diff options
| author | Ingo Molnar <mingo@kernel.org> | 2015-03-05 08:58:44 +0100 |
|---|---|---|
| committer | Ingo Molnar <mingo@kernel.org> | 2015-03-05 09:48:17 +0100 |
| commit | c709feda56886c38af3116254f84cbe6a78b3a5d (patch) | |
| tree | 1959bd574b6a2878f158fd90002401b455733ed9 /arch/x86/mm/init.c | |
| parent | c281b94570ab711fdf21e81bdfb3d79764492bcf (diff) | |
x86/mm/pat: Initialize __cachemode2pte_tbl[] and __pte2cachemode_tbl[] in a bit more readable fashion
The initialization of these two arrays is a bit difficult to follow:
restructure it optically so that a 2D structure shows which bit in
the PTE is set and which not.
Also improve on comments a bit.
No code or data changed:
# arch/x86/mm/init.o:
text data bss dec hex filename
4585 424 29776 34785 87e1 init.o.before
4585 424 29776 34785 87e1 init.o.after
md5:
a82e11ff58bcfd0af3a94662a701f65d init.o.before.asm
a82e11ff58bcfd0af3a94662a701f65d init.o.after.asm
Reviewed-by: Juergen Gross <jgross@suse.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Jan Beulich <JBeulich@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Luis R. Rodriguez <mcgrof@suse.com>
Cc: Toshi Kani <toshi.kani@hp.com>
Cc: linux-kernel@vger.kernel.org
Link: http://lkml.kernel.org/r/20150305082135.GB5969@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'arch/x86/mm/init.c')
| -rw-r--r-- | arch/x86/mm/init.c | 40 |
1 files changed, 22 insertions, 18 deletions
diff --git a/arch/x86/mm/init.c b/arch/x86/mm/init.c index 6dc85d51cd98..4469563f8c3b 100644 --- a/arch/x86/mm/init.c +++ b/arch/x86/mm/init.c @@ -29,29 +29,33 @@ /* * Tables translating between page_cache_type_t and pte encoding. - * Minimal supported modes are defined statically, modified if more supported - * cache modes are available. - * Index into __cachemode2pte_tbl is the cachemode. - * Index into __pte2cachemode_tbl are the caching attribute bits of the pte - * (_PAGE_PWT, _PAGE_PCD, _PAGE_PAT) at index bit positions 0, 1, 2. + * + * Minimal supported modes are defined statically, they are modified + * during bootup if more supported cache modes are available. + * + * Index into __cachemode2pte_tbl[] is the cachemode. + * + * Index into __pte2cachemode_tbl[] are the caching attribute bits of the pte + * (_PAGE_PWT, _PAGE_PCD, _PAGE_PAT) at index bit positions 0, 1, 2. */ uint16_t __cachemode2pte_tbl[_PAGE_CACHE_MODE_NUM] = { - [_PAGE_CACHE_MODE_WB] = 0, - [_PAGE_CACHE_MODE_WC] = _PAGE_PWT, - [_PAGE_CACHE_MODE_UC_MINUS] = _PAGE_PCD, - [_PAGE_CACHE_MODE_UC] = _PAGE_PCD | _PAGE_PWT, - [_PAGE_CACHE_MODE_WT] = _PAGE_PCD, - [_PAGE_CACHE_MODE_WP] = _PAGE_PCD, + [_PAGE_CACHE_MODE_WB ] = 0 | 0 , + [_PAGE_CACHE_MODE_WC ] = _PAGE_PWT | 0 , + [_PAGE_CACHE_MODE_UC_MINUS] = 0 | _PAGE_PCD, + [_PAGE_CACHE_MODE_UC ] = _PAGE_PWT | _PAGE_PCD, + [_PAGE_CACHE_MODE_WT ] = 0 | _PAGE_PCD, + [_PAGE_CACHE_MODE_WP ] = 0 | _PAGE_PCD, }; EXPORT_SYMBOL(__cachemode2pte_tbl); + uint8_t __pte2cachemode_tbl[8] = { - [__pte2cm_idx(0)] = _PAGE_CACHE_MODE_WB, - [__pte2cm_idx(_PAGE_PWT)] = _PAGE_CACHE_MODE_WC, - [__pte2cm_idx(_PAGE_PCD)] = _PAGE_CACHE_MODE_UC_MINUS, - [__pte2cm_idx(_PAGE_PWT | _PAGE_PCD)] = _PAGE_CACHE_MODE_UC, - [__pte2cm_idx(_PAGE_PAT)] = _PAGE_CACHE_MODE_WB, - [__pte2cm_idx(_PAGE_PWT | _PAGE_PAT)] = _PAGE_CACHE_MODE_WC, - [__pte2cm_idx(_PAGE_PCD | _PAGE_PAT)] = _PAGE_CACHE_MODE_UC_MINUS, + [__pte2cm_idx( 0 | 0 | 0 )] = _PAGE_CACHE_MODE_WB, + [__pte2cm_idx(_PAGE_PWT | 0 | 0 )] = _PAGE_CACHE_MODE_WC, + [__pte2cm_idx( 0 | _PAGE_PCD | 0 )] = _PAGE_CACHE_MODE_UC_MINUS, + [__pte2cm_idx(_PAGE_PWT | _PAGE_PCD | 0 )] = _PAGE_CACHE_MODE_UC, + [__pte2cm_idx( 0 | 0 | _PAGE_PAT)] = _PAGE_CACHE_MODE_WB, + [__pte2cm_idx(_PAGE_PWT | 0 | _PAGE_PAT)] = _PAGE_CACHE_MODE_WC, + [__pte2cm_idx(0 | _PAGE_PCD | _PAGE_PAT)] = _PAGE_CACHE_MODE_UC_MINUS, [__pte2cm_idx(_PAGE_PWT | _PAGE_PCD | _PAGE_PAT)] = _PAGE_CACHE_MODE_UC, }; EXPORT_SYMBOL(__pte2cachemode_tbl); |