Intel-GFX Archive on lore.kernel.org
 help / color / Atom feed
From: Chris Wilson <chris@chris-wilson.co.uk>
To: intel-gfx@lists.freedesktop.org
Subject: [Intel-gfx] [CI 1/6] drm/i915/gem: Almagamate clflushes on suspend
Date: Tue, 19 Jan 2021 21:43:31 +0000
Message-ID: <20210119214336.1463-1-chris@chris-wilson.co.uk> (raw)

When flushing objects larger than the CPU cache it is preferrable to use
a single wbinvd() rather than overlapping clflush(). At runtime, we
avoid wbinvd() due to its system-wide latencies, but during
singlethreaded suspend, no one will observe the imposed latency and we
can opt for the faster wbinvd to clear all objects in a single hit.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Matthew Auld <matthew.auld@intel.com>
---
 drivers/gpu/drm/i915/gem/i915_gem_pm.c | 41 +++++++++-----------------
 1 file changed, 14 insertions(+), 27 deletions(-)

diff --git a/drivers/gpu/drm/i915/gem/i915_gem_pm.c b/drivers/gpu/drm/i915/gem/i915_gem_pm.c
index 40d3e40500fa..215766cc22bf 100644
--- a/drivers/gpu/drm/i915/gem/i915_gem_pm.c
+++ b/drivers/gpu/drm/i915/gem/i915_gem_pm.c
@@ -11,6 +11,13 @@
 
 #include "i915_drv.h"
 
+#if defined(CONFIG_X86)
+#include <asm/smp.h>
+#else
+#define wbinvd_on_all_cpus() \
+	pr_warn(DRIVER_NAME ": Missing cache flush in %s\n", __func__)
+#endif
+
 void i915_gem_suspend(struct drm_i915_private *i915)
 {
 	GEM_TRACE("%s\n", dev_name(i915->drm.dev));
@@ -32,13 +39,6 @@ void i915_gem_suspend(struct drm_i915_private *i915)
 	i915_gem_drain_freed_objects(i915);
 }
 
-static struct drm_i915_gem_object *first_mm_object(struct list_head *list)
-{
-	return list_first_entry_or_null(list,
-					struct drm_i915_gem_object,
-					mm.link);
-}
-
 void i915_gem_suspend_late(struct drm_i915_private *i915)
 {
 	struct drm_i915_gem_object *obj;
@@ -48,6 +48,7 @@ void i915_gem_suspend_late(struct drm_i915_private *i915)
 		NULL
 	}, **phase;
 	unsigned long flags;
+	bool flush = false;
 
 	/*
 	 * Neither the BIOS, ourselves or any other kernel
@@ -73,29 +74,15 @@ void i915_gem_suspend_late(struct drm_i915_private *i915)
 
 	spin_lock_irqsave(&i915->mm.obj_lock, flags);
 	for (phase = phases; *phase; phase++) {
-		LIST_HEAD(keep);
-
-		while ((obj = first_mm_object(*phase))) {
-			list_move_tail(&obj->mm.link, &keep);
-
-			/* Beware the background _i915_gem_free_objects */
-			if (!kref_get_unless_zero(&obj->base.refcount))
-				continue;
-
-			spin_unlock_irqrestore(&i915->mm.obj_lock, flags);
-
-			i915_gem_object_lock(obj, NULL);
-			drm_WARN_ON(&i915->drm,
-			    i915_gem_object_set_to_gtt_domain(obj, false));
-			i915_gem_object_unlock(obj);
-			i915_gem_object_put(obj);
-
-			spin_lock_irqsave(&i915->mm.obj_lock, flags);
+		list_for_each_entry(obj, *phase, mm.link) {
+			if (!(obj->cache_coherent & I915_BO_CACHE_COHERENT_FOR_READ))
+				flush |= (obj->read_domains & I915_GEM_DOMAIN_CPU) == 0;
+			__start_cpu_write(obj); /* presume auto-hibernate */
 		}
-
-		list_splice_tail(&keep, *phase);
 	}
 	spin_unlock_irqrestore(&i915->mm.obj_lock, flags);
+	if (flush)
+		wbinvd_on_all_cpus();
 }
 
 void i915_gem_resume(struct drm_i915_private *i915)
-- 
2.20.1

_______________________________________________
Intel-gfx mailing list
Intel-gfx@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/intel-gfx

             reply index

Thread overview: 12+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-01-19 21:43 Chris Wilson [this message]
2021-01-19 21:43 ` [Intel-gfx] [CI 2/6] drm/i915/gem: Almagamate clflushes on freeze Chris Wilson
2021-01-19 21:43 ` [Intel-gfx] [CI 3/6] drm/i915/gem: Move stolen node into GEM object union Chris Wilson
2021-01-19 21:43 ` [Intel-gfx] [CI 4/6] drm/i915/gem: Use shrinkable status for unknown swizzle quirks Chris Wilson
2021-01-19 21:43 ` [Intel-gfx] [CI 5/6] drm/i915/gem: Protect used framebuffers from casual eviction Chris Wilson
2021-01-19 21:43 ` [Intel-gfx] [CI 6/6] drm/i915/gem: Drop lru bumping on display unpinning Chris Wilson
2021-02-08 20:09   ` Dave Airlie
2021-01-19 23:05 ` [Intel-gfx] ✗ Fi.CI.CHECKPATCH: warning for series starting with [CI,1/6] drm/i915/gem: Almagamate clflushes on suspend Patchwork
2021-01-19 23:35 ` [Intel-gfx] ✗ Fi.CI.BAT: failure " Patchwork
2021-01-20 15:21 ` [Intel-gfx] ✗ Fi.CI.CHECKPATCH: warning for series starting with [CI,1/6] drm/i915/gem: Almagamate clflushes on suspend (rev2) Patchwork
2021-01-20 15:50 ` [Intel-gfx] ✓ Fi.CI.BAT: success " Patchwork
2021-01-20 17:58 ` [Intel-gfx] ✗ Fi.CI.IGT: failure " Patchwork

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20210119214336.1463-1-chris@chris-wilson.co.uk \
    --to=chris@chris-wilson.co.uk \
    --cc=intel-gfx@lists.freedesktop.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link

Intel-GFX Archive on lore.kernel.org

Archives are clonable:
	git clone --mirror https://lore.kernel.org/intel-gfx/0 intel-gfx/git/0.git
	git clone --mirror https://lore.kernel.org/intel-gfx/1 intel-gfx/git/1.git

	# If you have public-inbox 1.1+ installed, you may
	# initialize and index your mirror using the following commands:
	public-inbox-init -V2 intel-gfx intel-gfx/ https://lore.kernel.org/intel-gfx \
		intel-gfx@lists.freedesktop.org
	public-inbox-index intel-gfx

Example config snippet for mirrors

Newsgroup available over NNTP:
	nntp://nntp.lore.kernel.org/org.freedesktop.lists.intel-gfx


AGPL code for this site: git clone https://public-inbox.org/public-inbox.git