Re: [PATCH][ANNOUNCE] Linux 2.5.68-ce2

Re: [PATCH][ANNOUNCE] Linux 2.5.68-ce2

[Chuck Ebbert]

Zwane Mwaikambo wrote:

.> What benefit did you see from that, what was your reasoning behind the 
.> change? Have you noted 16byte code alignment improvements with some processors?

 I posted a message about that a while ago after noticing that some
interrupt handlers started in the last 4 bytes of a(n assumed) 16-byte
cacheline, and the first instruction in all of them was 5 bytes long.
According to the manuals the penalties for this can be huge, and there's
no way to mitigate them with branch prediction and prefetch.  (How do you
predict an interrupt?)  And even if you hit L1 with both fetches there is
a small penalty...

 I couldn't find any way to test the patch, but there doesn't seem to be
any downside other than a lost 1K of memory on IOAPIC machines, and a possible
larger working set fighting for L1 space but that would require heavy
concurrent use of a very large number of interrupt vectors.


-------
 Chuck

Re: [PATCH][ANNOUNCE] Linux 2.5.68-ce2

[Chuck Ebbert]

Jvrn Engel wrote:


> +#include <linux/cache.h>
> +#define CACHELINE_ALIGN .align L1_CACHE_BYTES,0x90
> ...
> -	ALIGN
> +	CACHELINE_ALIGN



 I just found this in include/linux/linkage.h:


#define CACHE_ALIGN     ALIGN



:(



------
 Chuck

Re: [PATCH][ANNOUNCE] Linux 2.5.68-ce2

[Chuck Ebbert]

Jvrn Engel wrote:


> How about the following?
> 
> +#include <linux/cache.h>
> +#define CACHELINE_ALIGN .align L1_CACHE_BYTES,0x90
> ...
> -	ALIGN
>+	CACHELINE_ALIGN
> ...
>
> Or was this a bad guess of what you wanted to do?


  With 32-byte cachelines it woulf probably be too much wasted
space -- the handlers are only 10 bytes long at worst and some of
them are only 7 bytes.  Maybe packing three of them per cacheline might
work better in that case?


-------
 Chuck

Re: [PATCH][ANNOUNCE] Linux 2.5.68-ce2

[Jörn Engel]

On Tue, 22 April 2003 14:26:21 -0400, Chuck Ebbert wrote:
> diff -u --exclude-from=/home/me/.exclude -r a/arch/i386/kernel/entry.S b/arch/i386/kernel/entry.S
> --- a/arch/i386/kernel/entry.S	Sat Mar 29 09:16:32 2003
> +++ b/arch/i386/kernel/entry.S	Sun Apr 20 14:29:01 2003
> @ -382,10 +382,11 @
>  ENTRY(interrupt)
>  .text
>  
> +	.align 16,0x90			# make ENTRY have correct address
>  vector=0
>  ENTRY(irq_entries_start)
>  .rept NR_IRQS
> -	ALIGN
> +	.align 16,0x90			# should be cacheline-aligned?
>  1:	pushl $vector-256
>  	jmp common_interrupt
>  .data
> @ -394,17 +395,18 @
>  vector=vector+1
>  .endr
>  
> -	ALIGN
> +	.align 16,0x90
>  common_interrupt:
>  	SAVE_ALL
>  	call do_IRQ
>  	jmp ret_from_intr
>  
>  #define BUILD_INTERRUPT(name, nr)	\
> +	.align 16,0x90;			\
>  ENTRY(name)				\
>  	pushl $nr-256;			\
>  	SAVE_ALL			\
> -	call smp_/**/name;	\
> +	call smp_/**/name;		\
>  	jmp ret_from_intr;
>  
>  /* The include is where all of the SMP etc. interrupts come from */

How about the following?

+#include <linux/cache.h>
+#define CACHELINE_ALIGN .align L1_CACHE_BYTES,0x90
...
-	ALIGN
+	CACHELINE_ALIGN
...

Or was this a bad guess of what you wanted to do?

Jörn

-- 
Do not stop an army on its way home.
-- Sun Tzu

[PATCH][ANNOUNCE] Linux 2.5.68-ce2

[Chuck Ebbert]

This patch is a collection of small fixes and enhancements for 2.5.68-release.

