From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-14.3 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,HK_RANDOM_FROM,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,NICE_REPLY_A,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 6A952C433EF for ; Wed, 22 Sep 2021 15:25:16 +0000 (UTC) Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 2943861181 for ; Wed, 22 Sep 2021 15:25:16 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org 2943861181 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=linux.intel.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=lists.freedesktop.org Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 3BF946EC21; Wed, 22 Sep 2021 15:25:10 +0000 (UTC) Received: from mga12.intel.com (mga12.intel.com [192.55.52.136]) by gabe.freedesktop.org (Postfix) with ESMTPS id F12416EC20; Wed, 22 Sep 2021 15:25:08 +0000 (UTC) X-IronPort-AV: E=McAfee;i="6200,9189,10115"; a="203113802" X-IronPort-AV: E=Sophos;i="5.85,314,1624345200"; d="scan'208";a="203113802" Received: from fmsmga005.fm.intel.com ([10.253.24.32]) by fmsmga106.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 22 Sep 2021 08:25:07 -0700 X-IronPort-AV: E=Sophos;i="5.85,314,1624345200"; d="scan'208";a="704060276" Received: from bbrowne-mobl.ger.corp.intel.com (HELO [10.213.200.151]) ([10.213.200.151]) by fmsmga005-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 22 Sep 2021 08:25:05 -0700 From: Tvrtko Ursulin To: Matthew Brost , dri-devel@lists.freedesktop.org, intel-gfx@lists.freedesktop.org Cc: jani.nikula@linux.intel.com, tvrtko.ursulin@intel.com, lucas.demarchi@intel.com References: <20210922145739.17133-1-matthew.brost@intel.com> Organization: Intel Corporation UK Plc Message-ID: <94ef2f48-5f84-bc4c-0e9f-b1481afd8132@linux.intel.com> Date: Wed, 22 Sep 2021 16:25:04 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.13.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 8bit Subject: Re: [Intel-gfx] [PATCH] drm/i915: Drop stealing of bits from i915_sw_fence function pointer X-BeenThere: intel-gfx@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Intel graphics driver community testing & development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" On 22/09/2021 16:21, Tvrtko Ursulin wrote: > > On 22/09/2021 15:57, Matthew Brost wrote: >> Rather than stealing bits from i915_sw_fence function pointer use >> seperate fields for function pointer and flags. If using two different >> fields, the 4 byte alignment for the i915_sw_fence function pointer can >> also be dropped. >> >> v2: >>   (CI) >>    - Set new function field rather than flags in __i915_sw_fence_init >> >> Signed-off-by: Matthew Brost >> --- >>   drivers/gpu/drm/i915/display/intel_display.c  |  2 +- >>   drivers/gpu/drm/i915/gem/i915_gem_context.c   |  2 +- >>   drivers/gpu/drm/i915/i915_request.c           |  4 ++-- >>   drivers/gpu/drm/i915/i915_sw_fence.c          | 12 +++++------ >>   drivers/gpu/drm/i915/i915_sw_fence.h          | 21 +++++++++---------- >>   drivers/gpu/drm/i915/i915_sw_fence_work.c     |  2 +- >>   .../gpu/drm/i915/selftests/i915_sw_fence.c    |  2 +- >>   drivers/gpu/drm/i915/selftests/lib_sw_fence.c |  4 ++-- >>   8 files changed, 23 insertions(+), 26 deletions(-) >> >> diff --git a/drivers/gpu/drm/i915/display/intel_display.c >> b/drivers/gpu/drm/i915/display/intel_display.c >> index a7ca38613f89..6d5bb55ffc82 100644 >> --- a/drivers/gpu/drm/i915/display/intel_display.c >> +++ b/drivers/gpu/drm/i915/display/intel_display.c >> @@ -10323,7 +10323,7 @@ static void intel_atomic_commit_work(struct >> work_struct *work) >>       intel_atomic_commit_tail(state); >>   } >> -static int __i915_sw_fence_call >> +static int >>   intel_atomic_commit_ready(struct i915_sw_fence *fence, >>                 enum i915_sw_fence_notify notify) >>   { >> diff --git a/drivers/gpu/drm/i915/gem/i915_gem_context.c >> b/drivers/gpu/drm/i915/gem/i915_gem_context.c >> index c2ab0e22db0a..df5fec5c3da8 100644 >> --- a/drivers/gpu/drm/i915/gem/i915_gem_context.c >> +++ b/drivers/gpu/drm/i915/gem/i915_gem_context.c >> @@ -800,7 +800,7 @@ static void free_engines_rcu(struct rcu_head *rcu) >>       free_engines(engines); >>   } >> -static int __i915_sw_fence_call >> +static int >>   engines_notify(struct i915_sw_fence *fence, enum >> i915_sw_fence_notify state) >>   { >>       struct i915_gem_engines *engines = >> diff --git a/drivers/gpu/drm/i915/i915_request.c >> b/drivers/gpu/drm/i915/i915_request.c >> index ce446716d092..945d3025a0b6 100644 >> --- a/drivers/gpu/drm/i915/i915_request.c >> +++ b/drivers/gpu/drm/i915/i915_request.c >> @@ -719,7 +719,7 @@ void i915_request_cancel(struct i915_request *rq, >> int error) >>       intel_context_cancel_request(rq->context, rq); >>   } >> -static int __i915_sw_fence_call >> +static int >>   submit_notify(struct i915_sw_fence *fence, enum i915_sw_fence_notify >> state) >>   { >>       struct i915_request *request = >> @@ -755,7 +755,7 @@ submit_notify(struct i915_sw_fence *fence, enum >> i915_sw_fence_notify state) >>       return NOTIFY_DONE; >>   } >> -static int __i915_sw_fence_call >> +static int >>   semaphore_notify(struct i915_sw_fence *fence, enum >> i915_sw_fence_notify state) >>   { >>       struct i915_request *rq = container_of(fence, typeof(*rq), >> semaphore); >> diff --git a/drivers/gpu/drm/i915/i915_sw_fence.c >> b/drivers/gpu/drm/i915/i915_sw_fence.c >> index c589a681da77..1c080dd1f718 100644 >> --- a/drivers/gpu/drm/i915/i915_sw_fence.c >> +++ b/drivers/gpu/drm/i915/i915_sw_fence.c >> @@ -34,7 +34,7 @@ enum { >>   static void *i915_sw_fence_debug_hint(void *addr) >>   { >> -    return (void *)(((struct i915_sw_fence *)addr)->flags & >> I915_SW_FENCE_MASK); >> +    return (void *)(((struct i915_sw_fence *)addr)->fn); >>   } >>   #ifdef CONFIG_DRM_I915_SW_FENCE_DEBUG_OBJECTS >> @@ -126,10 +126,7 @@ static inline void debug_fence_assert(struct >> i915_sw_fence *fence) >>   static int __i915_sw_fence_notify(struct i915_sw_fence *fence, >>                     enum i915_sw_fence_notify state) >>   { >> -    i915_sw_fence_notify_t fn; >> - >> -    fn = (i915_sw_fence_notify_t)(fence->flags & I915_SW_FENCE_MASK); >> -    return fn(fence, state); >> +    return fence->fn(fence, state); >>   } >>   #ifdef CONFIG_DRM_I915_SW_FENCE_DEBUG_OBJECTS >> @@ -242,10 +239,11 @@ void __i915_sw_fence_init(struct i915_sw_fence >> *fence, >>                 const char *name, >>                 struct lock_class_key *key) >>   { >> -    BUG_ON(!fn || (unsigned long)fn & ~I915_SW_FENCE_MASK); >> +    BUG_ON(!fn); >>       __init_waitqueue_head(&fence->wait, name, key); >> -    fence->flags = (unsigned long)fn; >> +    fence->fn = fn; >> +    fence->flags = 0; >>       i915_sw_fence_reinit(fence); >>   } >> diff --git a/drivers/gpu/drm/i915/i915_sw_fence.h >> b/drivers/gpu/drm/i915/i915_sw_fence.h >> index 30a863353ee6..70ba1789aa89 100644 >> --- a/drivers/gpu/drm/i915/i915_sw_fence.h >> +++ b/drivers/gpu/drm/i915/i915_sw_fence.h >> @@ -17,26 +17,25 @@ >>   struct completion; >>   struct dma_resv; >> +struct i915_sw_fence; >> + >> +enum i915_sw_fence_notify { >> +    