* kvm-unit-tests: add tscdeadline-latency test
@ 2014-12-10 20:23 Marcelo Tosatti
2014-12-10 21:49 ` Paolo Bonzini
0 siblings, 1 reply; 4+ messages in thread
From: Marcelo Tosatti @ 2014-12-10 20:23 UTC (permalink / raw)
To: kvm-devel; +Cc: Paolo Bonzini
To test latency between TSC deadline timer
interrupt injection.
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Index: kvm-unit-tests/config/config-x86-common.mak
===================================================================
--- kvm-unit-tests.orig/config/config-x86-common.mak 2014-06-27 13:43:43.694257143 -0300
+++ kvm-unit-tests/config/config-x86-common.mak 2014-12-10 16:10:41.715339378 -0200
@@ -69,6 +69,8 @@
$(TEST_DIR)/apic.elf: $(cstart.o) $(TEST_DIR)/apic.o
+$(TEST_DIR)/tscdeadline-latency.elf: $(cstart.o) $(TEST_DIR)/tscdeadline-latency.o
+
$(TEST_DIR)/init.elf: $(cstart.o) $(TEST_DIR)/init.o
$(TEST_DIR)/realmode.elf: $(TEST_DIR)/realmode.o
Index: kvm-unit-tests/config/config-x86_64.mak
===================================================================
--- kvm-unit-tests.orig/config/config-x86_64.mak 2014-12-10 16:03:20.609681443 -0200
+++ kvm-unit-tests/config/config-x86_64.mak 2014-12-10 16:10:25.172352577 -0200
@@ -9,5 +9,6 @@
$(TEST_DIR)/pcid.flat $(TEST_DIR)/debug.flat
tests += $(TEST_DIR)/svm.flat
tests += $(TEST_DIR)/vmx.flat
+tests += $(TEST_DIR)/tscdeadline-latency.flat
include config/config-x86-common.mak
Index: kvm-unit-tests/x86/tscdeadline-latency.c
===================================================================
--- /dev/null 1970-01-01 00:00:00.000000000 +0000
+++ kvm-unit-tests/x86/tscdeadline-latency.c 2014-12-10 18:21:38.151253344 -0200
@@ -0,0 +1,110 @@
+/*
+ * qemu command line | grep latency | cut -f 2 -d ":" > latency
+ *
+ * In octave:
+ * load latency
+ * min(list)
+ * max(list)
+ * mean(list)
+ * hist(latency, 50)
+ */
+
+#include "libcflat.h"
+#include "apic.h"
+#include "vm.h"
+#include "smp.h"
+#include "desc.h"
+#include "isr.h"
+#include "msr.h"
+
+static void test_lapic_existence(void)
+{
+ u32 lvr;
+
+ lvr = apic_read(APIC_LVR);
+ printf("apic version: %x\n", lvr);
+ report("apic existence", (u16)lvr == 0x14);
+}
+
+#define TSC_DEADLINE_TIMER_MODE (2 << 17)
+#define TSC_DEADLINE_TIMER_VECTOR 0xef
+#define MSR_IA32_TSC 0x00000010
+#define MSR_IA32_TSCDEADLINE 0x000006e0
+
+static int tdt_count;
+u64 exptime;
+int delta;
+#define TABLE_SIZE 10000
+u64 table[TABLE_SIZE];
+volatile int table_idx;
+
+static void tsc_deadline_timer_isr(isr_regs_t *regs)
+{
+ u64 now = rdtsc();
+ ++tdt_count;
+
+ if (table_idx < TABLE_SIZE && tdt_count > 1)
+ table[table_idx++] = now - exptime;
+
+ exptime = now+delta;
+ wrmsr(MSR_IA32_TSCDEADLINE, now+delta);
+ apic_write(APIC_EOI, 0);
+}
+
+static void start_tsc_deadline_timer(void)
+{
+ handle_irq(TSC_DEADLINE_TIMER_VECTOR, tsc_deadline_timer_isr);
+ irq_enable();
+
+ wrmsr(MSR_IA32_TSCDEADLINE, rdmsr(MSR_IA32_TSC)+delta);
+ asm volatile ("nop");
+}
+
+static int enable_tsc_deadline_timer(void)
+{
+ uint32_t lvtt;
+
+ if (cpuid(1).c & (1 << 24)) {
+ lvtt = TSC_DEADLINE_TIMER_MODE | TSC_DEADLINE_TIMER_VECTOR;
