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author | Edward Tomasz Napierala <trasz@FreeBSD.org> | 2020-10-05 18:46:14 +0000 |
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committer | Edward Tomasz Napierala <trasz@FreeBSD.org> | 2020-10-05 18:46:14 +0000 |
commit | 2622708419596b59bab640acf2d7319e6070ccd4 (patch) | |
tree | 6b4c3a7ffaf1d0f751748350d68762a1e1fa1286 | |
parent | f157761902001d0183aae593e9cc768b02e81bcf (diff) | |
download | src-2622708419596b59bab640acf2d7319e6070ccd4.tar.gz src-2622708419596b59bab640acf2d7319e6070ccd4.zip |
Tweak arm64's cpu_fetch_syscall_args(). This should make it possible
for the compiler to inline the memcpy().
Reviewed by: andrew
Sponsored by: DARPA
Differential Revision: https://reviews.freebsd.org/D26629
Notes
Notes:
svn path=/head/; revision=366456
-rw-r--r-- | sys/arm64/arm64/trap.c | 21 |
1 files changed, 11 insertions, 10 deletions
diff --git a/sys/arm64/arm64/trap.c b/sys/arm64/arm64/trap.c index f125025b0c61..05f08b90cdfe 100644 --- a/sys/arm64/arm64/trap.c +++ b/sys/arm64/arm64/trap.c @@ -123,30 +123,31 @@ int cpu_fetch_syscall_args(struct thread *td) { struct proc *p; - register_t *ap; + register_t *ap, *dst_ap; struct syscall_args *sa; - int nap; - nap = MAXARGS; p = td->td_proc; - ap = td->td_frame->tf_x; sa = &td->td_sa; + ap = td->td_frame->tf_x; + dst_ap = &sa->args[0]; sa->code = td->td_frame->tf_x[8]; - if (sa->code == SYS_syscall || sa->code == SYS___syscall) { + if (__predict_false(sa->code == SYS_syscall || sa->code == SYS___syscall)) { sa->code = *ap++; - nap--; + } else { + *dst_ap++ = *ap++; } - if (sa->code >= p->p_sysent->sv_size) + if (__predict_false(sa->code >= p->p_sysent->sv_size)) sa->callp = &p->p_sysent->sv_table[0]; else sa->callp = &p->p_sysent->sv_table[sa->code]; - memcpy(sa->args, ap, nap * sizeof(register_t)); - if (sa->callp->sy_narg > nap) - panic("ARM64TODO: Could we have more than %d args?", MAXARGS); + KASSERT(sa->callp->sy_narg <= nitems(sa->args), + ("Syscall %d takes too many arguments", sa->code)); + + memcpy(dst_ap, ap, (MAXARGS - 1) * sizeof(register_t)); td->td_retval[0] = 0; td->td_retval[1] = 0; |