From bccd3b831185e75c4138bc3fd5201f3214dfeb3d Mon Sep 17 00:00:00 2001 From: Chris Wilson Date: Thu, 9 Nov 2017 14:30:19 +0000 Subject: drm/i915: Use trace_printk to provide a death rattle for GEM MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Trying to enable printk debugging for GEM is fraught with the issue of spam; interactions with HW are very frequent and often boring. However, one instance where they are not so boring is just before a BUG; here ftrace provides a facility to dump its ringbuffer on an oops. So for CI let's enable trace_printk() to capture the last exchanges with HW as a death rattle. For example, [ 79.234110] ------------[ cut here ]------------ [ 79.234137] kernel BUG at drivers/gpu/drm/i915/intel_lrc.c:907! [ 79.234145] invalid opcode: 0000 [#1] SMP [ 79.234153] Dumping ftrace buffer: [ 79.234158] --------------------------------- ... [ 79.314044] gem_conc-1059 1..s1 79203443us : intel_lrc_irq_handler: bcs0 out[0]: ctx=5.2, seqno=145 [ 79.314089] gem_conc-1059 1..s. 79220800us : intel_lrc_irq_handler: bcs0 csb[1/1]: status=0x00000018:0x00000005 [ 79.314133] gem_conc-1059 1..s. 79220803us : intel_lrc_irq_handler: bcs0 out[0]: ctx=5.1, seqno=145 [ 79.314177] gem_conc-1062 2..s1 79230458us : intel_lrc_irq_handler: bcs0 in[0]: ctx=8.1, seqno=146 [ 79.314220] gem_conc-1062 2..s1 79230515us : intel_lrc_irq_handler: bcs0 in[0]: ctx=8.2, seqno=147 [ 79.314265] gem_conc-1059 1..s1 79230951us : intel_lrc_irq_handler: bcs0 csb[2/3]: status=0x00000012:0x00000008 [ 79.314309] gem_conc-1059 1..s1 79230954us : intel_lrc_irq_handler: bcs0 out[0]: ctx=8.2, seqno=147 [ 79.314353] gem_conc-1059 1..s1 79230954us : intel_lrc_irq_handler: bcs0 csb[3/3]: status=0x00008002:0x00000008 [ 79.314396] gem_conc-1059 1..s1 79230955us : intel_lrc_irq_handler: bcs0 out[0]: ctx=8.1, seqno=147 [ 79.314402] --------------------------------- v2: Tweak the formatting to be more consistent between in/out. v3: do {} while (0) stub macro protection Suggested-by: Michał Winiarski Signed-off-by: Chris Wilson Cc: Mika Kuoppala Cc: Joonas Lahtinen Cc: Tvrtko Ursulin Reviewed-by: Joonas Lahtinen Link: https://patchwork.freedesktop.org/patch/msgid/20171109143019.16568-1-chris@chris-wilson.co.uk --- drivers/gpu/drm/i915/i915_gem.h | 6 ++++++ 1 file changed, 6 insertions(+) (limited to 'drivers/gpu/drm/i915/i915_gem.h') diff --git a/drivers/gpu/drm/i915/i915_gem.h b/drivers/gpu/drm/i915/i915_gem.h index ee54597465b6..ff42b5f0e981 100644 --- a/drivers/gpu/drm/i915/i915_gem.h +++ b/drivers/gpu/drm/i915/i915_gem.h @@ -44,6 +44,12 @@ #define GEM_DEBUG_BUG_ON(expr) #endif +#if IS_ENABLED(CONFIG_DRM_I915_TRACE_GEM) +#define GEM_TRACE(...) trace_printk(__VA_ARGS__) +#else +#define GEM_TRACE(...) do { } while (0) +#endif + #define I915_NUM_ENGINES 5 #endif /* __I915_GEM_H__ */ -- cgit