- 19 May, 2015 40 commits
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Ingo Molnar authored
Rename this function in line with the new FPU nomenclature. Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@kernel.org>
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Ingo Molnar authored
So this function still had ancient language about 'saving current math information' - but we haven't been doing lazy FPU saves for quite some time, we are doing lazy FPU restores. Also remove IRQ13 related comment, which we don't support anymore either. Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@kernel.org>
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Ingo Molnar authored
Move the naming in line with existing names, so that we now have: copy_fpregs_to_fpstate() copy_fpstate_to_sigframe() copy_fpregs_to_sigframe() ... where each function does what its name suggests. Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@kernel.org>
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Ingo Molnar authored
Standardize the naming of save_xstate_sig() by renaming it to copy_fpstate_to_sigframe(): this tells us at a glance that the function copies an FPU fpstate to a signal frame. This naming also follows the naming of copy_fpregs_to_fpstate(). Don't put 'xstate' into the name: since this is a generic name, it's expected that the function is able to handle xstate frames as well, beyond legacy frames. xstate used to be the odd case in the x86 FPU code - now it's the common case. Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@kernel.org>
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Ingo Molnar authored
Currently fpstate_sanitize_xstate() has a task_struct input parameter, but it only uses the fpu structure from it - so pass in a 'struct fpu' pointer only and update all call sites. Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@kernel.org>
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Ingo Molnar authored
Remove the extra layer of __fpstate_sanitize_xstate(): if (!use_xsaveopt()) return; __fpstate_sanitize_xstate(tsk); and move the check for use_xsaveopt() into fpstate_sanitize_xstate(). In general we optimize for the presence of CPU features, not for the absence of them. Furthermore there's little point in this inlining, as the call sites are not super hot code paths. Doing this uninlining shrinks the code a bit: text data bss dec hex filename 14108751 2573624 1634304 18316679 1177d87 vmlinux.before 14108627 2573624 1634304 18316555 1177d0b vmlinux.after Also remove a pointless '!fx' check from fpstate_sanitize_xstate(). Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@kernel.org>
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Ingo Molnar authored
So the sanitize_i387_state() function has the following purpose: on CPUs that support optimized xstate saving instructions, an FPU fpstate might end up having partially uninitialized data. This function initializes that data. Note that the function name is a misnomer and confusing on two levels, not only is it not i387 specific at all, but it is the exact opposite: it only matters on xstate CPUs. So rename sanitize_i387_state() and __sanitize_i387_state() to fpstate_sanitize_xstate() and __fpstate_sanitize_xstate(), to clearly express the purpose and usage of the function. We'll further clean up this function in the next patch. Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@kernel.org>
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Ingo Molnar authored
Now that all FPU internals using drivers are converted to public APIs, move xcr.h's definitions into fpu/internal.h and remove xcr.h. Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@kernel.org>
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Ingo Molnar authored
This file only uses the public FPU APIs, so remove the xcr.h, fpu/xstate.h and fpu/internal.h headers and add the fpu/api.h include. Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@kernel.org>
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Ingo Molnar authored
Use the new 'cpu_has_xfeatures()' function to query AVX CPU support. This has the following advantages to the driver: - Decouples the driver from FPU internals: it's now only using <asm/fpu/api.h>. - Removes detection complexity from the driver, no more raw XGETBV instruction - Shrinks the code a bit. - Standardizes feature name error message printouts across drivers There are also advantages to the x86 FPU code: once all drivers are decoupled from internals we can move them out of common headers and we'll also be able to remove xcr.h. Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@kernel.org>
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Ingo Molnar authored
Use the new 'cpu_has_xfeatures()' function to query AVX CPU support. This has the following advantages to the driver: - Decouples the driver from FPU internals: it's now only using <asm/fpu/api.h>. - Removes detection complexity from the driver, no more raw XGETBV instruction - Shrinks the code a bit. - Standardizes feature name error message printouts across drivers There are also advantages to the x86 FPU code: once all drivers are decoupled from internals we can move them out of common headers and we'll also be able to remove xcr.h. Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@kernel.org>
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Ingo Molnar authored
