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-rw-r--r--arch/ia64/sn/kernel/sn2/Makefile2
-rw-r--r--arch/ia64/sn/kernel/sn2/prominfo_proc.c25
-rw-r--r--arch/ia64/sn/kernel/sn2/sn2_smp.c213
-rw-r--r--arch/ia64/sn/kernel/sn2/sn_hwperf.c5
-rw-r--r--arch/ia64/sn/kernel/sn2/sn_proc_fs.c22
-rw-r--r--arch/ia64/sn/kernel/sn2/timer.c19
-rw-r--r--arch/ia64/sn/kernel/sn2/timer_interrupt.c7
7 files changed, 133 insertions, 160 deletions
diff --git a/arch/ia64/sn/kernel/sn2/Makefile b/arch/ia64/sn/kernel/sn2/Makefile
index 170bde4549d..99e17769323 100644
--- a/arch/ia64/sn/kernel/sn2/Makefile
+++ b/arch/ia64/sn/kernel/sn2/Makefile
@@ -9,5 +9,7 @@
# sn2 specific kernel files
#
+CPPFLAGS += -I$(srctree)/arch/ia64/sn/include
+
obj-y += cache.o io.o ptc_deadlock.o sn2_smp.o sn_proc_fs.o \
prominfo_proc.o timer.o timer_interrupt.o sn_hwperf.o
diff --git a/arch/ia64/sn/kernel/sn2/prominfo_proc.c b/arch/ia64/sn/kernel/sn2/prominfo_proc.c
index 81c63b2f8ae..6ae276d5d50 100644
--- a/arch/ia64/sn/kernel/sn2/prominfo_proc.c
+++ b/arch/ia64/sn/kernel/sn2/prominfo_proc.c
@@ -3,7 +3,7 @@
* License. See the file "COPYING" in the main directory of this archive
* for more details.
*
- * Copyright (C) 1999,2001-2004 Silicon Graphics, Inc. All Rights Reserved.
+ * Copyright (C) 1999,2001-2004, 2006 Silicon Graphics, Inc. All Rights Reserved.
*
* Module to export the system's Firmware Interface Tables, including
* PROM revision numbers and banners, in /proc
@@ -190,7 +190,7 @@ static int
read_version_entry(char *page, char **start, off_t off, int count, int *eof,
void *data)
{
- int len = 0;
+ int len;
/* data holds the NASID of the node */
len = dump_version(page, (unsigned long)data);
@@ -202,7 +202,7 @@ static int
read_fit_entry(char *page, char **start, off_t off, int count, int *eof,
void *data)
{
- int len = 0;
+ int len;
/* data holds the NASID of the node */
len = dump_fit(page, (unsigned long)data);
@@ -229,13 +229,16 @@ int __init prominfo_init(void)
struct proc_dir_entry *p;
cnodeid_t cnodeid;
unsigned long nasid;
+ int size;
char name[NODE_NAME_LEN];
if (!ia64_platform_is("sn2"))
return 0;
- proc_entries = kmalloc(num_online_nodes() * sizeof(struct proc_dir_entry *),
- GFP_KERNEL);
+ size = num_online_nodes() * sizeof(struct proc_dir_entry *);
+ proc_entries = kzalloc(size, GFP_KERNEL);
+ if (!proc_entries)
+ return -ENOMEM;
sgi_prominfo_entry = proc_mkdir("sgi_prominfo", NULL);
@@ -244,14 +247,12 @@ int __init prominfo_init(void)
sprintf(name, "node%d", cnodeid);
*entp = proc_mkdir(name, sgi_prominfo_entry);
nasid = cnodeid_to_nasid(cnodeid);
- p = create_proc_read_entry(
- "fit", 0, *entp, read_fit_entry,
- (void *)nasid);
+ p = create_proc_read_entry("fit", 0, *entp, read_fit_entry,
+ (void *)nasid);
if (p)
p->owner = THIS_MODULE;
- p = create_proc_read_entry(
- "version", 0, *entp, read_version_entry,
- (void *)nasid);
+ p = create_proc_read_entry("version", 0, *entp,
+ read_version_entry, (void *)nasid);
if (p)
p->owner = THIS_MODULE;
entp++;
@@ -263,7 +264,7 @@ int __init prominfo_init(void)
void __exit prominfo_exit(void)
{
struct proc_dir_entry **entp;
- unsigned cnodeid;
+ unsigned int cnodeid;
char name[NODE_NAME_LEN];
entp = proc_entries;
diff --git a/arch/ia64/sn/kernel/sn2/sn2_smp.c b/arch/ia64/sn/kernel/sn2/sn2_smp.c
index 471bbaa65d1..b2e1e746b47 100644
--- a/arch/ia64/sn/kernel/sn2/sn2_smp.c
+++ b/arch/ia64/sn/kernel/sn2/sn2_smp.c
@@ -5,7 +5,7 @@
* License. See the file "COPYING" in the main directory of this archive
* for more details.
