drm/vmwgfx: Introduce VMware mks-guest-stats

VMware mks-guest-stats mechanism allows the collection of performance stats from
guest userland GL contexts, as well as from vmwgfx kernelspace, via a set of sw-
defined performance counters. The userspace performance counters are (de)registerd
with vmware-vmx-stats hypervisor via new iocts. The vmwgfx kernelspace counters
are controlled at build-time via a new config DRM_VMWGFX_MKSSTATS.

* Add vmw_mksstat_{add|remove|reset}_ioctl controlling the tracking of
  mks-guest-stats in guest winsys contexts
* Add DRM_VMWGFX_MKSSTATS config to drivers/gpu/drm/vmwgfx/Kconfig controlling
  the instrumentation of vmwgfx for kernelspace mks-guest-stats counters
* Instrument vmwgfx vmw_execbuf_ioctl to collect mks-guest-stats according to
  DRM_VMWGFX_MKSSTATS
Signed-off-by: Martin Krastev <krastevm@vmware.com>
Reviewed-by: Zack Rusin <zackr@vmware.com>
Signed-off-by: Zack Rusin <zackr@vmware.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210609172307.131929-3-zackr@vmware.com

drivers/gpu/drm/vmwgfx/Kconfig

@@ -22,3 +22,10 @@ config DRM_VMWGFX_FBCON
 	   Choose this option if you are shipping a new vmwgfx
 	   userspace driver that supports using the kernel driver.
 
+config DRM_VMWGFX_MKSSTATS
+	bool "Enable mksGuestStats instrumentation of vmwgfx by default"
+	depends on DRM_VMWGFX
+	default n
+	help
+	   Choose this option to instrument the kernel driver for mksGuestStats.
+

drivers/gpu/drm/vmwgfx/device_include/svga_types.h

@@ -23,9 +23,11 @@
  * SOFTWARE.
  *
  **********************************************************/
-#ifndef _VM_BASIC_TYPES_H_
-#define _VM_BASIC_TYPES_H_
+#ifndef _SVGA_TYPES_H_
+#define _SVGA_TYPES_H_
 #include <linux/kernel.h>
+#include <linux/mm.h>
+#include <asm/page.h>
 
 typedef u32 uint32;
 typedef s32 int32;
@@ -48,4 +50,90 @@ typedef bool Bool;
 
