From 0eaeafa10f3b2bd027e95859a6785d4c7fcc174c Mon Sep 17 00:00:00 2001 From: Christian Borntraeger Date: Wed, 7 May 2008 09:22:53 +0200 Subject: [S390] s390-kvm: leave sie context on work. Removes preemption requirement From: Martin Schwidefsky This patch fixes a bug with cpu bound guest on kvm-s390. Sometimes it was impossible to deliver a signal to a spinning guest. We used preemption as a circumvention. The preemption notifiers called vcpu_load, which checked for pending signals and triggered a host intercept. But even with preemption, a sigkill was not delivered immediately. This patch changes the low level host interrupt handler to check for the SIE instruction, if TIF_WORK is set. In that case we change the instruction pointer of the return PSW to rerun the vcpu_run loop. The kvm code sees an intercept reason 0 if that happens. This patch adds accounting for these types of intercept as well. The advantages: - works with and without preemption - signals are delivered immediately - much better host latencies without preemption Acked-by: Carsten Otte Signed-off-by: Christian Borntraeger Signed-off-by: Martin Schwidefsky --- include/asm-s390/kvm_host.h | 1 + 1 file changed, 1 insertion(+) (limited to 'include') diff --git a/include/asm-s390/kvm_host.h b/include/asm-s390/kvm_host.h index f8204a4f2e02..18cbd8a39796 100644 --- a/include/asm-s390/kvm_host.h +++ b/include/asm-s390/kvm_host.h @@ -104,6 +104,7 @@ struct sie_block { struct kvm_vcpu_stat { u32 exit_userspace; + u32 exit_null; u32 exit_external_request; u32 exit_external_interrupt; u32 exit_stop_request; -- cgit v1.2.2 From b499d76bfd78e900039155247e1c21bfdf807b7b Mon Sep 17 00:00:00 2001 From: Roland McGrath Date: Wed, 7 May 2008 09:22:57 +0200 Subject: [S390] compat ptrace cleanup This removes redundant arch code for generic ptrace requests already handled by ptrace_request and compat_ptrace_request. It simplifies things to just have the standard entry points, and use the generic compat_sys_ptrace. Signed-off-by: Roland McGrath Signed-off-by: Martin Schwidefsky --- include/asm-s390/ptrace.h | 2 ++ 1 file changed, 2 insertions(+) (limited to 'include') diff --git a/include/asm-s390/ptrace.h b/include/asm-s390/ptrace.h index 441d7c260857..d7d4e2eb3e6f 100644 --- a/include/asm-s390/ptrace.h +++ b/include/asm-s390/ptrace.h @@ -471,6 +471,8 @@ struct task_struct; extern void user_enable_single_step(struct task_struct *); extern void user_disable_single_step(struct task_struct *); +#define __ARCH_WANT_COMPAT_SYS_PTRACE + #define user_mode(regs) (((regs)->psw.mask & PSW_MASK_PSTATE) != 0) #define instruction_pointer(regs) ((regs)->psw.addr & PSW_ADDR_INSN) #define regs_return_value(regs)((regs)->gprs[2]) -- cgit v1.2.2 From 45e576b1c3d0020607b8666c0247164e92c7d719 Mon Sep 17 00:00:00 2001 From: Martin Schwidefsky Date: Wed, 7 May 2008 09:22:59 +0200 Subject: [S390] guest page hinting light Use the existing arch_alloc_page/arch_free_page callbacks to do the guest page state transitions between stable and unused. Acked-by: Rik van Riel Signed-off-by: Martin Schwidefsky --- include/asm-s390/page.h | 11 +++++++++++ include/asm-s390/system.h | 6 ++++++ 2 files changed, 17 insertions(+) (limited to 'include') diff --git a/include/asm-s390/page.h b/include/asm-s390/page.h index f0f4579eac13..12fd9c4f0f15 100644 --- a/include/asm-s390/page.h +++ b/include/asm-s390/page.h @@ -125,6 +125,17 @@ page_get_storage_key(unsigned long addr) return skey; } +#ifdef CONFIG_PAGE_STATES + +struct page; +void arch_free_page(struct page *page, int order); +void arch_alloc_page(struct page *page, int order); + +#define HAVE_ARCH_FREE_PAGE +#define HAVE_ARCH_ALLOC_PAGE + +#endif + #endif /* !__ASSEMBLY__ */ /* to align the pointer to the (next) page boundary */ diff --git a/include/asm-s390/system.h b/include/asm-s390/system.h index c819ae25a842..e0d4500d5f95 100644 --- a/include/asm-s390/system.h +++ b/include/asm-s390/system.h @@ -116,6 +116,12 @@ extern void pfault_fini(void); #define pfault_fini() do { } while (0) #endif /* CONFIG_PFAULT */ +#ifdef CONFIG_PAGE_STATES +extern void cmma_init(void); +#else +static inline void cmma_init(void) { } +#endif + #define finish_arch_switch(prev) do { \ set_fs(current->thread.mm_segment); \ account_vtime(prev); \ -- cgit v1.2.2