cachepc

commit 0c825583fc20f1b91c56e1aaf450d6a753d24658
parent ca3b348013267bf727ba52bb6fc97a7ab7d367dc
Author: Louis Burda <quent.burda@gmail.com>
Date:   Thu,  2 Feb 2023 18:38:00 -0600

qemu-pagestep is quasi-realtime when suppresing slow kernel logging

Diffstat:
M
Makefile
 | 
2
+-
M
cachepc/cachepc.h
 | 
14
+++++++++++---
M
cachepc/const.h
 | 
3
+++
M
cachepc/kvm.c
 | 
44
++++++++++++++++++++++++++++++++++----------
M
cachepc/uapi.h
 | 
2
+-
M
util/.gitignore
 | 
2
+-
D
util/debug.c
 | 
25
-------------------------
A
util/loglevel.c
 | 
34
++++++++++++++++++++++++++++++++++

8 files changed, 85 insertions(+), 41 deletions(-)
diff --git a/Makefile b/Makefile
@@ -12,7 +12,7 @@ BINS += test/kvm-pagestep test/kvm-pagestep_guest
 BINS += test/qemu-pagestep
 BINS += test/qemu-eviction test/qemu-eviction_guest
 # BINS += test/qemu-aes_guest test/qemu-aes
-BINS += util/debug util/reset util/mainpfn
+BINS += util/loglevel util/reset util/mainpfn
 
 CFLAGS = -I . -I linux/usr/include
 CFLAGS += -g -Wunused-variable -Wunknown-pragmas -Wunused-function
diff --git a/cachepc/cachepc.h b/cachepc/cachepc.h
@@ -12,8 +12,13 @@
 #define PMC_GUEST (1 << 0)
 
 #define CPC_DBG(...) do { \
-	if (cpc_debug) pr_info("CachePC: " __VA_ARGS__); } while (0)
-#define CPC_INFO(...) do { pr_info("CachePC: " __VA_ARGS__); } while (0)
+		if (cpc_loglevel >= CPC_LOGLVL_DBG) \
+			pr_info("CachePC: " __VA_ARGS__); \
+	} while (0)
+#define CPC_INFO(...) do { \
+		if (cpc_loglevel >= CPC_LOGLVL_INFO) \
+			pr_info("CachePC: " __VA_ARGS__); \
+	} while (0)
 #define CPC_WARN(...) do { pr_warn("CachePC: " __VA_ARGS__); } while (0)
 #define CPC_ERR(...) do { pr_err("CachePC: " __VA_ARGS__); } while (0)
 
@@ -83,7 +88,7 @@ uint64_t cpc_read_pmc(uint64_t event);
 
 void cpc_apic_oneshot_run(uint32_t interval);
 
-extern bool cpc_debug;
+extern uint32_t cpc_loglevel;
 
 extern uint8_t *cpc_msrmts;
 extern uint8_t *cpc_baseline;
@@ -102,6 +107,9 @@ extern bool cpc_long_step;
 
 extern bool cpc_apic_oneshot;
 extern int32_t cpc_apic_timer;
+extern uint32_t cpc_apic_timer_min;
+extern uint32_t cpc_apic_timer_dec_npf;
+extern uint32_t cpc_apic_timer_dec_intr;
 
 extern uint32_t cpc_track_mode;
 extern uint64_t cpc_track_start_gfn;
diff --git a/cachepc/const.h b/cachepc/const.h
@@ -28,3 +28,6 @@
 #define CPC_APIC_TIMER_MIN (20 * CPC_APIC_TIMER_SOFTDIV)
 
 #define CPC_EVENT_BATCH_MAX 1000
+
+#define CPC_LOGLVL_INFO 1
+#define CPC_LOGLVL_DBG 2
diff --git a/cachepc/kvm.c b/cachepc/kvm.c
@@ -18,8 +18,8 @@
 
