Commit 257ffc64 authored by Linas Vepstas's avatar Linas Vepstas Committed by Paul Mackerras
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[PATCH] powerpc: get rid of per_cpu EEH counters 



242-eeh-no-percpu-counters.patch

Remove per-cpu counters from the EEH code.  These statistics counters
are incremented at a very low frequency, and the performance gains of
per-cpu variables are negligable.  By contrast, the counters weren't
safe against cpu off/online operations, and its not worth the effort
to make them so (other than to turn them into plain globals).

Signed-off-by: default avatarLinas Vepstas <linas@austin.ibm.com>
Signed-off-by: default avatarPaul Mackerras <paulus@samba.org>
(cherry picked from be3b5d1be053ccb41e91fa5a6f43ef5db301357d commit)
parent 7684b40c

arch/powerpc/platforms/pseries/eeh.c

+23 −37
Original line number Diff line number Diff line
@@ -97,14 +97,14 @@ static DEFINE_SPINLOCK(slot_errbuf_lock); 
static int eeh_error_buf_size;



/* System monitoring statistics */

static DEFINE_PER_CPU(unsigned long, no_device);

static DEFINE_PER_CPU(unsigned long, no_dn);

static DEFINE_PER_CPU(unsigned long, no_cfg_addr);

static DEFINE_PER_CPU(unsigned long, ignored_check);

static DEFINE_PER_CPU(unsigned long, total_mmio_ffs);

static DEFINE_PER_CPU(unsigned long, false_positives);

static DEFINE_PER_CPU(unsigned long, ignored_failures);

static DEFINE_PER_CPU(unsigned long, slot_resets);

static unsigned long no_device;

static unsigned long no_dn;

static unsigned long no_cfg_addr;

static unsigned long ignored_check;

static unsigned long total_mmio_ffs;

static unsigned long false_positives;

static unsigned long ignored_failures;

static unsigned long slot_resets;



#define IS_BRIDGE(class_code) (((class_code)<<16) == PCI_BASE_CLASS_BRIDGE)
@@ -288,13 +288,13 @@ int eeh_dn_check_failure(struct device_node *dn, struct pci_dev *dev) 
	enum pci_channel_state state;

	int rc = 0;



	__get_cpu_var(total_mmio_ffs)++;

	total_mmio_ffs++;



	if (!eeh_subsystem_enabled)

		return 0;



	if (!dn) {

		__get_cpu_var(no_dn)++;

		no_dn++;

		return 0;

	}

	pdn = PCI_DN(dn);
@@ -302,7 +302,7 @@ int eeh_dn_check_failure(struct device_node *dn, struct pci_dev *dev) 
	/* Access to IO BARs might get this far and still not want checking. */

	if (!(pdn->eeh_mode & EEH_MODE_SUPPORTED) ||

	    pdn->eeh_mode & EEH_MODE_NOCHECK) {

		__get_cpu_var(ignored_check)++;

		ignored_check++;

#ifdef DEBUG

		printk ("EEH:ignored check (%x) for %s %s\n", 

		        pdn->eeh_mode, pci_name (dev), dn->full_name);
@@ -311,7 +311,7 @@ int eeh_dn_check_failure(struct device_node *dn, struct pci_dev *dev) 
	}



	if (!pdn->eeh_config_addr && !pdn->eeh_pe_config_addr) {

		__get_cpu_var(no_cfg_addr)++;

		no_cfg_addr++;

		return 0;

	}
@@ -353,7 +353,7 @@ int eeh_dn_check_failure(struct device_node *dn, struct pci_dev *dev) 
	if (ret != 0) {

		printk(KERN_WARNING "EEH: read_slot_reset_state() failed; rc=%d dn=%s\n",

		       ret, dn->full_name);

		__get_cpu_var(false_positives)++;

		false_positives++;

		rc = 0;

		goto dn_unlock;

	}
@@ -362,14 +362,14 @@ int eeh_dn_check_failure(struct device_node *dn, struct pci_dev *dev) 
	if (rets[1] != 1) {

		printk(KERN_WARNING "EEH: event on unsupported device, rc=%d dn=%s\n",

		       ret, dn->full_name);

		__get_cpu_var(false_positives)++;

		false_positives++;

		rc = 0;

		goto dn_unlock;

	}



	/* If not the kind of error we know about, punt. */

	if (rets[0] != 2 && rets[0] != 4 && rets[0] != 5) {

		__get_cpu_var(false_positives)++;

		false_positives++;

		rc = 0;

		goto dn_unlock;

	}
@@ -377,12 +377,12 @@ int eeh_dn_check_failure(struct device_node *dn, struct pci_dev *dev) 
	/* Note that config-io to empty slots may fail;

	 * we recognize empty because they don't have children. */

	if ((rets[0] == 5) && (dn->child == NULL)) {

		__get_cpu_var(false_positives)++;

		false_positives++;

		rc = 0;

		goto dn_unlock;

	}



	__get_cpu_var(slot_resets)++;

	slot_resets++;

 

	/* Avoid repeated reports of this failure, including problems

	 * with other functions on this device, and functions under
@@ -432,7 +432,7 @@ unsigned long eeh_check_failure(const volatile void __iomem *token, unsigned lon 
	addr = eeh_token_to_phys((unsigned long __force) token);

	dev = pci_get_device_by_addr(addr);

	if (!dev) {

		__get_cpu_var(no_device)++;

		no_device++;

		return val;

	}
@@ -963,25 +963,9 @@ EXPORT_SYMBOL_GPL(eeh_remove_bus_device); 


static int proc_eeh_show(struct seq_file *m, void *v)

{

	unsigned int cpu;

	unsigned long ffs = 0, positives = 0, failures = 0;

	unsigned long resets = 0;

	unsigned long no_dev = 0, no_dn = 0, no_cfg = 0, no_check = 0;



	for_each_cpu(cpu) {

		ffs += per_cpu(total_mmio_ffs, cpu);

		positives += per_cpu(false_positives, cpu);

		failures += per_cpu(ignored_failures, cpu);

		resets += per_cpu(slot_resets, cpu);

		no_dev += per_cpu(no_device, cpu);

		no_dn += per_cpu(no_dn, cpu);

		no_cfg += per_cpu(no_cfg_addr, cpu);

		no_check += per_cpu(ignored_check, cpu);

	}



	if (0 == eeh_subsystem_enabled) {

		seq_printf(m, "EEH Subsystem is globally disabled\n");

		seq_printf(m, "eeh_total_mmio_ffs=%ld\n", ffs);

		seq_printf(m, "eeh_total_mmio_ffs=%ld\n", total_mmio_ffs);

	} else {

		seq_printf(m, "EEH Subsystem is enabled\n");

		seq_printf(m,
@@ -993,8 +977,10 @@ static int proc_eeh_show(struct seq_file *m, void *v) 
				"eeh_false_positives=%ld\n"

				"eeh_ignored_failures=%ld\n"

				"eeh_slot_resets=%ld\n",

				no_dev, no_dn, no_cfg, no_check,

				ffs, positives, failures, resets);

				no_device, no_dn, no_cfg_addr, 

				ignored_check, total_mmio_ffs, 

				false_positives, ignored_failures, 

				slot_resets);

	}



	return 0;

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