Use the new 'cpu_has_xfeatures()' function to query AVX CPU support. This has the following advantages to the driver: - Decouples the driver from FPU internals: it's now only using <asm/fpu/api.h>. - Removes detection complexity from the driver, no more raw XGETBV instruction - Shrinks the code a bit. - Standardizes feature name error message printouts across drivers There are also advantages to the x86 FPU code: once all drivers are decoupled from internals we can move them out of common headers and we'll also be able to remove xcr.h. Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@kernel.org>
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Ingo Molnar authored
Use the new 'cpu_has_xfeatures()' function to query AVX CPU support. This has the following advantages to the driver: - Decouples the driver from FPU internals: it's now only using <asm/fpu/api.h>. - Removes detection complexity from the driver, no more raw XGETBV instruction - Shrinks the code a bit. - Standardizes feature name error message printouts across drivers There are also advantages to the x86 FPU code: once all drivers are decoupled from internals we can move them out of common headers and we'll also be able to remove xcr.h. Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@kernel.org>
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Ingo Molnar authored
Use the new 'cpu_has_xfeatures()' function to query AVX CPU support. This has the following advantages to the driver: - Decouples the driver from FPU internals: it's now only using <asm/fpu/api.h>. - Removes detection complexity from the driver, no more raw XGETBV instruction - Shrinks the code a bit. - Standardizes feature name error message printouts across drivers There are also advantages to the x86 FPU code: once all drivers are decoupled from internals we can move them out of common headers and we'll also be able to remove xcr.h. Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@kernel.org>
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Ingo Molnar authored
Use the new 'cpu_has_xfeatures()' function to query AVX CPU support. This has the following advantages to the driver: - Decouples the driver from FPU internals: it's now only using <asm/fpu/api.h>. - Removes detection complexity from the driver, no more raw XGETBV instruction - Shrinks the code a bit. - Standardizes feature name error message printouts across drivers There are also advantages to the x86 FPU code: once all drivers are decoupled from internals we can move them out of common headers and we'll also be able to remove xcr.h. Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@kernel.org>
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Ingo Molnar authored
Use the new 'cpu_has_xfeatures()' function to query AVX CPU support. This has the following advantages to the driver: - Decouples the driver from FPU internals: it's now only using <asm/fpu/api.h>. - Removes detection complexity from the driver, no more raw XGETBV instruction - Shrinks the code a bit. - Standardizes feature name error message printouts across drivers There are also advantages to the x86 FPU code: once all drivers are decoupled from internals we can move them out of common headers and we'll also be able to remove xcr.h. Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@kernel.org>
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Ingo Molnar authored
Use the new 'cpu_has_xfeatures()' function to query AVX CPU support. This has the following advantages to the driver: - Decouples the driver from FPU internals: it's now only using <asm/fpu/api.h>. - Removes detection complexity from the driver, no more raw XGETBV instruction - Shrinks the code a bit. - Standardizes feature name error message printouts across drivers There are also advantages to the x86 FPU code: once all drivers are decoupled from internals we can move them out of common headers and we'll also be able to remove xcr.h. Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@kernel.org>
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Ingo Molnar authored
Use the new 'cpu_has_xfeatures()' function to query AVX CPU support. This has the following advantages to the driver: - Decouples the driver from FPU internals: it's now only using <asm/fpu/api.h>. - Removes detection complexity from the driver, no more raw XGETBV instruction - Shrinks the code a bit. - Standardizes feature name error message printouts across drivers There are also advantages to the x86 FPU code: once all drivers are decoupled from internals we can move them out of common headers and we'll also be able to remove xcr.h. Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@kernel.org>
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Ingo Molnar authored
Use the new 'cpu_has_xfeatures()' function to query AVX CPU support. This has the following advantages to the driver: - Decouples the driver from FPU internals: it's now only using <asm/fpu/api.h>. - Removes detection complexity from the driver, no more raw XGETBV instruction - Shrinks the code a bit: text data bss dec hex filename 2128 2896 0 5024 13a0 camellia_aesni_avx_glue.o.before 2067 2896 0 4963 1363 camellia_aesni_avx_glue.o.after - Standardizes feature name error message printouts across drivers There are also advantages to the x86 FPU code: once all drivers are decoupled from internals we can move them out of common headers and we'll also be able to remove xcr.h. Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@kernel.org>
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Ingo Molnar authored
So xsave.h is an internal header that FPU using drivers commonly include, to get access to the xstate feature names, amongst other things. Move these type definitions to fpu/fpu.h to allow simplification of FPU using driver code. Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@kernel.org>