+ apic_write(APIC_LVTT, lvtt);
+ start_tsc_deadline_timer();
+ return 1;
+ } else {
+ return 0;
+ }
+}
+
+static void test_tsc_deadline_timer(void)
+{
+ if(enable_tsc_deadline_timer()) {
+ printf("tsc deadline timer enabled\n");
+ } else {
+ printf("tsc deadline timer not detected\n");
+ }
+}
+
+int main()
+{
+ int i;
+
+ setup_vm();
+ smp_init();
+ setup_idt();
+
+ test_lapic_existence();
+
+ mask_pic_interrupts();
+
+ delta = 200000;
+ test_tsc_deadline_timer();
+ irq_enable();
+
+ do {
+ asm volatile("hlt");
+ } while (table_idx < TABLE_SIZE);
+
+ for (i = 0; i < TABLE_SIZE; i++)
+ printf("latency: %d\n", table[i]);
+
+ return report_summary();
+}
Index: kvm-unit-tests/x86/unittests.cfg
===================================================================
--- kvm-unit-tests.orig/x86/unittests.cfg 2014-12-10 16:03:20.616681437 -0200
+++ kvm-unit-tests/x86/unittests.cfg 2014-12-10 16:15:23.145114609 -0200
@@ -161,3 +161,8 @@
[debug]
file = debug.flat
arch = x86_64
+
+[tscdeadline_latency]
+file = tscdeadline_latency.flat
+extra_params = -cpu qemu64,+tsc-deadline
+arch = x86_64
^ permalink raw reply [flat|nested] 4+ messages in thread* Re: kvm-unit-tests: add tscdeadline-latency test 2014-12-10 20:23 kvm-unit-tests: add tscdeadline-latency test Marcelo Tosatti @ 2014-12-10 21:49 ` Paolo Bonzini 2014-12-11 3:13 ` Marcelo Tosatti 0 siblings, 1 reply; 4+ messages in thread From: Paolo Bonzini @ 2014-12-10 21:49 UTC (permalink / raw) To: Marcelo Tosatti, kvm-devel [-- Attachment #1: Type: text/plain, Size: 6006 bytes --] On 10/12/2014 21:23, Marcelo Tosatti wrote: > > To test latency between TSC deadline timer > interrupt injection. > > Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com> > > Index: kvm-unit-tests/config/config-x86-common.mak > =================================================================== > --- kvm-unit-tests.orig/config/config-x86-common.mak 2014-06-27 13:43:43.694257143 -0300 > +++ kvm-unit-tests/config/config-x86-common.mak 2014-12-10 16:10:41.715339378 -0200 > @@ -69,6 +69,8 @@ > > $(TEST_DIR)/apic.elf: $(cstart.o) $(TEST_DIR)/apic.o > > +$(TEST_DIR)/tscdeadline-latency.elf: $(cstart.o) $(TEST_DIR)/tscdeadline-latency.o > + > $(TEST_DIR)/init.elf: $(cstart.o) $(TEST_DIR)/init.o > > $(TEST_DIR)/realmode.elf: $(TEST_DIR)/realmode.o > Index: kvm-unit-tests/config/config-x86_64.mak > =================================================================== > --- kvm-unit-tests.orig/config/config-x86_64.mak 2014-12-10 16:03:20.609681443 -0200 > +++ kvm-unit-tests/config/config-x86_64.mak 2014-12-10 16:10:25.172352577 -0200 > @@ -9,5 +9,6 @@ > $(TEST_DIR)/pcid.flat $(TEST_DIR)/debug.flat > tests += $(TEST_DIR)/svm.flat > tests += $(TEST_DIR)/vmx.flat > +tests += $(TEST_DIR)/tscdeadline-latency.flat > > include config/config-x86-common.mak > Index: kvm-unit-tests/x86/tscdeadline-latency.c > =================================================================== > --- /dev/null 1970-01-01 00:00:00.000000000 +0000 > +++ kvm-unit-tests/x86/tscdeadline-latency.c 2014-12-10 18:21:38.151253344 -0200 > @@ -0,0 +1,110 @@ > +/* > + * qemu command line | grep latency | cut -f 2 -d ":" > latency > + * > + * In octave: > + * load latency > + * min(list) > + * max(list) > + * mean(list) > + * hist(latency, 50) > + */ > + > +#include "libcflat.h" > +#include "apic.h" > +#include "vm.h" > +#include "smp.h" > +#include "desc.h" > +#include "isr.h" > +#include "msr.h" > + > +static void test_lapic_existence(void) > +{ > + u32 lvr; > + > + lvr = apic_read(APIC_LVR); > + printf("apic version: %x\n", lvr); > + report("apic existence", (u16)lvr == 0x14); > +} > + > +#define TSC_DEADLINE_TIMER_MODE (2 << 17) > +#define TSC_DEADLINE_TIMER_VECTOR 0xef > +#define MSR_IA32_TSC 0x00000010 > +#define MSR_IA32_TSCDEADLINE 0x000006e0 > + > +static int tdt_count; > +u64 exptime; > +int delta; > +#define TABLE_SIZE 10000 > +u64 table[TABLE_SIZE]; > +volatile int table_idx; > + > +static void tsc_deadline_timer_isr(isr_regs_t *regs) > +{ > + u64 now = rdtsc(); > + ++tdt_count; > + > + if (table_idx < TABLE_SIZE && tdt_count > 1) > + table[table_idx++] = now - exptime; > + > + exptime = now+delta; > + wrmsr(MSR_IA32_TSCDEADLINE, now+delta); > + apic_write(APIC_EOI, 0); > +} > + > +static void start_tsc_deadline_timer(void) > +{ > + handle_irq(TSC_DEADLINE_TIMER_VECTOR, tsc_deadline_timer_isr); > + irq_enable(); > + > + wrmsr(MSR_IA32_TSCDEADLINE, rdmsr(MSR_IA32_TSC)+delta); > + asm volatile ("nop"); > +} > + > +static int enable_tsc_deadline_timer(void) > +{ > + uint32_t lvtt; > + > + if (cpuid(1).c & (1 << 24)) { > + lvtt = TSC_DEADLINE_TIMER_MODE | TSC_DEADLINE_TIMER_VECTOR; > + apic_write(APIC_LVTT, lvtt); > + start_tsc_deadline_timer(); > + return 1; > + } else { > + return 0; > + } > +} > + > +static void test_tsc_deadline_timer(void) > +{ > + if(enable_tsc_deadline_timer()) { > + printf("tsc deadline timer enabled\n"); > + } else { > + printf("tsc deadline timer not detected\n"); > + } > +} > + > +int main() > +{ > + int i; > + > + setup_vm(); > + smp_init(); > + setup_idt(); > + > + test_lapic_existence(); > + > + mask_pic_interrupts(); > + > + delta = 200000; > + test_tsc_deadline_timer(); > + irq_enable(); > + > + do { > + asm volatile("hlt"); > + } while (table_idx < TABLE_SIZE); > + > + for (i = 0; i < TABLE_SIZE; i++) > + printf("latency: %d\n", table[i]); > + > + return report_summary(); > +} > Index: kvm-unit-tests/x86/unittests.cfg > =================================================================== > --- kvm-unit-tests.orig/x86/unittests.cfg 2014-12-10 16:03:20.616681437 -0200 > +++ kvm-unit-tests/x86/unittests.cfg 2014-12-10 16:15:23.145114609 -0200 > @@ -161,3 +161,8 @@ > [debug] > file = debug.flat > arch = x86_64 > + > +[tscdeadline_latency] > +file = tscdeadline_latency.flat > +extra_params = -cpu qemu64,+tsc-deadline > +arch = x86_64 > -- > To unsubscribe from this list: send the line "unsubscribe kvm" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html > Applied, thanks. Here is a script I use to run it: #! /bin/sh time ./x86/run x86/tscdeadline-latency.flat -cpu host | sed -n 's/^latency: //p' > l.txt time ./x86/run x86/tscdeadline-latency.flat -append '2000000 4000' -cpu host | sed -n 's/^latency: //p' > l2.txt time ./x86/run x86/tscdeadline-latency.flat -append '4000000 2000' -cpu host | sed -n 's/^latency: //p' > l3.txt gnuplot << \EOF hist(x,width)=width*floor(x/width) + binwidth/2.0 binwidth=500 set xrange [0:50000] set boxwidth binwidth set term png size 1024,512 set output "200000,10000.png" plot 'l.txt' using (hist($1,binwidth)):(1.0/10000) smooth freq with boxes binwidth=3000 set xrange [0:500000] set boxwidth binwidth set term png size 1024,512 set output "2000000,4000.png" plot 'l2.txt' using (hist($1,binwidth)):(1.0/4000) smooth freq with boxes binwidth=3000 set xrange [0:500000] set boxwidth binwidth set term png size 1024,512 set output "4000000,2000.png" plot 'l3.txt' using (hist($1,binwidth)):(1.0/2000) smooth freq with boxes EOF and I attach the plots I get with a non-realtime kernel. I'll try a realtime kernel tomorrow; in the meanwhile, can you attach the three plots you get on your machine too (RT), so that we can be sure we're looking at the same thing? Paolo [-- Attachment #2: 200000,10000.png --] [-- Type: image/png, Size: 5727 bytes --] [-- Attachment #3: 2000000,4000.png --] [-- Type: image/png, Size: 5324 bytes --] [-- Attachment #4: 4000000,2000.png --] [-- Type: image/png, Size: 6429 bytes --] ^ permalink raw reply [flat|nested] 4+ messages in thread
* Re: kvm-unit-tests: add tscdeadline-latency test 2014-12-10 21:49 ` Paolo Bonzini @ 2014-12-11 3:13 ` Marcelo Tosatti 2014-12-11 18:39 ` Paolo Bonzini 0 siblings, 1 reply; 4+ messages in thread From: Marcelo Tosatti @ 2014-12-11 3:13 UTC (permalink / raw) To: Paolo Bonzini; +Cc: kvm-devel [-- Attachment #1: Type: text/plain, Size: 6511 bytes --] On Wed, Dec 10, 2014 at 10:49:52PM +0100, Paolo Bonzini wrote: > > > On 10/12/2014 21:23, Marcelo Tosatti wrote: > > > > To test latency between TSC deadline timer > > interrupt injection. > > > > Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com> > > > > Index: kvm-unit-tests/config/config-x86-common.mak > > =================================================================== > > --- kvm-unit-tests.orig/config/config-x86-common.mak 2014-06-27 13:43:43.694257143 -0300 > > +++ kvm-unit-tests/config/config-x86-common.mak 2014-12-10 16:10:41.715339378 -0200 > > @@ -69,6 +69,8 @@ > > > > $(TEST_DIR)/apic.elf: $(cstart.o) $(TEST_DIR)/apic.o > > > > +$(TEST_DIR)/tscdeadline-latency.elf: $(cstart.o) $(TEST_DIR)/tscdeadline-latency.o > > + > > $(TEST_DIR)/init.elf: $(cstart.o) $(TEST_DIR)/init.o > > > > $(TEST_DIR)/realmode.elf: $(TEST_DIR)/realmode.o > > Index: kvm-unit-tests/config/config-x86_64.mak > > =================================================================== > > --- kvm-unit-tests.orig/config/config-x86_64.mak 2014-12-10 16:03:20.609681443 -0200 > > +++ kvm-unit-tests/config/config-x86_64.mak 2014-12-10 16:10:25.172352577 -0200 > > @@ -9,5 +9,6 @@ > > $(TEST_DIR)/pcid.flat $(TEST_DIR)/debug.flat > > tests += $(TEST_DIR)/svm.flat > > tests += $(TEST_DIR)/vmx.flat > > +tests += $(TEST_DIR)/tscdeadline-latency.flat > > > > include