linux/drivers/gpu/drm/i915/gvt/aperture_gm.c
Changbin Du 969b0950a1 drm/i915: Add interface to reserve fence registers for vGPU
In the past, vGPU alloc fence registers by walking through mm.fence_list
to find fence which pin_count = 0 and vma is empty. vGPU may not find
enough fence registers this way. Because a fence can be bind to vma even
though it is not in using. We have found such failure many times these
days.

An option to resolve this issue is that we can force-remove fence from
vma in this case.

This patch added two new api to the fence management code:
 - i915_reserve_fence() will try to find a free fence from fence_list
   and force-remove vma if need.
 - i915_unreserve_fence() reclaim a reserved fence after vGPU has
   finished.

With this change, the fence management is more clear to work with vGPU.
GVTg do not need remove fence from fence_list in private.

v3: (Chris)
  - Add struct_mutex lock assertion.
  - Only count for unpinned fence.

v2: (Chris)
  - Rename the new api for symmetry.
  - Add safeguard to ensure at least 1 fence remained for host display.

Signed-off-by: Changbin Du <changbin.du@intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/1504512061-5892-1-git-send-email-changbin.du@intel.com
Acked-by: Zhenyu Wang <zhenyuw@linux.intel.com>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
2017-09-04 16:34:59 +01:00

