path: root/kernel/power/tuxonice_alloc.c

/*
 * kernel/power/tuxonice_alloc.c
 *
 * Copyright (C) 2008-2015 Nigel Cunningham (nigel at nigelcunningham com au)
 *
 * This file is released under the GPLv2.
 *
 */

#include <linux/export.h>
#include <linux/slab.h>
#include "tuxonice_modules.h"
#include "tuxonice_alloc.h"
#include "tuxonice_sysfs.h"
#include "tuxonice.h"

#define TOI_ALLOC_PATHS 41

static DEFINE_MUTEX(toi_alloc_mutex);

static struct toi_module_ops toi_alloc_ops;

static int toi_fail_num;

static atomic_t toi_alloc_count[TOI_ALLOC_PATHS],
                toi_free_count[TOI_ALLOC_PATHS],
                toi_test_count[TOI_ALLOC_PATHS],
                toi_fail_count[TOI_ALLOC_PATHS];
static int toi_cur_allocd[TOI_ALLOC_PATHS], toi_max_allocd[TOI_ALLOC_PATHS];
static int cur_allocd, max_allocd;

static char *toi_alloc_desc[TOI_ALLOC_PATHS] = {
        "", /* 0 */
        "get_io_info_struct",
        "extent",
        "extent (loading chain)",
        "userui channel",
        "userui arg", /* 5 */
        "attention list metadata",
        "extra pagedir memory metadata",
        "bdev metadata",
        "extra pagedir memory",
        "header_locations_read", /* 10 */
        "bio queue",
        "prepare_readahead",
        "i/o buffer",
        "writer buffer in bio_init",
        "checksum buffer", /* 15 */
        "compression buffer",
        "filewriter signature op",
        "set resume param alloc1",
        "set resume param alloc2",
        "debugging info buffer", /* 20 */
        "check can resume buffer",
        "write module config buffer",
        "read module config buffer",
        "write image header buffer",
        "read pageset1 buffer", /* 25 */
        "get_have_image_data buffer",
        "checksum page",
        "worker rw loop",
        "get nonconflicting page",
        "ps1 load addresses", /* 30 */
        "remove swap image",
        "swap image exists",
        "swap parse sig location",
        "sysfs kobj",
        "swap mark resume attempted buffer", /* 35 */
        "cluster member",
        "boot kernel data buffer",
        "setting swap signature",
        "block i/o bdev struct",
        "copy before write", /* 40 */
};

#define MIGHT_FAIL(FAIL_NUM, FAIL_VAL) \
        do { \
                BUG_ON(FAIL_NUM >= TOI_ALLOC_PATHS); \
                \
                if (FAIL_NUM == toi_fail_num) { \
                        atomic_inc(&toi_test_count[FAIL_NUM]); \
                        toi_fail_num = 0; \
                        return FAIL_VAL; \
                } \
        } while (0)

static void alloc_update_stats(int fail_num, void *result, int size)
{
        if (!result) {
                atomic_inc(&toi_fail_count[fail_num]);
                return;
        }

        atomic_inc(&toi_alloc_count[fail_num]);
        if (unlikely(test_action_state(TOI_GET_MAX_MEM_ALLOCD))) {
                mutex_lock(&toi_alloc_mutex);
                toi_cur_allocd[fail_num]++;
                cur_allocd += size;
                if (unlikely(cur_allocd > max_allocd)) {
                        int i;

                        for (i = 0; i < TOI_ALLOC_PATHS; i++)
                                toi_max_allocd[i] = toi_cur_allocd[i];
                        max_allocd = cur_allocd;
                }
                mutex_unlock(&toi_alloc_mutex);
        }
}

static void free_update_stats(int fail_num, int size)
{
        BUG_ON(fail_num >= TOI_ALLOC_PATHS);
        atomic_inc(&toi_free_count[fail_num]);
        if (unlikely(atomic_read(&toi_free_count[fail_num]) >
                                atomic_read(&toi_alloc_count[fail_num])))
                dump_stack();
        if (unlikely(test_action_state(TOI_GET_MAX_MEM_ALLOCD))) {
                mutex_lock(&toi_alloc_mutex);
                cur_allocd -= size;
                toi_cur_allocd[fail_num]--;
                mutex_unlock(&toi_alloc_mutex);
        }
}

void *toi_kzalloc(int fail_num, size_t size, gfp_t flags)
{
        void *result;

        if (toi_alloc_ops.enabled)
                MIGHT_FAIL(fail_num, NULL);
        result = kzalloc(size, flags);
        if (toi_alloc_ops.enabled)
                alloc_update_stats(fail_num, result, size);
        if (fail_num == toi_trace_allocs)
                dump_stack();
        return result;
}

unsigned long toi_get_free_pages(int fail_num, gfp_t mask,
                unsigned int order)
{
        unsigned long result;

        mask |= ___GFP_TOI_NOTRACK;
        if (toi_alloc_ops.enabled)
                MIGHT_FAIL(fail_num, 0);
        result = __get_free_pages(mask, order);
        if (toi_alloc_ops.enabled)
                alloc_update_stats(fail_num, (void *) result,
                                PAGE_SIZE << order);
        if (fail_num == toi_trace_allocs)
                dump_stack();
        return result;
}

