From 2ec16bc0fc7ab544f2d405fd4fdd0d717c5ec0c5 Mon Sep 17 00:00:00 2001 From: Ryan Thibodeaux Date: Fri, 22 Mar 2019 14:29:57 -0400 Subject: x86/xen: Add "xen_timer_slop" command line option Add a new command-line option "xen_timer_slop=" that sets the minimum delta of virtual Xen timers. This commit does not change the default timer slop value for virtual Xen timers. Lowering the timer slop value should improve the accuracy of virtual timers (e.g., better process dispatch latency), but it will likely increase the number of virtual timer interrupts (relative to the original slop setting). The original timer slop value has not changed since the introduction of the Xen-aware Linux kernel code. This commit provides users an opportunity to tune timer performance given the refinements to hardware and the Xen event channel processing. It also mirrors a feature in the Xen hypervisor - the "timer_slop" Xen command line option. [boris: updated comment describing TIMER_SLOP] Signed-off-by: Ryan Thibodeaux Reviewed-by: Boris Ostrovsky Signed-off-by: Boris Ostrovsky --- arch/x86/xen/time.c | 20 +++++++++++++++++--- 1 file changed, 17 insertions(+), 3 deletions(-) (limited to 'arch/x86') diff --git a/arch/x86/xen/time.c b/arch/x86/xen/time.c index 6e29794573b7..befbdd8b17f0 100644 --- a/arch/x86/xen/time.c +++ b/arch/x86/xen/time.c @@ -28,7 +28,7 @@ #include "xen-ops.h" -/* Xen may fire a timer up to this many ns early */ +/* Minimum amount of time until next clock event fires */ #define TIMER_SLOP 100000 static u64 xen_sched_clock_offset __read_mostly; @@ -212,7 +212,7 @@ static int xen_timerop_set_next_event(unsigned long delta, return 0; } -static const struct clock_event_device xen_timerop_clockevent = { +static struct clock_event_device xen_timerop_clockevent __ro_after_init = { .name = "xen", .features = CLOCK_EVT_FEAT_ONESHOT, @@ -273,7 +273,7 @@ static int xen_vcpuop_set_next_event(unsigned long delta, return ret; } -static const struct clock_event_device xen_vcpuop_clockevent = { +static struct clock_event_device xen_vcpuop_clockevent __ro_after_init = { .name = "xen", .features = CLOCK_EVT_FEAT_ONESHOT, @@ -570,3 +570,17 @@ void __init xen_hvm_init_time_ops(void) x86_platform.set_wallclock = xen_set_wallclock; } #endif + +/* Kernel parameter to specify Xen timer slop */ +static int __init parse_xen_timer_slop(char *ptr) +{ + unsigned long slop = memparse(ptr, NULL); + + xen_timerop_clockevent.min_delta_ns = slop; + xen_timerop_clockevent.min_delta_ticks = slop; + xen_vcpuop_clockevent.min_delta_ns = slop; + xen_vcpuop_clockevent.min_delta_ticks = slop; + + return 0; +} +early_param("xen_timer_slop", parse_xen_timer_slop); -- cgit v1.2.3-58-ga151 From c9f804d64bb93c8dbf957df1d7e9de11380e522d Mon Sep 17 00:00:00 2001 From: Roger Pau Monne Date: Tue, 23 Apr 2019 15:04:15 +0200 Subject: xen/pvh: set xen_domain_type to HVM in xen_pvh_init MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Or else xen_domain() returns false despite xen_pvh being set. Signed-off-by: Roger Pau Monné Reviewed-by: Boris Ostrovsky Signed-off-by: Boris Ostrovsky Cc: stable@vger.kernel.org # 4.19+ --- arch/x86/xen/enlighten_pvh.c | 1 + 1 file changed, 1 insertion(+) (limited to 'arch/x86') diff --git a/arch/x86/xen/enlighten_pvh.c b/arch/x86/xen/enlighten_pvh.c index 35b7599d2d0b..bbffa409e0e8 100644 --- a/arch/x86/xen/enlighten_pvh.c +++ b/arch/x86/xen/enlighten_pvh.c @@ -27,6 +27,7 @@ void __init xen_pvh_init(void) u64 pfn; xen_pvh = 1; + xen_domain_type = XEN_HVM_DOMAIN; xen_start_flags = pvh_start_info.flags; msr = cpuid_ebx(xen_cpuid_base() + 2); -- cgit v1.2.3-58-ga151 From 72813bfbf0276a97c82af038efb5f02dcdd9e310 Mon Sep 17 00:00:00 2001 From: Roger Pau Monne Date: Tue, 23 Apr 2019 15:04:16 +0200 Subject: xen/pvh: correctly setup the PV EFI interface for dom0 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit This involves initializing the boot params EFI related fields and the efi global variable. Without this fix a PVH dom0 doesn't detect when booted from EFI, and thus doesn't support accessing any of the EFI related data. Reported-by: PGNet Dev Signed-off-by: Roger Pau Monné Reviewed-by: Boris Ostrovsky Signed-off-by: Boris Ostrovsky Cc: stable@vger.kernel.org # 4.19+ --- arch/x86/platform/pvh/enlighten.c | 8 ++++---- arch/x86/xen/efi.c | 12 ++++++------ arch/x86/xen/enlighten_pv.c | 2 +- arch/x86/xen/enlighten_pvh.c | 6 +++++- arch/x86/xen/xen-ops.h | 4 ++-- 5 files changed, 18 insertions(+), 14 deletions(-) (limited to 'arch/x86') diff --git a/arch/x86/platform/pvh/enlighten.c b/arch/x86/platform/pvh/enlighten.c index 62f5c7045944..1861a2ba0f2b 100644 --- a/arch/x86/platform/pvh/enlighten.c +++ b/arch/x86/platform/pvh/enlighten.c @@ -44,8 +44,6 @@ void __init __weak mem_map_via_hcall(struct boot_params *ptr __maybe_unused) static void __init init_pvh_bootparams(bool xen_guest) { - memset(&pvh_bootparams, 0, sizeof(pvh_bootparams)); - if ((pvh_start_info.version > 0) && (pvh_start_info.memmap_entries)) { struct hvm_memmap_table_entry *ep; int i; @@ -103,7 +101,7 @@ static void __init init_pvh_bootparams(bool xen_guest) * If we are trying to boot a Xen PVH guest, it is expected that the kernel * will have been configured to provide the required override for this routine. */ -void __init __weak xen_pvh_init(void) +void __init __weak xen_pvh_init(struct boot_params *boot_params) { xen_raw_printk("Error: Missing xen PVH initialization\n"); BUG(); @@ -112,7 +110,7 @@ void __init __weak xen_pvh_init(void) static void hypervisor_specific_init(bool xen_guest) { if (xen_guest) - xen_pvh_init(); + xen_pvh_init(&pvh_bootparams); } /* @@ -131,6 +129,8 @@ void __init xen_prepare_pvh(void) BUG(); } + memset(&pvh_bootparams, 0, sizeof(pvh_bootparams)); + hypervisor_specific_init(xen_guest); init_pvh_bootparams(xen_guest); diff --git a/arch/x86/xen/efi.c b/arch/x86/xen/efi.c index 1fbb629a9d78..0d3365cb64de 100644 --- a/arch/x86/xen/efi.c +++ b/arch/x86/xen/efi.c @@ -158,7 +158,7 @@ static enum efi_secureboot_mode xen_efi_get_secureboot(void) return efi_secureboot_mode_unknown; } -void __init xen_efi_init(void) +void __init xen_efi_init(struct boot_params *boot_params) { efi_system_table_t *efi_systab_xen; @@ -167,12 +167,12 @@ void __init xen_efi_init(void) if (efi_systab_xen == NULL) return; - strncpy((char *)&boot_params.efi_info.efi_loader_signature, "Xen", - sizeof(boot_params.efi_info.efi_loader_signature)); - boot_params.efi_info.efi_systab = (__u32)__pa(efi_systab_xen); - boot_params.efi_info.efi_systab_hi = (__u32)(__pa(efi_systab_xen) >> 32); + strncpy((char *)&boot_params->efi_info.efi_loader_signature, "Xen", + sizeof(boot_params->efi_info.efi_loader_signature)); + boot_params->efi_info.efi_systab = (__u32)__pa(efi_systab_xen); + boot_params->efi_info.efi_systab_hi = (__u32)(__pa(efi_systab_xen) >> 32); - boot_params.secure_boot = xen_efi_get_secureboot(); + boot_params->secure_boot = xen_efi_get_secureboot(); set_bit(EFI_BOOT, &efi.flags); set_bit(EFI_PARAVIRT, &efi.flags); diff --git a/arch/x86/xen/enlighten_pv.c b/arch/x86/xen/enlighten_pv.c index c54a493e139a..4722ba2966ac 100644 --- a/arch/x86/xen/enlighten_pv.c +++ b/arch/x86/xen/enlighten_pv.c @@ -1403,7 +1403,7 @@ asmlinkage __visible void __init xen_start_kernel(void) /* We need this for printk timestamps */ xen_setup_runstate_info(0); - xen_efi_init(); + xen_efi_init(&boot_params); /* Start the world */ #ifdef CONFIG_X86_32 diff --git a/arch/x86/xen/enlighten_pvh.c b/arch/x86/xen/enlighten_pvh.c index bbffa409e0e8..80a79db72fcf 100644 --- a/arch/x86/xen/enlighten_pvh.c +++ b/arch/x86/xen/enlighten_pvh.c @@ -13,6 +13,8 @@ #include +#include "xen-ops.h" + /* * PVH variables. * @@ -21,7 +23,7 @@ */ bool xen_pvh __attribute__((section(".data"))) = 0; -void __init xen_pvh_init(void) +void __init xen_pvh_init(struct boot_params *boot_params) { u32 msr; u64 pfn; @@ -33,6 +35,8 @@ void __init xen_pvh_init(void) msr = cpuid_ebx(xen_cpuid_base() + 2); pfn = __pa(hypercall_page); wrmsr_safe(msr, (u32)pfn, (u32)(pfn >> 32)); + + xen_efi_init(boot_params); } void __init mem_map_via_hcall(struct boot_params *boot_params_p) diff --git a/arch/x86/xen/xen-ops.h b/arch/x86/xen/xen-ops.h index 0e60bd918695..2f111f47ba98 100644 --- a/arch/x86/xen/xen-ops.h +++ b/arch/x86/xen/xen-ops.h @@ -122,9 +122,9 @@ static inline void __init xen_init_vga(const struct dom0_vga_console_info *info, void __init xen_init_apic(void); #ifdef CONFIG_XEN_EFI -extern void xen_efi_init(void); +extern void xen_efi_init(struct boot_params *boot_params); #else -static inline void __init xen_efi_init(void) +static inline void __init xen_efi_init(struct boot_params *boot_params) { } #endif -- cgit v1.2.3-58-ga151