358 lines
9.3 KiB
C

/*
* Copyright(c) 2011-2016 Intel Corporation. All rights reserved.
*
* 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, sublicense,
* 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 NONINFRINGEMENT. IN NO EVENT SHALL
* THE AUTHORS OR COPYRIGHT HOLDERS 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.
*
* Authors:
* Kevin Tian <kevin.tian@intel.com>
* Dexuan Cui
*
* Contributors:
* Pei Zhang <pei.zhang@intel.com>
* Min He <min.he@intel.com>
* Niu Bing <bing.niu@intel.com>
* Yulei Zhang <yulei.zhang@intel.com>
* Zhenyu Wang <zhenyuw@linux.intel.com>
* Zhi Wang <zhi.a.wang@intel.com>
*
*/
#include "i915_drv.h"
#include "gvt.h"
static int alloc_gm(struct intel_vgpu *vgpu, bool high_gm)
{
struct intel_gvt *gvt = vgpu->gvt;
struct drm_i915_private *dev_priv = gvt->dev_priv;
unsigned int flags;
u64 start, end, size;
struct drm_mm_node *node;
int ret;
if (high_gm) {
node = &vgpu->gm.high_gm_node;
size = vgpu_hidden_sz(vgpu);
start = ALIGN(gvt_hidden_gmadr_base(gvt), I915_GTT_PAGE_SIZE);
end = ALIGN(gvt_hidden_gmadr_end(gvt), I915_GTT_PAGE_SIZE);
flags = PIN_HIGH;
} else {
node = &vgpu->gm.low_gm_node;
size = vgpu_aperture_sz(vgpu);
start = ALIGN(gvt_aperture_gmadr_base(gvt), I915_GTT_PAGE_SIZE);
end = ALIGN(gvt_aperture_gmadr_end(gvt), I915_GTT_PAGE_SIZE);
flags = PIN_MAPPABLE;
}
mutex_lock(&dev_priv->drm.struct_mutex);
ret = i915_gem_gtt_insert(&dev_priv->ggtt.base, node,
size, I915_GTT_PAGE_SIZE,
I915_COLOR_UNEVICTABLE,
start, end, flags);
mutex_unlock(&dev_priv->drm.struct_mutex);
if (ret)
gvt_err("fail to alloc %s gm space from host\n",
high_gm ? "high" : "low");
return ret;
}
static int alloc_vgpu_gm(struct intel_vgpu *vgpu)
{
struct intel_gvt *gvt = vgpu->gvt;
struct drm_i915_private *dev_priv = gvt->dev_priv;
int ret;
ret = alloc_gm(vgpu, false);
if (ret)
return ret;
ret = alloc_gm(vgpu, true);
if (ret)
goto out_free_aperture;
gvt_dbg_core("vgpu%d: alloc low GM start %llx size %llx\n", vgpu->id,
vgpu_aperture_offset(vgpu), vgpu_aperture_sz(vgpu));
gvt_dbg_core("vgpu%d: alloc high GM start %llx size %llx\n", vgpu->id,
vgpu_hidden_offset(vgpu), vgpu_hidden_sz(vgpu));
return 0;
out_free_aperture:
mutex_lock(&dev_priv->drm.struct_mutex);
drm_mm_remove_node(&vgpu->gm.low_gm_node);
mutex_unlock(&dev_priv->drm.struct_mutex);
return ret;
}
static void free_vgpu_gm(struct intel_vgpu *vgpu)
{
struct drm_i915_private *dev_priv = vgpu->gvt->dev_priv;
mutex_lock(&dev_priv->drm.struct_mutex);
drm_mm_remove_node(&vgpu->gm.low_gm_node);
drm_mm_remove_node(&vgpu->gm.high_gm_node);
mutex_unlock(&dev_priv->drm.struct_mutex);
}
/**
* intel_vgpu_write_fence - write fence registers owned by a vGPU
* @vgpu: vGPU instance
* @fence: vGPU fence register number
* @value: Fence register value to be written
*
* This function is used to write fence registers owned by a vGPU. The vGPU
* fence register number will be translated into HW fence register number.
*
*/
void intel_vgpu_write_fence(struct intel_vgpu *vgpu,
u32 fence, u64 value)
{
struct intel_gvt *gvt = vgpu->gvt;
struct drm_i915_private *dev_priv = gvt->dev_priv;
struct drm_i915_fence_reg *reg;
i915_reg_t fence_reg_lo, fence_reg_hi;
assert_rpm_wakelock_held(dev_priv);
if (WARN_ON(fence > vgpu_fence_sz(vgpu)))
return;
reg = vgpu->fence.regs[fence];
if (WARN_ON(!reg))
return;
fence_reg_lo = FENCE_REG_GEN6_LO(reg->id);
fence_reg_hi = FENCE_REG_GEN6_HI(reg->id);
I915_WRITE(fence_reg_lo, 0);
POSTING_READ(fence_reg_lo);
I915_WRITE(fence_reg_hi, upper_32_bits(value));
I915_WRITE(fence_reg_lo, lower_32_bits(value));
POSTING_READ(fence_reg_lo);
}
static void _clear_vgpu_fence(struct intel_vgpu *vgpu)
{
int i;
for (i = 0; i < vgpu_fence_sz(vgpu); i++)
intel_vgpu_write_fence(vgpu, i, 0);
}
static void free_vgpu_fence(struct intel_vgpu *vgpu)
{
struct intel_gvt *gvt = vgpu->gvt;
struct drm_i915_private *dev_priv = gvt->dev_priv;
struct drm_i915_fence_reg *reg;
u32 i;
if (WARN_ON(!vgpu_fence_sz(vgpu)))
return;
intel_runtime_pm_get(dev_priv);
mutex_lock(&dev_priv->drm.struct_mutex);
_clear_vgpu_fence(vgpu);
for (i = 0; i < vgpu_fence_sz(vgpu); i++) {
reg = vgpu->fence.regs[i];
i915_unreserve_fence(reg);
