274,13 @@ static noinstr void rcu_dynticks_eqs_exit(void) * and we also must force ordering with the next RCU read-side * critical section. */ - seq = atomic_add_return(RCU_DYNTICK_CTRL_CTR, &rdp->dynticks); + seq = arch_atomic_add_return(RCU_DYNTICK_CTRL_CTR, &rdp->dynticks); // RCU is now watching. Better not be in an extended quiescent state! rcu_dynticks_task_trace_exit(); // After ->dynticks update! WARN_ON_ONCE(IS_ENABLED(CONFIG_RCU_EQS_DEBUG) && !(seq & RCU_DYNTICK_CTRL_CTR)); if (seq & RCU_DYNTICK_CTRL_MASK) { - atomic_andnot(RCU_DYNTICK_CTRL_MASK, &rdp->dynticks); + arch_atomic_andnot(RCU_DYNTICK_CTRL_MASK, &rdp->dynticks); smp_mb__after_atomic(); /* _exit after clearing mask. */ } } @@ -313,7 +313,7 @@ static __always_inline bool rcu_dynticks_curr_cpu_in_eqs(void) { struct rcu_data *rdp = this_cpu_ptr(&rcu_data); - return !(atomic_read(&rdp->dynticks) & RCU_DYNTICK_CTRL_CTR); + return !(arch_atomic_read(&rdp->dynticks) & RCU_DYNTICK_CTRL_CTR); } /* @@ -633,6 +633,10 @@ static noinstr void rcu_eqs_enter(bool user) do_nocb_deferred_wakeup(rdp); rcu_prepare_for_idle(); rcu_preempt_deferred_qs(current); + + // instrumentation for the noinstr rcu_dynticks_eqs_enter() + instrument_atomic_write(&rdp->dynticks, sizeof(rdp->dynticks)); + instrumentation_end(); WRITE_ONCE(rdp->dynticks_nesting, 0); /* Avoid irq-access tearing. */ // RCU is watching here ... @@ -692,6 +696,7 @@ noinstr void rcu_nmi_exit(void) { struct rcu_data *rdp = this_cpu_ptr(&rcu_data); + instrumentation_begin(); /* * Check for ->dynticks_nmi_nesting underflow and bad ->dynticks. * (We are exiting an NMI handler, so RCU better be paying attention @@ -705,7 +710,6 @@ noinstr void rcu_nmi_exit(void) * leave it in non-RCU-idle state. */ if (rdp->dynticks_nmi_nesting != 1) { - instrumentation_begin(); trace_rcu_dyntick(TPS("--="), rdp->dynticks_nmi_nesting, rdp->dynticks_nmi_nesting - 2, atomic_read(&rdp->dynticks)); WRITE_ONCE(rdp->dynticks_nmi_nesting, /* No store tearing. */ @@ -714,13 +718,15 @@ noinstr void rcu_nmi_exit(void) return; } - instrumentation_begin(); /* This NMI interrupted an RCU-idle CPU, restore RCU-idleness. */ trace_rcu_dyntick(TPS("Startirq"), rdp->dynticks_nmi_nesting, 0, atomic_read(&rdp->dynticks)); WRITE_ONCE(rdp->dynticks_nmi_nesting, 0); /* Avoid store tearing. */ if (!in_nmi()) rcu_prepare_for_idle(); + + // instrumentation for the noinstr rcu_dynticks_eqs_enter() + instrument_atomic_write(&rdp->dynticks, sizeof(rdp->dynticks)); instrumentation_end(); // RCU is watching here ... @@ -838,6 +844,10 @@ static void noinstr rcu_eqs_exit(bool user) rcu_dynticks_eqs_exit(); // ... but is watching here. instrumentation_begin(); + + // instrumentation for the noinstr rcu_dynticks_eqs_exit() + instrument_atomic_write(&rdp->dynticks, sizeof(rdp->dynticks)); + rcu_cleanup_after_idle(); trace_rcu_dyntick(TPS("End"), rdp->dynticks_nesting, 1, atomic_read(&rdp->dynticks)); WARN_ON_ONCE(IS_ENABLED(CONFIG_RCU_EQS_DEBUG) && !user && !is_idle_task(current)); @@ -983,13 +993,21 @@ noinstr void rcu_nmi_enter(void) if (!in_nmi()) rcu_cleanup_after_idle(); + instrumentation_begin(); + // instrumentation for the noinstr rcu_dynticks_curr_cpu_in_eqs() + instrument_atomic_read(&rdp->dynticks, sizeof(rdp->dynticks)); + // instrumentation for the noinstr rcu_dynticks_eqs_exit() + instrument_atomic_write(&rdp->dynticks, sizeof(rdp->dynticks)); + incby = 1; } else if (!in_nmi()) { instrumentation_begin(); rcu_irq_enter_check_tick(); instrumentation_end(); + } else { + instrumentation_begin(); } - instrumentation_begin(); + trace_rcu_dyntick(incby == 1 ? TPS("Endirq") : TPS("++="), rdp->dynticks_nmi_nesting, rdp->dynticks_nmi_nesting + incby, atomic_read(&rdp->dynticks)); |