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seqlock: Prefix internal seqcount_t-only macros with a "do_"
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When the seqcount_LOCKNAME_t group of data types were introduced, two
classes of seqlock.h sequence counter macros were added:

  - An external public API which can either take a plain seqcount_t or
    any of the seqcount_LOCKNAME_t variants.

  - An internal API which takes only a plain seqcount_t.

To distinguish between the two groups, the "*_seqcount_t_*" pattern was
used for the latter. This confused a number of mm/ call-site developers,
and Linus also commented that it was not a standard practice for marking
seqlock.h internal APIs.

Distinguish the latter group of macros by prefixing a "do_".

Signed-off-by: Ahmed S. Darwish <[email protected]>
Signed-off-by: Peter Zijlstra (Intel) <[email protected]>
Link: https://lkml.kernel.org/r/CAHk-=wikhGExmprXgaW+MVXG1zsGpztBbVwOb23vetk41EtTBQ@mail.gmail.com
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@a-darwish
a-darwish authored and Peter Zijlstra committed Dec 9, 2020
1 parent cf48647 commit 66bcfcd
Showing 1 changed file with 33 additions and 33 deletions.
66 changes: 33 additions & 33 deletions include/linux/seqlock.h
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Original file line number Diff line number Diff line change
Expand Up @@ -425,9 +425,9 @@ SEQCOUNT_LOCKNAME(ww_mutex, struct ww_mutex, true, &s->lock->base, ww_mu
* Return: true if a read section retry is required, else false
*/
#define __read_seqcount_retry(s, start) \
__read_seqcount_t_retry(seqprop_ptr(s), start)
do___read_seqcount_retry(seqprop_ptr(s), start)

static inline int __read_seqcount_t_retry(const seqcount_t *s, unsigned start)
static inline int do___read_seqcount_retry(const seqcount_t *s, unsigned start)
{
kcsan_atomic_next(0);
return unlikely(READ_ONCE(s->sequence) != start);
Expand All @@ -445,12 +445,12 @@ static inline int __read_seqcount_t_retry(const seqcount_t *s, unsigned start)
* Return: true if a read section retry is required, else false
*/
#define read_seqcount_retry(s, start) \
read_seqcount_t_retry(seqprop_ptr(s), start)
do_read_seqcount_retry(seqprop_ptr(s), start)

static inline int read_seqcount_t_retry(const seqcount_t *s, unsigned start)
static inline int do_read_seqcount_retry(const seqcount_t *s, unsigned start)
{
smp_rmb();
return __read_seqcount_t_retry(s, start);
return do___read_seqcount_retry(s, start);
}

/**
Expand All @@ -462,10 +462,10 @@ do { \
if (seqprop_preemptible(s)) \
preempt_disable(); \
\
raw_write_seqcount_t_begin(seqprop_ptr(s)); \
do_raw_write_seqcount_begin(seqprop_ptr(s)); \
} while (0)

static inline void raw_write_seqcount_t_begin(seqcount_t *s)
static inline void do_raw_write_seqcount_begin(seqcount_t *s)
{
kcsan_nestable_atomic_begin();
s->sequence++;
Expand All @@ -478,13 +478,13 @@ static inline void raw_write_seqcount_t_begin(seqcount_t *s)
*/
#define raw_write_seqcount_end(s) \
do { \
raw_write_seqcount_t_end(seqprop_ptr(s)); \
do_raw_write_seqcount_end(seqprop_ptr(s)); \
\
if (seqprop_preemptible(s)) \
preempt_enable(); \
} while (0)

static inline void raw_write_seqcount_t_end(seqcount_t *s)
static inline void do_raw_write_seqcount_end(seqcount_t *s)
{
smp_wmb();
s->sequence++;
Expand All @@ -506,12 +506,12 @@ do { \
if (seqprop_preemptible(s)) \
preempt_disable(); \
\
write_seqcount_t_begin_nested(seqprop_ptr(s), subclass); \
do_write_seqcount_begin_nested(seqprop_ptr(s), subclass); \
} while (0)

static inline void write_seqcount_t_begin_nested(seqcount_t *s, int subclass)
static inline void do_write_seqcount_begin_nested(seqcount_t *s, int subclass)
{
raw_write_seqcount_t_begin(s);
do_raw_write_seqcount_begin(s);
seqcount_acquire(&s->dep_map, subclass, 0, _RET_IP_);
}

Expand All @@ -533,12 +533,12 @@ do { \
if (seqprop_preemptible(s)) \
preempt_disable(); \
\
write_seqcount_t_begin(seqprop_ptr(s)); \
do_write_seqcount_begin(seqprop_ptr(s)); \
} while (0)

static inline void write_seqcount_t_begin(seqcount_t *s)
static inline void do_write_seqcount_begin(seqcount_t *s)
{
write_seqcount_t_begin_nested(s, 0);
do_write_seqcount_begin_nested(s, 0);
}