vgpu->fence.regs[i] = NULL;
}
mutex_unlock(&dev_priv->drm.struct_mutex);
intel_runtime_pm_put(dev_priv);
}
static int alloc_vgpu_fence(struct intel_vgpu *vgpu)
{
struct intel_gvt *gvt = vgpu->gvt;
struct drm_i915_private *dev_priv = gvt->dev_priv;
struct drm_i915_fence_reg *reg;
int i;
intel_runtime_pm_get(dev_priv);
/* Request fences from host */
mutex_lock(&dev_priv->drm.struct_mutex);
for (i = 0; i < vgpu_fence_sz(vgpu); i++) {
reg = i915_reserve_fence(dev_priv);
if (IS_ERR(reg))
goto out_free_fence;
vgpu->fence.regs[i] = reg;
}
_clear_vgpu_fence(vgpu);
mutex_unlock(&dev_priv->drm.struct_mutex);
intel_runtime_pm_put(dev_priv);
return 0;
out_free_fence:
gvt_vgpu_err("Failed to alloc fences\n");
/* Return fences to host, if fail */
for (i = 0; i < vgpu_fence_sz(vgpu); i++) {
reg = vgpu->fence.regs[i];
if (!reg)
continue;
i915_unreserve_fence(reg);
vgpu->fence.regs[i] = NULL;
}
mutex_unlock(&dev_priv->drm.struct_mutex);
intel_runtime_pm_put(dev_priv);
return -ENOSPC;
}
static void free_resource(struct intel_vgpu *vgpu)
{
struct intel_gvt *gvt = vgpu->gvt;
gvt->gm.vgpu_allocated_low_gm_size -= vgpu_aperture_sz(vgpu);
gvt->gm.vgpu_allocated_high_gm_size -= vgpu_hidden_sz(vgpu);
gvt->fence.vgpu_allocated_fence_num -= vgpu_fence_sz(vgpu);
}
static int alloc_resource(struct intel_vgpu *vgpu,
struct intel_vgpu_creation_params *param)
{
struct intel_gvt *gvt = vgpu->gvt;
unsigned long request, avail, max, taken;
const char *item;
if (!param->low_gm_sz || !param->high_gm_sz || !param->fence_sz) {
gvt_vgpu_err("Invalid vGPU creation params\n");
return -EINVAL;
}
item = "low GM space";
max = gvt_aperture_sz(gvt) - HOST_LOW_GM_SIZE;
taken = gvt->gm.vgpu_allocated_low_gm_size;
avail = max - taken;
request = MB_TO_BYTES(param->low_gm_sz);
if (request > avail)
goto no_enough_resource;
vgpu_aperture_sz(vgpu) = ALIGN(request, I915_GTT_PAGE_SIZE);
item = "high GM space";
max = gvt_hidden_sz(gvt) - HOST_HIGH_GM_SIZE;
taken = gvt->gm.vgpu_allocated_high_gm_size;
avail = max - taken;
request = MB_TO_BYTES(param->high_gm_sz);
if (request > avail)
goto no_enough_resource;
vgpu_hidden_sz(vgpu) = ALIGN(request, I915_GTT_PAGE_SIZE);
item = "fence";
max = gvt_fence_sz(gvt) - HOST_FENCE;
taken = gvt->fence.vgpu_allocated_fence_num;
avail = max - taken;
request = param->fence_sz;
if (request > avail)
goto no_enough_resource;
vgpu_fence_sz(vgpu) = request;
gvt->gm.vgpu_allocated_low_gm_size += MB_TO_BYTES(param->low_gm_sz);
gvt->gm.vgpu_allocated_high_gm_size += MB_TO_BYTES(param->high_gm_sz);
gvt->fence.vgpu_allocated_fence_num += param->fence_sz;
return 0;
no_enough_resource:
gvt_err("fail to allocate resource %s\n", item);
gvt_err("request %luMB avail %luMB max %luMB taken %luMB\n",
BYTES_TO_MB(request), BYTES_TO_MB(avail),
BYTES_TO_MB(max), BYTES_TO_MB(taken));
return -ENOSPC;
}
/**
* inte_gvt_free_vgpu_resource - free HW resource owned by a vGPU
* @vgpu: a vGPU
*
* This function is used to free the HW resource owned by a vGPU.
*
*/
void intel_vgpu_free_resource(struct intel_vgpu *vgpu)
{
free_vgpu_gm(vgpu);
free_vgpu_fence(vgpu);
free_resource(vgpu);
}
/**
* intel_vgpu_reset_resource - reset resource state owned by a vGPU
* @vgpu: a vGPU
*
* This function is used to reset resource state owned by a vGPU.
*
*/
void intel_vgpu_reset_resource(struct intel_vgpu *vgpu)
{
struct drm_i915_private *dev_priv = vgpu->gvt->dev_priv;
intel_runtime_pm_get(dev_priv);
_clear_vgpu_fence(vgpu);
intel_runtime_pm_put(dev_priv);
}
/**
* intel_alloc_vgpu_resource - allocate HW resource for a vGPU
* @vgpu: vGPU
* @param: vGPU creation params
*
* This function is used to allocate HW resource for a vGPU. User specifies
* the resource configuration through the creation params.
*
* Returns:
* zero on success, negative error code if failed.
*
*/
int intel_vgpu_alloc_resource(struct intel_vgpu *vgpu,
struct intel_vgpu_creation_params *param)
{
int ret;
ret = alloc_resource(vgpu, param);
if (ret)
return ret;
ret = alloc_vgpu_gm(vgpu);
if (ret)
goto out_free_resource;
ret = alloc_vgpu_fence(vgpu);
if (ret)
goto out_free_vgpu_gm;
return 0;
out_free_vgpu_gm:
free_vgpu_gm(vgpu);
out_free_resource:
free_resource(vgpu);
return ret;
}