root/tools/perf/builtin-kmem.c
// SPDX-License-Identifier: GPL-2.0
#include "builtin.h"

#include "util/dso.h"
#include "util/evlist.h"
#include "util/evsel.h"
#include "util/config.h"
#include "util/map.h"
#include "util/symbol.h"
#include "util/thread.h"
#include "util/header.h"
#include "util/session.h"
#include "util/tool.h"
#include "util/callchain.h"
#include "util/time-utils.h"
#include <linux/err.h>

#include <subcmd/pager.h>
#include <subcmd/parse-options.h>
#include "util/trace-event.h"
#include "util/data.h"
#include "util/cpumap.h"

#include "util/debug.h"
#include "util/string2.h"
#include "util/util.h"

#include <linux/kernel.h>
#include <linux/numa.h>
#include <linux/rbtree.h>
#include <linux/string.h>
#include <linux/zalloc.h>
#include <errno.h>
#include <inttypes.h>
#include <locale.h>
#include <regex.h>

#include <linux/ctype.h>
#include <event-parse.h>

static int      kmem_slab;
static int      kmem_page;

static long     kmem_page_size;
static enum {
        KMEM_SLAB,
        KMEM_PAGE,
} kmem_default = KMEM_SLAB;  /* for backward compatibility */

struct alloc_stat;
typedef int (*sort_fn_t)(void *, void *);

static int                      alloc_flag;
static int                      caller_flag;

static int                      alloc_lines = -1;
static int                      caller_lines = -1;

static bool                     raw_ip;

struct alloc_stat {
        u64     call_site;
        u64     ptr;
        u64     bytes_req;
        u64     bytes_alloc;
        u64     last_alloc;
        u32     hit;
        u32     pingpong;

        short   alloc_cpu;

        struct rb_node node;
};

static struct rb_root root_alloc_stat;
static struct rb_root root_alloc_sorted;
static struct rb_root root_caller_stat;
static struct rb_root root_caller_sorted;

static unsigned long total_requested, total_allocated, total_freed;
static unsigned long nr_allocs, nr_cross_allocs;

/* filters for controlling start and stop of time of analysis */
static struct perf_time_interval ptime;
const char *time_str;

static int insert_alloc_stat(unsigned long call_site, unsigned long ptr,
                             int bytes_req, int bytes_alloc, int cpu)
{
        struct rb_node **node = &root_alloc_stat.rb_node;
        struct rb_node *parent = NULL;
        struct alloc_stat *data = NULL;

        while (*node) {
                parent = *node;
                data = rb_entry(*node, struct alloc_stat, node);

                if (ptr > data->ptr)
                        node = &(*node)->rb_right;
                else if (ptr < data->ptr)
                        node = &(*node)->rb_left;
                else
                        break;
        }

        if (data && data->ptr == ptr) {
                data->hit++;
                data->bytes_req += bytes_req;
                data->bytes_alloc += bytes_alloc;
        } else {
                data = malloc(sizeof(*data));
                if (!data) {
                        pr_err("%s: malloc failed\n", __func__);
                        return -1;
                }
                data->ptr = ptr;
                data->pingpong = 0;
                data->hit = 1;
                data->bytes_req = bytes_req;
                data->bytes_alloc = bytes_alloc;

                rb_link_node(&data->node, parent, node);
                rb_insert_color(&data->node, &root_alloc_stat);
        }
        data->call_site = call_site;
        data->alloc_cpu = cpu;
        data->last_alloc = bytes_alloc;

        return 0;
}

static int insert_caller_stat(unsigned long call_site,
                              int bytes_req, int bytes_alloc)
{
        struct rb_node **node = &root_caller_stat.rb_node;
        struct rb_node *parent = NULL;
        struct alloc_stat *data = NULL;

        while (*node) {
                parent = *node;
                data = rb_entry(*node, struct alloc_stat, node);

                if (call_site > data->call_site)
                        node = &(*node)->rb_right;
                else if (call_site < data->call_site)
                        node = &(*node)->rb_left;
                else
                        break;
        }

        if (data && data->call_site == call_site) {
                data->hit++;
                data->bytes_req += bytes_req;
                data->bytes_alloc += bytes_alloc;
        } else {
                data = malloc(sizeof(*data));
                if (!data) {
                        pr_err("%s: malloc failed\n", __func__);
                        return -1;
                }
                data->call_site = call_site;
                data->pingpong = 0;
                data->hit = 1;
                data->bytes_req = bytes_req;
                data->bytes_alloc = bytes_alloc;

                rb_link_node(&data->node, parent, node);
                rb_insert_color(&data->node, &root_caller_stat);
        }

        return 0;
}

static int evsel__process_alloc_event(struct evsel *evsel, struct perf_sample *sample)
{
        unsigned long ptr = evsel__intval(evsel, sample, "ptr"),
                      call_site = evsel__intval(evsel, sample, "call_site");
        int bytes_req = evsel__intval(evsel, sample, "bytes_req"),
            bytes_alloc = evsel__intval(evsel, sample, "bytes_alloc");

        if (insert_alloc_stat(call_site, ptr, bytes_req, bytes_alloc, sample->cpu) ||
            insert_caller_stat(call_site, bytes_req, bytes_alloc))
                return -1;

        total_requested += bytes_req;
        total_allocated += bytes_alloc;

        nr_allocs++;