/**
Expand All @@ -549,16 +549,16 @@ static inline void write_seqcount_t_begin(seqcount_t *s)
*/
#define write_seqcount_end(s) \
do { \
write_seqcount_t_end(seqprop_ptr(s)); \
do_write_seqcount_end(seqprop_ptr(s)); \
\
if (seqprop_preemptible(s)) \
preempt_enable(); \
} while (0)

static inline void write_seqcount_t_end(seqcount_t *s)
static inline void do_write_seqcount_end(seqcount_t *s)
{
seqcount_release(&s->dep_map, _RET_IP_);
raw_write_seqcount_t_end(s);
do_raw_write_seqcount_end(s);
}

/**
Expand Down Expand Up @@ -603,9 +603,9 @@ static inline void write_seqcount_t_end(seqcount_t *s)
* }
*/
#define raw_write_seqcount_barrier(s) \
raw_write_seqcount_t_barrier(seqprop_ptr(s))
do_raw_write_seqcount_barrier(seqprop_ptr(s))

static inline void raw_write_seqcount_t_barrier(seqcount_t *s)
static inline void do_raw_write_seqcount_barrier(seqcount_t *s)
{
kcsan_nestable_atomic_begin();
s->sequence++;
Expand All @@ -623,9 +623,9 @@ static inline void raw_write_seqcount_t_barrier(seqcount_t *s)
* will complete successfully and see data older than this.
*/
#define write_seqcount_invalidate(s) \
write_seqcount_t_invalidate(seqprop_ptr(s))
do_write_seqcount_invalidate(seqprop_ptr(s))

static inline void write_seqcount_t_invalidate(seqcount_t *s)
static inline void do_write_seqcount_invalidate(seqcount_t *s)
{
smp_wmb();
kcsan_nestable_atomic_begin();
Expand Down Expand Up @@ -865,9 +865,9 @@ static inline unsigned read_seqretry(const seqlock_t *sl, unsigned start)
}

/*
* For all seqlock_t write side functions, use write_seqcount_*t*_begin()
* instead of the generic write_seqcount_begin(). This way, no redundant
* lockdep_assert_held() checks are added.
* For all seqlock_t write side functions, use the the internal
* do_write_seqcount_begin() instead of generic write_seqcount_begin().
* This way, no redundant lockdep_assert_held() checks are added.
*/

/**
Expand All @@ -886,7 +886,7 @@ static inline unsigned read_seqretry(const seqlock_t *sl, unsigned start)
static inline void write_seqlock(seqlock_t *sl)
{
spin_lock(&sl->lock);
write_seqcount_t_begin(&sl->seqcount.seqcount);
do_write_seqcount_begin(&sl->seqcount.seqcount);
}

/**
Expand All @@ -898,7 +898,7 @@ static inline void write_seqlock(seqlock_t *sl)
*/
static inline void write_sequnlock(seqlock_t *sl)
{
write_seqcount_t_end(&sl->seqcount.seqcount);
do_write_seqcount_end(&sl->seqcount.seqcount);
spin_unlock(&sl->lock);
}

Expand All @@ -912,7 +912,7 @@ static inline void write_sequnlock(seqlock_t *sl)
static inline void write_seqlock_bh(seqlock_t *sl)
{
spin_lock_bh(&sl->lock);
write_seqcount_t_begin(&sl->seqcount.seqcount);
do_write_seqcount_begin(&sl->seqcount.seqcount);
}

/**
Expand All @@ -925,7 +925,7 @@ static inline void write_seqlock_bh(seqlock_t *sl)
*/
static inline void write_sequnlock_bh(seqlock_t *sl)
{
write_seqcount_t_end(&sl->seqcount.seqcount);
do_write_seqcount_end(&sl->seqcount.seqcount);
spin_unlock_bh(&sl->lock);
}

Expand All @@ -939,7 +939,7 @@ static inline void write_sequnlock_bh(seqlock_t *sl)
static inline void write_seqlock_irq(seqlock_t *sl)
{
spin_lock_irq(&sl->lock);
write_seqcount_t_begin(&sl->seqcount.seqcount);
do_write_seqcount_begin(&sl->seqcount.seqcount);
}

/**
Expand All @@ -951,7 +951,7 @@ static inline void write_seqlock_irq(seqlock_t *sl)
*/
static inline void write_sequnlock_irq(seqlock_t *sl)
{
write_seqcount_t_end(&sl->seqcount.seqcount);
do_write_seqcount_end(&sl->seqcount.seqcount);
spin_unlock_irq(&sl->lock);
}

Expand All @@ -960,7 +960,7 @@ static inline unsigned long __write_seqlock_irqsave(seqlock_t *sl)
unsigned long flags;

spin_lock_irqsave(&sl->lock, flags);
write_seqcount_t_begin(&sl->seqcount.seqcount);
do_write_seqcount_begin(&sl->seqcount.seqcount);
return flags;
}

Expand Down Expand Up @@ -989,7 +989,7 @@ static inline unsigned long __write_seqlock_irqsave(seqlock_t *sl)
static inline void
write_sequnlock_irqrestore(seqlock_t *sl, unsigned long flags)
{
write_seqcount_t_end(&sl->seqcount.seqcount);
do_write_seqcount_end(&sl->seqcount.seqcount);
spin_unlock_irqrestore(&sl->lock, flags);
}

Expand Down

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