 #define TEST_REPEAT_MAX 1000
 
-bool cpc_debug = false;
-EXPORT_SYMBOL(cpc_debug);
+uint32_t cpc_loglevel = 0;
+EXPORT_SYMBOL(cpc_loglevel);
 
 uint8_t *cpc_msrmts = NULL;
 EXPORT_SYMBOL(cpc_msrmts);
@@ -64,6 +64,13 @@ int32_t cpc_apic_timer = 0;
 EXPORT_SYMBOL(cpc_apic_oneshot);
 EXPORT_SYMBOL(cpc_apic_timer);
 
+uint32_t cpc_apic_timer_min = 0;
+uint32_t cpc_apic_timer_dec_npf = 0;
+uint32_t cpc_apic_timer_dec_intr = 0;
+EXPORT_SYMBOL(cpc_apic_timer_min);
+EXPORT_SYMBOL(cpc_apic_timer_dec_npf);
+EXPORT_SYMBOL(cpc_apic_timer_dec_intr);
+
 uint32_t cpc_track_mode = false;
 uint64_t cpc_track_start_gfn = 0;
 uint64_t cpc_track_end_gfn = 0;
@@ -101,7 +108,7 @@ static void cpc_pmc_setup(void *p);
 static void cpc_system_setup(void);
 
 static int cpc_reset_ioctl(void __user *arg_user);
-static int cpc_debug_ioctl(void __user *arg_user);
+static int cpc_loglevel_ioctl(void __user *arg_user);
 
 static int cpc_memory_encrypt_op_ioctl(void __user *arg_user);
 
@@ -298,16 +305,16 @@ cpc_reset_ioctl(void __user *arg_user)
 }
 
 int
-cpc_debug_ioctl(void __user *arg_user)
+cpc_loglevel_ioctl(void __user *arg_user)
 {
-	uint32_t debug;
+	uint32_t level;
 
 	if (!arg_user) return -EINVAL;
 
-	if (copy_from_user(&debug, arg_user, sizeof(uint32_t)))
+	if (copy_from_user(&level, arg_user, sizeof(uint32_t)))
 		return -EFAULT;
 
-	cpc_debug = debug;
+	cpc_loglevel = level;
 
 	return 0;
 }
@@ -474,6 +481,16 @@ cpc_track_mode_ioctl(void __user *arg_user)
 	cpc_singlestep_reset = false;
 	cpc_long_step = false;
 
+	if (sev_es_guest(vcpu->kvm)) {
+		cpc_apic_timer_min = 200;
+		cpc_apic_timer_dec_npf = 25;
+		cpc_apic_timer_dec_intr = 50;
+	} else {
+		cpc_apic_timer_min = 15;
+		cpc_apic_timer_dec_npf = 5;
+		cpc_apic_timer_dec_intr = 10;
+	}
+
 	switch (cfg.mode) {
 	case CPC_TRACK_FAULT_NO_RUN:
 		cpc_prime_probe = true;
@@ -489,6 +506,9 @@ cpc_track_mode_ioctl(void __user *arg_user)
 		cpc_track_all(vcpu, KVM_PAGE_TRACK_EXEC);
 		break;
 	case CPC_TRACK_STEPS:
+		cpc_apic_timer_min = 7000;
+		cpc_apic_timer_dec_npf = 25;
+		cpc_apic_timer_dec_intr = 50;
 		cpc_track_steps.use_target = cfg.steps.use_target;
 		cpc_track_steps.target_gfn = cfg.steps.target_gfn;
 		cpc_track_steps.with_data = cfg.steps.with_data;
@@ -599,8 +619,8 @@ cpc_kvm_ioctl(struct file *file, unsigned int ioctl, unsigned long arg)
 	switch (ioctl) {
 	case KVM_CPC_RESET:
 		return cpc_reset_ioctl(arg_user);
-	case KVM_CPC_DEBUG:
-		return cpc_debug_ioctl(arg_user);
+	case KVM_CPC_LOGLEVEL:
+		return cpc_loglevel_ioctl(arg_user);
 	case KVM_CPC_MEMORY_ENCRYPT_OP:
 		return cpc_memory_encrypt_op_ioctl(arg_user);
 	case KVM_CPC_TEST_EVICTION:
@@ -678,7 +698,7 @@ cpc_kvm_init(void)
 {
 	int ret;
 
