[dpdk-dev,01/10] eal: add API to align variable to previous power of 2

Message ID 20180216213700.3415-2-pbhagavatula@caviumnetworks.com (mailing list archive)
State Superseded, archived
Delegated to: Jerin Jacob
Headers

Checks

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

Commit Message

Pavan Nikhilesh Feb. 16, 2018, 9:36 p.m. UTC
  Add 32b and 64b API's to align the given variable to the previous power
of 2.

Signed-off-by: Pavan Nikhilesh <pbhagavatula@caviumnetworks.com>
---
 lib/librte_eal/common/include/rte_common.h | 36 ++++++++++++++++++++++++++++++
 1 file changed, 36 insertions(+)
  

Comments

Jerin Jacob Feb. 17, 2018, 4:49 a.m. UTC | #1
-----Original Message-----
> Date: Sat, 17 Feb 2018 03:06:51 +0530
> From: Pavan Nikhilesh <pbhagavatula@caviumnetworks.com>
> To: jerin.jacob@caviumnetworks.com, santosh.shukla@caviumnetworks.com,
>  erik.g.carrillo@intel.com
> Cc: dev@dpdk.org, Pavan Nikhilesh <pbhagavatula@caviumnetworks.com>
> Subject: [dpdk-dev] [PATCH 01/10] eal: add API to align variable to
>  previous power of 2
> X-Mailer: git-send-email 2.16.1
> 
> Add 32b and 64b API's to align the given variable to the previous power
> of 2.

I suggest to send common code changes in separate patch series with unit test
case and mention the dependency in cover letter.


> 
> Signed-off-by: Pavan Nikhilesh <pbhagavatula@caviumnetworks.com>
> ---
>  lib/librte_eal/common/include/rte_common.h | 36 ++++++++++++++++++++++++++++++
>  1 file changed, 36 insertions(+)
> 
> diff --git a/lib/librte_eal/common/include/rte_common.h b/lib/librte_eal/common/include/rte_common.h
> index c7803e41c..126914f07 100644
> --- a/lib/librte_eal/common/include/rte_common.h
> +++ b/lib/librte_eal/common/include/rte_common.h
> @@ -259,6 +259,24 @@ rte_align32pow2(uint32_t x)
>  	return x + 1;
>  }
>  
> +/**
> + * Aligns input parameter to the previous power of 2
> + *
> + * @param x
> + *   The integer value to algin
> + *
> + * @return
> + *   Input parameter aligned to the previous power of 2
> + */
> +static inline uint32_t
> +rte_align32lowpow2(uint32_t x)
> +{
> +	x = rte_align32pow2(x);
> +	x--;
> +
> +	return x - (x >> 1);
> +}
> +
>  /**
>   * Aligns 64b input parameter to the next power of 2
>   *
> @@ -282,6 +300,24 @@ rte_align64pow2(uint64_t v)
>  	return v + 1;
>  }
>  
> +/**
> + * Aligns 64b input parameter to the previous power of 2
> + *
> + * @param v
> + *   The 64b value to align
> + *
> + * @return
> + *   Input parameter aligned to the previous power of 2
> + */
> +static inline uint64_t
> +rte_align64lowpow2(uint64_t v)
> +{
> +	v = rte_align64pow2(v);
> +	v--;
> +
> +	return v - (v >> 1);
> +}
> +
>  /*********** Macros for calculating min and max **********/
>  
>  /**
> -- 
> 2.16.1
>
  

Patch

diff --git a/lib/librte_eal/common/include/rte_common.h b/lib/librte_eal/common/include/rte_common.h
index c7803e41c..126914f07 100644
--- a/lib/librte_eal/common/include/rte_common.h
+++ b/lib/librte_eal/common/include/rte_common.h
@@ -259,6 +259,24 @@  rte_align32pow2(uint32_t x)
 	return x + 1;
 }
 
+/**
+ * Aligns input parameter to the previous power of 2
+ *
+ * @param x
+ *   The integer value to algin
+ *
+ * @return
+ *   Input parameter aligned to the previous power of 2
+ */
+static inline uint32_t
+rte_align32lowpow2(uint32_t x)
+{
+	x = rte_align32pow2(x);
+	x--;
+
+	return x - (x >> 1);
+}
+
 /**
  * Aligns 64b input parameter to the next power of 2
  *
@@ -282,6 +300,24 @@  rte_align64pow2(uint64_t v)
 	return v + 1;
 }
 
+/**
+ * Aligns 64b input parameter to the previous power of 2
+ *
+ * @param v
+ *   The 64b value to align
+ *
+ * @return
+ *   Input parameter aligned to the previous power of 2
+ */
+static inline uint64_t
+rte_align64lowpow2(uint64_t v)
+{
+	v = rte_align64pow2(v);
+	v--;
+
+	return v - (v >> 1);
+}
+
 /*********** Macros for calculating min and max **********/
 
 /**