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| author | Kan Liang <kan.liang@linux.intel.com> | 2020-07-03 05:49:27 -0700 |
|---|---|---|
| committer | Peter Zijlstra <peterz@infradead.org> | 2020-07-08 11:38:56 +0200 |
| commit | 50f408d96d4d1a945d2c50c5fd8ed400883edf0e (patch) | |
| tree | 4c3cd86d7697a86da65cacdc2765d076270a685b /arch/x86/include/asm/fpu | |
| parent | f0dccc9da4c0fda049e99326f85db8c242fd781f (diff) | |
| download | linux-stable-50f408d96d4d1a945d2c50c5fd8ed400883edf0e.tar.gz linux-stable-50f408d96d4d1a945d2c50c5fd8ed400883edf0e.tar.bz2 linux-stable-50f408d96d4d1a945d2c50c5fd8ed400883edf0e.zip | |
x86/fpu/xstate: Add helpers for LBR dynamic supervisor feature
The perf subsystem will only need to save/restore the LBR state.
However, the existing helpers save all supported supervisor states to a
kernel buffer, which will be unnecessary. Two helpers are introduced to
only save/restore requested dynamic supervisor states. The supervisor
features in XFEATURE_MASK_SUPERVISOR_SUPPORTED and
XFEATURE_MASK_SUPERVISOR_UNSUPPORTED mask cannot be saved/restored using
these helpers.
The helpers will be used in the following patch.
Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Dave Hansen <dave.hansen@intel.com>
Link: https://lkml.kernel.org/r/1593780569-62993-22-git-send-email-kan.liang@linux.intel.com
Diffstat (limited to 'arch/x86/include/asm/fpu')
| -rw-r--r-- | arch/x86/include/asm/fpu/xstate.h | 3 |
1 files changed, 3 insertions, 0 deletions
diff --git a/arch/x86/include/asm/fpu/xstate.h b/arch/x86/include/asm/fpu/xstate.h index 040c4d49bfcb..c029fce627cf 100644 --- a/arch/x86/include/asm/fpu/xstate.h +++ b/arch/x86/include/asm/fpu/xstate.h @@ -106,6 +106,9 @@ int copy_xstate_to_user(void __user *ubuf, struct xregs_state *xsave, unsigned i int copy_kernel_to_xstate(struct xregs_state *xsave, const void *kbuf); int copy_user_to_xstate(struct xregs_state *xsave, const void __user *ubuf); void copy_supervisor_to_kernel(struct xregs_state *xsave); +void copy_dynamic_supervisor_to_kernel(struct xregs_state *xstate, u64 mask); +void copy_kernel_to_dynamic_supervisor(struct xregs_state *xstate, u64 mask); + /* Validate an xstate header supplied by userspace (ptrace or sigreturn) */ int validate_user_xstate_header(const struct xstate_header *hdr); |