 Makefile                        |    2 +-
 arch/i386/kernel/entry.S        |    8 +++++---
 arch/i386/kernel/io_apic.c      |    2 +-
 drivers/char/keyboard.c         |    2 +-
 drivers/ide/ide-probe.c         |    2 +-
 drivers/isdn/tpam/tpam_queues.c |    1 +
 drivers/net/sis900.c            |    1 +
 drivers/net/wan/sdla_ppp.c      |    3 +--
 drivers/pci/bus.c               |    9 ++++++++-
 drivers/pci/probe.c             |    2 +-
 fs/ext3/super.c                 |   12 ++++++------
 fs/fat/inode.c                  |    1 +
 fs/fat/misc.c                   |    1 +
 include/linux/msdos_fs.h        |    3 +--
 mm/vmscan.c                     |   21 ++++++++++++++++++---
 net/ax25/af_ax25.c              |    2 ++
 net/ipv4/netfilter/ip_queue.c   |    8 ++++++--
 net/ipv6/netfilter/ip6_queue.c  |    6 +++++-
 net/irda/irttp.c                |    2 +-
 19 files changed, 62 insertions(+), 26 deletions(-)

extraversion.2.patch					(me)
	change extraversion to -ce2
checker.1.patch						(Muli Ben-Yehuda)
	6 checker fixes from lkml
irq_align.2.patch					(me)
	16-byte align interrupt entry points
pci_probe.1.patch					(?, from 2.5.68-mm1)
	1-line fix from mm1
pci_bus.1.patch						(me, from 2.5.68-mm1)
	fix global pci device list order
kbd.1.patch						(Chris Heath)
	fix SAK in raw mode
ide_probe.1.patch					(Manfred Spraul)
	fix ide probe return codes
ext3.1.patch						(Ernie Petrides)
	fix bug in ext3_orphan_cleanup()
fat.1.patch						(Bjvrn Stenberg)
	make fat use next_cluster field
io_apic.1.patch						(me, in 2.5.68-bk)
	fix overflow with large number of IRQ sources
via6103.1.patch						(Pedro A. Gracia Fajardo)
	add VIA 6103 PHY to sis900 driver
vmscan.1.patch						(Andrew Morton)
	fix vm accounting error

diff -u --exclude-from=/home/me/.exclude -r a/Makefile b/Makefile
--- a/Makefile	Sun Apr 20 06:26:50 2003
+++ b/Makefile	Tue Apr 22 04:56:49 2003
@ -1,7 +1,7 @
 VERSION = 2
 PATCHLEVEL = 5
 SUBLEVEL = 68
-EXTRAVERSION =
+EXTRAVERSION = -ce2
 
 # *DOCUMENTATION*
 # To see a list of typical targets execute "make help"
diff -u --exclude-from=/home/me/.exclude -r a/arch/i386/kernel/entry.S b/arch/i386/kernel/entry.S
--- a/arch/i386/kernel/entry.S	Sat Mar 29 09:16:32 2003
+++ b/arch/i386/kernel/entry.S	Sun Apr 20 14:29:01 2003
@ -382,10 +382,11 @
 ENTRY(interrupt)
 .text
 
+	.align 16,0x90			# make ENTRY have correct address
 vector=0
 ENTRY(irq_entries_start)
 .rept NR_IRQS
-	ALIGN
+	.align 16,0x90			# should be cacheline-aligned?
 1:	pushl $vector-256
 	jmp common_interrupt
 .data
@ -394,17 +395,18 @
 vector=vector+1
 .endr
 
-	ALIGN
+	.align 16,0x90
 common_interrupt:
 	SAVE_ALL
 	call do_IRQ
 	jmp ret_from_intr
 
 #define BUILD_INTERRUPT(name, nr)	\
+	.align 16,0x90;			\
 ENTRY(name)				\
 	pushl $nr-256;			\
 	SAVE_ALL			\
-	call smp_/**/name;	\
+	call smp_/**/name;		\
 	jmp ret_from_intr;
 