 #define CONST64U(x) x##ULL
 
+/*
+ * MKS Guest Stats types
+ */
+
+typedef struct MKSGuestStatCounter {
+	atomic64_t count;
+} MKSGuestStatCounter;
+
+typedef struct MKSGuestStatCounterTime {
+	MKSGuestStatCounter counter;
+	atomic64_t selfCycles;
+	atomic64_t totalCycles;
+} MKSGuestStatCounterTime;
+
+/*
+ * Flags for MKSGuestStatInfoEntry::flags below
+ */
+
+#define MKS_GUEST_STAT_FLAG_NONE    0
+#define MKS_GUEST_STAT_FLAG_TIME    (1U << 0)
+
+typedef __attribute__((aligned(32))) struct MKSGuestStatInfoEntry {
+	union {
+		const char *s;
+		uint64 u;
+	} name;
+	union {
+		const char *s;
+		uint64 u;
+	} description;
+	uint64 flags;
+	union {
+		MKSGuestStatCounter *counter;
+		MKSGuestStatCounterTime *counterTime;
+		uint64 u;
+	} stat;
+} MKSGuestStatInfoEntry;
+
+#define INVALID_PPN64       ((PPN64)0x000fffffffffffffULL)
+#define vmw_num_pages(size) (PAGE_ALIGN(size) >> PAGE_SHIFT)
+
+#define MKS_GUEST_STAT_INSTANCE_DESC_LENGTH 1024
+#define MKS_GUEST_STAT_INSTANCE_MAX_STATS   4096
+#define MKS_GUEST_STAT_INSTANCE_MAX_STAT_PPNS                \
+	(vmw_num_pages(MKS_GUEST_STAT_INSTANCE_MAX_STATS *   \
+		sizeof(MKSGuestStatCounterTime)))
+#define MKS_GUEST_STAT_INSTANCE_MAX_INFO_PPNS                \
+	(vmw_num_pages(MKS_GUEST_STAT_INSTANCE_MAX_STATS *   \
+		sizeof(MKSGuestStatInfoEntry)))
+#define MKS_GUEST_STAT_AVERAGE_NAME_LENGTH  40
+#define MKS_GUEST_STAT_INSTANCE_MAX_STRS_PPNS                \
+	(vmw_num_pages(MKS_GUEST_STAT_INSTANCE_MAX_STATS *   \
+		MKS_GUEST_STAT_AVERAGE_NAME_LENGTH))
+
+/*
+ * The MKSGuestStatInstanceDescriptor is used as main interface to
+ * communicate guest stats back to the host code.  The guest must
+ * allocate an instance of this structure at the start of a page and
+ * provide the physical address to the host.  From there the host code
+ * can walk this structure to find other (pinned) pages containing the
+ * stats data.
+ *
+ * Since the MKSGuestStatInfoEntry structures contain userlevel
+ * pointers, the InstanceDescriptor also contains pointers to the
+ * begining of these sections allowing the host side code to correctly
+ * interpret the pointers.
+ *
+ * Because the host side code never acknowledges anything back to the
+ * guest there is no strict requirement to maintain compatability
+ * across releases.  If the interface changes the host might not be
+ * able to log stats, but the guest will continue to run normally.
+ */
+
+typedef struct MKSGuestStatInstanceDescriptor {
+	uint64 reservedMBZ; /* must be zero for now. */
+	uint64 statStartVA; /* VA of the start of the stats section. */
+	uint64 strsStartVA; /* VA of the start of the strings section. */
+	uint64 statLength;  /* length of the stats section in bytes. */
+	uint64 infoLength;  /* length of the info entry section in bytes. */
+	uint64 strsLength;  /* length of the strings section in bytes. */
+	PPN64  statPPNs[MKS_GUEST_STAT_INSTANCE_MAX_STAT_PPNS]; /* stat counters */
+	PPN64  infoPPNs[MKS_GUEST_STAT_INSTANCE_MAX_INFO_PPNS]; /* stat info */
+	PPN64  strsPPNs[MKS_GUEST_STAT_INSTANCE_MAX_STRS_PPNS]; /* strings */
+	char   description[MKS_GUEST_STAT_INSTANCE_DESC_LENGTH];
+} MKSGuestStatInstanceDescriptor;
+
 #endif

drivers/gpu/drm/vmwgfx/device_include/vm_basic_types.h

-/* SPDX-License-Identifier: GPL-2.0 */
-#ifndef _VM_BASIC_TYPES_H_
-#define _VM_BASIC_TYPES_H_
-#include <linux/kernel.h>
-
-typedef u32 uint32;
-typedef s32 int32;
-typedef u64 uint64;
-typedef u16 uint16;
-typedef s16 int16;
-typedef u8  uint8;
-typedef s8  int8;
-
-typedef uint64 PA;
-typedef uint32 PPN;
-typedef uint64 PPN64;
-
-typedef bool Bool;
-
-#define MAX_UINT32 U32_MAX
-
-#endif

drivers/gpu/drm/vmwgfx/vmwgfx_drv.c

@@ -43,6 +43,7 @@
 #include "vmwgfx_binding.h"
 #include "vmwgfx_devcaps.h"
 #include "vmwgfx_drv.h"
+#include "vmwgfx_mksstat.h"
 
 #define VMWGFX_DRIVER_DESC "Linux drm driver for VMware graphics devices"
 
