Commit 12b792e5 authored by Mark Brown's avatar Mark Brown Committed by Catalin Marinas
Browse files

arm64/fp: Add comments documenting the usage of state restore functions 



Add comments to help people figure out when fpsimd_bind_state_to_cpu() and
fpsimd_update_current_state() are used.

Signed-off-by: default avatarMark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20211207163250.1373542-1-broonie@kernel.org


Signed-off-by: default avatarCatalin Marinas <catalin.marinas@arm.com>
parent 386a7467

arch/arm64/kernel/fpsimd.c

+5 −2
Original line number Diff line number Diff line
@@ -1213,7 +1213,8 @@ void fpsimd_bind_state_to_cpu(struct user_fpsimd_state *st, void *sve_state, 
/*

 * Load the userland FPSIMD state of 'current' from memory, but only if the

 * FPSIMD state already held in the registers is /not/ the most recent FPSIMD

 * state of 'current'

 * state of 'current'.  This is called when we are preparing to return to

 * userspace to ensure that userspace sees a good register state.

 */

void fpsimd_restore_current_state(void)

{
@@ -1244,7 +1245,9 @@ void fpsimd_restore_current_state(void) 
/*

 * Load an updated userland FPSIMD state for 'current' from memory and set the

 * flag that indicates that the FPSIMD register contents are the most recent

 * FPSIMD state of 'current'

 * FPSIMD state of 'current'. This is used by the signal code to restore the

 * register state when returning from a signal handler in FPSIMD only cases,

 * any SVE context will be discarded.

 */

void fpsimd_update_current_state(struct user_fpsimd_state const *state)

{