diff mbox

[dpdk-dev] eal/rwlocks: Try read/write and relock write to read locks added.

Message ID 20180521090812.27058-1-asm@asm.pp.ru (mailing list archive)
State Superseded, archived
Delegated to: Thomas Monjalon
Headers

Checks

Context Check Description
ci/checkpatch success coding style OK
ci/Intel-compilation success Compilation OK

Commit Message

Leonid Myravjev May 21, 2018, 9:08 a.m. UTC 
  From: Leonid Myravjev <myravjev@amicon.ru>

Signed-off-by: Leonid Myravjev <myravjev@amicon.ru>
---
 lib/librte_eal/common/include/generic/rte_rwlock.h | 61 ++++++++++++++++++++++
 1 file changed, 61 insertions(+)

Comments

Thomas Monjalon July 12, 2018, 1:55 p.m. UTC | #1 
Hi,

Unfortunately, after 2 months, nobody reviewed this patch.

You could motivate some reviews by providing some explanations
or context of use.


21/05/2018 11:08, Leonid Myravjev:
> From: Leonid Myravjev <myravjev@amicon.ru>
> 
> Signed-off-by: Leonid Myravjev <myravjev@amicon.ru>
> ---
>  lib/librte_eal/common/include/generic/rte_rwlock.h | 61 ++++++++++++++++++++++
>  1 file changed, 61 insertions(+)
> 
> diff --git a/lib/librte_eal/common/include/generic/rte_rwlock.h b/lib/librte_eal/common/include/generic/rte_rwlock.h
> index 899e9bc43..11212e2b8 100644
> --- a/lib/librte_eal/common/include/generic/rte_rwlock.h
> +++ b/lib/librte_eal/common/include/generic/rte_rwlock.h
> @@ -76,6 +76,30 @@ rte_rwlock_read_lock(rte_rwlock_t *rwl)
>  }
>  
>  /**
> + * Try take lock a read lock.
> + *
> + * @param rwl
> + *   A pointer to a rwlock structure.
> + * @return
> + *   1 if the lock is successfully taken; 0 otherwise.
> + */
> +static inline int
> +rte_rwlock_read_trylock(rte_rwlock_t *rwl)
> +{
> +	int32_t x;
> +	int success = 0;
> +
> +	x = rwl->cnt;
> +	/* write lock is held */
> +	if (x < 0)
> +		return 0;
> +	success = rte_atomic32_cmpset((volatile uint32_t *)&rwl->cnt, x, x + 1);
> +	if (success == 0)
> +		return 0;
> +	return 1;
> +}
> +
> +/**
>   * Release a read lock.
>   *
>   * @param rwl
> @@ -110,6 +134,29 @@ rte_rwlock_write_lock(rte_rwlock_t *rwl)
>  					      0, -1);
>  	}
>  }
> +/**
> + * Try take a write lock.
> + *
> + * @param rwl
> + *   A pointer to a rwlock structure.
> + * @return
> + *   1 if the lock is successfully taken; 0 otherwise.
> + */
> +static inline int
> +rte_rwlock_write_trylock(rte_rwlock_t *rwl)
> +{
> +	int32_t x;
> +	int success = 0;
> +
> +	x = rwl->cnt;
> +	/* a lock is held */
> +	if (x != 0)
> +		return 0;
> +	success = rte_atomic32_cmpset((volatile uint32_t *)&rwl->cnt, 0, -1);
> +	if (success == 0)
> +		return 0;
> +	return 1;
> +}
>  
>  /**
>   * Release a write lock.
> @@ -124,6 +171,20 @@ rte_rwlock_write_unlock(rte_rwlock_t *rwl)
>  }
>  
>  /**
> + * Relock write lock to read
> + *
> + * @param rwl
> + *   A pointer to a rwlock structure.
> + */
> +static inline void
> +rte_rwlock_write_relock_read(rte_rwlock_t *rwl)
> +{
> +	rte_atomic32_add((rte_atomic32_t *)(intptr_t)&rwl->cnt, 2);
> +}
> +
> +
> +
> +/**
>   * Try to execute critical section in a hardware memory transaction, if it
>   * fails or not available take a read lock
>   *
>
Thomas Monjalon March 24, 2021, 9:53 p.m. UTC | #2 
Closing this proposal.

For reference, an implementation with test has been merged
2 years ago:
https://inbox.dpdk.org/dev/1542130061-3702-1-git-send-email-konstantin.ananyev@intel.com/


