From 8884b7bd7e52de20a801c5f457954ed212c0f625 Mon Sep 17 00:00:00 2001 From: Dave Martin Date: Wed, 6 Dec 2017 16:45:46 +0000 Subject: arm64: fpsimd: Abstract out binding of task's fpsimd context to the cpu. There is currently some duplicate logic to associate current's FPSIMD context with the cpu when loading FPSIMD state into the cpu regs. Subsequent patches will update that logic, so in order to ensure it only needs to be done in one place, this patch factors the relevant code out into a new function fpsimd_bind_to_cpu(). Signed-off-by: Dave Martin Reviewed-by: Ard Biesheuvel Signed-off-by: Will Deacon --- arch/arm64/kernel/fpsimd.c | 25 +++++++++++++++---------- 1 file changed, 15 insertions(+), 10 deletions(-) (limited to 'arch') diff --git a/arch/arm64/kernel/fpsimd.c b/arch/arm64/kernel/fpsimd.c index 5084e699447a..e330cc0b573d 100644 --- a/arch/arm64/kernel/fpsimd.c +++ b/arch/arm64/kernel/fpsimd.c @@ -991,6 +991,18 @@ void fpsimd_signal_preserve_current_state(void) sve_to_fpsimd(current); } +/* + * Associate current's FPSIMD context with this cpu + * Preemption must be disabled when calling this function. + */ +static void fpsimd_bind_to_cpu(void) +{ + struct fpsimd_state *st = ¤t->thread.fpsimd_state; + + __this_cpu_write(fpsimd_last_state, st); + st->cpu = smp_processor_id(); +} + /* * 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 @@ -1004,11 +1016,8 @@ void fpsimd_restore_current_state(void) local_bh_disable(); if (test_and_clear_thread_flag(TIF_FOREIGN_FPSTATE)) { - struct fpsimd_state *st = ¤t->thread.fpsimd_state; - task_fpsimd_load(); - __this_cpu_write(fpsimd_last_state, st); - st->cpu = smp_processor_id(); + fpsimd_bind_to_cpu(); } local_bh_enable(); @@ -1032,12 +1041,8 @@ void fpsimd_update_current_state(struct fpsimd_state *state) task_fpsimd_load(); - if (test_and_clear_thread_flag(TIF_FOREIGN_FPSTATE)) { - struct fpsimd_state *st = ¤t->thread.fpsimd_state; - - __this_cpu_write(fpsimd_last_state, st); - st->cpu = smp_processor_id(); - } + if (test_and_clear_thread_flag(TIF_FOREIGN_FPSTATE)) + fpsimd_bind_to_cpu(); local_bh_enable(); } -- cgit v1.2.3