@@ -148,6 +149,14 @@
 #define DRM_IOCTL_VMW_MSG						\
 	DRM_IOWR(DRM_COMMAND_BASE + DRM_VMW_MSG,			\
 		struct drm_vmw_msg_arg)
+#define DRM_IOCTL_VMW_MKSSTAT_RESET				\
+	DRM_IO(DRM_COMMAND_BASE + DRM_VMW_MKSSTAT_RESET)
+#define DRM_IOCTL_VMW_MKSSTAT_ADD				\
+	DRM_IOWR(DRM_COMMAND_BASE + DRM_VMW_MKSSTAT_ADD,	\
+		struct drm_vmw_mksstat_add_arg)
+#define DRM_IOCTL_VMW_MKSSTAT_REMOVE				\
+	DRM_IOW(DRM_COMMAND_BASE + DRM_VMW_MKSSTAT_REMOVE,	\
+		struct drm_vmw_mksstat_remove_arg)
 
 /*
  * The core DRM version of this macro doesn't account for
@@ -244,6 +253,15 @@ static const struct drm_ioctl_desc vmw_ioctls[] = {
 	VMW_IOCTL_DEF(VMW_MSG,
 		      vmw_msg_ioctl,
 		      DRM_RENDER_ALLOW),
+	VMW_IOCTL_DEF(VMW_MKSSTAT_RESET,
+		      vmw_mksstat_reset_ioctl,
+		      DRM_RENDER_ALLOW),
+	VMW_IOCTL_DEF(VMW_MKSSTAT_ADD,
+		      vmw_mksstat_add_ioctl,
+		      DRM_RENDER_ALLOW),
+	VMW_IOCTL_DEF(VMW_MKSSTAT_REMOVE,
+		      vmw_mksstat_remove_ioctl,
+		      DRM_RENDER_ALLOW),
 };
 
 static const struct pci_device_id vmw_pci_id_list[] = {
@@ -1137,6 +1155,8 @@ static void vmw_driver_unload(struct drm_device *dev)
 	for (i = vmw_res_context; i < vmw_res_max; ++i)
 		idr_destroy(&dev_priv->res_idr[i]);
 
+	vmw_mksstat_remove_all(dev_priv);
+
 	pci_release_regions(pdev);
 }
 

drivers/gpu/drm/vmwgfx/vmwgfx_drv.h

 /* SPDX-License-Identifier: GPL-2.0 OR MIT */
 /**************************************************************************
  *
- * Copyright 2009-2015 VMware, Inc., Palo Alto, CA., USA
+ * Copyright 2009-2021 VMware, Inc., Palo Alto, CA., USA
  *
  * Permission is hereby granted, free of charge, to any person obtaining a
  * copy of this software and associated documentation files (the
@@ -91,6 +91,9 @@
 #define VMW_RES_FENCE ttm_driver_type3
 #define VMW_RES_SHADER ttm_driver_type4
 
+#define MKSSTAT_CAPACITY_LOG2 5U
+#define MKSSTAT_CAPACITY (1U << MKSSTAT_CAPACITY_LOG2)
+
 struct vmw_fpriv {
 	struct ttm_object_file *tfile;
 	bool gb_aware; /* user-space is guest-backed aware */
@@ -630,6 +633,18 @@ struct vmw_private {
 	struct vmw_validation_mem vvm;
 
 	uint32 *devcaps;
+
+	/*
+	 * mksGuestStat instance-descriptor and pid arrays
+	 */
+	struct page *mksstat_user_pages[MKSSTAT_CAPACITY];
+	atomic_t mksstat_user_pids[MKSSTAT_CAPACITY];
+
+#if IS_ENABLED(CONFIG_DRM_VMWGFX_MKSSTATS)
+	struct page *mksstat_kern_pages[MKSSTAT_CAPACITY];
+	u8 mksstat_kern_top_timer[MKSSTAT_CAPACITY];
+	atomic_t mksstat_kern_pids[MKSSTAT_CAPACITY];
+#endif
 };
 
 static inline struct vmw_surface *vmw_res_to_srf(struct vmw_resource *res)
@@ -1503,6 +1518,17 @@ __printf(1, 2) int vmw_host_printf(const char *fmt, ...);
 int vmw_msg_ioctl(struct drm_device *dev, void *data,
 		  struct drm_file *file_priv);
 