12/07/2018 15:55, Thomas Monjalon:
> Hi,
> 
> Unfortunately, after 2 months, nobody reviewed this patch.
> 
> You could motivate some reviews by providing some explanations
> or context of use.
> 
> 
> 21/05/2018 11:08, Leonid Myravjev:
> > From: Leonid Myravjev <myravjev@amicon.ru>
> > 
> > Signed-off-by: Leonid Myravjev <myravjev@amicon.ru>
> > ---
> >  lib/librte_eal/common/include/generic/rte_rwlock.h | 61 ++++++++++++++++++++++
> >  1 file changed, 61 insertions(+)
> > 
> > diff --git a/lib/librte_eal/common/include/generic/rte_rwlock.h b/lib/librte_eal/common/include/generic/rte_rwlock.h
> > index 899e9bc43..11212e2b8 100644
> > --- a/lib/librte_eal/common/include/generic/rte_rwlock.h
> > +++ b/lib/librte_eal/common/include/generic/rte_rwlock.h
> > @@ -76,6 +76,30 @@ rte_rwlock_read_lock(rte_rwlock_t *rwl)
> >  }
> >  
> >  /**
> > + * Try take lock a read lock.
> > + *
> > + * @param rwl
> > + *   A pointer to a rwlock structure.
> > + * @return
> > + *   1 if the lock is successfully taken; 0 otherwise.
> > + */
> > +static inline int
> > +rte_rwlock_read_trylock(rte_rwlock_t *rwl)
> > +{
> > +	int32_t x;
> > +	int success = 0;
> > +
> > +	x = rwl->cnt;
> > +	/* write lock is held */
> > +	if (x < 0)
> > +		return 0;
> > +	success = rte_atomic32_cmpset((volatile uint32_t *)&rwl->cnt, x, x + 1);
> > +	if (success == 0)
> > +		return 0;
> > +	return 1;
> > +}
> > +
> > +/**
> >   * Release a read lock.
> >   *
> >   * @param rwl
> > @@ -110,6 +134,29 @@ rte_rwlock_write_lock(rte_rwlock_t *rwl)
> >  					      0, -1);
> >  	}
> >  }
> > +/**
> > + * Try take a write lock.
> > + *
> > + * @param rwl
> > + *   A pointer to a rwlock structure.
> > + * @return
> > + *   1 if the lock is successfully taken; 0 otherwise.
> > + */
> > +static inline int
> > +rte_rwlock_write_trylock(rte_rwlock_t *rwl)
> > +{
> > +	int32_t x;
> > +	int success = 0;
> > +
> > +	x = rwl->cnt;
> > +	/* a lock is held */
> > +	if (x != 0)
> > +		return 0;
> > +	success = rte_atomic32_cmpset((volatile uint32_t *)&rwl->cnt, 0, -1);
> > +	if (success == 0)
> > +		return 0;
> > +	return 1;
> > +}
> >  
> >  /**
> >   * Release a write lock.
> > @@ -124,6 +171,20 @@ rte_rwlock_write_unlock(rte_rwlock_t *rwl)
> >  }
> >  
> >  /**
> > + * Relock write lock to read
> > + *
> > + * @param rwl
> > + *   A pointer to a rwlock structure.
> > + */
> > +static inline void
> > +rte_rwlock_write_relock_read(rte_rwlock_t *rwl)
> > +{
> > +	rte_atomic32_add((rte_atomic32_t *)(intptr_t)&rwl->cnt, 2);
> > +}
diff mbox

Patch

diff --git a/lib/librte_eal/common/include/generic/rte_rwlock.h b/lib/librte_eal/common/include/generic/rte_rwlock.h
index 899e9bc43..11212e2b8 100644
--- a/lib/librte_eal/common/include/generic/rte_rwlock.h
+++ b/lib/librte_eal/common/include/generic/rte_rwlock.h
@@ -76,6 +76,30 @@  rte_rwlock_read_lock(rte_rwlock_t *rwl)
 }
 
 /**
+ * Try take lock a read lock.
+ *
+ * @param rwl
+ *   A pointer to a rwlock structure.
+ * @return
+ *   1 if the lock is successfully taken; 0 otherwise.
+ */
+static inline int
+rte_rwlock_read_trylock(rte_rwlock_t *rwl)
+{
+	int32_t x;
+	int success = 0;
+
+	x = rwl->cnt;
+	/* write lock is held */
+	if (x < 0)
+		return 0;
+	success = rte_atomic32_cmpset((volatile uint32_t *)&rwl->cnt, x, x + 1);
+	if (success == 0)
+		return 0;
+	return 1;
+}
+
+/**
  * Release a read lock.
  *
  * @param rwl
@@ -110,6 +134,29 @@  rte_rwlock_write_lock(rte_rwlock_t *rwl)
 					      0, -1);
 	}
 }
+/**
+ * Try take a write lock.
+ *
+ * @param rwl
+ *   A pointer to a rwlock structure.
+ * @return
+ *   1 if the lock is successfully taken; 0 otherwise.
+ */
+static inline int
+rte_rwlock_write_trylock(rte_rwlock_t *rwl)
+{
+	int32_t x;
+	int success = 0;
+
+	x = rwl->cnt;
+	/* a lock is held */
+	if (x != 0)
+		return 0;
+	success = rte_atomic32_cmpset((volatile uint32_t *)&rwl->cnt, 0, -1);
+	if (success == 0)
+		return 0;
+	return 1;
+}
 
 /**
  * Release a write lock.
@@ -124,6 +171,20 @@  rte_rwlock_write_unlock(rte_rwlock_t *rwl)
 }
 
 /**
+ * Relock write lock to read
+ *
+ * @param rwl
+ *   A pointer to a rwlock structure.
+ */
+static inline void
+rte_rwlock_write_relock_read(rte_rwlock_t *rwl)
+{
+	rte_atomic32_add((rte_atomic32_t *)(intptr_t)&rwl->cnt, 2);
+}
+
+
+
+/**
  * Try to execute critical section in a hardware memory transaction, if it
  * fails or not available take a read lock
  *