        /*
         * Commit 11e9734bcb6a ("mm/slab_common: unify NUMA and UMA
         * version of tracepoints") adds the field "node" into the
         * tracepoints 'kmalloc' and 'kmem_cache_alloc'.
         *
         * The legacy tracepoints 'kmalloc_node' and 'kmem_cache_alloc_node'
         * also contain the field "node".
         *
         * If the tracepoint contains the field "node" the tool stats the
         * cross allocation.
         */
        if (evsel__field(evsel, "node")) {
                int node1, node2;

                node1 = cpu__get_node((struct perf_cpu){.cpu = sample->cpu});
                node2 = evsel__intval(evsel, sample, "node");

                /*
                 * If the field "node" is NUMA_NO_NODE (-1), we don't take it
                 * as a cross allocation.
                 */
                if ((node2 != NUMA_NO_NODE) && (node1 != node2))
                        nr_cross_allocs++;
        }

        return 0;
}

static int ptr_cmp(void *, void *);
static int slab_callsite_cmp(void *, void *);

static struct alloc_stat *search_alloc_stat(unsigned long ptr,
                                            unsigned long call_site,
                                            struct rb_root *root,
                                            sort_fn_t sort_fn)
{
        struct rb_node *node = root->rb_node;
        struct alloc_stat key = { .ptr = ptr, .call_site = call_site };

        while (node) {
                struct alloc_stat *data;
                int cmp;

                data = rb_entry(node, struct alloc_stat, node);

                cmp = sort_fn(&key, data);
                if (cmp < 0)
                        node = node->rb_left;
                else if (cmp > 0)
                        node = node->rb_right;
                else
                        return data;
        }
        return NULL;
}

static int evsel__process_free_event(struct evsel *evsel, struct perf_sample *sample)
{
        unsigned long ptr = evsel__intval(evsel, sample, "ptr");
        struct alloc_stat *s_alloc, *s_caller;

        s_alloc = search_alloc_stat(ptr, 0, &root_alloc_stat, ptr_cmp);
        if (!s_alloc)
                return 0;

        total_freed += s_alloc->last_alloc;

        if ((short)sample->cpu != s_alloc->alloc_cpu) {
                s_alloc->pingpong++;

                s_caller = search_alloc_stat(0, s_alloc->call_site,
                                             &root_caller_stat,
                                             slab_callsite_cmp);
                if (!s_caller)
                        return -1;
                s_caller->pingpong++;
        }
        s_alloc->alloc_cpu = -1;

        return 0;
}

static u64 total_page_alloc_bytes;
static u64 total_page_free_bytes;
static u64 total_page_nomatch_bytes;
static u64 total_page_fail_bytes;
static unsigned long nr_page_allocs;
static unsigned long nr_page_frees;
static unsigned long nr_page_fails;
static unsigned long nr_page_nomatch;

static bool use_pfn;
static bool live_page;
static struct perf_session *kmem_session;

#define MAX_MIGRATE_TYPES  6
#define MAX_PAGE_ORDER     11

static int order_stats[MAX_PAGE_ORDER][MAX_MIGRATE_TYPES];

struct page_stat {
        struct rb_node  node;
        u64             page;
        u64             callsite;
        int             order;
        unsigned        gfp_flags;
        unsigned        migrate_type;
        u64             alloc_bytes;
        u64             free_bytes;
        int             nr_alloc;
        int             nr_free;
};

static struct rb_root page_live_tree;
static struct rb_root page_alloc_tree;
static struct rb_root page_alloc_sorted;
static struct rb_root page_caller_tree;
static struct rb_root page_caller_sorted;

struct alloc_func {
        u64 start;
        u64 end;
        char *name;
};

static int nr_alloc_funcs;
static struct alloc_func *alloc_func_list;

static int funcmp(const void *a, const void *b)
{
        const struct alloc_func *fa = a;
        const struct alloc_func *fb = b;

        if (fa->start > fb->start)
                return 1;
        else
                return -1;
}

static int callcmp(const void *a, const void *b)
{
        const struct alloc_func *fa = a;
        const struct alloc_func *fb = b;

        if (fb->start <= fa->start && fa->end < fb->end)
                return 0;

        if (fa->start > fb->start)
                return 1;
        else
                return -1;
}

static int build_alloc_func_list(void)
{
        int ret;
        struct map *kernel_map;
        struct symbol *sym;
        struct rb_node *node;
        struct alloc_func *func;
        struct machine *machine = &kmem_session->machines.host;
        regex_t alloc_func_regex;
        static const char pattern[] = "^_?_?(alloc|get_free|get_zeroed)_pages?";

        ret = regcomp(&alloc_func_regex, pattern, REG_EXTENDED);
        if (ret) {
                char err[BUFSIZ];

                regerror(ret, &alloc_func_regex, err, sizeof(err));
                pr_err("Invalid regex: %s\n%s", pattern, err);
                return -EINVAL;
        }

        kernel_map = machine__kernel_map(machine);
        if (map__load(kernel_map) < 0) {
                pr_err("cannot load kernel map\n");
                return -ENOENT;
        }

        map__for_each_symbol(kernel_map, sym, node) {
                if (regexec(&alloc_func_regex, sym->name, 0, NULL, 0))
                        continue;

                func = realloc(alloc_func_list,
                               (nr_alloc_funcs + 1) * sizeof(*func));
                if (func == NULL)
                        return -ENOMEM;