+/* Host mksGuestStats -vmwgfx_msg.c: */
+int vmw_mksstat_get_kern_slot(pid_t pid, struct vmw_private *dev_priv);
+
+int vmw_mksstat_reset_ioctl(struct drm_device *dev, void *data,
+		      struct drm_file *file_priv);
+int vmw_mksstat_add_ioctl(struct drm_device *dev, void *data,
+		      struct drm_file *file_priv);
+int vmw_mksstat_remove_ioctl(struct drm_device *dev, void *data,
+		      struct drm_file *file_priv);
+int vmw_mksstat_remove_all(struct vmw_private *dev_priv);
+
 /* VMW logging */
 
 /**

drivers/gpu/drm/vmwgfx/vmwgfx_execbuf.c

@@ -32,6 +32,7 @@
 #include <drm/ttm/ttm_placement.h>
 #include "vmwgfx_so.h"
 #include "vmwgfx_binding.h"
+#include "vmwgfx_mksstat.h"
 
 #define VMW_RES_HT_ORDER 12
 
@@ -4406,6 +4407,9 @@ int vmw_execbuf_ioctl(struct drm_device *dev, void *data,
 	int ret;
 	struct dma_fence *in_fence = NULL;
 
+	MKS_STAT_TIME_DECL(MKSSTAT_KERN_EXECBUF);
+	MKS_STAT_TIME_PUSH(MKSSTAT_KERN_EXECBUF);
+
 	/*
 	 * Extend the ioctl argument while maintaining backwards compatibility:
 	 * We take different code paths depending on the value of arg->version.
@@ -4415,7 +4419,8 @@ int vmw_execbuf_ioctl(struct drm_device *dev, void *data,
 	if (unlikely(arg->version > DRM_VMW_EXECBUF_VERSION ||
 		     arg->version == 0)) {
 		VMW_DEBUG_USER("Incorrect execbuf version.\n");
-		return -EINVAL;
+		ret = -EINVAL;
+		goto mksstats_out;
 	}
 
 	switch (arg->version) {
@@ -4435,7 +4440,8 @@ int vmw_execbuf_ioctl(struct drm_device *dev, void *data,
 
 		if (!in_fence) {
 			VMW_DEBUG_USER("Cannot get imported fence\n");
-			return -EINVAL;
+			ret = -EINVAL;
+			goto mksstats_out;
 		}
 
 		ret = vmw_wait_dma_fence(dev_priv->fman, in_fence);
@@ -4458,5 +4464,8 @@ int vmw_execbuf_ioctl(struct drm_device *dev, void *data,
 out:
 	if (in_fence)
 		dma_fence_put(in_fence);
+
+mksstats_out:
+	MKS_STAT_TIME_POP(MKSSTAT_KERN_EXECBUF);
 	return ret;
 }