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Ingo Molnar authored
Transform the xstate masks into an enumerated list of xfeature bits. This removes the hard coding of XFEATURES_NR_MAX. Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@kernel.org>
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Ingo Molnar authored
We do a boot time printout of xfeatures in print_xstate_features(), simplify this code to make use of the recently introduced cpu_has_xfeature() method. Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@kernel.org>
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Ingo Molnar authored
A lot of FPU using driver code is querying complex CPU features to be able to figure out whether a given set of xstate features is supported by the CPU or not. Introduce a simplified API function that can be used on any CPU type to get this information. Also add an error string return pointer, so that the driver can print a meaningful error message with a standardized feature name. Also mark xfeatures_mask as __read_only. Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@kernel.org>
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Ingo Molnar authored
Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@kernel.org>
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Ingo Molnar authored
'xsave' is an x86 instruction name to most people - but xsave.h is about a lot more than just the XSAVE instruction: it includes definitions and support, both internal and external, related to xstate and xfeatures support. As a first step in cleaning up the various xstate uses rename this header to 'fpu/xstate.h' to better reflect what this header file is about. Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@kernel.org>
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Ingo Molnar authored
The current fpu_copy() code on lazy switching CPUs always saves into the current fpstate and then copies it over into the child context: preempt_disable(); if (!copy_fpregs_to_fpstate(src_fpu)) fpregs_deactivate(src_fpu); preempt_enable(); memcpy(&dst_fpu->state, &src_fpu->state, xstate_size); That memcpy() can be avoided on all lazy switching setups except really old FNSAVE-only systems: change fpu_copy() to directly save into the child context, for both the lazy and the eager context switching case. Note that we still have to do a memcpy() back into the parent context in the FNSAVE case, but this won't be executed on the majority of x86 systems that got built in the last 10 years or so. Reviewed-by: Borislav Petkov <bp@alien8.de> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@kernel.org>
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Ingo Molnar authored
Optimize fpu_copy() a bit by expanding the ->fpstate_active == 1 portion of fpu__save() into it. ( The main purpose of this change is to enable another, larger optimization that will be done in the next patch. ) Reviewed-by: Borislav Petkov <bp@alien8.de> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@kernel.org>
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Ingo Molnar authored
So fpu__save() does this currently: copy_fpregs_to_fpstate(fpu); if (!use_eager_fpu()) fpregs_deactivate(fpu); ... which deactivates the FPU on lazy switching systems unconditionally. Both usecases of fpu__save() use this function to save the FPU state into a fpstate: fork()/clone() and math error signal handling. The unconditional disabling of FPU registers in the lazy switching case is probably a mistaken conversion of old FNSAVE code (that had to disable FPU registers). So speed up this code by only disabling FPU registers when absolutely necessary: when indicated by the copy_fpregs_to_fpstate() return code: if (!copy_fpregs_to_fpstate(fpu)) fpregs_deactivate(fpu); Reviewed-by: Borislav Petkov <bp@alien8.de> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@kernel.org>
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Ingo Molnar authored
Factor out a common call. Reviewed-by: Borislav Petkov <bp@alien8.de> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@kernel.org>
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Ingo Molnar authored
The current implementation of __save_fpu(): if (use_xsave()) { xsave_state(&fpu->state.xsave); } else { fpu_fxsave(fpu); } Is actually a simplified version of copy_fpregs_to_fpstate(), if use_eager_fpu() is true. But all call sites of __save_fpu() call it only it when use_eager_fpu() is true. So we can eliminate __save_fpu() altogether and use the standard copy_fpregs_to_fpstate() function. This cleans up the code by making it use fewer variants of FPU register saving. Reviewed-by: Borislav Petkov <bp@alien8.de> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@kernel.org>
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Ingo Molnar authored
__save_fpu() has this pattern: if (unlikely(system_state == SYSTEM_BOOTING)) xsave_state_booting(&fpu->state.xsave); else xsave_state(&fpu->state.xsave); ... but it does not actually get called during system bootup. So remove the complication and always call xsave_state(). To make sure this assumption is correct, add a WARN_ONCE() debug check to xsave_state(). Reviewed-by: Borislav Petkov <bp@alien8.de> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@kernel.org>
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Ingo Molnar authored