*
- * Copyright (C) 2000-2005 Silicon Graphics, Inc. All rights reserved.
+ * Copyright (C) 2000-2006 Silicon Graphics, Inc. All rights reserved.
*/
#include <linux/init.h>
@@ -46,104 +46,24 @@ DECLARE_PER_CPU(struct ptc_stats, ptcstats);
static __cacheline_aligned DEFINE_SPINLOCK(sn2_global_ptc_lock);
-void sn2_ptc_deadlock_recovery(short *, short, int, volatile unsigned long *, unsigned long data0,
- volatile unsigned long *, unsigned long data1);
+extern unsigned long
+sn2_ptc_deadlock_recovery_core(volatile unsigned long *, unsigned long,
+ volatile unsigned long *, unsigned long,
+ volatile unsigned long *, unsigned long);
+void
+sn2_ptc_deadlock_recovery(short *, short, short, int,
+ volatile unsigned long *, unsigned long,
+ volatile unsigned long *, unsigned long);
-#ifdef DEBUG_PTC
/*
- * ptctest:
- *
- * xyz - 3 digit hex number:
- * x - Force PTC purges to use shub:
- * 0 - no force
- * 1 - force
- * y - interupt enable
- * 0 - disable interrupts
- * 1 - leave interuupts enabled
- * z - type of lock:
- * 0 - global lock
- * 1 - node local lock
- * 2 - no lock
- *
- * Note: on shub1, only ptctest == 0 is supported. Don't try other values!
+ * Note: some is the following is captured here to make degugging easier
+ * (the macros make more sense if you see the debug patch - not posted)
*/
-
-static unsigned int sn2_ptctest = 0;
-
-static int __init ptc_test(char *str)
-{
- get_option(&str, &sn2_ptctest);
- return 1;
-}
-__setup("ptctest=", ptc_test);
-
-static inline int ptc_lock(unsigned long *flagp)
-{
- unsigned long opt = sn2_ptctest & 255;
-
- switch (opt) {
- case 0x00:
- spin_lock_irqsave(&sn2_global_ptc_lock, *flagp);
- break;
- case 0x01:
- spin_lock_irqsave(&sn_nodepda->ptc_lock, *flagp);
- break;
- case 0x02:
- local_irq_save(*flagp);
- break;
- case 0x10:
- spin_lock(&sn2_global_ptc_lock);
- break;
- case 0x11:
- spin_lock(&sn_nodepda->ptc_lock);
- break;
- case 0x12:
- break;
- default:
- BUG();
- }
- return opt;
-}
-
-static inline void ptc_unlock(unsigned long flags, int opt)
-{
- switch (opt) {
- case 0x00:
- spin_unlock_irqrestore(&sn2_global_ptc_lock, flags);
- break;
- case 0x01:
- spin_unlock_irqrestore(&sn_nodepda->ptc_lock, flags);
- break;
- case 0x02:
- local_irq_restore(flags);
- break;
- case 0x10:
- spin_unlock(&sn2_global_ptc_lock);
- break;
- case 0x11:
- spin_unlock(&sn_nodepda->ptc_lock);
- break;
- case 0x12:
- break;
- default:
- BUG();
- }
-}
-#else
-
#define sn2_ptctest 0
-
-static inline int ptc_lock(unsigned long *flagp)
-{
- spin_lock_irqsave(&sn2_global_ptc_lock, *flagp);
- return 0;
-}
-
-static inline void ptc_unlock(unsigned long flags, int opt)
-{
- spin_unlock_irqrestore(&sn2_global_ptc_lock, flags);
-}
-#endif
+#define local_node_uses_ptc_ga(sh1) ((sh1) ? 1 : 0)
