srcu: Renaming in preparation for additional reader flavor

Currently, there are only two flavors of readers, normal and NMI-safe.
A number of fields, functions, and types reflect this restriction.
This renaming-only commit prepares for the addition of light-weight
(as in memory-barrier-free) readers.  OK, OK, there is also a drive-by
white-space fixeup!

Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Andrii Nakryiko <andrii@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Kent Overstreet <kent.overstreet@linux.dev>
Cc: <bpf@vger.kernel.org>
Reviewed-by: Neeraj Upadhyay <Neeraj.Upadhyay@amd.com>
Signed-off-by: Frederic Weisbecker <frederic@kernel.org>

diff --git a/include/linux/srcu.h b/include/linux/srcu.h
index 835bbb2d1f88ad7efb4d5db4f4bf8e71fc8e22e9..06728ef6f32a43ea46551fdc7a6c3ba0090f8f23 100644 (file)
--- a/include/linux/srcu.h
+++ b/include/linux/srcu.h
@@ -181,10 +181,9 @@ static inline int srcu_read_lock_held(const struct srcu_struct *ssp)
 #define SRCU_NMI_SAFE          0x2
 
 #if defined(CONFIG_PROVE_RCU) && defined(CONFIG_TREE_SRCU)
-void srcu_check_nmi_safety(struct srcu_struct *ssp, bool nmi_safe);
+void srcu_check_read_flavor(struct srcu_struct *ssp, int read_flavor);
 #else
-static inline void srcu_check_nmi_safety(struct srcu_struct *ssp,
-                                        bool nmi_safe) { }
+static inline void srcu_check_read_flavor(struct srcu_struct *ssp, int read_flavor) { }
 #endif
 
 
@@ -245,7 +244,7 @@ static inline int srcu_read_lock(struct srcu_struct *ssp) __acquires(ssp)
 {
        int retval;
 
-       srcu_check_nmi_safety(ssp, false);
+       srcu_check_read_flavor(ssp, false);
        retval = __srcu_read_lock(ssp);
        srcu_lock_acquire(&ssp->dep_map);
        return retval;
@@ -262,7 +261,7 @@ static inline int srcu_read_lock_nmisafe(struct srcu_struct *ssp) __acquires(ssp
 {
        int retval;
 
-       srcu_check_nmi_safety(ssp, true);
+       srcu_check_read_flavor(ssp, true);
        retval = __srcu_read_lock_nmisafe(ssp);
        rcu_try_lock_acquire(&ssp->dep_map);
        return retval;
@@ -274,7 +273,7 @@ srcu_read_lock_notrace(struct srcu_struct *ssp) __acquires(ssp)
 {
        int retval;
 
-       srcu_check_nmi_safety(ssp, false);
+       srcu_check_read_flavor(ssp, false);
        retval = __srcu_read_lock(ssp);
        return retval;
 }
@@ -303,7 +302,7 @@ srcu_read_lock_notrace(struct srcu_struct *ssp) __acquires(ssp)
 static inline int srcu_down_read(struct srcu_struct *ssp) __acquires(ssp)
 {
        WARN_ON_ONCE(in_nmi());
-       srcu_check_nmi_safety(ssp, false);
+       srcu_check_read_flavor(ssp, false);
        return __srcu_read_lock(ssp);
 }
 
@@ -318,7 +317,7 @@ static inline void srcu_read_unlock(struct srcu_struct *ssp, int idx)
        __releases(ssp)
 {
        WARN_ON_ONCE(idx & ~0x1);
-       srcu_check_nmi_safety(ssp, false);
+       srcu_check_read_flavor(ssp, false);
        srcu_lock_release(&ssp->dep_map);
        __srcu_read_unlock(ssp, idx);
 }
@@ -334,7 +333,7 @@ static inline void srcu_read_unlock_nmisafe(struct srcu_struct *ssp, int idx)
        __releases(ssp)
 {
        WARN_ON_ONCE(idx & ~0x1);
-       srcu_check_nmi_safety(ssp, true);
+       srcu_check_read_flavor(ssp, true);
        rcu_lock_release(&ssp->dep_map);
        __srcu_read_unlock_nmisafe(ssp, idx);
 }
@@ -343,7 +342,7 @@ static inline void srcu_read_unlock_nmisafe(struct srcu_struct *ssp, int idx)
 static inline notrace void
 srcu_read_unlock_notrace(struct srcu_struct *ssp, int idx) __releases(ssp)
 {
-       srcu_check_nmi_safety(ssp, false);
+       srcu_check_read_flavor(ssp, false);
        __srcu_read_unlock(ssp, idx);
 }
 