We have repeat patterns of: if (!use_eager_fpu()) clts(); ... to activate FPU registers, and: if (!use_eager_fpu()) stts(); ... to deactivate them. Encapsulate these in: __fpregs_activate_hw(); __fpregs_activate_hw(); and use them accordingly. Doing this synchronizes the idiom with the fpu->fpregs_active software-flag's handling functions, creating clear patterns of: __fpregs_activate_hw(); __fpregs_activate(fpu); etc., which improves readability. Reviewed-by: Borislav Petkov <bp@alien8.de> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@kernel.org>
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Ingo Molnar authored
In line with the fpstate_activate() change, name fpu__unlazy_stopped() in a similar fashion as well: its purpose is to make the fpstate of a stopped task the current and active FPU context, which may require unlazying and initialization. The unlazying is just part of the job, the main concept is to make the fpstate active. Also clarify the function's description to clarify its exact usage and the background behind it all. Reviewed-by: Borislav Petkov <bp@alien8.de> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@kernel.org>
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Ingo Molnar authored
Now that fpstate_init_curr() is not doing implicit allocations anymore, almost all uses of it involve a very simple pattern: if (!fpu->fpstate_active) fpstate_init_curr(fpu); which is basically activating the FPU fpstate if it was not active before. So propagate the check into the function itself, and rename the function according to its new purpose: fpu__activate_curr(fpu); Reviewed-by: Borislav Petkov <bp@alien8.de> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@kernel.org>
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Ingo Molnar authored
Now that fpstate_init() cannot fail the error return of fx_init() has lost its purpose. Eliminate the error return and propagate this change to all callers. Reviewed-by: Borislav Petkov <bp@alien8.de> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@kernel.org>
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Ingo Molnar authored
Now that FPU contexts are always allocated, fpu__unlazy_stopped() cannot fail. Remove its error return and propagate the changes to the callers. Reviewed-by: Borislav Petkov <bp@alien8.de> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@kernel.org>
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Ingo Molnar authored
Now that there are no FPU context allocations, rename fpstate_alloc_init() to fpstate_init_curr(), to signal that it initializes the fpstate and marks it active, for the current task. Reviewed-by: Borislav Petkov <bp@alien8.de> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@kernel.org>
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Ingo Molnar authored
Remove the failure code and propagate this down to callers. Note that this function still has an 'init' aspect, which must be called. Reviewed-by: Borislav Petkov <bp@alien8.de> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@kernel.org>
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Ingo Molnar authored
Now that we always allocate the FPU context as part of task_struct there's no need for separate allocations - remove them and their primary failure handling code. ( Note that there's still secondary error codes that have become superfluous, those will be removed in separate patches. ) Move the somewhat misplaced setup_xstate_comp() call to the core. Reviewed-by: Borislav Petkov <bp@alien8.de> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@kernel.org>
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Ingo Molnar authored
So 6 years ago we made the FPU fpstate dynamically allocated: aa283f49 ("x86, fpu: lazy allocation of FPU area - v5") 61c4628b ("x86, fpu: split FPU state from task struct - v5") In hindsight this was a mistake: - it complicated context allocation failure handling, such as: /* kthread execs. TODO: cleanup this horror. */ if (WARN_ON(fpstate_alloc_init(fpu))) force_sig(SIGKILL, tsk); - it caused us to enable irqs in fpu__restore(): local_irq_enable(); /* * does a slab alloc which can sleep */ if (fpstate_alloc_init(fpu)) { /* * ran out of memory! */ do_group_exit(SIGKILL); return; } local_irq_disable(); - it (slightly) slowed down task creation/destruction by adding slab allocation/free pattens. - it made access to context contents (slightly) slower by adding one more pointer dereference. The motivation for the dynamic allocation was two-fold: - reduce memory consumption by non-FPU tasks - allocate and handle only the necessary amount of context for various XSAVE processors that have varying hardware frame sizes. These days, with glibc using SSE memcpy by default and GCC optimizing for SSE/AVX by default, the scope of FPU using apps on an x86 system is much larger than it was 6 years ago. For example on a freshly installed Fedora 21 desktop system, with a recent kernel, all non-kthread tasks have used the FPU shortly after bootup. Also, even modern embedded x86 CPUs try to support the latest vector instruction set - so they'll too often use the larger xstate frame sizes. So remove the dynamic allocation complication by embedding the FPU fpstate in task_struct again. This should make the FPU a lot more accessible to all sorts of atomic contexts. We could still optimize for the xstate frame size in the future, by moving the state structure to the last element of task_struct, and allocating only a part of that. This change is kept minimal by still keeping the ctx_alloc()/free() routines (that now do nothing substantial) - we'll remove them in the following patches. Reviewed-by: Borislav Petkov <bp@alien8.de> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@kernel.org>
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