Add new aux vector entries for cache size and shape #57

Section 4.1.2.3 should reflect this recent new agreement between glibc and the kernel:

/*

AT_*CACHEBSIZE above represent the cache block size which is
the size that is affected by the cache management instructions.
It doesn't nececssarily matches the cache line size which is
more of a performance tuning hint. Additionally the latter can
be different for the different cache levels.
The set of entries below represent more extensive information
about the caches, in the form of two entry per cache type,
one entry containing the cache size in bytes, and the other
containing the cache line size in bytes in the bottom 16 bits
and the cache associativity in the next 16 bits.
The associativity is such that if N is the 16-bit value, the
cache is N way set associative. A value if 0xffff means fully
associative, a value of 1 means directly mapped.
For all these fields, a value of 0 means that the information
is not known.
*/

#define AT_L1I_CACHESIZE 40
#define AT_L1I_CACHESHAPE 41
#define AT_L1D_CACHESIZE 42
#define AT_L1D_CACHESHAPE 43
#define AT_L2_CACHESIZE 44
#define AT_L2_CACHESHAPE 45
#define AT_L3_CACHESIZE 46
#define AT_L3_CACHESHAPE 47

Section 4.1.2.3 should reflect this recent new agreement between glibc and the kernel: /* * AT_*CACHEBSIZE above represent the cache *block* size which is * the size that is affected by the cache management instructions. * * It doesn't nececssarily matches the cache *line* size which is * more of a performance tuning hint. Additionally the latter can * be different for the different cache levels. * * The set of entries below represent more extensive information * about the caches, in the form of two entry per cache type, * one entry containing the cache size in bytes, and the other * containing the cache line size in bytes in the bottom 16 bits * and the cache associativity in the next 16 bits. * * The associativity is such that if N is the 16-bit value, the * cache is N way set associative. A value if 0xffff means fully * associative, a value of 1 means directly mapped. * * For all these fields, a value of 0 means that the information * is not known. */ #define AT_L1I_CACHESIZE 40 #define AT_L1I_CACHESHAPE 41 #define AT_L1D_CACHESIZE 42 #define AT_L1D_CACHESHAPE 43 #define AT_L2_CACHESIZE 44 #define AT_L2_CACHESHAPE 45 #define AT_L3_CACHESIZE 46 #define AT_L3_CACHESHAPE 47

Tulio reported an issue with Ben's patches on the linuxppc-dev@lists.ozlabs.org
list:

These names will clash with the other ones defined by alpha and sh:

/* Shapes of the caches. Bits 0-3 contains associativity; bits 4-7 contains
log2 of line size; mask those to get cache size. */
#define AT_L1I_CACHESHAPE 34
#define AT_L1D_CACHESHAPE 35
#define AT_L2_CACHESHAPE 36
#define AT_L3_CACHESHAPE 37

Tulio reported an issue with Ben's patches on the linuxppc-dev@lists.ozlabs.org list: -- These names will clash with the other ones defined by alpha and sh: /* Shapes of the caches. Bits 0-3 contains associativity; bits 4-7 contains log2 of line size; mask those to get cache size. */ #define AT_L1I_CACHESHAPE 34 #define AT_L1D_CACHESHAPE 35 #define AT_L2_CACHESHAPE 36 #define AT_L3_CACHESHAPE 37 --

Refer to this patch message for the final version:

https://lists.ozlabs.org/pipermail/linuxppc-dev/2017-January/152790.html

Refer to this patch message for the final version: https://lists.ozlabs.org/pipermail/linuxppc-dev/2017-January/152790.html

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Add new aux vector entries for cache size and shape #57

Tulio reported an issue with Ben's patches on the linuxppc-dev@lists.ozlabs.org list:

/* Shapes of the caches. Bits 0-3 contains associativity; bits 4-7 contains log2 of line size; mask those to get cache size. */ #define AT_L1I_CACHESHAPE 34 #define AT_L1D_CACHESHAPE 35 #define AT_L2_CACHESHAPE 36 #define AT_L3_CACHESHAPE 37

Tulio reported an issue with Ben's patches on the linuxppc-dev@lists.ozlabs.org
list:

/* Shapes of the caches. Bits 0-3 contains associativity; bits 4-7 contains
log2 of line size; mask those to get cache size. */
#define AT_L1I_CACHESHAPE 34
#define AT_L1D_CACHESHAPE 35
#define AT_L2_CACHESHAPE 36
#define AT_L3_CACHESHAPE 37