From 3be44b9cc33d26930cb3bb014f35f582c6522481 Mon Sep 17 00:00:00 2001 From: Jack Steiner Date: Tue, 8 May 2007 14:50:43 -0700 Subject: [IA64] Optional method to purge the TLB on SN systems This patch adds an optional method for purging the TLB on SN IA64 systems. The change should not affect any non-SN system. Signed-off-by: Jack Steiner Signed-off-by: Tony Luck --- arch/ia64/sn/kernel/sn2/sn2_smp.c | 65 ++++++++++++++++++++++++++++++++++++--- 1 file changed, 60 insertions(+), 5 deletions(-) (limited to 'arch/ia64/sn/kernel/sn2/sn2_smp.c') diff --git a/arch/ia64/sn/kernel/sn2/sn2_smp.c b/arch/ia64/sn/kernel/sn2/sn2_smp.c index 601747b1e22..5d318b579fb 100644 --- a/arch/ia64/sn/kernel/sn2/sn2_smp.c +++ b/arch/ia64/sn/kernel/sn2/sn2_smp.c @@ -46,6 +46,9 @@ DECLARE_PER_CPU(struct ptc_stats, ptcstats); static __cacheline_aligned DEFINE_SPINLOCK(sn2_global_ptc_lock); +/* 0 = old algorithm (no IPI flushes), 1 = ipi deadlock flush, 2 = ipi instead of SHUB ptc, >2 = always ipi */ +static int sn2_flush_opt = 0; + extern unsigned long sn2_ptc_deadlock_recovery_core(volatile unsigned long *, unsigned long, volatile unsigned long *, unsigned long, @@ -76,6 +79,8 @@ struct ptc_stats { unsigned long shub_itc_clocks; unsigned long shub_itc_clocks_max; unsigned long shub_ptc_flushes_not_my_mm; + unsigned long shub_ipi_flushes; + unsigned long shub_ipi_flushes_itc_clocks; }; #define sn2_ptctest 0 @@ -121,6 +126,18 @@ void sn_tlb_migrate_finish(struct mm_struct *mm) flush_tlb_mm(mm); } +static void +sn2_ipi_flush_all_tlb(struct mm_struct *mm) +{ + unsigned long itc; + + itc = ia64_get_itc(); + smp_flush_tlb_cpumask(mm->cpu_vm_mask); + itc = ia64_get_itc() - itc; + __get_cpu_var(ptcstats).shub_ipi_flushes_itc_clocks += itc; + __get_cpu_var(ptcstats).shub_ipi_flushes++; +} + /** * sn2_global_tlb_purge - globally purge translation cache of virtual address range * @mm: mm_struct containing virtual address range @@ -154,7 +171,12 @@ sn2_global_tlb_purge(struct mm_struct *mm, unsigned long start, 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; + int active, max_active, deadlock, flush_opt = sn2_flush_opt; + + if (flush_opt > 2) { + sn2_ipi_flush_all_tlb(mm); + return; + } nodes_clear(nodes_flushed); i = 0; @@ -189,6 +211,12 @@ sn2_global_tlb_purge(struct mm_struct *mm, unsigned long start, return; } + if (flush_opt == 2) { + sn2_ipi_flush_all_tlb(mm); + preempt_enable(); + return; + } + itc = ia64_get_itc(); nix = 0; for_each_node_mask(cnode, nodes_flushed) @@ -256,6 +284,8 @@ sn2_global_tlb_purge(struct mm_struct *mm, unsigned long start, } if (active >= max_active || i == (nix - 1)) { if ((deadlock = wait_piowc())) { + if (flush_opt == 1) + goto done; sn2_ptc_deadlock_recovery(nasids, ibegin, i, mynasid, ptc0, data0, ptc1, data1); if (reset_max_active_on_deadlock()) max_active = 1; @@ -267,6 +297,7 @@ sn2_global_tlb_purge(struct mm_struct *mm, unsigned long start, start += (1UL << nbits); } while (start < end); +done: itc2 = ia64_get_itc() - itc2; __get_cpu_var(ptcstats).shub_itc_clocks += itc2; if (itc2 > __get_cpu_var(ptcstats).shub_itc_clocks_max) @@ -279,6 +310,11 @@ sn2_global_tlb_purge(struct mm_struct *mm, unsigned long start, spin_unlock_irqrestore(PTC_LOCK(shub1), flags); + if (flush_opt == 1 && deadlock) { + __get_cpu_var(ptcstats).deadlocks++; + sn2_ipi_flush_all_tlb(mm); + } + preempt_enable(); } @@ -425,24 +461,42 @@ static int sn2_ptc_seq_show(struct seq_file *file, void *data) if (!cpu) { 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); + "# cpu ptc_l newrid ptc_flushes nodes_flushed deadlocks lock_nsec shub_nsec shub_nsec_max not_my_mm deadlock2 ipi_fluches ipi_nsec\n"); + seq_printf(file, "# ptctest %d, flushopt %d\n", sn2_ptctest, sn2_flush_opt); } 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 %ld %ld\n", cpu, stat->ptc_l, + seq_printf(file, "cpu %d %ld %ld %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, stat->shub_ptc_flushes_not_my_mm, - stat->deadlocks2); + stat->deadlocks2, + stat->shub_ipi_flushes, + 1000 * stat->shub_ipi_flushes_itc_clocks / per_cpu(cpu_info, cpu).cyc_per_usec); } return 0; } +static ssize_t sn2_ptc_proc_write(struct file *file, const char __user *user, size_t count, loff_t *data) +{ + int cpu; + char optstr[64]; + + if (copy_from_user(optstr, user, count)) + return -EFAULT; + optstr[count - 1] = '\0'; + sn2_flush_opt = simple_strtoul(optstr, NULL, 0); + + for_each_online_cpu(cpu) + memset(&per_cpu(ptcstats, cpu), 0, sizeof(struct ptc_stats)); + + return count; +} + static struct seq_operations sn2_ptc_seq_ops = { .start = sn2_ptc_seq_start, .next = sn2_ptc_seq_next, @@ -458,6 +512,7 @@ static int sn2_ptc_proc_open(struct inode *inode, struct file *file) static const struct file_operations proc_sn2_ptc_operations = { .open = sn2_ptc_proc_open, .read = seq_read, + .write = sn2_ptc_proc_write, .llseek = seq_lseek, .release = seq_release, }; -- cgit v1.2.3