+#define max_active_pio(sh1) ((sh1) ? 32 : 7)
+#define reset_max_active_on_deadlock() 1
+#define PTC_LOCK(sh1) ((sh1) ? &sn2_global_ptc_lock : &sn_nodepda->ptc_lock)
struct ptc_stats {
unsigned long ptc_l;
@@ -151,27 +71,32 @@ struct ptc_stats {
unsigned long shub_ptc_flushes;
unsigned long nodes_flushed;
unsigned long deadlocks;
+ unsigned long deadlocks2;
unsigned long lock_itc_clocks;
unsigned long shub_itc_clocks;
unsigned long shub_itc_clocks_max;
+ unsigned long shub_ptc_flushes_not_my_mm;
};
+#define sn2_ptctest 0
+
static inline unsigned long wait_piowc(void)
{
- volatile unsigned long *piows, zeroval;
- unsigned long ws;
+ volatile unsigned long *piows;
+ unsigned long zeroval, ws;
piows = pda->pio_write_status_addr;
zeroval = pda->pio_write_status_val;
do {
cpu_relax();
} while (((ws = *piows) & SH_PIO_WRITE_STATUS_PENDING_WRITE_COUNT_MASK) != zeroval);
- return ws;
+ return (ws & SH_PIO_WRITE_STATUS_WRITE_DEADLOCK_MASK) != 0;
}
void sn_tlb_migrate_finish(struct mm_struct *mm)
{
- if (mm == current->mm)
+ /* flush_tlb_mm is inefficient if more than 1 users of mm */
+ if (mm == current->mm && mm && atomic_read(&mm->mm_users) == 1)
flush_tlb_mm(mm);
}
@@ -201,12 +126,14 @@ void
sn2_global_tlb_purge(struct mm_struct *mm, unsigned long start,
unsigned long end, unsigned long nbits)
{
- int i, opt, shub1, cnode, mynasid, cpu, lcpu = 0, nasid, flushed = 0;
- int mymm = (mm == current->active_mm && current->mm);
+ int i, ibegin, shub1, cnode, mynasid, cpu, lcpu = 0, nasid;
+ int mymm = (mm == current->active_mm && mm == current->mm);
+ int use_cpu_ptcga;
volatile unsigned long *ptc0, *ptc1;
- unsigned long itc, itc2, flags, data0 = 0, data1 = 0, rr_value;
+ unsigned long itc, itc2, flags, data0 = 0, data1 = 0, rr_value, old_rr = 0;
short nasids[MAX_NUMNODES], nix;
nodemask_t nodes_flushed;
+ int active, max_active, deadlock;
nodes_clear(nodes_flushed);
i = 0;
@@ -267,41 +194,56 @@ sn2_global_tlb_purge(struct mm_struct *mm, unsigned long start,
mynasid = get_nasid();
+ use_cpu_ptcga = local_node_uses_ptc_ga(shub1);
+ max_active = max_active_pio(shub1);
itc = ia64_get_itc();
- opt = ptc_lock(&flags);
+ spin_lock_irqsave(PTC_LOCK(shub1), flags);
itc2 = ia64_get_itc();
+
__get_cpu_var(ptcstats).lock_itc_clocks += itc2 - itc;
__get_cpu_var(ptcstats).shub_ptc_flushes++;
__get_cpu_var(ptcstats).nodes_flushed += nix;
+ if (!mymm)
+ __get_cpu_var(ptcstats).shub_ptc_flushes_not_my_mm++;
+ if (use_cpu_ptcga && !mymm) {
+ old_rr = ia64_get_rr(start);
+ ia64_set_rr(start, (old_rr & 0xff) | (rr_value << 8));
+ ia64_srlz_d();
+ }
+
+ wait_piowc();
do {
if (shub1)
data1 = start | (1UL << SH1_PTC_1_START_SHFT);
else
data0 = (data0 & ~SH2_PTC_ADDR_MASK) | (start & SH2_PTC_ADDR_MASK);