                pr_debug("alloc func: %s\n", sym->name);
                func[nr_alloc_funcs].start = sym->start;
                func[nr_alloc_funcs].end   = sym->end;
                func[nr_alloc_funcs].name  = sym->name;

                alloc_func_list = func;
                nr_alloc_funcs++;
        }

        qsort(alloc_func_list, nr_alloc_funcs, sizeof(*func), funcmp);

        regfree(&alloc_func_regex);
        return 0;
}

/*
 * Find first non-memory allocation function from callchain.
 * The allocation functions are in the 'alloc_func_list'.
 */
static u64 find_callsite(struct evsel *evsel, struct perf_sample *sample)
{
        struct addr_location al;
        struct machine *machine = &kmem_session->machines.host;
        struct callchain_cursor_node *node;
        struct callchain_cursor *cursor;
        u64 result = sample->ip;

        addr_location__init(&al);
        if (alloc_func_list == NULL) {
                if (build_alloc_func_list() < 0)
                        goto out;
        }

        al.thread = machine__findnew_thread(machine, sample->pid, sample->tid);

        cursor = get_tls_callchain_cursor();
        if (cursor == NULL)
                goto out;

        sample__resolve_callchain(sample, cursor, NULL, evsel, &al, 16);

        callchain_cursor_commit(cursor);
        while (true) {
                struct alloc_func key, *caller;
                u64 addr;

                node = callchain_cursor_current(cursor);
                if (node == NULL)
                        break;

                key.start = key.end = node->ip;
                caller = bsearch(&key, alloc_func_list, nr_alloc_funcs,
                                 sizeof(key), callcmp);
                if (!caller) {
                        /* found */
                        if (node->ms.map)
                                addr = map__dso_unmap_ip(node->ms.map, node->ip);
                        else
                                addr = node->ip;

                        result = addr;
                        goto out;
                } else
                        pr_debug3("skipping alloc function: %s\n", caller->name);

                callchain_cursor_advance(cursor);
        }

        pr_debug2("unknown callsite: %"PRIx64 "\n", sample->ip);
out:
        addr_location__exit(&al);
        return result;
}

struct sort_dimension {
        const char              name[20];
        sort_fn_t               cmp;
        struct list_head        list;
};

static LIST_HEAD(page_alloc_sort_input);
static LIST_HEAD(page_caller_sort_input);

static struct page_stat *
__page_stat__findnew_page(struct page_stat *pstat, bool create)
{
        struct rb_node **node = &page_live_tree.rb_node;
        struct rb_node *parent = NULL;
        struct page_stat *data;

        while (*node) {
                s64 cmp;

                parent = *node;
                data = rb_entry(*node, struct page_stat, node);

                cmp = data->page - pstat->page;
                if (cmp < 0)
                        node = &parent->rb_left;
                else if (cmp > 0)
                        node = &parent->rb_right;
                else
                        return data;
        }

        if (!create)
                return NULL;

        data = zalloc(sizeof(*data));
        if (data != NULL) {
                data->page = pstat->page;
                data->order = pstat->order;
                data->gfp_flags = pstat->gfp_flags;
                data->migrate_type = pstat->migrate_type;

                rb_link_node(&data->node, parent, node);
                rb_insert_color(&data->node, &page_live_tree);
        }

        return data;
}

static struct page_stat *page_stat__find_page(struct page_stat *pstat)
{
        return __page_stat__findnew_page(pstat, false);
}

static struct page_stat *page_stat__findnew_page(struct page_stat *pstat)
{
        return __page_stat__findnew_page(pstat, true);
}

static struct page_stat *
__page_stat__findnew_alloc(struct page_stat *pstat, bool create)
{
        struct rb_node **node = &page_alloc_tree.rb_node;
        struct rb_node *parent = NULL;
        struct page_stat *data;
        struct sort_dimension *sort;

        while (*node) {
                int cmp = 0;

                parent = *node;
                data = rb_entry(*node, struct page_stat, node);

                list_for_each_entry(sort, &page_alloc_sort_input, list) {
                        cmp = sort->cmp(pstat, data);
                        if (cmp)
                                break;
                }

                if (cmp < 0)
                        node = &parent->rb_left;
                else if (cmp > 0)
                        node = &parent->rb_right;
                else
                        return data;
        }

        if (!create)
                return NULL;

        data = zalloc(sizeof(*data));
        if (data != NULL) {
                data->page = pstat->page;
                data->order = pstat->order;
                data->gfp_flags = pstat->gfp_flags;
                data->migrate_type = pstat->migrate_type;

                rb_link_node(&data->node, parent, node);
                rb_insert_color(&data->node, &page_alloc_tree);
        }

        return data;
}

static struct page_stat *page_stat__find_alloc(struct page_stat *pstat)
{
        return __page_stat__findnew_alloc(pstat, false);
}

static struct page_stat *page_stat__findnew_alloc(struct page_stat *pstat)
{
        return __page_stat__findnew_alloc(pstat, true);
}

static struct page_stat *
__page_stat__findnew_caller(struct page_stat *pstat, bool create)
{
        struct rb_node **node = &page_caller_tree.rb_node;
        struct rb_node *parent = NULL;
        struct page_stat *data;
        struct sort_dimension *sort;

        while (*node) {
                int cmp = 0;

                parent = *node;
                data = rb_entry(*node, struct page_stat, node);