struct page *toi_alloc_page(int fail_num, gfp_t mask)
{
        struct page *result;

        if (toi_alloc_ops.enabled)
                MIGHT_FAIL(fail_num, NULL);
        mask |= ___GFP_TOI_NOTRACK;
        result = alloc_page(mask);
        if (toi_alloc_ops.enabled)
                alloc_update_stats(fail_num, (void *) result, PAGE_SIZE);
        if (fail_num == toi_trace_allocs)
                dump_stack();
        return result;
}

unsigned long toi_get_zeroed_page(int fail_num, gfp_t mask)
{
        unsigned long result;

        if (toi_alloc_ops.enabled)
                MIGHT_FAIL(fail_num, 0);
        mask |= ___GFP_TOI_NOTRACK;
        result = get_zeroed_page(mask);
        if (toi_alloc_ops.enabled)
                alloc_update_stats(fail_num, (void *) result, PAGE_SIZE);
        if (fail_num == toi_trace_allocs)
                dump_stack();
        return result;
}

void toi_kfree(int fail_num, const void *arg, int size)
{
        if (arg && toi_alloc_ops.enabled)
                free_update_stats(fail_num, size);

        if (fail_num == toi_trace_allocs)
                dump_stack();
        kfree(arg);
}

void toi_free_page(int fail_num, unsigned long virt)
{
        if (virt && toi_alloc_ops.enabled)
                free_update_stats(fail_num, PAGE_SIZE);

        if (fail_num == toi_trace_allocs)
                dump_stack();
        free_page(virt);
}

void toi__free_page(int fail_num, struct page *page)
{
        if (page && toi_alloc_ops.enabled)
                free_update_stats(fail_num, PAGE_SIZE);

        if (fail_num == toi_trace_allocs)
                dump_stack();
        __free_page(page);
}

void toi_free_pages(int fail_num, struct page *page, int order)
{
        if (page && toi_alloc_ops.enabled)
                free_update_stats(fail_num, PAGE_SIZE << order);

        if (fail_num == toi_trace_allocs)
                dump_stack();
        __free_pages(page, order);
}

void toi_alloc_print_debug_stats(void)
{
        int i, header_done = 0;

        if (!toi_alloc_ops.enabled)
                return;

        for (i = 0; i < TOI_ALLOC_PATHS; i++)
                if (atomic_read(&toi_alloc_count[i]) !=
                    atomic_read(&toi_free_count[i])) {
                        if (!header_done) {
                                printk(KERN_INFO "Idx  Allocs   Frees   Tests "
                                        "  Fails     Max Description\n");
                                header_done = 1;
                        }

                        printk(KERN_INFO "%3d %7d %7d %7d %7d %7d %s\n", i,
                                atomic_read(&toi_alloc_count[i]),
                                atomic_read(&toi_free_count[i]),
                                atomic_read(&toi_test_count[i]),
                                atomic_read(&toi_fail_count[i]),
                                toi_max_allocd[i],
                                toi_alloc_desc[i]);
                }
}

static int toi_alloc_initialise(int starting_cycle)
{
        int i;

        if (!starting_cycle)
                return 0;

        if (toi_trace_allocs)
                dump_stack();

        for (i = 0; i < TOI_ALLOC_PATHS; i++) {
                atomic_set(&toi_alloc_count[i], 0);
                atomic_set(&toi_free_count[i], 0);
                atomic_set(&toi_test_count[i], 0);
                atomic_set(&toi_fail_count[i], 0);
                toi_cur_allocd[i] = 0;
                toi_max_allocd[i] = 0;
        };

        max_allocd = 0;
        cur_allocd = 0;
        return 0;
}

static struct toi_sysfs_data sysfs_params[] = {
        SYSFS_INT("failure_test", SYSFS_RW, &toi_fail_num, 0, 99, 0, NULL),
        SYSFS_INT("trace", SYSFS_RW, &toi_trace_allocs, 0, TOI_ALLOC_PATHS, 0,
                        NULL),
        SYSFS_BIT("find_max_mem_allocated", SYSFS_RW, &toi_bkd.toi_action,
                        TOI_GET_MAX_MEM_ALLOCD, 0),
        SYSFS_INT("enabled", SYSFS_RW, &toi_alloc_ops.enabled, 0, 1, 0,
                        NULL)
};

static struct toi_module_ops toi_alloc_ops = {
        .type                                        = MISC_HIDDEN_MODULE,
        .name                                        = "allocation debugging",
        .directory                                = "alloc",
        .module                                        = THIS_MODULE,
        .early                                        = 1,
        .initialise                                = toi_alloc_initialise,

        .sysfs_data                = sysfs_params,
        .num_sysfs_entries        = sizeof(sysfs_params) /
                sizeof(struct toi_sysfs_data),
};

int toi_alloc_init(void)
{
        int result = toi_register_module(&toi_alloc_ops);
        return result;
}

void toi_alloc_exit(void)
{
        toi_unregister_module(&toi_alloc_ops);
}