config/config-x86-common.mak > > Index: kvm-unit-tests/x86/tscdeadline-latency.c > > =================================================================== > > --- /dev/null 1970-01-01 00:00:00.000000000 +0000 > > +++ kvm-unit-tests/x86/tscdeadline-latency.c 2014-12-10 18:21:38.151253344 -0200 > > @@ -0,0 +1,110 @@ > > +/* > > + * qemu command line | grep latency | cut -f 2 -d ":" > latency > > + * > > + * In octave: > > + * load latency > > + * min(list) > > + * max(list) > > + * mean(list) > > + * hist(latency, 50) > > + */ > > + > > +#include "libcflat.h" > > +#include "apic.h" > > +#include "vm.h" > > +#include "smp.h" > > +#include "desc.h" > > +#include "isr.h" > > +#include "msr.h" > > + > > +static void test_lapic_existence(void) > > +{ > > + u32 lvr; > > + > > + lvr = apic_read(APIC_LVR); > > + printf("apic version: %x\n", lvr); > > + report("apic existence", (u16)lvr == 0x14); > > +} > > + > > +#define TSC_DEADLINE_TIMER_MODE (2 << 17) > > +#define TSC_DEADLINE_TIMER_VECTOR 0xef > > +#define MSR_IA32_TSC 0x00000010 > > +#define MSR_IA32_TSCDEADLINE 0x000006e0 > > + > > +static int tdt_count; > > +u64 exptime; > > +int delta; > > +#define TABLE_SIZE 10000 > > +u64 table[TABLE_SIZE]; > > +volatile int table_idx; > > + > > +static void tsc_deadline_timer_isr(isr_regs_t *regs) > > +{ > > + u64 now = rdtsc(); > > + ++tdt_count; > > + > > + if (table_idx < TABLE_SIZE && tdt_count > 1) > > + table[table_idx++] = now - exptime; > > + > > + exptime = now+delta; > > + wrmsr(MSR_IA32_TSCDEADLINE, now+delta); > > + apic_write(APIC_EOI, 0); > > +} > > + > > +static void start_tsc_deadline_timer(void) > > +{ > > + handle_irq(TSC_DEADLINE_TIMER_VECTOR, tsc_deadline_timer_isr); > > + irq_enable(); > > + > > + wrmsr(MSR_IA32_TSCDEADLINE, rdmsr(MSR_IA32_TSC)+delta); > > + asm volatile ("nop"); > > +} > > + > > +static int enable_tsc_deadline_timer(void) > > +{ > > + uint32_t lvtt; > > + > > + if (cpuid(1).c & (1 << 24)) { > > + lvtt = TSC_DEADLINE_TIMER_MODE | TSC_DEADLINE_TIMER_VECTOR; > > + apic_write(APIC_LVTT, lvtt); > > + start_tsc_deadline_timer(); > > + return 1; > > + } else { > > + return 0; > > + } > > +} > > + > > +static void test_tsc_deadline_timer(void) > > +{ > > + if(enable_tsc_deadline_timer()) { > > + printf("tsc deadline timer enabled\n"); > > + } else { > > + printf("tsc deadline timer not detected\n"); > > + } > > +} > > + > > +int main() > > +{ > > + int i; > > + > > + setup_vm(); > > + smp_init(); > > + setup_idt(); > > + > > + test_lapic_existence(); > > + > > + mask_pic_interrupts(); > > + > > + delta = 200000; > > + test_tsc_deadline_timer(); > > + irq_enable(); > > + > > + do { > > + asm volatile("hlt"); > > + } while (table_idx < TABLE_SIZE); > > + > > + for (i = 0; i < TABLE_SIZE; i++) > > + printf("latency: %d\n", table[i]); > > + > > + return report_summary(); > > +} > > Index: kvm-unit-tests/x86/unittests.cfg > > =================================================================== > > --- kvm-unit-tests.orig/x86/unittests.cfg 2014-12-10 16:03:20.616681437 -0200 > > +++ kvm-unit-tests/x86/unittests.cfg 2014-12-10 16:15:23.145114609 -0200 > > @@ -161,3 +161,8 @@ > > [debug] > > file = debug.flat > > arch = x86_64 > > + > > +[tscdeadline_latency] > > +file = tscdeadline_latency.flat > > +extra_params = -cpu qemu64,+tsc-deadline > > +arch = x86_64 > > -- > > To unsubscribe from this list: send the line "unsubscribe kvm" in > > the body of a message to majordomo@vger.kernel.org > > More majordomo info at http://vger.kernel.org/majordomo-info.html > > > > Applied, thanks. Here is a script I use to run it: > > #! /bin/sh > time ./x86/run x86/tscdeadline-latency.flat -cpu host | sed -n 's/^latency: //p' > l.txt > time ./x86/run x86/tscdeadline-latency.flat -append '2000000 4000' -cpu host | sed -n 's/^latency: //p' > l2.txt > time ./x86/run x86/tscdeadline-latency.flat -append '4000000 2000' -cpu host | sed -n 's/^latency: //p' > l3.txt > > gnuplot << \EOF > hist(x,width)=width*floor(x/width) + binwidth/2.0 > > binwidth=500 > set xrange [0:50000] > set boxwidth binwidth > set term png size 1024,512 > set output "200000,10000.png" > plot 'l.txt' using (hist($1,binwidth)):(1.0/10000) smooth freq with boxes > > binwidth=3000 > set xrange [0:500000] > set boxwidth binwidth > set term png size 1024,512 > set output "2000000,4000.png" > plot 'l2.txt' using (hist($1,binwidth)):(1.0/4000) smooth freq with boxes > > binwidth=3000 > set xrange [0:500000] > set boxwidth binwidth > set term png size 1024,512 > set output "4000000,2000.png" > plot 'l3.txt' using (hist($1,binwidth)):(1.0/2000) smooth freq with boxes > EOF > > and I attach the plots I get with a non-realtime kernel. I'll try a > realtime kernel tomorrow; in the meanwhile, can you attach the three > plots you get on your machine too (RT), so that we can be sure we're > looking at the same thing? > > Paolo Attached. 3.10.0-rt kernel. [-- Attachment #2: 2000000,4000.png --] [-- Type: image/png, Size: 4156 bytes --] [-- Attachment #3: 200000,10000.png --] [-- Type: image/png, Size: 5519 bytes --] [-- Attachment #4: 4000000,2000.png --] [-- Type: image/png, Size: 4247 bytes --] ^ permalink raw reply [flat|nested] 4+ messages in thread
* Re: kvm-unit-tests: add tscdeadline-latency test 2014-12-11 3:13 ` Marcelo Tosatti @ 2014-12-11 18:39 ` Paolo Bonzini 0 siblings, 0 replies; 4+ messages in thread From: Paolo Bonzini @ 2014-12-11 18:39 UTC (permalink / raw) To: Marcelo Tosatti; +Cc: kvm-devel On 11/12/2014 04:13, Marcelo Tosatti wrote: > Attached. > > 3.10.0-rt kernel. Whoa, that's great. Please make a v4 of the KVM patches, that documents the difference between checking IRR and ISR, and has the other small changes. Then I guess we're good to go. Paolo ^ permalink raw reply [flat|nested] 4+ messages in thread
end of thread, other threads:[~2014-12-11 18:39 UTC | newest] Thread overview: 4+ messages (download: mbox.gz follow: Atom feed -- links below jump to the message on this page -- 2014-12-10 20:23 kvm-unit-tests: add tscdeadline-latency test Marcelo Tosatti 2014-12-10 21:49 ` Paolo Bonzini 2014-12-11 3:13 ` Marcelo Tosatti 2014-12-11 18:39 ` Paolo Bonzini
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