-	cpc_debug = false;
+	cpc_loglevel = 1;
 
 	cpc_ds = NULL;
 	cpc_ds_ul = NULL;
@@ -693,6 +713,10 @@ cpc_kvm_init(void)
 	cpc_apic_oneshot = false;
 	cpc_apic_timer = 0;
 
+	cpc_apic_timer_min = 0;
+	cpc_apic_timer_dec_npf = 0;
+	cpc_apic_timer_dec_intr = 0;
+
 	INIT_LIST_HEAD(&cpc_faults);
 
 	cpc_msrmts = kzalloc(L1_SETS, GFP_KERNEL);
diff --git a/cachepc/uapi.h b/cachepc/uapi.h
@@ -10,7 +10,7 @@
 	asm volatile("vmmcall" : : "a" (action), "b"(type), "c" (val) : "rdx")
 
 #define KVM_CPC_RESET _IOWR(KVMIO, 0x20, __u32)
-#define KVM_CPC_DEBUG _IOW(KVMIO, 0x21, __u32)
+#define KVM_CPC_LOGLEVEL _IOW(KVMIO, 0x21, __u32)
 
 #define KVM_CPC_MEMORY_ENCRYPT_OP _IOWR(KVMIO, 0x22, struct kvm_sev_cmd)
 
diff --git a/util/.gitignore b/util/.gitignore
@@ -1,3 +1,3 @@
-debug
+loglevel
 reset
 mainpfn
diff --git a/util/debug.c b/util/debug.c
@@ -1,25 +0,0 @@
-#include "cachepc/uapi.h"
-
-#include <sys/ioctl.h>
-#include <fcntl.h>
-#include <err.h>
-#include <fcntl.h>
-#include <unistd.h>
-#include <stdint.h>
-#include <stdlib.h>
-
-int
-main(int argc, const char **argv)
-{
-	uint32_t arg;
-	int fd, ret;
-
-	fd = open("/dev/kvm", O_RDONLY);
-	if (fd < 0) err(1, "open");
-
-	arg = argc > 1 ? atoi(argv[1]) : 1;
-	ret = ioctl(fd, KVM_CPC_DEBUG, &arg);
-	if (ret == -1) err(1, "ioctl KVM_CPC_DEBUG");
-
-	close(fd);
-}
diff --git a/util/loglevel.c b/util/loglevel.c
@@ -0,0 +1,34 @@
+#include "cachepc/uapi.h"
+
+#include <sys/ioctl.h>
+#include <fcntl.h>
+#include <err.h>
+#include <fcntl.h>
+#include <unistd.h>
+#include <string.h>
+#include <stdio.h>
+#include <stdint.h>
+#include <stdlib.h>
+
+int
+main(int argc, const char **argv)
+{
+	uint32_t arg;
+	int fd, ret;
+
+	fd = open("/dev/kvm", O_RDONLY);
+	if (fd < 0) err(1, "open");
+
+	if (argc > 1 && !strcmp(argv[1], "debug"))
+		arg = CPC_LOGLVL_DBG;
+	else if (argc > 1 && !strcmp(argv[1], "info"))
+		arg = CPC_LOGLVL_INFO;
+	else
+		arg = 0;
+
+	printf("loglevel: %i\n", arg);
+	ret = ioctl(fd, KVM_CPC_LOGLEVEL, &arg);
+	if (ret == -1) err(1, "ioctl KVM_CPC_LOGLEVEL");
+
+	close(fd);
+}