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=-13.6 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS 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 91DB9C6377B for ; Wed, 21 Jul 2021 20:17:49 +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 594DB60FE7 for ; Wed, 21 Jul 2021 20:17:49 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 594DB60FE7 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=jlekstrand.net Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=intel-gfx-bounces@lists.freedesktop.org Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 80CF76EAD5; Wed, 21 Jul 2021 20:17:44 +0000 (UTC) Received: from mail-yb1-xb2d.google.com (mail-yb1-xb2d.google.com [IPv6:2607:f8b0:4864:20::b2d]) by gabe.freedesktop.org (Postfix) with ESMTPS id 780AA6EAD5 for ; Wed, 21 Jul 2021 20:17:42 +0000 (UTC) Received: by mail-yb1-xb2d.google.com with SMTP id y38so2088446ybi.1 for ; Wed, 21 Jul 2021 13:17:42 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=jlekstrand-net.20150623.gappssmtp.com; s=20150623; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=8KGS30Ot/2ZhAUgNQAxnuzr+NnUh4+CoroaoIQogMBE=; b=D4AXreUtylh9R30Y8bkFVWNvSd5rY97qN6HnqElGPrbEymXJmf8qBqjSu88JYN2fHj GfQprdRfQvxYVEIxGfWMeKFikL+w27sNp+638aYBuIjR7rniA9gN8zSxrz+YSMu3bTRN xQJ0gC13m9d1Get+XbrVRa8aGDz2gcpFF6IuaLcFtpG4Q9KzeTwBPyeNNrg6AGzkDZtN 5L+ljjyB12JSORL8B2htCRND4gI3e8O2XlwdZRz3snlfAaN0tewqEVocSLE5wc/ym+e6 oNcDnEVG49GNja7ELSI3xtEA9H7NBhrIdR4S8j3bgGRmXBEJRXkht9p+RgLtn2WNfgQg vj5w== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=8KGS30Ot/2ZhAUgNQAxnuzr+NnUh4+CoroaoIQogMBE=; b=nVXfPBL7xY1adgKrz+UiwExYDabNvsVqSFaj77cuMF/09s0GivPMKugJPKS/i81HY5 a3xHcyjrsBEmVXpRQDItU+e/IQ+uqm9ZRkbQlNuT5VF58IBv2ajngO9gu3/VyIsiV4rU t/XiH/WmEuj0TudKPAG0GBgJPgO+LTlZUtDC6JbNS/TJxnYvdRIc2r15V6sdJZwrBkdw 3YOM3MsaPbMX2FMcyDZXlkn/hXMIim9k2SIBeEACGKEVYqTxDonsN5xro3aptPuqXDT/ aWNCCPbtsBO00SZYZrNPMH7TbHNvyB+Rz1UX+4VjMm7vbl2Q1Obe8RQ+CiuzdEG3me/t hgPA== X-Gm-Message-State: AOAM533xv2XpZaZfvaUesawGJqFC+mQsz4vHphan8X4s3CtMYHaH1tCM AsJmLxeY/NX+YI9a3uNNbiTtzmT2BzdM/2Ji7YWX4A== X-Google-Smtp-Source: ABdhPJwzj3bO7T+8Esb7jvuADBYIvmdCF3UnQMFLP0iDH5itdQW/5p7RpdsQOfVaT/HD2c3UCKNzOGUvU829UIGY7fA= X-Received: by 2002:a25:2f89:: with SMTP id v131mr48803718ybv.469.1626898661586; Wed, 21 Jul 2021 13:17:41 -0700 (PDT) MIME-Version: 1.0 References: <20210721183229.4136488-1-daniel.vetter@ffwll.ch> In-Reply-To: <20210721183229.4136488-1-daniel.vetter@ffwll.ch> From: Jason Ekstrand Date: Wed, 21 Jul 2021 15:17:30 -0500 Message-ID: To: Daniel Vetter Subject: Re: [Intel-gfx] [PATCH] drm/i915: Ditch i915 globals shrink infrastructure 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: , Cc: David Airlie , Daniel Vetter , Intel Graphics Development , DRI Development Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" On Wed, Jul 21, 2021 at 1:32 PM Daniel Vetter wrote: > > This essentially reverts > > commit 84a1074920523430f9dc30ff907f4801b4820072 > Author: Chris Wilson > Date: Wed Jan 24 11:36:08 2018 +0000 > > drm/i915: Shrink the GEM kmem_caches upon idling > > mm/vmscan.c:do_shrink_slab() is a thing, if there's an issue with it > then we need to fix that there, not hand-roll our own slab shrinking > code in i915. > > Noticed while reviewing a patch set from Jason to fix up some issues > in our i915_init() and i915_exit() module load/cleanup code. Now that > i915_globals.c isn't any different than normal init/exit functions, we > should convert them over to one unified table and remove > i915_globals.