diff options
| author | Ingo Molnar <mingo@kernel.org> | 2012-04-13 09:50:21 +0200 |
|---|---|---|
| committer | Ingo Molnar <mingo@kernel.org> | 2012-04-13 09:50:21 +0200 |
| commit | 659c36fcda403013a01b85da07cf2d9711e6d6c7 (patch) | |
| tree | ece2e7d0e2c19ea5a3d0ec172ad0b81a8a19021d /include/asm-generic/getorder.h | |
| parent | 9521d830b6341d1887dcfc2aebde23fbfa5f1473 (diff) | |
| parent | 5a7ed29c7572d00a75e8c4529e30c5ac2ef82271 (diff) | |
Merge tag 'perf-core-for-mingo' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux into perf/core
Fixes and improvements for perf/core:
. Overhaul the tools/ makefiles, gluing them to the top level Makefile, from
Borislav Petkov.
. Move the UI files from tools/perf/util/ui/ to tools/perf/ui/. Also move
the GTK+ browser to tools/perf/ui/gtk/, from Namhyung Kim.
. Only fallback to sw cycles counter on ENOENT for the hw cycles, from
Robert Richter
. Trivial fixes from Robert Richter
. Handle the autogenerated bison/flex files better, from Namhyung and Jiri Olsa.
. Navigate jump instructions in the annotate browser, just press enter or ->,
still needs support for a jump navigation history, i.e. to go back.
. Search string in the annotate browser: same keys as vim:
/ forward
n next backward/forward
? backward
. Clarify number of events/samples in the report header, from Ashay Rane
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'include/asm-generic/getorder.h')
| -rw-r--r-- | include/asm-generic/getorder.h | 53 |
1 files changed, 45 insertions, 8 deletions
diff --git a/include/asm-generic/getorder.h b/include/asm-generic/getorder.h index 67e7245dc9b..65e4468ac53 100644 --- a/include/asm-generic/getorder.h +++ b/include/asm-generic/getorder.h @@ -4,21 +4,58 @@ #ifndef __ASSEMBLY__ #include <linux/compiler.h> +#include <linux/log2.h> -/* Pure 2^n version of get_order */ -static inline __attribute_const__ int get_order(unsigned long size) +/* + * Runtime evaluation of get_order() + */ +static inline __attribute_const__ +int __get_order(unsigned long size) { int order; - size = (size - 1) >> (PAGE_SHIFT - 1); - order = -1; - do { - size >>= 1; - order++; - } while (size); + size--; + size >>= PAGE_SHIFT; +#if BITS_PER_LONG == 32 + order = fls(size); +#else + order = fls64(size); +#endif return order; } +/** + * get_order - Determine the allocation order of a memory size + * @size: The size for which to get the order + * + * Determine the allocation order of a particular sized block of memory. This + * is on a logarithmic scale, where: + * + * 0 -> 2^0 * PAGE_SIZE and below + * 1 -> 2^1 * PAGE_SIZE to 2^0 * PAGE_SIZE + 1 + * 2 -> 2^2 * PAGE_SIZE to 2^1 * PAGE_SIZE + 1 + * 3 -> 2^3 * PAGE_SIZE to 2^2 * PAGE_SIZE + 1 + * 4 -> 2^4 * PAGE_SIZE to 2^3 * PAGE_SIZE + 1 + * ... + * + * The order returned is used to find the smallest allocation granule required + * to hold an object of the specified size. + * + * The result is undefined if the size is 0. + * + * This function may be used to initialise variables with compile time + * evaluations of constants. + */ +#define get_order(n) \ +( \ + __builtin_constant_p(n) ? ( \ + ((n) == 0UL) ? BITS_PER_LONG - PAGE_SHIFT : \ + (((n) < (1UL << PAGE_SHIFT)) ? 0 : \ + ilog2((n) - 1) - PAGE_SHIFT + 1) \ + ) : \ + __get_order(n) \ +) + #endif /* __ASSEMBLY__ */ #endif /* __ASM_GENERIC_GETORDER_H */ |