                list_for_each_entry(sort, &page_caller_sort_input, list) {
                        cmp = sort->cmp(pstat, data);
                        if (cmp)
                                break;
                }

                if (cmp < 0)
                        node = &parent->rb_left;
                else if (cmp > 0)
                        node = &parent->rb_right;
                else
                        return data;
        }

        if (!create)
                return NULL;

        data = zalloc(sizeof(*data));
        if (data != NULL) {
                data->callsite = pstat->callsite;
                data->order = pstat->order;
                data->gfp_flags = pstat->gfp_flags;
                data->migrate_type = pstat->migrate_type;

                rb_link_node(&data->node, parent, node);
                rb_insert_color(&data->node, &page_caller_tree);
        }

        return data;
}

static struct page_stat *page_stat__find_caller(struct page_stat *pstat)
{
        return __page_stat__findnew_caller(pstat, false);
}

static struct page_stat *page_stat__findnew_caller(struct page_stat *pstat)
{
        return __page_stat__findnew_caller(pstat, true);
}

static bool valid_page(u64 pfn_or_page)
{
        if (use_pfn && pfn_or_page == -1UL)
                return false;
        if (!use_pfn && pfn_or_page == 0)
                return false;
        return true;
}

struct gfp_flag {
        unsigned int flags;
        char *compact_str;
        char *human_readable;
};

static struct gfp_flag *gfps;
static int nr_gfps;

static int gfpcmp(const void *a, const void *b)
{
        const struct gfp_flag *fa = a;
        const struct gfp_flag *fb = b;

        return fa->flags - fb->flags;
}

/* see include/trace/events/mmflags.h */
static const struct {
        const char *original;
        const char *compact;
} gfp_compact_table[] = {
        { "GFP_TRANSHUGE",              "THP" },
        { "GFP_TRANSHUGE_LIGHT",        "THL" },
        { "GFP_HIGHUSER_MOVABLE",       "HUM" },
        { "GFP_HIGHUSER",               "HU" },
        { "GFP_USER",                   "U" },
        { "GFP_KERNEL_ACCOUNT",         "KAC" },
        { "GFP_KERNEL",                 "K" },
        { "GFP_NOFS",                   "NF" },
        { "GFP_ATOMIC",                 "A" },
        { "GFP_NOIO",                   "NI" },
        { "GFP_NOWAIT",                 "NW" },
        { "GFP_DMA",                    "D" },
        { "__GFP_HIGHMEM",              "HM" },
        { "GFP_DMA32",                  "D32" },
        { "__GFP_HIGH",                 "H" },
        { "__GFP_IO",                   "I" },
        { "__GFP_FS",                   "F" },
        { "__GFP_NOWARN",               "NWR" },
        { "__GFP_RETRY_MAYFAIL",        "R" },
        { "__GFP_NOFAIL",               "NF" },
        { "__GFP_NORETRY",              "NR" },
        { "__GFP_COMP",                 "C" },
        { "__GFP_ZERO",                 "Z" },
        { "__GFP_NOMEMALLOC",           "NMA" },
        { "__GFP_MEMALLOC",             "MA" },
        { "__GFP_HARDWALL",             "HW" },
        { "__GFP_THISNODE",             "TN" },
        { "__GFP_RECLAIMABLE",          "RC" },
        { "__GFP_MOVABLE",              "M" },
        { "__GFP_ACCOUNT",              "AC" },
        { "__GFP_WRITE",                "WR" },
        { "__GFP_RECLAIM",              "R" },
        { "__GFP_DIRECT_RECLAIM",       "DR" },
        { "__GFP_KSWAPD_RECLAIM",       "KR" },
};

static size_t max_gfp_len;

static char *compact_gfp_flags(char *gfp_flags)
{
        char *orig_flags = strdup(gfp_flags);
        char *new_flags = NULL;
        char *str, *pos = NULL;
        size_t len = 0;

        if (orig_flags == NULL)
                return NULL;

        str = strtok_r(orig_flags, "|", &pos);
        while (str) {
                size_t i;
                char *new;
                const char *cpt;

                for (i = 0; i < ARRAY_SIZE(gfp_compact_table); i++) {
                        if (strcmp(gfp_compact_table[i].original, str))
                                continue;

                        cpt = gfp_compact_table[i].compact;
                        new = realloc(new_flags, len + strlen(cpt) + 2);
                        if (new == NULL) {
                                free(new_flags);
                                free(orig_flags);
                                return NULL;
                        }

                        new_flags = new;

                        if (!len) {
                                strcpy(new_flags, cpt);
                        } else {
                                strcat(new_flags, "|");
                                strcat(new_flags, cpt);
                                len++;
                        }