[hc] entirely. Mind throwing in a comment somewhere about how i915 is one of only two users of kmem_cache_shrink() in the entire kernel? That also seems to be pretty good evidence that it's not useful. Reviewed-by: Jason Ekstrand Feel free to land at-will and I'll deal with merge conflicts on my end. > Cc: David Airlie > Cc: Jason Ekstrand > Signed-off-by: Daniel Vetter > --- > drivers/gpu/drm/i915/gem/i915_gem_context.c | 6 -- > drivers/gpu/drm/i915/gem/i915_gem_object.c | 6 -- > drivers/gpu/drm/i915/gt/intel_context.c | 6 -- > drivers/gpu/drm/i915/gt/intel_gt_pm.c | 4 - > drivers/gpu/drm/i915/i915_active.c | 6 -- > drivers/gpu/drm/i915/i915_globals.c | 95 --------------------- > drivers/gpu/drm/i915/i915_globals.h | 3 - > drivers/gpu/drm/i915/i915_request.c | 7 -- > drivers/gpu/drm/i915/i915_scheduler.c | 7 -- > drivers/gpu/drm/i915/i915_vma.c | 6 -- > 10 files changed, 146 deletions(-) > > diff --git a/drivers/gpu/drm/i915/gem/i915_gem_context.c b/drivers/gpu/drm/i915/gem/i915_gem_context.c > index 7d6f52d8a801..bf2a2319353a 100644 > --- a/drivers/gpu/drm/i915/gem/i915_gem_context.c > +++ b/drivers/gpu/drm/i915/gem/i915_gem_context.c > @@ -2280,18 +2280,12 @@ i915_gem_engines_iter_next(struct i915_gem_engines_iter *it) > #include "selftests/i915_gem_context.c" > #endif > > -static void i915_global_gem_context_shrink(void) > -{ > - kmem_cache_shrink(global.slab_luts); > -} > - > static void i915_global_gem_context_exit(void) > { > kmem_cache_destroy(global.slab_luts); > } > > static struct i915_global_gem_context global = { { > - .shrink = i915_global_gem_context_shrink, > .exit = i915_global_gem_context_exit, > } }; > > diff --git a/drivers/gpu/drm/i915/gem/i915_gem_object.c b/drivers/gpu/drm/i915/gem/i915_gem_object.c > index 9da7b288b7ed..5c21cff33199 100644 > --- a/drivers/gpu/drm/i915/gem/i915_gem_object.c > +++ b/drivers/gpu/drm/i915/gem/i915_gem_object.c > @@ -664,18 +664,12 @@ void i915_gem_init__objects(struct drm_i915_private *i915) > INIT_WORK(&i915->mm.free_work, __i915_gem_free_work); > } > > -static void i915_global_objects_shrink(void) > -{ > - kmem_cache_shrink(global.slab_objects); > -} > - > static void i915_global_objects_exit(void) > { > kmem_cache_destroy(global.slab_objects); > } > > static struct i915_global_object global = { { > - .shrink = i915_global_objects_shrink, > .exit = i915_global_objects_exit, > } }; > > diff --git a/drivers/gpu/drm/i915/gt/intel_context.c b/drivers/gpu/drm/i915/gt/intel_context.c > index bd63813c8a80..c1338441cc1d 100644 > --- a/drivers/gpu/drm/i915/gt/intel_context.c > +++ b/drivers/gpu/drm/i915/gt/intel_context.c > @@ -398,18 +398,12 @@ void intel_context_fini(struct intel_context *ce) > i915_active_fini(&ce->active); > } > > -static void i915_global_context_shrink(void) > -{ > - kmem_cache_shrink(global.slab_ce); > -} > - > static void i915_global_context_exit(void) > { > kmem_cache_destroy(global.slab_ce); > } > > static struct i915_global_context global = { { > - .shrink = i915_global_context_shrink, > .exit = i915_global_context_exit, > } }; > > diff --git a/drivers/gpu/drm/i915/gt/intel_gt_pm.c b/drivers/gpu/drm/i915/gt/intel_gt_pm.c > index aef3084e8b16..d86825437516 100644 > --- a/drivers/gpu/drm/i915/gt/intel_gt_pm.c > +++ b/drivers/gpu/drm/i915/gt/intel_gt_pm.c > @@ -67,8 +67,6 @@ static int __gt_unpark(struct intel_wakeref *wf) > > GT_TRACE(gt, "\n"); > > - i915_globals_unpark(); > - > /* > * It seems that the DMC likes to transition between the DC states a lot > * when there are no connected displays (no active power domains) during > @@ -116,8 +114,6 @@ static int __gt_park(struct intel_wakeref *wf) > GEM_BUG_ON(!wakeref); > intel_display_power_put_async(i915, POWER_DOMAIN_GT_IRQ, wakeref); > > - i915_globals_park(); > - > return 0; > } > > diff --git a/drivers/gpu/drm/i915/i915_active.c b/drivers/gpu/drm/i915/i915_active.c > index b1aa1c482c32..91723123ae9f 100644 > --- a/drivers/gpu/drm/i915/i915_active.c > +++ b/drivers/gpu/drm/i915/i915_active.c > @@ -1176,18 +1176,12 @@ struct i915_active *i915_active_create(void) > #include "selftests/i915_active.c" > #endif > > -static void i915_global_active_shrink(void) > -{ > - kmem_cache_shrink(global.slab_cache); > -} > - > static void i915_global_active_exit(void) > { > kmem_cache_destroy(global.slab_cache); > } > > static struct i915_global_active global = { { > - .shrink = i915_global_active_shrink, > .exit = i915_global_active_exit, > } }; > > diff --git a/drivers/gpu/drm/i915/i915_globals.c b/drivers/gpu/drm/i915/i915_globals.c > index 77f1911c463b..7fe2e503897b 100644 > --- a/drivers/gpu/drm/i915/i915_globals.c > +++ b/drivers/gpu/drm/i915/i915_globals.c > @@ -17,61 +17,8 @@ > > static LIST_HEAD(globals); > > -static atomic_t active; > -static atomic_t epoch; > -static struct park_work { > - struct delayed_work work; > - struct rcu_head rcu; > - unsigned long flags; > -#define PENDING 0 > - int epoch; > -} park; > - > -static void i915_globals_shrink(void) > -{ > - struct i915_global *global; > - > - /* > - * kmem_cache_shrink() discards empty slabs and reorders partially > - * filled slabs to prioritise allocating from the mostly full slabs, > - * with the aim of reducing fragmentation. > - */ > - list_for_each_entry(global, &globals, link) > - global->shrink(); > -} > - > -static void __i915_globals_grace(struct rcu_head *rcu) > -{ > - /* Ratelimit parking as shrinking is quite slow */ > - schedule_delayed_work(&park.work, round_jiffies_up_relative(2 * HZ)); > -} > - > -static void __i915_globals_queue_rcu(void) > -{ > - park.epoch = atomic_inc_return(&epoch); > - if (!atomic_read(&active)) { > - init_rcu_head(&park.rcu); > - call_rcu(&park.rcu, __i915_globals_grace); > - } > -} > - > -static void __i915_globals_park(struct work_struct *work) > -{ > - destroy_rcu_head(&park.rcu); > - > - /* Confirm nothing woke up in the last grace period */ > - if (park.epoch != atomic_read(&epoch)) { > - __i915_globals_queue_rcu(); > - return; > - } > - > - clear_bit(PENDING, &park.flags); > - i915_globals_shrink(); > -} > - > void __init i915_global_register(struct i915_global *global) > { > - GEM_BUG_ON(!global->shrink); > GEM_BUG_ON(!global->exit); > > list_add_tail(&global->link, &globals); > @@ -109,52 +56,10 @@ int __init i915_globals_init(void) > } > } > > - INIT_DELAYED_WORK(&park.work, __i915_globals_park); > return 0; > } > > -void i915_globals_park(void) > -{ > - /* > - * Defer shrinking the global slab caches (and other work) until > - * after a RCU grace period has completed with no activity. This > - * is to try and reduce the latency impact on the consumers caused > - * by us shrinking the caches the same time as they are trying to > - * allocate, with the assumption being that if we idle long enough > - * for an RCU grace period to elapse since the last use, it is likely > - * to be longer until we need the caches again. > - */ > - if (!atomic_dec_and_test(&active)) > - return; > - > - /* Queue cleanup after the next RCU grace period has freed slabs */ > - if (!test_and_set_bit(PENDING, &park.flags)) > - __i915_globals_queue_rcu(); > -} > - > -void i915_globals_unpark(void) > -{ > - atomic_inc(&epoch); > - atomic_inc(&active); > -} > - > -static void __exit __i915_globals_flush(void) > -{ > - atomic_inc(&active); /* skip shrinking */ > - > - rcu_barrier(); /* wait for the work to be queued */ > - flush_delayed_work(&park.work); > - > - atomic_dec(&active); > -} > - > void __exit i915_globals_exit(void) > { > - GEM_BUG_ON(atomic_read(&active)); > - > - __i915_globals_flush(); > __i915_globals_cleanup(); > - > - /* And ensure that our DESTROY_BY_RCU slabs are truly destroyed */ > - rcu_barrier(); > } > diff --git a/drivers/gpu/drm/i915/i915_globals.h b/drivers/gpu/drm/i915/i915_globals.h > index 2d199f411a4a..9e6b4fd07528 100644 > --- a/drivers/gpu/drm/i915/i915_globals.h > +++ b/drivers/gpu/drm/i915/i915_globals.h > @@ -14,15 +14,12 @@ typedef void (*i915_global_func_t)(void); > struct i915_global { > struct list_head link; > > - i915_global_func_t shrink; > i915_global_func_t exit; > }; > > void i915_global_register(struct i915_global *global); > > int i915_globals_init(void); > -void i915_globals_park(void); > -void i915_globals_unpark(void); > void i915_globals_exit(void); > > /* constructors */ > diff --git a/drivers/gpu/drm/i915/i915_request.c b/drivers/gpu/drm/i915/i915_request.c > index 09ebea9a0090..d3de9f60e03a 100644 > --- a/drivers/gpu/drm/i915/i915_request.c > +++ b/drivers/gpu/drm/i915/i915_request.c > @@ -2077,12 +2077,6 @@ void i915_request_show(struct drm_printer *m, > #include "selftests/i915_request.c" > #endif > > -static void i915_global_request_shrink(void) > -{ > - kmem_cache_shrink(global.slab_execute_cbs); > - kmem_cache_shrink(global.slab_requests); > -} > - > static void i915_global_request_exit(void) > { > kmem_cache_destroy(global.slab_execute_cbs); > @@ -2090,7 +2084,6 @@ static void i915_global_request_exit(void) > } > > static struct i915_global_request global = { { > - .shrink = i915_global_request_shrink, > .exit = i915_global_request_exit, > } }; > > diff --git a/drivers/gpu/drm/i915/i915_scheduler.c b/drivers/gpu/drm/i915/i915_scheduler.c > index 3a58a9130309..561c649e59f7 100644 > --- a/drivers/gpu/drm/i915/i915_scheduler.c > +++ b/drivers/gpu/drm/i915/i915_scheduler.c > @@ -475,12 +475,6 @@ i915_sched_engine_create(unsigned int subclass) > return sched_engine; > } > > -static void i915_global_scheduler_shrink(void) > -{ > - kmem_cache_shrink(global.slab_dependencies); > - kmem_cache_shrink(global.slab_priorities); > -} > - > static void i915_global_scheduler_exit(void) > { > kmem_cache_destroy(global.slab_dependencies); > @@ -488,7 +482,6 @@ static void i915_global_scheduler_exit(void) > } > > static struct i915_global_scheduler global = { { > - .shrink = i915_global_scheduler_shrink, > .exit = i915_global_scheduler_exit, > } }; > > diff --git a/drivers/gpu/drm/i915/i915_vma.c b/drivers/gpu/drm/i915/i915_vma.c > index 5b9dce0f443b..09a7c47926f7 100644 > --- a/drivers/gpu/drm/i915/i915_vma.c > +++ b/drivers/gpu/drm/i915/i915_vma.c > @@ -1414,18 +1414,12 @@ void i915_vma_make_purgeable(struct i915_vma *vma) > #include "selftests/i915_vma.c" > #endif > > -static void i915_global_vma_shrink(void) > -{ > - kmem_cache_shrink(global.slab_vmas); > -} > - > static void i915_global_vma_exit(void) > { > kmem_cache_destroy(global.slab_vmas); > } > > static struct i915_global_vma global = { { > - .shrink = i915_global_vma_shrink, > .exit = i915_global_vma_exit, > } }; > > -- > 2.32.0 > _______________________________________________ Intel-gfx mailing list Intel-gfx@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/intel-gfx