FENCE_COMPLETE, >> +    FENCE_FREE >> +}; >> + >> +typedef int (*i915_sw_fence_notify_t)(struct i915_sw_fence *, >> +                      enum i915_sw_fence_notify state); >>   struct i915_sw_fence { >>       wait_queue_head_t wait; >> +    i915_sw_fence_notify_t fn; >>       unsigned long flags; > > Looks good to me. I'd just make the flags narrower now that they can be, > and put them down.. > >>       atomic_t pending; > > .. here as unsigned int and so we save 4 bytes, maybe. No this won't work due test_and_set_bit needs a long, oh well. > > In fact, unless CONFIG_DRM_I915_SW_FENCE_CHECK_DAG is on, which it won't > be on release builds, I don't think anything uses flags any more. So you > could even omit the flags in that case. Might be cumbersome so can leave > for later, but would sure be nice not to waste space if we can avoid it. > > Also please double check if i915_sw_fence_reinit() will be fine and > won't bug on since fence->flags is always zero now I think. But these two are worth checking out. Regards, Tvrtko > > Regards, > > Tvrtko > >>       int error; >>   }; >>   #define I915_SW_FENCE_CHECKED_BIT    0 /* used internally for DAG >> checking */ >> -#define I915_SW_FENCE_PRIVATE_BIT    1 /* available for use by owner */ >> -#define I915_SW_FENCE_MASK        (~3) >> - >> -enum i915_sw_fence_notify { >> -    FENCE_COMPLETE, >> -    FENCE_FREE >> -}; >> - >> -typedef int (*i915_sw_fence_notify_t)(struct i915_sw_fence *, >> -                      enum i915_sw_fence_notify state); >> -#define __i915_sw_fence_call __aligned(4) >>   void __i915_sw_fence_init(struct i915_sw_fence *fence, >>                 i915_sw_fence_notify_t fn, >> diff --git a/drivers/gpu/drm/i915/i915_sw_fence_work.c >> b/drivers/gpu/drm/i915/i915_sw_fence_work.c >> index 5b33ef23d54c..d2e56b387993 100644 >> --- a/drivers/gpu/drm/i915/i915_sw_fence_work.c >> +++ b/drivers/gpu/drm/i915/i915_sw_fence_work.c >> @@ -23,7 +23,7 @@ static void fence_work(struct work_struct *work) >>       dma_fence_put(&f->dma); >>   } >> -static int __i915_sw_fence_call >> +static int >>   fence_notify(struct i915_sw_fence *fence, enum i915_sw_fence_notify >> state) >>   { >>       struct dma_fence_work *f = container_of(fence, typeof(*f), chain); >> diff --git a/drivers/gpu/drm/i915/selftests/i915_sw_fence.c >> b/drivers/gpu/drm/i915/selftests/i915_sw_fence.c >> index cbf45d85cbff..daa985e5a19b 100644 >> --- a/drivers/gpu/drm/i915/selftests/i915_sw_fence.c >> +++ b/drivers/gpu/drm/i915/selftests/i915_sw_fence.c >> @@ -28,7 +28,7 @@ >>   #include "../i915_selftest.h" >> -static int __i915_sw_fence_call >> +static int >>   fence_notify(struct i915_sw_fence *fence, enum i915_sw_fence_notify >> state) >>   { >>       switch (state) { >> diff --git a/drivers/gpu/drm/i915/selftests/lib_sw_fence.c >> b/drivers/gpu/drm/i915/selftests/lib_sw_fence.c >> index 080b90b63d16..eb59a41bdb79 100644 >> --- a/drivers/gpu/drm/i915/selftests/lib_sw_fence.c >> +++ b/drivers/gpu/drm/i915/selftests/lib_sw_fence.c >> @@ -26,7 +26,7 @@ >>   /* Small library of different fence types useful for writing tests */ >> -static int __i915_sw_fence_call >> +static int >>   nop_fence_notify(struct i915_sw_fence *fence, enum >> i915_sw_fence_notify state) >>   { >>       return NOTIFY_DONE; >> @@ -89,7 +89,7 @@ struct heap_fence { >>       }; >>   }; >> -static int __i915_sw_fence_call >> +static int >>   heap_fence_notify(struct i915_sw_fence *fence, enum >> i915_sw_fence_notify state) >>   { >>       struct heap_fence *h = container_of(fence, typeof(*h), fence); >>