From 045d1fb79616f138a2e51f04537acd40b9a38ce0 Mon Sep 17 00:00:00 2001 From: Chris Wilson Date: Thu, 5 Dec 2019 21:58:42 +0000 Subject: [PATCH] drm/i915/gt: Acquire a GT wakeref for the breadcrumb interrupt Take a wakeref on the intel_gt specifically for the enabled breadcrumb interrupt so that we can safely process the mmio. If the intel_gt is already asleep by the time we try and setup the breadcrumb interrupt, by a process of elimination we know the request must have been completed and we can skip its enablement! <4> [1518.350005] Unclaimed write to register 0x220a8 <4> [1518.350323] WARNING: CPU: 2 PID: 3685 at drivers/gpu/drm/i915/intel_uncore.c:1163 __unclaimed_reg_debug+0x40/0x50 [i915] <4> [1518.350393] Modules linked in: vgem snd_hda_codec_hdmi x86_pkg_temp_thermal i915 coretemp crct10dif_pclmul crc32_pclmul ghash_clmulni_intel snd_hda_intel snd_intel_dspcfg snd_hda_codec snd_hwdep snd_hda_core btusb cdc_ether btrtl usbnet btbcm btintel r8152 snd_pcm mii bluetooth ecdh_generic ecc i2c_hid pinctrl_sunrisepoint pinctrl_intel intel_lpss_pci prime_numbers [last unloaded: vgem] <4> [1518.350646] CPU: 2 PID: 3685 Comm: gem_exec_parse_ Tainted: G U 5.4.0-rc8-CI-CI_DRM_7490+ #1 <4> [1518.350708] Hardware name: Google Caroline/Caroline, BIOS MrChromebox 08/27/2018 <4> [1518.350946] RIP: 0010:__unclaimed_reg_debug+0x40/0x50 [i915] <4> [1518.350992] Code: 74 05 5b 5d 41 5c c3 45 84 e4 48 c7 c0 95 8d 47 a0 48 c7 c6 8b 8d 47 a0 48 0f 44 f0 89 ea 48 c7 c7 9e 8d 47 a0 e8 40 45 e3 e0 <0f> 0b 83 2d 27 4f 2a 00 01 5b 5d 41 5c c3 66 90 41 55 41 54 55 53 <4> [1518.351100] RSP: 0018:ffffc900007f39c8 EFLAGS: 00010086 <4> [1518.351140] RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000006 <4> [1518.351202] RDX: 0000000080000006 RSI: 0000000000000000 RDI: 00000000ffffffff <4> [1518.351249] RBP: 00000000000220a8 R08: 0000000000000000 R09: 0000000000000000 <4> [1518.351296] R10: ffffc900007f3990 R11: ffffc900007f3868 R12: 0000000000000000 <4> [1518.351342] R13: 00000000fefeffff R14: 0000000000000092 R15: ffff888155fea000 <4> [1518.351391] FS: 00007fc255abfe40(0000) GS:ffff88817ab00000(0000) knlGS:0000000000000000 <4> [1518.351445] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 <4> [1518.351485] CR2: 00007fc2554882d0 CR3: 0000000168ca2005 CR4: 00000000003606e0 <4> [1518.351529] Call Trace: <4> [1518.351746] fwtable_write32+0x114/0x1d0 [i915] <4> [1518.351795] ? sync_file_alloc+0x80/0x80 <4> [1518.352039] gen8_logical_ring_enable_irq+0x30/0x50 [i915] <4> [1518.352295] irq_enable.part.10+0x23/0x40 [i915] <4> [1518.352523] i915_request_enable_breadcrumb+0xb5/0x330 [i915] <4> [1518.352575] ? sync_file_alloc+0x80/0x80 <4> [1518.352612] __dma_fence_enable_signaling+0x60/0x160 <4> [1518.352653] ? sync_file_alloc+0x80/0x80 <4> [1518.352685] dma_fence_add_callback+0x44/0xd0 <4> [1518.352726] sync_file_poll+0x95/0xc0 <4> [1518.352767] do_sys_poll+0x24d/0x570 Signed-off-by: Chris Wilson Reviewed-by: Tvrtko Ursulin Link: https://patchwork.freedesktop.org/patch/msgid/20191205215842.862750-1-chris@chris-wilson.co.uk --- drivers/gpu/drm/i915/gt/intel_breadcrumbs.c | 22 ++++++++++++++++------ 1 file changed, 16 insertions(+), 6 deletions(-) diff --git a/drivers/gpu/drm/i915/gt/intel_breadcrumbs.c b/drivers/gpu/drm/i915/gt/intel_breadcrumbs.c index 5531708..8a9facf4 100644 --- a/drivers/gpu/drm/i915/gt/intel_breadcrumbs.c +++ b/drivers/gpu/drm/i915/gt/intel_breadcrumbs.c @@ -28,6 +28,7 @@ #include "i915_drv.h" #include "i915_trace.h" +#include "intel_gt_pm.h" static void irq_enable(struct intel_engine_cs *engine) { @@ -53,15 +54,17 @@ static void irq_disable(struct intel_engine_cs *engine) static void __intel_breadcrumbs_disarm_irq(struct intel_breadcrumbs *b) { + struct intel_engine_cs *engine = + container_of(b, struct intel_engine_cs, breadcrumbs); + lockdep_assert_held(&b->irq_lock); GEM_BUG_ON(!b->irq_enabled); if (!--b->irq_enabled) - irq_disable(container_of(b, - struct intel_engine_cs, - breadcrumbs)); + irq_disable(engine); b->irq_armed = false; + intel_gt_pm_put_async(engine->gt); } void intel_engine_disarm_breadcrumbs(struct intel_engine_cs *engine) @@ -207,14 +210,17 @@ static void signal_irq_work(struct irq_work *work) intel_engine_breadcrumbs_irq(engine); } -static void __intel_breadcrumbs_arm_irq(struct intel_breadcrumbs *b) +static bool __intel_breadcrumbs_arm_irq(struct intel_breadcrumbs *b) { struct intel_engine_cs *engine = container_of(b, struct intel_engine_cs, breadcrumbs); lockdep_assert_held(&b->irq_lock); if (b->irq_armed) - return; + return true; + + if (!intel_gt_pm_get_if_awake(engine->gt)) + return false; /* * The breadcrumb irq will be disarmed on the interrupt after the @@ -234,6 +240,8 @@ static void __intel_breadcrumbs_arm_irq(struct intel_breadcrumbs *b) if (!b->irq_enabled++) irq_enable(engine); + + return true; } void intel_engine_init_breadcrumbs(struct intel_engine_cs *engine) @@ -277,7 +285,8 @@ bool i915_request_enable_breadcrumb(struct i915_request *rq) spin_lock(&b->irq_lock); GEM_BUG_ON(test_bit(I915_FENCE_FLAG_SIGNAL, &rq->fence.flags)); - __intel_breadcrumbs_arm_irq(b); + if (!__intel_breadcrumbs_arm_irq(b)) + goto unlock; /* * We keep the seqno in retirement order, so we can break @@ -306,6 +315,7 @@ bool i915_request_enable_breadcrumb(struct i915_request *rq) GEM_BUG_ON(!check_signal_order(ce, rq)); set_bit(I915_FENCE_FLAG_SIGNAL, &rq->fence.flags); +unlock: spin_unlock(&b->irq_lock); } -- 2.7.4