From 8eda072e9d7c3429a372e3635dc5851f4a42dee1 Mon Sep 17 00:00:00 2001 From: Dave Hansen Date: Wed, 29 Jun 2016 13:01:10 -0700 Subject: [PATCH] x86/cpufeature: Add helper macro for mask check macros Every time we add a word to our cpu features, we need to add something like this in two places: (((bit)>>5)==16 && (1UL<<((bit)&31) & REQUIRED_MASK16)) The trick is getting the "16" in this case in both places. I've now screwed this up twice, so as pennance, I've come up with this patch to keep me and other poor souls from doing the same. I also commented the logic behind the bit manipulation showcased above. Signed-off-by: Dave Hansen Cc: Andy Lutomirski Cc: Borislav Petkov Cc: Brian Gerst Cc: Dave Hansen Cc: Denys Vlasenko Cc: H. Peter Anvin Cc: Josh Poimboeuf Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Thomas Gleixner Link: http://lkml.kernel.org/r/20160629200110.1BA8949E@viggo.jf.intel.com Signed-off-by: Ingo Molnar --- arch/x86/include/asm/cpufeature.h | 90 +++++++++++++++++-------------- 1 file changed, 50 insertions(+), 40 deletions(-) diff --git a/arch/x86/include/asm/cpufeature.h b/arch/x86/include/asm/cpufeature.h index 7b20720db3fa..1d2b69fc0ceb 100644 --- a/arch/x86/include/asm/cpufeature.h +++ b/arch/x86/include/asm/cpufeature.h @@ -49,48 +49,58 @@ extern const char * const x86_bug_flags[NBUGINTS*32]; #define test_cpu_cap(c, bit) \ test_bit(bit, (unsigned long *)((c)->x86_capability)) -#define REQUIRED_MASK_BIT_SET(bit) \ - ( (((bit)>>5)==0 && (1UL<<((bit)&31) & REQUIRED_MASK0 )) || \ - (((bit)>>5)==1 && (1UL<<((bit)&31) & REQUIRED_MASK1 )) || \ - (((bit)>>5)==2 && (1UL<<((bit)&31) & REQUIRED_MASK2 )) || \ - (((bit)>>5)==3 && (1UL<<((bit)&31) & REQUIRED_MASK3 )) || \ - (((bit)>>5)==4 && (1UL<<((bit)&31) & REQUIRED_MASK4 )) || \ - (((bit)>>5)==5 && (1UL<<((bit)&31) & REQUIRED_MASK5 )) || \ - (((bit)>>5)==6 && (1UL<<((bit)&31) & REQUIRED_MASK6 )) || \ - (((bit)>>5)==7 && (1UL<<((bit)&31) & REQUIRED_MASK7 )) || \ - (((bit)>>5)==8 && (1UL<<((bit)&31) & REQUIRED_MASK8 )) || \ - (((bit)>>5)==9 && (1UL<<((bit)&31) & REQUIRED_MASK9 )) || \ - (((bit)>>5)==10 && (1UL<<((bit)&31) & REQUIRED_MASK10)) || \ - (((bit)>>5)==11 && (1UL<<((bit)&31) & REQUIRED_MASK11)) || \ - (((bit)>>5)==12 && (1UL<<((bit)&31) & REQUIRED_MASK12)) || \ - (((bit)>>5)==13 && (1UL<<((bit)&31) & REQUIRED_MASK13)) || \ - (((bit)>>5)==14 && (1UL<<((bit)&31) & REQUIRED_MASK14)) || \ - (((bit)>>5)==15 && (1UL<<((bit)&31) & REQUIRED_MASK15)) || \ - (((bit)>>5)==16 && (1UL<<((bit)&31) & REQUIRED_MASK16)) || \ - (((bit)>>5)==17 && (1UL<<((bit)&31) & REQUIRED_MASK17)) || \ - REQUIRED_MASK_CHECK || \ +/* + * There are 32 bits/features in each mask word. The high bits + * (selected with (bit>>5) give us the word number and the low 5 + * bits give us the bit/feature number inside the word. + * (1UL<<((bit)&31) gives us a mask for the feature_bit so we can + * see if it is set in the mask word. + */ +#define CHECK_BIT_IN_MASK_WORD(maskname, word, bit) \ + (((bit)>>5)==(word) && (1UL<<((bit)&31) & maskname##word )) + +#define REQUIRED_MASK_BIT_SET(feature_bit) \ + ( CHECK_BIT_IN_MASK_WORD(REQUIRED_MASK, 0, feature_bit) || \ + CHECK_BIT_IN_MASK_WORD(REQUIRED_MASK, 1, feature_bit) || \ + CHECK_BIT_IN_MASK_WORD(REQUIRED_MASK, 2, feature_bit) || \ + CHECK_BIT_IN_MASK_WORD(REQUIRED_MASK, 3, feature_bit) || \ + CHECK_BIT_IN_MASK_WORD(REQUIRED_MASK, 4, feature_bit) || \ + CHECK_BIT_IN_MASK_WORD(REQUIRED_MASK, 5, feature_bit) || \ + CHECK_BIT_IN_MASK_WORD(REQUIRED_MASK, 6, feature_bit) || \ + CHECK_BIT_IN_MASK_WORD(REQUIRED_MASK, 7, feature_bit) || \ + CHECK_BIT_IN_MASK_WORD(REQUIRED_MASK, 8, feature_bit) || \ + CHECK_BIT_IN_MASK_WORD(REQUIRED_MASK, 9, feature_bit) || \ + CHECK_BIT_IN_MASK_WORD(REQUIRED_MASK, 10, feature_bit) || \ + CHECK_BIT_IN_MASK_WORD(REQUIRED_MASK, 11, feature_bit) || \ + CHECK_BIT_IN_MASK_WORD(REQUIRED_MASK, 12, feature_bit) || \ + CHECK_BIT_IN_MASK_WORD(REQUIRED_MASK, 13, feature_bit) || \ + CHECK_BIT_IN_MASK_WORD(REQUIRED_MASK, 14, feature_bit) || \ + CHECK_BIT_IN_MASK_WORD(REQUIRED_MASK, 15, feature_bit) || \ + CHECK_BIT_IN_MASK_WORD(REQUIRED_MASK, 16, feature_bit) || \ + CHECK_BIT_IN_MASK_WORD(REQUIRED_MASK, 17, feature_bit) || \ + REQUIRED_MASK_CHECK || \ BUILD_BUG_ON_ZERO(NCAPINTS != 18)) -#define DISABLED_MASK_BIT_SET(bit) \ - ( (((bit)>>5)==0 && (1UL<<((bit)&31) & DISABLED_MASK0 )) || \ - (((bit)>>5)==1 && (1UL<<((bit)&31) & DISABLED_MASK1 )) || \ - (((bit)>>5)==2 && (1UL<<((bit)&31) & DISABLED_MASK2 )) || \ - (((bit)>>5)==3 && (1UL<<((bit)&31) & DISABLED_MASK3 )) || \ - (((bit)>>5)==4 && (1UL<<((bit)&31) & DISABLED_MASK4 )) || \ - (((bit)>>5)==5 && (1UL<<((bit)&31) & DISABLED_MASK5 )) || \ - (((bit)>>5)==6 && (1UL<<((bit)&31) & DISABLED_MASK6 )) || \ - (((bit)>>5)==7 && (1UL<<((bit)&31) & DISABLED_MASK7 )) || \ - (((bit)>>5)==8 && (1UL<<((bit)&31) & DISABLED_MASK8 )) || \ - (((bit)>>5)==9 && (1UL<<((bit)&31) & DISABLED_MASK9 )) || \ - (((bit)>>5)==10 && (1UL<<((bit)&31) & DISABLED_MASK10)) || \ - (((bit)>>5)==11 && (1UL<<((bit)&31) & DISABLED_MASK11)) || \ - (((bit)>>5)==12 && (1UL<<((bit)&31) & DISABLED_MASK12)) || \ - (((bit)>>5)==13 && (1UL<<((bit)&31) & DISABLED_MASK13)) || \ - (((bit)>>5)==14 && (1UL<<((bit)&31) & DISABLED_MASK14)) || \ - (((bit)>>5)==15 && (1UL<<((bit)&31) & DISABLED_MASK15)) || \ - (((bit)>>5)==16 && (1UL<<((bit)&31) & DISABLED_MASK16)) || \ - (((bit)>>5)==17 && (1UL<<((bit)&31) & DISABLED_MASK17)) || \ - DISABLED_MASK_CHECK || \ +#define DISABLED_MASK_BIT_SET(feature_bit) \ + ( CHECK_BIT_IN_MASK_WORD(DISABLED_MASK, 0, feature_bit) || \ + CHECK_BIT_IN_MASK_WORD(DISABLED_MASK, 1, feature_bit) || \ + CHECK_BIT_IN_MASK_WORD(DISABLED_MASK, 2, feature_bit) || \ + CHECK_BIT_IN_MASK_WORD(DISABLED_MASK, 3, feature_bit) || \ + CHECK_BIT_IN_MASK_WORD(DISABLED_MASK, 4, feature_bit) || \ + CHECK_BIT_IN_MASK_WORD(DISABLED_MASK, 5, feature_bit) || \ + CHECK_BIT_IN_MASK_WORD(DISABLED_MASK, 6, feature_bit) || \ + CHECK_BIT_IN_MASK_WORD(DISABLED_MASK, 7, feature_bit) || \ + CHECK_BIT_IN_MASK_WORD(DISABLED_MASK, 8, feature_bit) || \ + CHECK_BIT_IN_MASK_WORD(DISABLED_MASK, 9, feature_bit) || \ + CHECK_BIT_IN_MASK_WORD(DISABLED_MASK, 10, feature_bit) || \ + CHECK_BIT_IN_MASK_WORD(DISABLED_MASK, 11, feature_bit) || \ + CHECK_BIT_IN_MASK_WORD(DISABLED_MASK, 12, feature_bit) || \ + CHECK_BIT_IN_MASK_WORD(DISABLED_MASK, 13, feature_bit) || \ + CHECK_BIT_IN_MASK_WORD(DISABLED_MASK, 14, feature_bit) || \ + CHECK_BIT_IN_MASK_WORD(DISABLED_MASK, 15, feature_bit) || \ + CHECK_BIT_IN_MASK_WORD(DISABLED_MASK, 16, feature_bit) || \ + CHECK_BIT_IN_MASK_WORD(DISABLED_MASK, 17, feature_bit) || \ + DISABLED_MASK_CHECK || \ BUILD_BUG_ON_ZERO(NCAPINTS != 18)) #define cpu_has(c, bit) \ -- 2.20.1