[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index] [PATCH v2 3/4] x86/PV: avoid double stack reset during schedule tail handling
Invoking check_wakeup_from_wait() from assembly allows the new continue_pv_domain() to replace the prior continue_nonidle_domain() as the tail hook, eliminating an extra reset_stack_and_jump(). Signed-off-by: Jan Beulich <jbeulich@xxxxxxxx> Reviewed-by: Juergen Gross <jgross@xxxxxxxx> --- a/xen/arch/x86/pv/domain.c +++ b/xen/arch/x86/pv/domain.c @@ -110,12 +110,6 @@ static int parse_pcid(const char *s) return rc; } -static void noreturn continue_nonidle_domain(void) -{ - check_wakeup_from_wait(); - reset_stack_and_jump(ret_from_intr); -} - static int setup_compat_l4(struct vcpu *v) { struct page_info *pg; @@ -341,13 +335,14 @@ void pv_domain_destroy(struct domain *d) FREE_XENHEAP_PAGE(d->arch.pv.gdt_ldt_l1tab); } +void noreturn continue_pv_domain(void); int pv_domain_initialise(struct domain *d) { static const struct arch_csw pv_csw = { .from = paravirt_ctxt_switch_from, .to = paravirt_ctxt_switch_to, - .tail = continue_nonidle_domain, + .tail = continue_pv_domain, }; int rc = -ENOMEM; --- a/xen/arch/x86/x86_64/entry.S +++ b/xen/arch/x86/x86_64/entry.S @@ -557,8 +557,10 @@ ENTRY(dom_crash_sync_extable) .text /* No special register assumptions. */ -ENTRY(ret_from_intr) #ifdef CONFIG_PV +ENTRY(continue_pv_domain) + call check_wakeup_from_wait +ret_from_intr: GET_CURRENT(bx) testb $3, UREGS_cs(%rsp) jz restore_all_xen @@ -567,6 +569,7 @@ ENTRY(ret_from_intr) je test_all_events jmp compat_test_all_events #else +ret_from_intr: ASSERT_CONTEXT_IS_XEN jmp restore_all_xen #endif --- a/xen/include/asm-x86/asm_defns.h +++ b/xen/include/asm-x86/asm_defns.h @@ -23,7 +23,6 @@ asm ( "\t.equ CONFIG_INDIRECT_THUNK, " #include <asm/indirect_thunk_asm.h> #ifndef __ASSEMBLY__ -void noreturn ret_from_intr(void); /* * This output constraint should be used for any inline asm which has a "call"
|
![]() |
Lists.xenproject.org is hosted with RackSpace, monitoring our |