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context_tracking: Convert state to atomic_t

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Context tracking's state and dynticks counter are going to be merged
in a single field so that both updates can happen atomically and at the
same time. Prepare for that with converting the state into an atomic_t.

[ paulmck: Apply kernel test robot feedback. ]

Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Neeraj Upadhyay <quic_neeraju@quicinc.com>
Cc: Uladzislau Rezki <uladzislau.rezki@sony.com>
Cc: Joel Fernandes <joel@joelfernandes.org>
Cc: Boqun Feng <boqun.feng@gmail.com>
Cc: Nicolas Saenz Julienne <nsaenz@kernel.org>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Xiongfeng Wang <wangxiongfeng2@huawei.com>
Cc: Yu Liao <liaoyu15@huawei.com>
Cc: Phil Auld <pauld@redhat.com>
Cc: Paul Gortmaker<paul.gortmaker@windriver.com>
Cc: Alex Belits <abelits@marvell.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Reviewed-by: Nicolas Saenz Julienne <nsaenzju@redhat.com>
Tested-by: Nicolas Saenz Julienne <nsaenzju@redhat.com>
This commit is contained in:
Frederic Weisbecker
2022-06-08 16:40:35 +02:00
committed by Paul E. McKenney
parent c33ef43a35
commit 171476775d
5 changed files with 159 additions and 92 deletions
Download Patch File Download Diff File Expand all files Collapse all files
include/linux/context_tracking.h
+10 -22
View File
@@ -56,7 +56,7 @@ static inline enum ctx_state exception_enter(void)
!context_tracking_enabled())
return 0;
prev_ctx = this_cpu_read(context_tracking.state);
prev_ctx = __ct_state();
if (prev_ctx != CONTEXT_KERNEL)
ct_user_exit(prev_ctx);
@@ -86,33 +86,21 @@ static __always_inline void context_tracking_guest_exit(void)
__ct_user_exit(CONTEXT_GUEST);
}
/**
* ct_state() - return the current context tracking state if known
*
* Returns the current cpu's context tracking state if context tracking
* is enabled. If context tracking is disabled, returns
* CONTEXT_DISABLED. This should be used primarily for debugging.
*/
static __always_inline enum ctx_state ct_state(void)
{
return context_tracking_enabled() ?
this_cpu_read(context_tracking.state) : CONTEXT_DISABLED;
}
#define CT_WARN_ON(cond) WARN_ON(context_tracking_enabled() && (cond))
#else
static inline void user_enter(void) { }
static inline void user_exit(void) { }
static inline void user_enter_irqoff(void) { }
static inline void user_exit_irqoff(void) { }
static inline enum ctx_state exception_enter(void) { return 0; }
static inline int exception_enter(void) { return 0; }
static inline void exception_exit(enum ctx_state prev_ctx) { }
static inline enum ctx_state ct_state(void) { return CONTEXT_DISABLED; }
static inline int ct_state(void) { return -1; }
static __always_inline bool context_tracking_guest_enter(void) { return false; }
static inline void context_tracking_guest_exit(void) { }
#define CT_WARN_ON(cond) do { } while (0)
#endif /* !CONFIG_CONTEXT_TRACKING_USER */
#define CT_WARN_ON(cond) WARN_ON(context_tracking_enabled() && (cond))
#ifdef CONFIG_CONTEXT_TRACKING_USER_FORCE
extern void context_tracking_init(void);
#else
@@ -130,16 +118,16 @@ extern void ct_idle_exit(void);
*/
static __always_inline bool rcu_dynticks_curr_cpu_in_eqs(void)
{
return !(arch_atomic_read(this_cpu_ptr(&context_tracking.dynticks)) & 0x1);
return !(arch_atomic_read(this_cpu_ptr(&context_tracking.state)) & RCU_DYNTICKS_IDX);
}
/*
* Increment the current CPU's context_tracking structure's ->dynticks field
* Increment the current CPU's context_tracking structure's ->state field
* with ordering. Return the new value.
*/
static __always_inline unsigned long rcu_dynticks_inc(int incby)
static __always_inline unsigned long ct_state_inc(int incby)
{
return arch_atomic_add_return(incby, this_cpu_ptr(&context_tracking.dynticks));
return arch_atomic_add_return(incby, this_cpu_ptr(&context_tracking.state));
}
#else