                        len += strlen(cpt);
                }

                str = strtok_r(NULL, "|", &pos);
        }

        if (max_gfp_len < len)
                max_gfp_len = len;

        free(orig_flags);
        return new_flags;
}

static char *compact_gfp_string(unsigned long gfp_flags)
{
        struct gfp_flag key = {
                .flags = gfp_flags,
        };
        struct gfp_flag *gfp;

        gfp = bsearch(&key, gfps, nr_gfps, sizeof(*gfps), gfpcmp);
        if (gfp)
                return gfp->compact_str;

        return NULL;
}

static int parse_gfp_flags(struct evsel *evsel, struct perf_sample *sample,
                           unsigned int gfp_flags)
{
        struct tep_record record = {
                .cpu = sample->cpu,
                .data = sample->raw_data,
                .size = sample->raw_size,
        };
        struct trace_seq seq;
        char *str, *pos = NULL;
        const struct tep_event *tp_format;

        if (nr_gfps) {
                struct gfp_flag key = {
                        .flags = gfp_flags,
                };

                if (bsearch(&key, gfps, nr_gfps, sizeof(*gfps), gfpcmp))
                        return 0;
        }

        trace_seq_init(&seq);
        tp_format = evsel__tp_format(evsel);
        if (tp_format)
                tep_print_event(tp_format->tep, &seq, &record, "%s", TEP_PRINT_INFO);

        str = strtok_r(seq.buffer, " ", &pos);
        while (str) {
                if (!strncmp(str, "gfp_flags=", 10)) {
                        struct gfp_flag *new;

                        new = realloc(gfps, (nr_gfps + 1) * sizeof(*gfps));
                        if (new == NULL)
                                return -ENOMEM;

                        gfps = new;
                        new += nr_gfps++;

                        new->flags = gfp_flags;
                        new->human_readable = strdup(str + 10);
                        new->compact_str = compact_gfp_flags(str + 10);
                        if (!new->human_readable || !new->compact_str)
                                return -ENOMEM;

                        qsort(gfps, nr_gfps, sizeof(*gfps), gfpcmp);
                }

                str = strtok_r(NULL, " ", &pos);
        }

        trace_seq_destroy(&seq);
        return 0;
}

static int evsel__process_page_alloc_event(struct evsel *evsel, struct perf_sample *sample)
{
        u64 page;
        unsigned int order = evsel__intval(evsel, sample, "order");
        unsigned int gfp_flags = evsel__intval(evsel, sample, "gfp_flags");
        unsigned int migrate_type = evsel__intval(evsel, sample,
                                                       "migratetype");
        u64 bytes = kmem_page_size << order;
        u64 callsite;
        struct page_stat *pstat;
        struct page_stat this = {
                .order = order,
                .gfp_flags = gfp_flags,
                .migrate_type = migrate_type,
        };

        if (use_pfn)
                page = evsel__intval(evsel, sample, "pfn");
        else
                page = evsel__intval(evsel, sample, "page");

        nr_page_allocs++;
        total_page_alloc_bytes += bytes;

        if (!valid_page(page)) {
                nr_page_fails++;
                total_page_fail_bytes += bytes;

                return 0;
        }

        if (parse_gfp_flags(evsel, sample, gfp_flags) < 0)
                return -1;

        callsite = find_callsite(evsel, sample);

        /*
         * This is to find the current page (with correct gfp flags and
         * migrate type) at free event.
         */
        this.page = page;
        pstat = page_stat__findnew_page(&this);
        if (pstat == NULL)
                return -ENOMEM;

        pstat->nr_alloc++;
        pstat->alloc_bytes += bytes;
        pstat->callsite = callsite;

        if (!live_page) {
                pstat = page_stat__findnew_alloc(&this);
                if (pstat == NULL)
                        return -ENOMEM;

                pstat->nr_alloc++;
                pstat->alloc_bytes += bytes;
                pstat->callsite = callsite;
        }

        this.callsite = callsite;
        pstat = page_stat__findnew_caller(&this);
        if (pstat == NULL)
                return -ENOMEM;

        pstat->nr_alloc++;
        pstat->alloc_bytes += bytes;

        order_stats[order][migrate_type]++;

        return 0;
}

static int evsel__process_page_free_event(struct evsel *evsel, struct perf_sample *sample)
{
        u64 page;
        unsigned int order = evsel__intval(evsel, sample, "order");
        u64 bytes = kmem_page_size << order;
        struct page_stat *pstat;
        struct page_stat this = {
                .order = order,
        };

        if (use_pfn)
                page = evsel__intval(evsel, sample, "pfn");
        else
                page = evsel__intval(evsel, sample, "page");

        nr_page_frees++;
        total_page_free_bytes += bytes;

        this.page = page;
        pstat = page_stat__find_page(&this);
        if (pstat == NULL) {
                pr_debug2("missing free at page %"PRIx64" (order: %d)\n",
                          page, order);

                nr_page_nomatch++;
                total_page_nomatch_bytes += bytes;

                return 0;
        }

        this.gfp_flags = pstat->gfp_flags;
        this.migrate_type = pstat->migrate_type;
        this.callsite = pstat->callsite;

        rb_erase(&pstat->node, &page_live_tree);
        free(pstat);

        if (live_page) {
                order_stats[this.order][this.migrate_type]--;
        } else {
                pstat = page_stat__find_alloc(&this);
                if (pstat == NULL)
                        return -ENOMEM;

                pstat->nr_free++;
                pstat->free_bytes += bytes;
        }

        pstat = page_stat__find_caller(&this);
        if (pstat == NULL)
                return -ENOENT;

        pstat->nr_free++;
        pstat->free_bytes += bytes;

        if (live_page) {
                pstat->nr_alloc--;
                pstat->alloc_bytes -= bytes;

                if (pstat->nr_alloc == 0) {
                        rb_erase(&pstat->node, &page_caller_tree);
                        free(pstat);
                }
        }

        return 0;
}

static bool perf_kmem__skip_sample(struct perf_sample *sample)
{
        /* skip sample based on time? */
        if (perf_time__skip_sample(&ptime, sample->time))
                return true;

