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authorLinus Torvalds2017-11-13 17:25:06 +0100
committerLinus Torvalds2017-11-13 17:25:06 +0100
commit7832681b365f220151d1c33cc1a8891f10ecdb6f (patch)
treeeeabbcd88f1a9b87b61469857c63a2fcb571115b /include/linux/log2.h
parent/proc/module: use the same logic as /proc/kallsyms for address exposure (diff)
parentdocumentation: fb: update list of available compiled-in fonts (diff)
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Merge tag 'docs-4.15' of git://git.lwn.net/linux
Pull documentation updates from Jonathan Corbet: "A relatively calm cycle for the docs tree again. - The old driver statement has been added to the kernel docs. - We have a couple of new helper scripts. find-unused-docs.sh from Sayli Karnic will point out kerneldoc comments that are not actually used in the documentation. Jani Nikula's documentation-file-ref-check finds references to non-existing files. - A new ftrace document from Steve Rostedt. - Vinod Koul converted the dmaengine docs to RST Beyond that, it's mostly simple fixes. This set reaches outside of Documentation/ a bit more than most. In all cases, the changes are to comment docs, mostly from Randy, in places where there didn't seem to be anybody better to take them" * tag 'docs-4.15' of git://git.lwn.net/linux: (52 commits) documentation: fb: update list of available compiled-in fonts MAINTAINERS: update DMAengine documentation location dmaengine: doc: ReSTize pxa_dma doc dmaengine: doc: ReSTize dmatest doc dmaengine: doc: ReSTize client API doc dmaengine: doc: ReSTize provider doc dmaengine: doc: Add ReST style dmaengine document ftrace/docs: Add documentation on how to use ftrace from within the kernel bug-hunting.rst: Fix an example and a typo in a Sphinx tag scripts: Add a script to find unused documentation samples: Convert timers to use timer_setup() documentation: kernel-api: add more info on bitmap functions Documentation: fix selftests related file refs Documentation: fix ref to power basic-pm-debugging Documentation: fix ref to trace stm content Documentation: fix ref to coccinelle content Documentation: fix ref to workqueue content Documentation: fix ref to sphinx/kerneldoc.py Documentation: fix locking rt-mutex doc refs docs: dev-tools: correct Coccinelle version number ...
Diffstat (limited to 'include/linux/log2.h')
-rw-r--r--include/linux/log2.h42
1 files changed, 23 insertions, 19 deletions
diff --git a/include/linux/log2.h b/include/linux/log2.h
index c373295f359f..41a1ae010993 100644
--- a/include/linux/log2.h
+++ b/include/linux/log2.h
@@ -37,19 +37,23 @@ int __ilog2_u64(u64 n)
}
#endif
-/*
- * Determine whether some value is a power of two, where zero is
+/**
+ * is_power_of_2() - check if a value is a power of two
+ * @n: the value to check
+ *
+ * Determine whether some value is a power of two, where zero is
* *not* considered a power of two.
+ * Return: true if @n is a power of 2, otherwise false.
*/
-
static inline __attribute__((const))
bool is_power_of_2(unsigned long n)
{
return (n != 0 && ((n & (n - 1)) == 0));
}
-/*
- * round up to nearest power of two
+/**
+ * __roundup_pow_of_two() - round up to nearest power of two
+ * @n: value to round up
*/
static inline __attribute__((const))
unsigned long __roundup_pow_of_two(unsigned long n)
@@ -57,8 +61,9 @@ unsigned long __roundup_pow_of_two(unsigned long n)
return 1UL << fls_long(n - 1);
}
-/*
- * round down to nearest power of two
+/**
+ * __rounddown_pow_of_two() - round down to nearest power of two
+ * @n: value to round down
*/
static inline __attribute__((const))
unsigned long __rounddown_pow_of_two(unsigned long n)
@@ -67,12 +72,12 @@ unsigned long __rounddown_pow_of_two(unsigned long n)
}
/**
- * ilog2 - log of base 2 of 32-bit or a 64-bit unsigned value
- * @n - parameter
+ * ilog2 - log base 2 of 32-bit or a 64-bit unsigned value
+ * @n: parameter
*
* constant-capable log of base 2 calculation
* - this can be used to initialise global variables from constant data, hence
- * the massive ternary operator construction
+ * the massive ternary operator construction
*
* selects the appropriately-sized optimised version depending on sizeof(n)
*/
@@ -150,7 +155,7 @@ unsigned long __rounddown_pow_of_two(unsigned long n)
/**
* roundup_pow_of_two - round the given value up to nearest power of two
- * @n - parameter
+ * @n: parameter
*
* round the given value up to the nearest power of two
* - the result is undefined when n == 0
@@ -167,7 +172,7 @@ unsigned long __rounddown_pow_of_two(unsigned long n)
/**
* rounddown_pow_of_two - round the given value down to nearest power of two
- * @n - parameter
+ * @n: parameter
*
* round the given value down to the nearest power of two
* - the result is undefined when n == 0
@@ -180,6 +185,12 @@ unsigned long __rounddown_pow_of_two(unsigned long n)
__rounddown_pow_of_two(n) \
)
+static inline __attribute_const__
+int __order_base_2(unsigned long n)
+{
+ return n > 1 ? ilog2(n - 1) + 1 : 0;
+}
+
/**
* order_base_2 - calculate the (rounded up) base 2 order of the argument
* @n: parameter
@@ -193,13 +204,6 @@ unsigned long __rounddown_pow_of_two(unsigned long n)
* ob2(5) = 3
* ... and so on.
*/
-
-static inline __attribute_const__
-int __order_base_2(unsigned long n)
-{
- return n > 1 ? ilog2(n - 1) + 1 : 0;
-}
-
#define order_base_2(n) \
( \
__builtin_constant_p(n) ? ( \