From f25a49ab8ab9c1b5587837c8a386b276403f315c Mon Sep 17 00:00:00 2001 From: Colin Xu Date: Sat, 19 May 2018 12:28:54 +0800 Subject: drm/i915/gvt: Use vgpu_lock to protect per vgpu access The patch set splits out 2 small locks from the original big gvt lock: - vgpu_lock protects per-vGPU data and logic, especially the vGPU trap emulation path. - sched_lock protects gvt scheudler structure, context schedule logic and vGPU's schedule data. Use vgpu_lock to replace the gvt big lock. By doing this, the mmio read/write trap path, vgpu virtual event emulation and other vgpu related process, would be protected under per vgpu_lock. v9: - Change commit author since the patches are improved a lot compared with original version. Original author: Pei Zhang - Rebase to latest gvt-staging. v8: - Correct coding and comment style. - Rebase to latest gvt-staging. v7: - Remove gtt_lock since already proteced by gvt_lock and vgpu_lock. - Fix a typo in intel_gvt_deactivate_vgpu, unlock the wrong lock. v6: - Rebase to latest gvt-staging. v5: - Rebase to latest gvt-staging. - intel_vgpu_page_track_handler should use vgpu_lock. v4: - Rebase to latest gvt-staging. - Protect vgpu->active access with vgpu_lock. - Do not wait gpu idle in vgpu_lock. v3: update to latest code base v2: add gvt->lock in function gvt_check_vblank_emulation Performance comparison on Kabylake platform. - Configuration: Host: Ubuntu 16.04. Guest 1 & 2: Ubuntu 16.04. glmark2 score comparison: - Configuration: Host: glxgears. Guests: glmark2. +--------------------------------+-----------------+ | Setup | glmark2 score | +--------------------------------+-----------------+ | unified lock, iommu=on | 58~62 (avg. 60) | +--------------------------------+-----------------+ | unified lock, iommu=igfx_off | 57~61 (avg. 59) | +--------------------------------+-----------------+ | per-logic lock, iommu=on | 60~68 (avg. 64) | +--------------------------------+-----------------+ | per-logic lock, iommu=igfx_off | 61~67 (avg. 64) | +--------------------------------+-----------------+ lock_stat comparison: - Configuration: Stop lock stat immediately after boot up. Boot 2 VM Guests. Run glmark2 in guests. Start perf lock_stat for 20 seconds and stop again. - Legend: c - contentions; w - waittime-avg +------------+-----------------+-----------+---------------+------------+ | | gvt_lock |sched_lock | vgpu_lock | gtt_lock | + lock type; +-----------------+-----------+---------------+------------+ | iommu set | c | w | c | w | c | w | c | w | +------------+-------+---------+----+------+------+--------+-----+------+ | unified; | 20697 | 839 |N/A | N/A | N/A | N/A | N/A | N/A | | on | | | | | | | | | +------------+-------+---------+----+------+------+--------+-----+------+ | unified; | 21838 | 658.15 |N/A | N/A | N/A | N/A | N/A | N/A | | igfx_off | | | | | | | | | +------------+-------+---------+----+------+------+--------+-----+------+ | per-logic; | 1553 | 1599.96 |9458|429.97| 5846 | 274.33 | 0 | 0.00 | | on | | | | | | | | | +------------+-------+---------+----+------+------+--------+-----+------+ | per-logic; | 1911 | 1678.32 |8335|445.16| 5451 | 244.80 | 0 | 0.00 | | igfx_off | | | | | | | | | +------------+-------+---------+----+------+------+--------+-----+------+ Signed-off-by: Pei Zhang Signed-off-by: Colin Xu Signed-off-by: Zhenyu Wang --- drivers/gpu/drm/i915/gvt/display.c | 35 +++++++++++++++++++---------------- 1 file changed, 19 insertions(+), 16 deletions(-) (limited to 'drivers/gpu/drm/i915/gvt/display.c') diff --git a/drivers/gpu/drm/i915/gvt/display.c b/drivers/gpu/drm/i915/gvt/display.c index 6d8180e8d1e2..8e4a63c5b7d1 100644 --- a/drivers/gpu/drm/i915/gvt/display.c +++ b/drivers/gpu/drm/i915/gvt/display.c @@ -337,26 +337,28 @@ void intel_gvt_check_vblank_emulation(struct intel_gvt *gvt) struct intel_gvt_irq *irq = &gvt->irq; struct intel_vgpu *vgpu; int pipe, id; + int found = false; - if (WARN_ON(!mutex_is_locked(&gvt->lock))) - return; - + mutex_lock(&gvt->lock); for_each_active_vgpu(gvt, vgpu, id) { for (pipe = 0; pipe < I915_MAX_PIPES; pipe++) { - if (pipe_is_enabled(vgpu, pipe)) - goto out; + if (pipe_is_enabled(vgpu, pipe)) { + found = true; + break; + } } + if (found) + break; } /* all the pipes are disabled */ - hrtimer_cancel(&irq->vblank_timer.timer); - return; - -out: - hrtimer_start(&irq->vblank_timer.timer, - ktime_add_ns(ktime_get(), irq->vblank_timer.period), - HRTIMER_MODE_ABS); - + if (!found) + hrtimer_cancel(&irq->vblank_timer.timer); + else + hrtimer_start(&irq->vblank_timer.timer, + ktime_add_ns(ktime_get(), irq->vblank_timer.period), + HRTIMER_MODE_ABS); + mutex_unlock(&gvt->lock); } static void emulate_vblank_on_pipe(struct intel_vgpu *vgpu, int pipe) @@ -393,8 +395,10 @@ static void emulate_vblank(struct intel_vgpu *vgpu) { int pipe; + mutex_lock(&vgpu->vgpu_lock); for_each_pipe(vgpu->gvt->dev_priv, pipe) emulate_vblank_on_pipe(vgpu, pipe); + mutex_unlock(&vgpu->vgpu_lock); } /** @@ -409,11 +413,10 @@ void intel_gvt_emulate_vblank(struct intel_gvt *gvt) struct intel_vgpu *vgpu; int id; - if (WARN_ON(!mutex_is_locked(&gvt->lock))) - return; - + mutex_lock(&gvt->lock); for_each_active_vgpu(gvt, vgpu, id) emulate_vblank(vgpu); + mutex_unlock(&gvt->lock); } /** -- cgit v1.2.3