        return false;
}

typedef int (*tracepoint_handler)(struct evsel *evsel,
                                  struct perf_sample *sample);

static int process_sample_event(const struct perf_tool *tool __maybe_unused,
                                union perf_event *event,
                                struct perf_sample *sample,
                                struct evsel *evsel,
                                struct machine *machine)
{
        int err = 0;
        struct thread *thread = machine__findnew_thread(machine, sample->pid,
                                                        sample->tid);

        if (thread == NULL) {
                pr_debug("problem processing %d event, skipping it.\n",
                         event->header.type);
                return -1;
        }

        if (perf_kmem__skip_sample(sample))
                return 0;

        dump_printf(" ... thread: %s:%d\n", thread__comm_str(thread), thread__tid(thread));

        if (evsel->handler != NULL) {
                tracepoint_handler f = evsel->handler;
                err = f(evsel, sample);
        }

        thread__put(thread);

        return err;
}

static double fragmentation(unsigned long n_req, unsigned long n_alloc)
{
        if (n_alloc == 0)
                return 0.0;
        else
                return 100.0 - (100.0 * n_req / n_alloc);
}

static void __print_slab_result(struct rb_root *root,
                                struct perf_session *session,
                                int n_lines, int is_caller)
{
        struct rb_node *next;
        struct machine *machine = &session->machines.host;

        printf("%.105s\n", graph_dotted_line);
        printf(" %-34s |",  is_caller ? "Callsite": "Alloc Ptr");
        printf(" Total_alloc/Per | Total_req/Per   | Hit      | Ping-pong | Frag\n");
        printf("%.105s\n", graph_dotted_line);

        next = rb_first(root);

        while (next && n_lines--) {
                struct alloc_stat *data = rb_entry(next, struct alloc_stat,
                                                   node);
                struct symbol *sym = NULL;
                struct map *map;
                char buf[BUFSIZ];
                u64 addr;

                if (is_caller) {
                        addr = data->call_site;
                        if (!raw_ip)
                                sym = machine__find_kernel_symbol(machine, addr, &map);
                } else
                        addr = data->ptr;

                if (sym != NULL)
                        snprintf(buf, sizeof(buf), "%s+%" PRIx64 "", sym->name,
                                 addr - map__unmap_ip(map, sym->start));
                else
                        snprintf(buf, sizeof(buf), "%#" PRIx64 "", addr);
                printf(" %-34s |", buf);

                printf(" %9llu/%-5lu | %9llu/%-5lu | %8lu | %9lu | %6.3f%%\n",
                       (unsigned long long)data->bytes_alloc,
                       (unsigned long)data->bytes_alloc / data->hit,
                       (unsigned long long)data->bytes_req,
                       (unsigned long)data->bytes_req / data->hit,
                       (unsigned long)data->hit,
                       (unsigned long)data->pingpong,
                       fragmentation(data->bytes_req, data->bytes_alloc));

                next = rb_next(next);
        }

        if (n_lines == -1)
                printf(" ...                                | ...             | ...             | ...      | ...       | ...   \n");

        printf("%.105s\n", graph_dotted_line);
}

static const char * const migrate_type_str[] = {
        "UNMOVABL",
        "RECLAIM",
        "MOVABLE",
        "RESERVED",
        "CMA/ISLT",
        "UNKNOWN",
};

static void __print_page_alloc_result(struct perf_session *session, int n_lines)
{
        struct rb_node *next = rb_first(&page_alloc_sorted);
        struct machine *machine = &session->machines.host;
        const char *format;
        int gfp_len = max(strlen("GFP flags"), max_gfp_len);

        printf("\n%.105s\n", graph_dotted_line);
        printf(" %-16s | %5s alloc (KB) | Hits      | Order | Mig.type | %-*s | Callsite\n",
               use_pfn ? "PFN" : "Page", live_page ? "Live" : "Total",
               gfp_len, "GFP flags");
        printf("%.105s\n", graph_dotted_line);

        if (use_pfn)
                format = " %16llu | %'16llu | %'9d | %5d | %8s | %-*s | %s\n";
        else
                format = " %016llx | %'16llu | %'9d | %5d | %8s | %-*s | %s\n";

        while (next && n_lines--) {
                struct page_stat *data;
                struct symbol *sym;
                struct map *map;
                char buf[32];
                char *caller = buf;

                data = rb_entry(next, struct page_stat, node);
                sym = machine__find_kernel_symbol(machine, data->callsite, &map);
                if (sym)
                        caller = sym->name;
                else
                        scnprintf(buf, sizeof(buf), "%"PRIx64, data->callsite);

                printf(format, (unsigned long long)data->page,
                       (unsigned long long)data->alloc_bytes / 1024,
                       data->nr_alloc, data->order,
                       migrate_type_str[data->migrate_type],
                       gfp_len, compact_gfp_string(data->gfp_flags), caller);

                next = rb_next(next);
        }

        if (n_lines == -1) {
                printf(" ...              | ...              | ...       | ...   | ...      | %-*s | ...\n",
                       gfp_len, "...");
        }

        printf("%.105s\n", graph_dotted_line);
}

static void __print_page_caller_result(struct perf_session *session, int n_lines)
{
        struct rb_node *next = rb_first(&page_caller_sorted);
        struct machine *machine = &session->machines.host;
        int gfp_len = max(strlen("GFP flags"), max_gfp_len);

