From d7635c7a49948f95eb196f39c1aeac20ac3c2ff6 Mon Sep 17 00:00:00 2001 From: Andrew Turner Date: Thu, 20 Apr 2017 13:56:30 +0000 Subject: [PATCH] Push loading curthread into assembly in the synchronous exception handlers. This will help investigating the performance impact of moving parts of the switch statement in do_el0_sync into assembly. Sponsored by: DARPA, AFRL --- sys/arm64/arm64/exception.S | 7 +++++-- sys/arm64/arm64/genassym.c | 1 + sys/arm64/arm64/trap.c | 42 +++++++++++++++---------------------- 3 files changed, 23 insertions(+), 27 deletions(-) diff --git a/sys/arm64/arm64/exception.S b/sys/arm64/arm64/exception.S index 432c4d48aca4..515d3fe3b368 100644 --- a/sys/arm64/arm64/exception.S +++ b/sys/arm64/arm64/exception.S @@ -143,7 +143,8 @@ __FBSDID("$FreeBSD$"); ENTRY(handle_el1h_sync) save_registers 1 - mov x0, sp + ldr x0, [x18, #PC_CURTHREAD] + mov x1, sp bl do_el1h_sync restore_registers 1 eret @@ -163,7 +164,9 @@ END(handle_el1h_error) ENTRY(handle_el0_sync) save_registers 0 - mov x0, sp + ldr x0, [x18, #PC_CURTHREAD] + mov x1, sp + str x1, [x0, #TD_FRAME] bl do_el0_sync do_ast restore_registers 0 diff --git a/sys/arm64/arm64/genassym.c b/sys/arm64/arm64/genassym.c index 8d75ffa0bfad..6d68d7532139 100644 --- a/sys/arm64/arm64/genassym.c +++ b/sys/arm64/arm64/genassym.c @@ -57,6 +57,7 @@ ASSYM(SF_UC, offsetof(struct sigframe, sf_uc)); ASSYM(TD_PCB, offsetof(struct thread, td_pcb)); ASSYM(TD_FLAGS, offsetof(struct thread, td_flags)); +ASSYM(TD_FRAME, offsetof(struct thread, td_frame)); ASSYM(TD_LOCK, offsetof(struct thread, td_lock)); ASSYM(TF_SIZE, sizeof(struct trapframe)); diff --git a/sys/arm64/arm64/trap.c b/sys/arm64/arm64/trap.c index 016632451ed0..c36ac206f331 100644 --- a/sys/arm64/arm64/trap.c +++ b/sys/arm64/arm64/trap.c @@ -72,8 +72,8 @@ __FBSDID("$FreeBSD$"); extern register_t fsu_intr_fault; /* Called from exception.S */ -void do_el1h_sync(struct trapframe *); -void do_el0_sync(struct trapframe *); +void do_el1h_sync(struct thread *, struct trapframe *); +void do_el0_sync(struct thread *, struct trapframe *); void do_el0_error(struct trapframe *); static void print_registers(struct trapframe *frame); @@ -130,23 +130,20 @@ cpu_fetch_syscall_args(struct thread *td, struct syscall_args *sa) #include "../../kern/subr_syscall.c" static void -svc_handler(struct trapframe *frame) +svc_handler(struct thread *td, struct trapframe *frame) { struct syscall_args sa; - struct thread *td; int error; - td = curthread; - error = syscallenter(td, &sa); syscallret(td, error, &sa); } static void -data_abort(struct trapframe *frame, uint64_t esr, uint64_t far, int lower) +data_abort(struct thread *td, struct trapframe *frame, uint64_t esr, + uint64_t far, int lower) { struct vm_map *map; - struct thread *td; struct proc *p; struct pcb *pcb; vm_prot_t ftype; @@ -167,7 +164,6 @@ data_abort(struct trapframe *frame, uint64_t esr, uint64_t far, int lower) } #endif - td = curthread; pcb = td->td_pcb; /* @@ -261,7 +257,7 @@ print_registers(struct trapframe *frame) } void -do_el1h_sync(struct trapframe *frame) +do_el1h_sync(struct thread *td, struct trapframe *frame) { uint32_t exception; uint64_t esr, far; @@ -276,14 +272,14 @@ do_el1h_sync(struct trapframe *frame) #endif CTR4(KTR_TRAP, - "do_el1_sync: curthread: %p, esr %lx, elr: %lx, frame: %p", - curthread, esr, frame->tf_elr, frame); + "do_el1_sync: curthread: %p, esr %lx, elr: %lx, frame: %p", td, + esr, frame->tf_elr, frame); switch(exception) { case EXCP_FP_SIMD: case EXCP_TRAP_FP: #ifdef VFP - if ((curthread->td_pcb->pcb_fpflags & PCB_FP_KERN) != 0) { + if ((td->td_pcb->pcb_fpflags & PCB_FP_KERN) != 0) { vfp_restore_state(); } else #endif @@ -297,7 +293,7 @@ do_el1h_sync(struct trapframe *frame) case EXCP_DATA_ABORT: far = READ_SPECIALREG(far_el1); intr_enable(); - data_abort(frame, esr, far, 0); + data_abort(td, frame, esr, far, 0); break; case EXCP_BRK: #ifdef KDTRACE_HOOKS @@ -338,9 +334,8 @@ el0_excp_unknown(struct trapframe *frame, uint64_t far) } void -do_el0_sync(struct trapframe *frame) +do_el0_sync(struct thread *td, struct trapframe *frame) { - struct thread *td; uint32_t exception; uint64_t esr, far; @@ -349,9 +344,6 @@ do_el0_sync(struct trapframe *frame) ("Invalid pcpu address from userland: %p (tpidr %lx)", get_pcpu(), READ_SPECIALREG(tpidr_el1))); - td = curthread; - td->td_frame = frame; - esr = frame->tf_esr; exception = ESR_ELx_EXCEPTION(esr); switch (exception) { @@ -364,8 +356,8 @@ do_el0_sync(struct trapframe *frame) intr_enable(); CTR4(KTR_TRAP, - "do_el0_sync: curthread: %p, esr %lx, elr: %lx, frame: %p", - curthread, esr, frame->tf_elr, frame); + "do_el0_sync: curthread: %p, esr %lx, elr: %lx, frame: %p", td, esr, + frame->tf_elr, frame); switch(exception) { case EXCP_FP_SIMD: @@ -377,12 +369,12 @@ do_el0_sync(struct trapframe *frame) #endif break; case EXCP_SVC: - svc_handler(frame); + svc_handler(td, frame); break; case EXCP_INSN_ABORT_L: case EXCP_DATA_ABORT_L: case EXCP_DATA_ABORT: - data_abort(frame, esr, far, 1); + data_abort(td, frame, esr, far, 1); break; case EXCP_UNKNOWN: el0_excp_unknown(frame, far); @@ -418,10 +410,10 @@ do_el0_sync(struct trapframe *frame) break; } - KASSERT((curthread->td_pcb->pcb_fpflags & ~PCB_FP_USERMASK) == 0, + KASSERT((td->td_pcb->pcb_fpflags & ~PCB_FP_USERMASK) == 0, ("Kernel VFP flags set while entering userspace")); KASSERT( - curthread->td_pcb->pcb_fpusaved == &curthread->td_pcb->pcb_fpustate, + td->td_pcb->pcb_fpusaved == &td->td_pcb->pcb_fpustate, ("Kernel VFP state in use when entering userspace")); }