 /* The include is where all of the SMP etc. interrupts come from */
diff -u --exclude-from=/home/me/.exclude -r a/arch/i386/kernel/io_apic.c b/arch/i386/kernel/io_apic.c
--- a/arch/i386/kernel/io_apic.c	Sun Apr 20 06:26:50 2003
+++ b/arch/i386/kernel/io_apic.c	Sun Apr 20 17:41:22 2003
@ -1117,7 +1117,7 @
 	if (current_vector == SYSCALL_VECTOR)
 		goto next;
 
-	if (current_vector > FIRST_SYSTEM_VECTOR) {
+	if (current_vector >= FIRST_SYSTEM_VECTOR) {
 		offset = (offset + 1) & 7;
 		current_vector = FIRST_DEVICE_VECTOR + offset;
 	}
diff -u --exclude-from=/home/me/.exclude -r a/drivers/char/keyboard.c b/drivers/char/keyboard.c
--- a/drivers/char/keyboard.c	Tue Mar  4 22:29:17 2003
+++ b/drivers/char/keyboard.c	Sun Apr 20 14:46:11 2003
@ -601,7 +601,7 @
 		return;
 	if ((kbd->kbdmode == VC_RAW || 
 	     kbd->kbdmode == VC_MEDIUMRAW) && 
-	     value != K_SAK)
+	     value != KVAL(K_SAK))
 		return;		/* SAK is allowed even in raw mode */
 	fn_handler[value](vc, regs);
 }
diff -u --exclude-from=/home/me/.exclude -r a/drivers/ide/ide-probe.c b/drivers/ide/ide-probe.c
--- a/drivers/ide/ide-probe.c	Sun Apr 20 06:26:51 2003
+++ b/drivers/ide/ide-probe.c	Sun Apr 20 15:28:23 2003
@ -1214,7 +1214,7 @
 	spin_unlock_irq(&ide_lock);
 out_up:
 	up(&ide_cfg_sem);
-	return 0;
+	return 1;
 }
 
 static int ata_lock(dev_t dev, void *data)
diff -u --exclude-from=/home/me/.exclude -r a/drivers/isdn/tpam/tpam_queues.c b/drivers/isdn/tpam/tpam_queues.c
--- a/drivers/isdn/tpam/tpam_queues.c	Tue Mar  4 22:28:56 2003
+++ b/drivers/isdn/tpam/tpam_queues.c	Sun Apr 20 08:47:54 2003
@ -144,6 +144,7 @
 		do {
 			hpic = readl(card->bar0 + TPAM_HPIC_REGISTER);
 			if (waiting_too_long++ > 0xfffffff) {
+				kfree_skb(skb); 
 				spin_unlock(&card->lock);
 				printk(KERN_ERR "TurboPAM(tpam_irq): "
 						"waiting too long...\n");
diff -u --exclude-from=/home/me/.exclude -r a/drivers/net/sis900.c b/drivers/net/sis900.c
--- a/drivers/net/sis900.c	Sat Mar 29 09:16:22 2003
+++ b/drivers/net/sis900.c	Tue Apr 22 11:31:28 2003
@ -124,6 +124,7 @
 	{ "ICS LAN PHY",			0x0015, 0xF440, LAN },
 	{ "NS 83851 PHY",			0x2000, 0x5C20, MIX },
 	{ "Realtek RTL8201 PHY",		0x0000, 0x8200, LAN },
+	{ "VIA 6103 PHY",			0x0101, 0x8F20, LAN },
 	{0,},
 };
 