        printf("\n%.105s\n", graph_dotted_line);
        printf(" %5s alloc (KB) | Hits      | Order | Mig.type | %-*s | Callsite\n",
               live_page ? "Live" : "Total", gfp_len, "GFP flags");
        printf("%.105s\n", graph_dotted_line);

        while (next && n_lines--) {
                struct page_stat *data;
                struct symbol *sym;
                struct map *map;
                char buf[32];
                char *caller = buf;

                data = rb_entry(next, struct page_stat, node);
                sym = machine__find_kernel_symbol(machine, data->callsite, &map);
                if (sym)
                        caller = sym->name;
                else
                        scnprintf(buf, sizeof(buf), "%"PRIx64, data->callsite);

                printf(" %'16llu | %'9d | %5d | %8s | %-*s | %s\n",
                       (unsigned long long)data->alloc_bytes / 1024,
                       data->nr_alloc, data->order,
                       migrate_type_str[data->migrate_type],
                       gfp_len, compact_gfp_string(data->gfp_flags), caller);

                next = rb_next(next);
        }

        if (n_lines == -1) {
                printf(" ...              | ...       | ...   | ...      | %-*s | ...\n",
                       gfp_len, "...");
        }

        printf("%.105s\n", graph_dotted_line);
}

static void print_gfp_flags(void)
{
        int i;

        printf("#\n");
        printf("# GFP flags\n");
        printf("# ---------\n");
        for (i = 0; i < nr_gfps; i++) {
                printf("# %08x: %*s: %s\n", gfps[i].flags,
                       (int) max_gfp_len, gfps[i].compact_str,
                       gfps[i].human_readable);
        }
}

static void print_slab_summary(void)
{
        printf("\nSUMMARY (SLAB allocator)");
        printf("\n========================\n");
        printf("Total bytes requested: %'lu\n", total_requested);
        printf("Total bytes allocated: %'lu\n", total_allocated);
        printf("Total bytes freed:     %'lu\n", total_freed);
        if (total_allocated > total_freed) {
                printf("Net total bytes allocated: %'lu\n",
                total_allocated - total_freed);
        }
        printf("Total bytes wasted on internal fragmentation: %'lu\n",
               total_allocated - total_requested);
        printf("Internal fragmentation: %f%%\n",
               fragmentation(total_requested, total_allocated));
        printf("Cross CPU allocations: %'lu/%'lu\n", nr_cross_allocs, nr_allocs);
}

static void print_page_summary(void)
{
        int o, m;
        u64 nr_alloc_freed = nr_page_frees - nr_page_nomatch;
        u64 total_alloc_freed_bytes = total_page_free_bytes - total_page_nomatch_bytes;

        printf("\nSUMMARY (page allocator)");
        printf("\n========================\n");
        printf("%-30s: %'16lu   [ %'16"PRIu64" KB ]\n", "Total allocation requests",
               nr_page_allocs, total_page_alloc_bytes / 1024);
        printf("%-30s: %'16lu   [ %'16"PRIu64" KB ]\n", "Total free requests",
               nr_page_frees, total_page_free_bytes / 1024);
        printf("\n");

        printf("%-30s: %'16"PRIu64"   [ %'16"PRIu64" KB ]\n", "Total alloc+freed requests",
               nr_alloc_freed, (total_alloc_freed_bytes) / 1024);
        printf("%-30s: %'16"PRIu64"   [ %'16"PRIu64" KB ]\n", "Total alloc-only requests",
               nr_page_allocs - nr_alloc_freed,
               (total_page_alloc_bytes - total_alloc_freed_bytes) / 1024);
        printf("%-30s: %'16lu   [ %'16"PRIu64" KB ]\n", "Total free-only requests",
               nr_page_nomatch, total_page_nomatch_bytes / 1024);
        printf("\n");

        printf("%-30s: %'16lu   [ %'16"PRIu64" KB ]\n", "Total allocation failures",
               nr_page_fails, total_page_fail_bytes / 1024);
        printf("\n");

        printf("%5s  %12s  %12s  %12s  %12s  %12s\n", "Order",  "Unmovable",
               "Reclaimable", "Movable", "Reserved", "CMA/Isolated");
        printf("%.5s  %.12s  %.12s  %.12s  %.12s  %.12s\n", graph_dotted_line,
               graph_dotted_line, graph_dotted_line, graph_dotted_line,
               graph_dotted_line, graph_dotted_line);

        for (o = 0; o < MAX_PAGE_ORDER; o++) {
                printf("%5d", o);
                for (m = 0; m < MAX_MIGRATE_TYPES - 1; m++) {
                        if (order_stats[o][m])
                                printf("  %'12d", order_stats[o][m]);
                        else
                                printf("  %12c", '.');
                }
                printf("\n");
        }
}

static void print_slab_result(struct perf_session *session)
{
        if (caller_flag)
                __print_slab_result(&root_caller_sorted, session, caller_lines, 1);
        if (alloc_flag)
                __print_slab_result(&root_alloc_sorted, session, alloc_lines, 0);
        print_slab_summary();
}

static void print_page_result(struct perf_session *session)
{
        if (caller_flag || alloc_flag)
                print_gfp_flags();
        if (caller_flag)
                __print_page_caller_result(session, caller_lines);
        if (alloc_flag)
                __print_page_alloc_result(session, alloc_lines);
        print_page_summary();
}

