dri-devel Archive on lore.kernel.org
 help / color / mirror / Atom feed
From: Mikulas Patocka <mpatocka@redhat.com>
To: Mikulas Patocka <mpatocka@redhat.com>,
	Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>,
	Dave Airlie <airlied@redhat.com>,
	Bernie Thompson <bernie@plugable.com>,
	Ladislav Michl <ladis@linux-mips.org>
Cc: linux-fbdev@vger.kernel.org, dri-devel@lists.freedesktop.org
Subject: [PATCH 08/21] udl-kms: avoid prefetch
Date: Sun, 03 Jun 2018 16:41:01 +0200	[thread overview]
Message-ID: <20180603144221.959741603@twibright.com> (raw)
In-Reply-To: 20180603144053.875668929@twibright.com

[-- Attachment #1: udlkms-avoid-prefetch.patch --]
[-- Type: text/plain, Size: 1749 bytes --]

Modern processors can detect linear memory accesses and prefetch data
automatically, so there's no need to use prefetch.

Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>

---
 drivers/gpu/drm/udl/udl_transfer.c |    7 -------
 1 file changed, 7 deletions(-)

Index: linux-4.16.12/drivers/gpu/drm/udl/udl_transfer.c
===================================================================
--- linux-4.16.12.orig/drivers/gpu/drm/udl/udl_transfer.c	2018-05-31 14:48:12.000000000 +0200
+++ linux-4.16.12/drivers/gpu/drm/udl/udl_transfer.c	2018-05-31 14:48:12.000000000 +0200
@@ -13,7 +13,6 @@
 #include <linux/module.h>
 #include <linux/slab.h>
 #include <linux/fb.h>
-#include <linux/prefetch.h>
 #include <asm/unaligned.h>
 
 #include <drm/drmP.h>
@@ -51,9 +50,6 @@ static int udl_trim_hline(const u8 *bbac
 	int start = width;
 	int end = width;
 
-	prefetch((void *) front);
-	prefetch((void *) back);
-
 	for (j = 0; j < width; j++) {
 		if (back[j] != front[j]) {
 			start = j;
@@ -140,8 +136,6 @@ static void udl_compress_hline16(
 		const u8 *cmd_pixel_start, *cmd_pixel_end = NULL;
 		uint16_t pixel_val16;
 
-		prefetchw((void *) cmd); /* pull in one cache line at least */
-
 		*cmd++ = 0xaf;
 		*cmd++ = 0x6b;
 		*cmd++ = (uint8_t) ((dev_addr >> 16) & 0xFF);
@@ -158,7 +152,6 @@ static void udl_compress_hline16(
 					(unsigned long)(pixel_end - pixel) >> log_bpp,
 					(unsigned long)(cmd_buffer_end - 1 - cmd) / 2) << log_bpp);
 
-		prefetch_range((void *) pixel, cmd_pixel_end - pixel);
 		pixel_val16 = get_pixel_val16(pixel, log_bpp);
 
 		while (pixel < cmd_pixel_end) {

_______________________________________________
dri-devel mailing list
dri-devel@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/dri-devel

  parent reply	other threads:[~2018-06-03 15:18 UTC|newest]

Thread overview: 37+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2018-06-03 14:40 [PATCH 00/21] USB DisplayLink patches Mikulas Patocka
2018-06-03 14:40 ` [PATCH 01/21] udl-kms: fix display corruption of the last line Mikulas Patocka
2018-06-03 14:40 ` [PATCH 02/21] udl-kms: change down_interruptible to down Mikulas Patocka
2018-06-03 14:40 ` [PATCH 03/21] udl-kms: handle allocation failure Mikulas Patocka
2018-06-03 14:40 ` [PATCH 04/21] udl-kms: fix crash due to uninitialized memory Mikulas Patocka
2018-06-03 14:40 ` [PATCH 05/21] udl-kms: fix a linked-list corruption when using fbdefio Mikulas Patocka
2018-06-03 14:40 ` [PATCH 06/21] udl-kms: make a local copy of fb_ops Mikulas Patocka
2018-06-03 14:41 ` [PATCH 07/21] udl-kms: avoid division Mikulas Patocka
2018-06-03 14:41 ` Mikulas Patocka [this message]
2018-06-05 10:08   ` [PATCH 08/21] udl-kms: avoid prefetch Alexey Brodkin
2018-06-05 10:48     ` Ladislav Michl
2018-06-05 15:30     ` Mikulas Patocka
2018-06-06 12:04       ` Alexey Brodkin
2018-06-06 15:46         ` Mikulas Patocka
2018-06-15 16:30           ` Alexey Brodkin
2018-06-03 14:41 ` [PATCH 09/21] udl-kms: use spin_lock_irq instead of spin_lock_irqsave Mikulas Patocka
2018-06-03 14:41 ` [PATCH 10/21] udl-kms: dont spam the syslog with debug messages Mikulas Patocka
2018-06-03 14:41 ` [PATCH 11/21] udlfb: fix semaphore value leak Mikulas Patocka
2018-06-03 14:41 ` [PATCH 12/21] udlfb: fix display corruption of the last line Mikulas Patocka
2018-06-03 14:41 ` [PATCH 13/21] udlfb: dont switch if we are switching to the same videomode Mikulas Patocka
2018-06-03 14:41 ` [PATCH 14/21] udlfb: make a local copy of fb_ops Mikulas Patocka
2018-06-03 14:41 ` [PATCH 15/21] udlfb: set optimal write delay Mikulas Patocka
2018-06-03 14:41 ` [PATCH 16/21] udlfb: handle allocation failure Mikulas Patocka
2018-06-03 14:41 ` [PATCH 17/21] udlfb: set line_length in dlfb_ops_set_par Mikulas Patocka
2018-06-03 14:41 ` [PATCH 18/21] udlfb: allow reallocating the framebuffer Mikulas Patocka
2018-06-03 19:24   ` kbuild test robot
2018-06-12 16:32     ` Mikulas Patocka
2018-07-03 14:58       ` Bartlomiej Zolnierkiewicz
2018-06-03 14:41 ` [PATCH 19/21] udlfb: optimization - test the backing buffer Mikulas Patocka
2018-06-03 14:41 ` [PATCH 20/21] udlfb: avoid prefetch Mikulas Patocka
2018-06-03 14:41 ` [PATCH 21/21] udlfb: use spin_lock_irq instead of spin_lock_irqsave Mikulas Patocka
2018-06-04  1:25 ` [PATCH 00/21] USB DisplayLink patches Dave Airlie
2018-06-04 14:14   ` Mikulas Patocka
2018-07-04  8:04     ` Daniel Vetter
2018-06-05  9:47 ` Alexey Brodkin
2018-06-05 15:34   ` Mikulas Patocka
2018-07-25 13:40     ` Bartlomiej Zolnierkiewicz

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=20180603144221.959741603@twibright.com \
    --to=mpatocka@redhat.com \
    --cc=airlied@redhat.com \
    --cc=b.zolnierkie@samsung.com \
    --cc=bernie@plugable.com \
    --cc=dri-devel@lists.freedesktop.org \
    --cc=ladis@linux-mips.org \
    --cc=linux-fbdev@vger.kernel.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
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox