The following commit has been merged into the x86/core branch of tip: Commit-ID: 52354973573cc260ff2fc661cb28ff8eaa7b879b Gitweb: https://git.kernel.org/tip/52354973573cc260ff2fc661cb28ff8eaa7b879b Author: Peter Zijlstra <peterz@xxxxxxxxxxxxx> AuthorDate: Thu, 15 Sep 2022 13:11:26 +02:00 Committer: Peter Zijlstra <peterz@xxxxxxxxxxxxx> CommitterDate: Mon, 17 Oct 2022 16:41:14 +02:00 x86/asm: Provide ALTERNATIVE_3 Fairly straight forward adaptation/extention of ALTERNATIVE_2. Required for call depth tracking. Signed-off-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx> Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx> Signed-off-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx> Link: https://lore.kernel.org/r/20220915111147.787711192@xxxxxxxxxxxxx --- arch/x86/include/asm/alternative.h | 33 ++++++++++++++++++++++++++--- 1 file changed, 30 insertions(+), 3 deletions(-) diff --git a/arch/x86/include/asm/alternative.h b/arch/x86/include/asm/alternative.h index ef007fa..4c416b2 100644 --- a/arch/x86/include/asm/alternative.h +++ b/arch/x86/include/asm/alternative.h @@ -364,6 +364,7 @@ static inline int alternatives_text_reserved(void *start, void *end) #define old_len 141b-140b #define new_len1 144f-143f #define new_len2 145f-144f +#define new_len3 146f-145f /* * gas compatible max based on the idea from: @@ -371,7 +372,8 @@ static inline int alternatives_text_reserved(void *start, void *end) * * The additional "-" is needed because gas uses a "true" value of -1. */ -#define alt_max_short(a, b) ((a) ^ (((a) ^ (b)) & -(-((a) < (b))))) +#define alt_max_2(a, b) ((a) ^ (((a) ^ (b)) & -(-((a) < (b))))) +#define alt_max_3(a, b, c) (alt_max_2(alt_max_2(a, b), c)) /* @@ -383,8 +385,8 @@ static inline int alternatives_text_reserved(void *start, void *end) 140: \oldinstr 141: - .skip -((alt_max_short(new_len1, new_len2) - (old_len)) > 0) * \ - (alt_max_short(new_len1, new_len2) - (old_len)),0x90 + .skip -((alt_max_2(new_len1, new_len2) - (old_len)) > 0) * \ + (alt_max_2(new_len1, new_len2) - (old_len)),0x90 142: .pushsection .altinstructions,"a" @@ -401,6 +403,31 @@ static inline int alternatives_text_reserved(void *start, void *end) .popsection .endm +.macro ALTERNATIVE_3 oldinstr, newinstr1, feature1, newinstr2, feature2, newinstr3, feature3 +140: + \oldinstr +141: + .skip -((alt_max_3(new_len1, new_len2, new_len3) - (old_len)) > 0) * \ + (alt_max_3(new_len1, new_len2, new_len3) - (old_len)),0x90 +142: + + .pushsection .altinstructions,"a" + altinstruction_entry 140b,143f,\feature1,142b-140b,144f-143f + altinstruction_entry 140b,144f,\feature2,142b-140b,145f-144f + altinstruction_entry 140b,145f,\feature3,142b-140b,146f-145f + .popsection + + .pushsection .altinstr_replacement,"ax" +143: + \newinstr1 +144: + \newinstr2 +145: + \newinstr3 +146: + .popsection +.endm + /* If @feature is set, patch in @newinstr_yes, otherwise @newinstr_no. */ #define ALTERNATIVE_TERNARY(oldinstr, feature, newinstr_yes, newinstr_no) \ ALTERNATIVE_2 oldinstr, newinstr_no, X86_FEATURE_ALWAYS, \
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