- for (i = 0; i < nix; i++) {
+ deadlock = 0;
+ active = 0;
+ for (ibegin = 0, i = 0; i < nix; i++) {
nasid = nasids[i];
- if ((!(sn2_ptctest & 3)) && unlikely(nasid == mynasid && mymm)) {
+ if (use_cpu_ptcga && unlikely(nasid == mynasid)) {
ia64_ptcga(start, nbits << 2);
ia64_srlz_i();
} else {
ptc0 = CHANGE_NASID(nasid, ptc0);
if (ptc1)
ptc1 = CHANGE_NASID(nasid, ptc1);
- pio_atomic_phys_write_mmrs(ptc0, data0, ptc1,
- data1);
- flushed = 1;
+ pio_atomic_phys_write_mmrs(ptc0, data0, ptc1, data1);
+ active++;
+ }
+ if (active >= max_active || i == (nix - 1)) {
+ if ((deadlock = wait_piowc())) {
+ sn2_ptc_deadlock_recovery(nasids, ibegin, i, mynasid, ptc0, data0, ptc1, data1);
+ if (reset_max_active_on_deadlock())
+ max_active = 1;
+ }
+ active = 0;
+ ibegin = i + 1;
}
}
- if (flushed
- && (wait_piowc() &
- (SH_PIO_WRITE_STATUS_WRITE_DEADLOCK_MASK))) {
- sn2_ptc_deadlock_recovery(nasids, nix, mynasid, ptc0, data0, ptc1, data1);
- }
-
start += (1UL << nbits);
-
} while (start < end);
itc2 = ia64_get_itc() - itc2;
@@ -309,7 +251,12 @@ sn2_global_tlb_purge(struct mm_struct *mm, unsigned long start,
if (itc2 > __get_cpu_var(ptcstats).shub_itc_clocks_max)
__get_cpu_var(ptcstats).shub_itc_clocks_max = itc2;
- ptc_unlock(flags, opt);
+ if (old_rr) {
+ ia64_set_rr(start, old_rr);
+ ia64_srlz_d();
+ }
+
+ spin_unlock_irqrestore(PTC_LOCK(shub1), flags);
preempt_enable();
}
@@ -321,27 +268,31 @@ sn2_global_tlb_purge(struct mm_struct *mm, unsigned long start,
* TLB flush transaction. The recovery sequence is somewhat tricky & is
* coded in assembly language.
*/
-void sn2_ptc_deadlock_recovery(short *nasids, short nix, int mynasid, volatile unsigned long *ptc0, unsigned long data0,
- volatile unsigned long *ptc1, unsigned long data1)
+
+void
+sn2_ptc_deadlock_recovery(short *nasids, short ib, short ie, int mynasid,
+ volatile unsigned long *ptc0, unsigned long data0,
+ volatile unsigned long *ptc1, unsigned long data1)
{
- extern void sn2_ptc_deadlock_recovery_core(volatile unsigned long *, unsigned long,
- volatile unsigned long *, unsigned long, volatile unsigned long *, unsigned long);
short nasid, i;
- unsigned long *piows, zeroval;
+ unsigned long *piows, zeroval, n;
__get_cpu_var(ptcstats).deadlocks++;
piows = (unsigned long *) pda->pio_write_status_addr;
zeroval = pda->pio_write_status_val;
- for (i=0; i < nix; i++) {
+
+ for (i=ib; i <= ie; i++) {
nasid = nasids[i];
- if (!(sn2_ptctest & 3) && nasid == mynasid)
+ if (local_node_uses_ptc_ga(is_shub1()) && nasid == mynasid)
continue;
ptc0 = CHANGE_NASID(nasid, ptc0);
if (ptc1)
ptc1 = CHANGE_NASID(nasid, ptc1);
- sn2_ptc_deadlock_recovery_core(ptc0, data0, ptc1, data1, piows, zeroval);
+
+ n = sn2_ptc_deadlock_recovery_core(ptc0, data0, ptc1, data1, piows, zeroval);