diff -u --exclude-from=/home/me/.exclude -r a/drivers/net/wan/sdla_ppp.c b/drivers/net/wan/sdla_ppp.c
--- a/drivers/net/wan/sdla_ppp.c	Sat Mar 29 09:16:22 2003
+++ b/drivers/net/wan/sdla_ppp.c	Sun Apr 20 08:47:54 2003
@ -1747,11 +1747,10 @
 					if (!test_bit(SEND_CRIT, &card->wandev.critical)){
 					 	ppp_send(card, skb->data, skb->len, htons(ETH_P_IPX));
 					}
-					dev_kfree_skb_any(skb);
-
 				} else {
 					++card->wandev.stats.rx_dropped;
 				}
+				dev_kfree_skb_any(skb);
 			} else {
 				/* Pass data up the protocol stack */
 	    			skb->dev = dev;
diff -u --exclude-from=/home/me/.exclude -r a/drivers/pci/bus.c b/drivers/pci/bus.c
--- a/drivers/pci/bus.c	Sat Mar 29 09:16:22 2003
+++ b/drivers/pci/bus.c	Sun Apr 20 11:55:24 2003
@ -75,7 +75,8 @
  * Add newly discovered PCI devices (which are on the bus->devices
  * list) to the global PCI device list, add the sysfs and procfs
  * entries.  Where a bridge is found, add the discovered bus to
- * the parents list of child buses, and recurse.
+ * the parents list of child buses, and recurse (breadth-first
+ * to be compatible with 2.4)
  *
  * Call hotplug for each new devices.
  */
@ -98,6 +99,12 @
 #endif
 		pci_create_sysfs_dev_files(dev);
 
+	}
+
+	list_for_each_entry(dev, &bus->devices, bus_list) {
+
+		BUG_ON(list_empty(&dev->global_list));
+
 		/*
 		 * If there is an unattached subordinate bus, attach
 		 * it and then scan for unattached PCI devices.
diff -u --exclude-from=/home/me/.exclude -r a/drivers/pci/probe.c b/drivers/pci/probe.c
--- a/drivers/pci/probe.c	Sat Mar 29 09:16:22 2003
+++ b/drivers/pci/probe.c	Sun Apr 20 11:55:33 2003
@ -173,7 +173,7 @
 		limit |= (io_limit_hi << 16);
 	}
 
-	if (base && base <= limit) {
+	if (base <= limit) {
 		res->flags = (io_base_lo & PCI_IO_RANGE_TYPE_MASK) | IORESOURCE_IO;
 		res->start = base;
 		res->end = limit + 0xfff;
diff -u --exclude-from=/home/me/.exclude -r a/fs/ext3/super.c b/fs/ext3/super.c
--- a/fs/ext3/super.c	Sun Apr 20 06:26:52 2003
+++ b/fs/ext3/super.c	Tue Apr 22 11:07:42 2003
@ -982,12 +982,6 @
 		return;
 	}
 
-	if (s_flags & MS_RDONLY) {
-		printk(KERN_INFO "EXT3-fs: %s: orphan cleanup on readonly fs\n",
-		       sb->s_id);
-		sb->s_flags &= ~MS_RDONLY;
-	}
-
 	if (EXT3_SB(sb)->s_mount_state & EXT3_ERROR_FS) {
 		if (es->s_last_orphan)
 			jbd_debug(1, "Errors on filesystem, "
@ -997,6 +991,12 @
 		return;
 	}
 
+	if (s_flags & MS_RDONLY) {
+		printk(KERN_INFO "EXT3-fs: %s: orphan cleanup on readonly fs\n",
+		       sb->s_id);
+		sb->s_flags &= ~MS_RDONLY;
+	}
+
 	while (es->s_last_orphan) {
 		struct inode *inode;
 
diff -u --exclude-from=/home/me/.exclude -r a/fs/fat/inode.c b/fs/fat/inode.c
--- a/fs/fat/inode.c	Sun Apr 20 06:26:23 2003
+++ b/fs/fat/inode.c	Tue Apr 22 10:57:28 2003
@ -898,6 +898,7 @
 			       sbi->fsinfo_sector);
 		} else {
 			sbi->free_clusters = CF_LE_L(fsinfo->free_clusters);
+			sbi->prev_free = CF_LE_L(fsinfo->next_cluster);
 		}
 