@@ -360,7 +359,7 @@ static inline void srcu_up_read(struct srcu_struct *ssp, int idx)
 {
        WARN_ON_ONCE(idx & ~0x1);
        WARN_ON_ONCE(in_nmi());
-       srcu_check_nmi_safety(ssp, false);
+       srcu_check_read_flavor(ssp, false);
        __srcu_read_unlock(ssp, idx);
 }
 

diff --git a/include/linux/srcutree.h b/include/linux/srcutree.h
index ed57598394de37eedeb0b97774f0f617cd3da242..ab7d8d215b84ba343d763a168d171eb9e2716dac 100644 (file)
--- a/include/linux/srcutree.h
+++ b/include/linux/srcutree.h
@@ -25,7 +25,7 @@ struct srcu_data {
        /* Read-side state. */
        atomic_long_t srcu_lock_count[2];       /* Locks per CPU. */
        atomic_long_t srcu_unlock_count[2];     /* Unlocks per CPU. */
-       int srcu_nmi_safety;                    /* NMI-safe srcu_struct structure? */
+       int srcu_reader_flavor;                 /* Reader flavor for srcu_struct structure? */
 
        /* Update-side state. */
        spinlock_t __private lock ____cacheline_internodealigned_in_smp;

diff --git a/kernel/rcu/srcutree.c b/kernel/rcu/srcutree.c
index 5b1a315f77bc62f6b201c2ef8f9de6d0dcc57d1f..f259dd83427211ee1fd64e7aa75eea6766c5fd13 100644 (file)
--- a/kernel/rcu/srcutree.c
+++ b/kernel/rcu/srcutree.c
@@ -460,7 +460,7 @@ static unsigned long srcu_readers_unlock_idx(struct srcu_struct *ssp, int idx)
 
                sum += atomic_long_read(&cpuc->srcu_unlock_count[idx]);
                if (IS_ENABLED(CONFIG_PROVE_RCU))
-                       mask = mask | READ_ONCE(cpuc->srcu_nmi_safety);
+                       mask = mask | READ_ONCE(cpuc->srcu_reader_flavor);
        }
        WARN_ONCE(IS_ENABLED(CONFIG_PROVE_RCU) && (mask & (mask >> 1)),
                  "Mixed NMI-safe readers for srcu_struct at %ps.\n", ssp);
@@ -699,25 +699,25 @@ EXPORT_SYMBOL_GPL(cleanup_srcu_struct);
 
 #ifdef CONFIG_PROVE_RCU
 /*
- * Check for consistent NMI safety.
+ * Check for consistent reader flavor.
  */
-void srcu_check_nmi_safety(struct srcu_struct *ssp, bool nmi_safe)
+void srcu_check_read_flavor(struct srcu_struct *ssp, int read_flavor)
 {
-       int nmi_safe_mask = 1 << nmi_safe;
-       int old_nmi_safe_mask;
+       int reader_flavor_mask = 1 << read_flavor;
+       int old_reader_flavor_mask;
        struct srcu_data *sdp;
 
        /* NMI-unsafe use in NMI is a bad sign */
-       WARN_ON_ONCE(!nmi_safe && in_nmi());
+       WARN_ON_ONCE(!read_flavor && in_nmi());
        sdp = raw_cpu_ptr(ssp->sda);
-       old_nmi_safe_mask = READ_ONCE(sdp->srcu_nmi_safety);
-       if (!old_nmi_safe_mask) {
-               WRITE_ONCE(sdp->srcu_nmi_safety, nmi_safe_mask);
+       old_reader_flavor_mask = READ_ONCE(sdp->srcu_reader_flavor);
+       if (!old_reader_flavor_mask) {
+               WRITE_ONCE(sdp->srcu_reader_flavor, reader_flavor_mask);
                return;
        }
-       WARN_ONCE(old_nmi_safe_mask != nmi_safe_mask, "CPU %d old state %d new state %d\n", sdp->cpu, old_nmi_safe_mask, nmi_safe_mask);
+       WARN_ONCE(old_reader_flavor_mask != reader_flavor_mask, "CPU %d old state %d new state %d\n", sdp->cpu, old_reader_flavor_mask, reader_flavor_mask);
 }
-EXPORT_SYMBOL_GPL(srcu_check_nmi_safety);
+EXPORT_SYMBOL_GPL(srcu_check_read_flavor);
 #endif /* CONFIG_PROVE_RCU */
 
 /*