+ __get_cpu_var(ptcstats).deadlocks2 += n;
}
}
@@ -452,20 +403,22 @@ static int sn2_ptc_seq_show(struct seq_file *file, void *data)
cpu = *(loff_t *) data;
if (!cpu) {
- seq_printf(file, "# ptc_l change_rid shub_ptc_flushes shub_nodes_flushed deadlocks lock_nsec shub_nsec shub_nsec_max\n");
+ seq_printf(file,
+ "# cpu ptc_l newrid ptc_flushes nodes_flushed deadlocks lock_nsec shub_nsec shub_nsec_max not_my_mm deadlock2\n");
seq_printf(file, "# ptctest %d\n", sn2_ptctest);
}
if (cpu < NR_CPUS && cpu_online(cpu)) {
stat = &per_cpu(ptcstats, cpu);
- seq_printf(file, "cpu %d %ld %ld %ld %ld %ld %ld %ld %ld\n", cpu, stat->ptc_l,
+ seq_printf(file, "cpu %d %ld %ld %ld %ld %ld %ld %ld %ld %ld %ld\n", cpu, stat->ptc_l,
stat->change_rid, stat->shub_ptc_flushes, stat->nodes_flushed,
stat->deadlocks,
1000 * stat->lock_itc_clocks / per_cpu(cpu_info, cpu).cyc_per_usec,
1000 * stat->shub_itc_clocks / per_cpu(cpu_info, cpu).cyc_per_usec,
- 1000 * stat->shub_itc_clocks_max / per_cpu(cpu_info, cpu).cyc_per_usec);
+ 1000 * stat->shub_itc_clocks_max / per_cpu(cpu_info, cpu).cyc_per_usec,
+ stat->shub_ptc_flushes_not_my_mm,
+ stat->deadlocks2);
}
-
return 0;
}
@@ -476,7 +429,7 @@ static struct seq_operations sn2_ptc_seq_ops = {
.show = sn2_ptc_seq_show
};
-int sn2_ptc_proc_open(struct inode *inode, struct file *file)
+static int sn2_ptc_proc_open(struct inode *inode, struct file *file)
{
return seq_open(file, &sn2_ptc_seq_ops);
}
@@ -493,7 +446,7 @@ static struct proc_dir_entry *proc_sn2_ptc;
static int __init sn2_ptc_init(void)
{
if (!ia64_platform_is("sn2"))
- return -ENOSYS;
+ return 0;
if (!(proc_sn2_ptc = create_proc_entry(PTC_BASENAME, 0444, NULL))) {
printk(KERN_ERR "unable to create %s proc entry", PTC_BASENAME);
diff --git a/arch/ia64/sn/kernel/sn2/sn_hwperf.c b/arch/ia64/sn/kernel/sn2/sn_hwperf.c
index 19b54fbcd7e..70db21f3df2 100644
--- a/arch/ia64/sn/kernel/sn2/sn_hwperf.c
+++ b/arch/ia64/sn/kernel/sn2/sn_hwperf.c
@@ -3,7 +3,7 @@
* License. See the file "COPYING" in the main directory of this archive
* for more details.
*
- * Copyright (C) 2004-2005 Silicon Graphics, Inc. All rights reserved.
+ * Copyright (C) 2004-2006 Silicon Graphics, Inc. All rights reserved.
*
* SGI Altix topology and hardware performance monitoring API.
* Mark Goodwin <markgw@sgi.com>.
@@ -973,6 +973,9 @@ static int __devinit sn_hwperf_misc_register_init(void)
{
int e;
+ if (!ia64_platform_is("sn2"))
+ return 0;
+
sn_hwperf_init();
/*
diff --git a/arch/ia64/sn/kernel/sn2/sn_proc_fs.c b/arch/ia64/sn/kernel/sn2/sn_proc_fs.c
index a06719d752a..c686d9c12f7 100644
--- a/arch/ia64/sn/kernel/sn2/sn_proc_fs.c
+++ b/arch/ia64/sn/kernel/sn2/sn_proc_fs.c
@@ -6,11 +6,11 @@
* Copyright (C) 2000-2005 Silicon Graphics, Inc. All rights reserved.