 		brelse(fsinfo_bh);
diff -u --exclude-from=/home/me/.exclude -r a/fs/fat/misc.c b/fs/fat/misc.c
--- a/fs/fat/misc.c	Tue Mar  4 22:29:34 2003
+++ b/fs/fat/misc.c	Tue Apr 22 10:57:28 2003
@ -74,6 +74,7 @
 		       MSDOS_SB(sb)->fsinfo_sector);
 	} else {
 		fsinfo->free_clusters = CF_LE_L(MSDOS_SB(sb)->free_clusters);
+		fsinfo->next_cluster = CF_LE_L(MSDOS_SB(sb)->prev_free);
 		mark_buffer_dirty(bh);
 	}
 	brelse(bh);
diff -u --exclude-from=/home/me/.exclude -r a/include/linux/msdos_fs.h b/include/linux/msdos_fs.h
--- a/include/linux/msdos_fs.h	Tue Mar  4 22:29:33 2003
+++ b/include/linux/msdos_fs.h	Tue Apr 22 10:57:28 2003
@ -146,8 +146,7 @
 	__u32   reserved1[120];	/* Nothing as far as I can tell */
 	__u32   signature2;	/* 0x61417272L */
 	__u32   free_clusters;	/* Free cluster count.  -1 if unknown */
-	__u32   next_cluster;	/* Most recently allocated cluster.
-				 * Unused under Linux. */
+	__u32   next_cluster;	/* Most recently allocated cluster */
 	__u32   reserved2[4];
 };
 
diff -u --exclude-from=/home/me/.exclude -r a/mm/vmscan.c b/mm/vmscan.c
--- a/mm/vmscan.c	Sun Apr 20 06:26:52 2003
+++ b/mm/vmscan.c	Tue Apr 22 05:37:51 2003
@ -558,6 +558,7 @
 refill_inactive_zone(struct zone *zone, const int nr_pages_in,
 			struct page_state *ps, int priority)
 {
+	int pgmoved;
 	int pgdeactivate = 0;
 	int nr_pages = nr_pages_in;
 	LIST_HEAD(l_hold);	/* The pages which were snipped off */
@ -571,6 +572,7 @
 	long swap_tendency;
 
 	lru_add_drain();
+	pgmoved = 0;
 	spin_lock_irq(&zone->lru_lock);
 	while (nr_pages && !list_empty(&zone->active_list)) {
 		page = list_entry(zone->active_list.prev, struct page, lru);
@ -585,9 +587,12 @
 		} else {
 			page_cache_get(page);
 			list_add(&page->lru, &l_hold);
+			pgmoved++;
 		}
 		nr_pages--;
 	}
+	zone->nr_active   -= pgmoved;
+	zone->nr_inactive += pgmoved;
 	spin_unlock_irq(&zone->lru_lock);
 
 	/*
@ -647,10 +652,10 @
 			continue;
 		}
 		list_add(&page->lru, &l_inactive);
-		pgdeactivate++;
 	}
 
 	pagevec_init(&pvec, 1);
+	pgmoved = 0;
 	spin_lock_irq(&zone->lru_lock);
 	while (!list_empty(&l_inactive)) {
 		page = list_entry(l_inactive.prev, struct page, lru);
@ -660,19 +665,27 @
 		if (!TestClearPageActive(page))
 			BUG();
 		list_move(&page->lru, &zone->inactive_list);
+		pgmoved++;
 		if (!pagevec_add(&pvec, page)) {
+			zone->nr_inactive += pgmoved;
 			spin_unlock_irq(&zone->lru_lock);
+			pgdeactivate += pgmoved;
+			pgmoved = 0;
 			if (buffer_heads_over_limit)
 				pagevec_strip(&pvec);
 			__pagevec_release(&pvec);
 			spin_lock_irq(&zone->lru_lock);
 		}
 	}
+	zone->nr_inactive += pgmoved;
+	pgdeactivate += pgmoved;
 	if (buffer_heads_over_limit) {
 		spin_unlock_irq(&zone->lru_lock);
 		pagevec_strip(&pvec);
 		spin_lock_irq(&zone->lru_lock);
 	}
+
+	pgmoved = 0;
 	while (!list_empty(&l_active)) {
 		page = list_entry(l_active.prev, struct page, lru);
 		prefetchw_prev_lru_page(page, &l_active, flags);
@ -680,14 +693,16 @
 			BUG();
 		BUG_ON(!PageActive(page));
 		list_move(&page->lru, &zone->active_list);
+		pgmoved++;
 		if (!pagevec_add(&pvec, page)) {
+			zone->nr_active += pgmoved;
+			pgmoved = 0;
 			spin_unlock_irq(&zone->lru_lock);
 			__pagevec_release(&pvec);
 			spin_lock_irq(&zone->lru_lock);
 		}
 	}
-	zone->nr_active -= pgdeactivate;
-	zone->nr_inactive += pgdeactivate;
+	zone->nr_active += pgmoved;
 	spin_unlock_irq(&zone->lru_lock);
 	pagevec_release(&pvec);
 