drivers/gpu/drm/vmwgfx/vmwgfx_mksstat.h

+/* SPDX-License-Identifier: GPL-2.0 OR MIT */
+/**************************************************************************
+ *
+ * Copyright 2021 VMware, Inc., Palo Alto, CA., USA
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the
+ * "Software"), to deal in the Software without restriction, including
+ * without limitation the rights to use, copy, modify, merge, publish,
+ * distribute, sub license, and/or sell copies of the Software, and to
+ * permit persons to whom the Software is furnished to do so, subject to
+ * the following conditions:
+ *
+ * The above copyright notice and this permission notice (including the
+ * next paragraph) shall be included in all copies or substantial portions
+ * of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL
+ * THE COPYRIGHT HOLDERS, AUTHORS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM,
+ * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
+ * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
+ * USE OR OTHER DEALINGS IN THE SOFTWARE.
+ *
+ **************************************************************************/
+
+#ifndef _VMWGFX_MKSSTAT_H_
+#define _VMWGFX_MKSSTAT_H_
+
+#include <asm/page.h>
+
+/* Reservation marker for mksstat pid's */
+#define MKSSTAT_PID_RESERVED -1
+
+#if IS_ENABLED(CONFIG_DRM_VMWGFX_MKSSTATS)
+/*
+ * Kernel-internal mksGuestStat counters. The order of this enum dictates the
+ * order of instantiation of these counters in the mksGuestStat pages.
+ */
+
+typedef enum {
+	MKSSTAT_KERN_EXECBUF, /* vmw_execbuf_ioctl */
+
+	MKSSTAT_KERN_COUNT /* Reserved entry; always last */
+} mksstat_kern_stats_t;
+
+/**
+ * vmw_mksstat_get_kern_pstat: Computes the address of the MKSGuestStatCounterTime
+ * array from the address of the base page.
+ *
+ * @page_addr: Pointer to the base page.
+ * Return: Pointer to the MKSGuestStatCounterTime array.
+ */
+
+static inline void *vmw_mksstat_get_kern_pstat(void *page_addr)
+{
+	return page_addr + PAGE_SIZE * 1;
+}
+
+/**
+ * vmw_mksstat_get_kern_pinfo: Computes the address of the MKSGuestStatInfoEntry
+ * array from the address of the base page.
+ *
+ * @page_addr: Pointer to the base page.
+ * Return: Pointer to the MKSGuestStatInfoEntry array.
+ */
+
+static inline void *vmw_mksstat_get_kern_pinfo(void *page_addr)
+{
+	return page_addr + PAGE_SIZE * 2;
+}
+
+/**
+ * vmw_mksstat_get_kern_pstrs: Computes the address of the mksGuestStat strings
+ * sequence from the address of the base page.
+ *
+ * @page_addr: Pointer to the base page.
+ * Return: Pointer to the mksGuestStat strings sequence.
+ */
+
+static inline void *vmw_mksstat_get_kern_pstrs(void *page_addr)
+{
+	return page_addr + PAGE_SIZE * 3;
+}
+
+/*
+ * MKS_STAT_TIME_DECL/PUSH/POP macros to be used in timer-counted routines.
+ */
+
+struct mksstat_timer_t {
+/* mutable */ mksstat_kern_stats_t old_top;
+	const u64 t0;
+	const int slot;
+};
+
+#define MKS_STAT_TIME_DECL(kern_cntr)                                     \
+	struct mksstat_timer_t _##kern_cntr = {                           \
+		.t0 = rdtsc(),                                            \
+		.slot = vmw_mksstat_get_kern_slot(current->pid, dev_priv) \
+	}
+
+#define MKS_STAT_TIME_PUSH(kern_cntr)                                                               \
+	do {                                                                                        \
+		if (_##kern_cntr.slot >= 0) {                                                       \
+			_##kern_cntr.old_top = dev_priv->mksstat_kern_top_timer[_##kern_cntr.slot]; \
+			dev_priv->mksstat_kern_top_timer[_##kern_cntr.slot] = kern_cntr;            \
+		}                                                                                   \
+	} while (0)
+
+#define MKS_STAT_TIME_POP(kern_cntr)                                                                                                           \
+	do {                                                                                                                                   \
+		if (_##kern_cntr.slot >= 0) {                                                                                                  \
+			const pid_t pid = atomic_cmpxchg(&dev_priv->mksstat_kern_pids[_##kern_cntr.slot], current->pid, MKSSTAT_PID_RESERVED); \
+			dev_priv->mksstat_kern_top_timer[_##kern_cntr.slot] = _##kern_cntr.old_top;                                            \
+			                                                                                                                       \
+			if (pid == current->pid) {                                                                                             \
+				const u64 dt = rdtsc() - _##kern_cntr.t0;                                                                      \
+				MKSGuestStatCounterTime *pstat;                                                                                \
+				                                                                                                               \
+				BUG_ON(!dev_priv->mksstat_kern_pages[_##kern_cntr.slot]);                                                      \
+				                                                                                                               \
+				pstat = vmw_mksstat_get_kern_pstat(page_address(dev_priv->mksstat_kern_pages[_##kern_cntr.slot]));             \
+				                                                                                                               \
+				atomic64_inc(&pstat[kern_cntr].counter.count);                                                                 \
+				atomic64_add(dt, &pstat[kern_cntr].selfCycles);                                                                \
+				atomic64_add(dt, &pstat[kern_cntr].totalCycles);                                                               \
+				                                                                                                               \
+				if (_##kern_cntr.old_top != MKSSTAT_KERN_COUNT)                                                                \
+					atomic64_sub(dt, &pstat[_##kern_cntr.old_top].selfCycles);                                             \
+					                                                                                                       \
+				atomic_set(&dev_priv->mksstat_kern_pids[_##kern_cntr.slot], current->pid);                                     \
+			}                                                                                                                      \
+		}                                                                                                                              \
+	} while (0)
+
+#else
+#define MKS_STAT_TIME_DECL(kern_cntr)
+#define MKS_STAT_TIME_PUSH(kern_cntr)
+#define MKS_STAT_TIME_POP(kern_cntr)
+
+#endif /* IS_ENABLED(CONFIG_DRM_VMWGFX_MKSSTATS */
+
+#endif