*/
#include <linux/config.h>
-#include <asm/uaccess.h>
#ifdef CONFIG_PROC_FS
#include <linux/proc_fs.h>
#include <linux/seq_file.h>
+#include <asm/uaccess.h>
#include <asm/sn/sn_sal.h>
static int partition_id_show(struct seq_file *s, void *p)
@@ -90,10 +90,10 @@ static int coherence_id_open(struct inode *inode, struct file *file)
return single_open(file, coherence_id_show, NULL);
}
-static struct proc_dir_entry *sn_procfs_create_entry(
- const char *name, struct proc_dir_entry *parent,
- int (*openfunc)(struct inode *, struct file *),
- int (*releasefunc)(struct inode *, struct file *))
+static struct proc_dir_entry
+*sn_procfs_create_entry(const char *name, struct proc_dir_entry *parent,
+ int (*openfunc)(struct inode *, struct file *),
+ int (*releasefunc)(struct inode *, struct file *))
{
struct proc_dir_entry *e = create_proc_entry(name, 0444, parent);
@@ -126,24 +126,24 @@ void register_sn_procfs(void)
return;
sn_procfs_create_entry("partition_id", sgi_proc_dir,
- partition_id_open, single_release);
+ partition_id_open, single_release);
sn_procfs_create_entry("system_serial_number", sgi_proc_dir,
- system_serial_number_open, single_release);
+ system_serial_number_open, single_release);
sn_procfs_create_entry("licenseID", sgi_proc_dir,
- licenseID_open, single_release);
+ licenseID_open, single_release);
e = sn_procfs_create_entry("sn_force_interrupt", sgi_proc_dir,
- sn_force_interrupt_open, single_release);
+ sn_force_interrupt_open, single_release);
if (e)
e->proc_fops->write = sn_force_interrupt_write_proc;
sn_procfs_create_entry("coherence_id", sgi_proc_dir,
- coherence_id_open, single_release);
+ coherence_id_open, single_release);
sn_procfs_create_entry("sn_topology", sgi_proc_dir,
- sn_topology_open, sn_topology_release);
+ sn_topology_open, sn_topology_release);
}
#endif /* CONFIG_PROC_FS */
diff --git a/arch/ia64/sn/kernel/sn2/timer.c b/arch/ia64/sn/kernel/sn2/timer.c
index deb9baf4d47..56a88b6df4b 100644
--- a/arch/ia64/sn/kernel/sn2/timer.c
+++ b/arch/ia64/sn/kernel/sn2/timer.c
@@ -14,6 +14,7 @@
#include <asm/hw_irq.h>
#include <asm/system.h>
+#include <asm/timex.h>
#include <asm/sn/leds.h>
#include <asm/sn/shub_mmr.h>
@@ -28,9 +29,27 @@ static struct time_interpolator sn2_interpolator = {
.source = TIME_SOURCE_MMIO64
};
+/*
+ * sn udelay uses the RTC instead of the ITC because the ITC is not
+ * synchronized across all CPUs, and the thread may migrate to another CPU
+ * if preemption is enabled.
+ */
+static void
+ia64_sn_udelay (unsigned long usecs)
+{
+ unsigned long start = rtc_time();
+ unsigned long end = start +
+ usecs * sn_rtc_cycles_per_second / 1000000;
+
+ while (time_before((unsigned long)rtc_time(), end))
+ cpu_relax();
+}
+
void __init sn_timer_init(void)
{
sn2_interpolator.frequency = sn_rtc_cycles_per_second;
sn2_interpolator.addr = RTC_COUNTER_ADDR;
register_time_interpolator(&sn2_interpolator);
+
+ ia64_udelay = &ia64_sn_udelay;
}
diff --git a/arch/ia64/sn/kernel/sn2/timer_interrupt.c b/arch/ia64/sn/kernel/sn2/timer_interrupt.c
index adf5db2e2af..fa7f6994591 100644
--- a/arch/ia64/sn/kernel/sn2/timer_interrupt.c
+++ b/arch/ia64/sn/kernel/sn2/timer_interrupt.c
@@ -1,7 +1,7 @@
/*
*
*
- * Copyright (c) 2005 Silicon Graphics, Inc. All Rights Reserved.
+ * Copyright (c) 2005, 2006 Silicon Graphics, Inc. All Rights Reserved.
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of version 2 of the GNU General Public License
@@ -22,11 +22,6 @@
* License along with this program; if not, write the Free Software
* Foundation, Inc., 59 Temple Place - Suite 330, Boston MA 02111-1307, USA.
*
- * Contact information: Silicon Graphics, Inc., 1600 Amphitheatre Pkwy,
- * Mountain View, CA 94043, or:
- *
- * http://www.sgi.com
- *
* For further information regarding this notice, see:
*
* http://oss.sgi.com/projects/GenInfo/NoticeExplan