diff -u --exclude-from=/home/me/.exclude -r a/net/ax25/af_ax25.c b/net/ax25/af_ax25.c
--- a/net/ax25/af_ax25.c	Sat Mar 29 09:16:22 2003
+++ b/net/ax25/af_ax25.c	Sun Apr 20 08:47:54 2003
@ -1202,6 +1202,8 @
 		ax25_insert_socket(ax25);
 	} else {
 		if (ax25->ax25_dev == NULL) {
+			if (digi != NULL)
+				kfree(digi);
 			err = -EHOSTUNREACH;
 			goto out;
 		}
diff -u --exclude-from=/home/me/.exclude -r a/net/ipv4/netfilter/ip_queue.c b/net/ipv4/netfilter/ip_queue.c
--- a/net/ipv4/netfilter/ip_queue.c	Sun Apr 20 06:26:24 2003
+++ b/net/ipv4/netfilter/ip_queue.c	Sun Apr 20 08:47:54 2003
@ -298,10 +298,11 @
 		goto err_out_free;
 		
 	write_lock_bh(&queue_lock);
-	
+
 	if (!peer_pid)
-		goto err_out_unlock;
+		goto err_out_free_nskb; 
 
+	/* netlink_unicast will either free the nskb or attach it to a socket */ 
 	status = netlink_unicast(ipqnl, nskb, peer_pid, MSG_DONTWAIT);
 	if (status < 0)
 		goto err_out_unlock;
@ -312,6 +313,9 @
 
 	write_unlock_bh(&queue_lock);
 	return status;
+
+err_out_free_nskb:
+	kfree_skb(nskb); 
 	
 err_out_unlock:
 	write_unlock_bh(&queue_lock);
diff -u --exclude-from=/home/me/.exclude -r a/net/ipv6/netfilter/ip6_queue.c b/net/ipv6/netfilter/ip6_queue.c
--- a/net/ipv6/netfilter/ip6_queue.c	Sun Apr 20 06:26:24 2003
+++ b/net/ipv6/netfilter/ip6_queue.c	Sun Apr 20 08:47:54 2003
@ -304,8 +304,9 @
 	write_lock_bh(&queue_lock);
 	
 	if (!peer_pid)
-		goto err_out_unlock;
+		goto err_out_free_nskb; 
 
+ 	/* netlink_unicast will either free the nskb or attach it to a socket */ 
 	status = netlink_unicast(ipqnl, nskb, peer_pid, MSG_DONTWAIT);
 	if (status < 0)
 		goto err_out_unlock;
@ -317,6 +318,9 @
 	write_unlock_bh(&queue_lock);
 	return status;
 	
+err_out_free_nskb:
+	kfree_skb(nskb); 
+	
 err_out_unlock:
 	write_unlock_bh(&queue_lock);
 
diff -u --exclude-from=/home/me/.exclude -r a/net/irda/irttp.c b/net/irda/irttp.c
--- a/net/irda/irttp.c	Tue Mar  4 22:29:23 2003
+++ b/net/irda/irttp.c	Sun Apr 20 08:47:54 2003
@ -263,7 +263,7 @
 
 	IRDA_DEBUG(2, "%s(), rx_sdu_size=%d\n",  __FUNCTION__,
 		   self->rx_sdu_size);
-	ASSERT(n <= self->rx_sdu_size, return NULL;);
+	ASSERT(n <= self->rx_sdu_size, {dev_kfree_skb(skb); return NULL;});
 
 	/* Set the new length */
 	skb_trim(skb, n);


------
 Chuck