include/uapi/drm/vmwgfx_drm.h

@@ -72,6 +72,9 @@ extern "C" {
 #define DRM_VMW_GB_SURFACE_CREATE_EXT   27
 #define DRM_VMW_GB_SURFACE_REF_EXT      28
 #define DRM_VMW_MSG                     29
+#define DRM_VMW_MKSSTAT_RESET           30
+#define DRM_VMW_MKSSTAT_ADD             31
+#define DRM_VMW_MKSSTAT_REMOVE          32
 
 /*************************************************************************/
 /**
@@ -1236,6 +1239,44 @@ struct drm_vmw_msg_arg {
 	__u32 receive_len;
 };
 
+/**
+ * struct drm_vmw_mksstat_add_arg
+ *
+ * @stat: Pointer to user-space stat-counters array, page-aligned.
+ * @info: Pointer to user-space counter-infos array, page-aligned.
+ * @strs: Pointer to user-space stat strings, page-aligned.
+ * @stat_len: Length in bytes of stat-counters array.
+ * @info_len: Length in bytes of counter-infos array.
+ * @strs_len: Length in bytes of the stat strings, terminators included.
+ * @description: Pointer to instance descriptor string; will be truncated
+ *               to MKS_GUEST_STAT_INSTANCE_DESC_LENGTH chars.
+ * @id: Output identifier of the produced record; -1 if error.
+ *
+ * Argument to the DRM_VMW_MKSSTAT_ADD ioctl.
+ */
+struct drm_vmw_mksstat_add_arg {
+	__u64 stat;
+	__u64 info;
+	__u64 strs;
+	__u64 stat_len;
+	__u64 info_len;
+	__u64 strs_len;
+	__u64 description;
+	__u64 id;
+};
+
+/**
+ * struct drm_vmw_mksstat_remove_arg
+ *
+ * @id: Identifier of the record being disposed, originally obtained through
+ *      DRM_VMW_MKSSTAT_ADD ioctl.
+ *
+ * Argument to the DRM_VMW_MKSSTAT_REMOVE ioctl.
+ */
+struct drm_vmw_mksstat_remove_arg {
+	__u64 id;
+};
+
 #if defined(__cplusplus)
 }
 #endif