There are no dependencies to asm/i387.h. Instead, if including only
xsave.h the following error occurs:
.../arch/x86/include/asm/i387.h:110: error: ‘XSTATE_FP’ undeclared (first use in this function)
.../arch/x86/include/asm/i387.h:110: error: (Each undeclared identifier is reported only once
.../arch/x86/include/asm/i387.h:110: error: for each function it appears in.)
This patch fixes this.
Signed-off-by: Robert Richter <robert.richter@amd.com>
LKML-Reference: <1279651857-24639-2-git-send-email-robert.richter@amd.com>
Acked-by: Suresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
xsaveopt is a more optimized form of xsave specifically designed
for the context switch usage. xsaveopt doesn't save the state that's not
modified from the prior xrstor. And if a specific feature state gets
modified to the init state, then xsaveopt just updates the header bit
in the xsave memory layout without updating the corresponding memory
layout.
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
LKML-Reference: <20100719230205.604014179@sbs-t61.sc.intel.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
With xsaveopt, if a processor implementation discern that a processor state
component is in its initialized state it may modify the corresponding bit in
the xsave_hdr.xstate_bv as '0', with out modifying the corresponding memory
layout. Hence wHile presenting the xstate information to the user, we always
ensure that the memory layout of a feature will be in the init state if the
corresponding header bit is zero. This ensures the consistency and avoids the
condition of the user seeing some some stale state in the memory layout during
signal handling, debugging etc.
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
LKML-Reference: <20100719230205.351459480@sbs-t61.sc.intel.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Currently all fpu state access is through tsk->thread.xstate. Since we wish
to generalize fpu access to non-task contexts, wrap the state in a new
'struct fpu' and convert existing access to use an fpu API.
Signal frame handlers are not converted to the API since they will remain
task context only things.
Signed-off-by: Avi Kivity <avi@redhat.com>
Acked-by: Suresh Siddha <suresh.b.siddha@intel.com>
LKML-Reference: <1273135546-29690-3-git-send-email-avi@redhat.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Add the xstate regset support which helps extend the kernel ptrace and the
core-dump interfaces to support AVX state etc.
This regset interface is designed to support all the future state that gets
supported using xsave/xrstor infrastructure.
Looking at the memory layout saved by "xsave", one can't say which state
is represented in the memory layout. This is because if a particular state is
in init state, in the xsave hdr it can be represented by bit '0'. And hence
we can't really say by the xsave header wether a state is in init state or
the state is not saved in the memory layout.
And hence the xsave memory layout available through this regset
interface uses SW usable bytes [464..511] to convey what state is represented
in the memory layout.
First 8 bytes of the sw_usable_bytes[464..467] will be set to OS enabled xstate
mask(which is same as the 64bit mask returned by the xgetbv's xCR0).
The note NT_X86_XSTATE represents the extended state information in the
core file, using the above mentioned memory layout.
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
LKML-Reference: <20100211195614.802495327@sbs-t61.sc.intel.com>
Signed-off-by: Hongjiu Lu <hjl.tools@gmail.com>
Cc: Roland McGrath <roland@redhat.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Impact: save/restore Intel-AVX state properly between tasks
Intel Advanced Vector Extensions (AVX) introduce 256-bit vector processing
capability. More about AVX at http://software.intel.com/sites/avx
Add OS support for YMM state management using xsave/xrstor infrastructure
to support AVX.
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
LKML-Reference: <1239402084.27006.8057.camel@localhost.localdomain>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