static void print_result(struct perf_session *session)
{
        if (kmem_slab)
                print_slab_result(session);
        if (kmem_page)
                print_page_result(session);
}

static LIST_HEAD(slab_caller_sort);
static LIST_HEAD(slab_alloc_sort);
static LIST_HEAD(page_caller_sort);
static LIST_HEAD(page_alloc_sort);

static void sort_slab_insert(struct rb_root *root, struct alloc_stat *data,
                             struct list_head *sort_list)
{
        struct rb_node **new = &(root->rb_node);
        struct rb_node *parent = NULL;
        struct sort_dimension *sort;

        while (*new) {
                struct alloc_stat *this;
                int cmp = 0;

                this = rb_entry(*new, struct alloc_stat, node);
                parent = *new;

                list_for_each_entry(sort, sort_list, list) {
                        cmp = sort->cmp(data, this);
                        if (cmp)
                                break;
                }

                if (cmp > 0)
                        new = &((*new)->rb_left);
                else
                        new = &((*new)->rb_right);
        }

        rb_link_node(&data->node, parent, new);
        rb_insert_color(&data->node, root);
}

static void __sort_slab_result(struct rb_root *root, struct rb_root *root_sorted,
                               struct list_head *sort_list)
{
        struct rb_node *node;
        struct alloc_stat *data;

        for (;;) {
                node = rb_first(root);
                if (!node)
                        break;

                rb_erase(node, root);
                data = rb_entry(node, struct alloc_stat, node);
                sort_slab_insert(root_sorted, data, sort_list);
        }
}

static void sort_page_insert(struct rb_root *root, struct page_stat *data,
                             struct list_head *sort_list)
{
        struct rb_node **new = &root->rb_node;
        struct rb_node *parent = NULL;
        struct sort_dimension *sort;

        while (*new) {
                struct page_stat *this;
                int cmp = 0;

                this = rb_entry(*new, struct page_stat, node);
                parent = *new;

                list_for_each_entry(sort, sort_list, list) {
                        cmp = sort->cmp(data, this);
                        if (cmp)
                                break;
                }

                if (cmp > 0)
                        new = &parent->rb_left;
                else
                        new = &parent->rb_right;
        }

        rb_link_node(&data->node, parent, new);
        rb_insert_color(&data->node, root);
}

static void __sort_page_result(struct rb_root *root, struct rb_root *root_sorted,
                               struct list_head *sort_list)
{
        struct rb_node *node;
        struct page_stat *data;

        for (;;) {
                node = rb_first(root);
                if (!node)
                        break;

                rb_erase(node, root);
                data = rb_entry(node, struct page_stat, node);
                sort_page_insert(root_sorted, data, sort_list);
        }
}

static void sort_result(void)
{
        if (kmem_slab) {
                __sort_slab_result(&root_alloc_stat, &root_alloc_sorted,
                                   &slab_alloc_sort);
                __sort_slab_result(&root_caller_stat, &root_caller_sorted,
                                   &slab_caller_sort);
        }
        if (kmem_page) {
                if (live_page)
                        __sort_page_result(&page_live_tree, &page_alloc_sorted,
                                           &page_alloc_sort);
                else
                        __sort_page_result(&page_alloc_tree, &page_alloc_sorted,
                                           &page_alloc_sort);

                __sort_page_result(&page_caller_tree, &page_caller_sorted,
                                   &page_caller_sort);
        }
}

static int __cmd_kmem(struct perf_session *session)
{
        int err = -EINVAL;
        struct evsel *evsel;
        const struct evsel_str_handler kmem_tracepoints[] = {
                /* slab allocator */
                { "kmem:kmalloc",               evsel__process_alloc_event, },
                { "kmem:kmem_cache_alloc",      evsel__process_alloc_event, },
                { "kmem:kmalloc_node",          evsel__process_alloc_event, },
                { "kmem:kmem_cache_alloc_node", evsel__process_alloc_event, },
                { "kmem:kfree",                 evsel__process_free_event, },
                { "kmem:kmem_cache_free",       evsel__process_free_event, },
                /* page allocator */
                { "kmem:mm_page_alloc",         evsel__process_page_alloc_event, },
                { "kmem:mm_page_free",          evsel__process_page_free_event, },
        };

        if (!perf_session__has_traces(session, "kmem record"))
                goto out;

        if (perf_session__set_tracepoints_handlers(session, kmem_tracepoints)) {
                pr_err("Initializing perf session tracepoint handlers failed\n");
                goto out;
        }

        evlist__for_each_entry(session->evlist, evsel) {
                if (evsel__name_is(evsel, "kmem:mm_page_alloc") &&
                    evsel__field(evsel, "pfn")) {
                        use_pfn = true;
                        break;
                }
        }

        setup_pager();
        err = perf_session__process_events(session);
        if (err != 0) {
                pr_err("error during process events: %d\n", err);
                goto out;
        }
        sort_result();
        print_result(session);
out:
        return err;
}

/* slab sort keys */
static int ptr_cmp(void *a, void *b)
{
        struct alloc_stat *l = a;
        struct alloc_stat *r = b;

        if (l->ptr < r->ptr)
                return -1;
        else if (l->ptr > r->ptr)
                return 1;
        return 0;
}

static struct sort_dimension ptr_sort_dimension = {
        .name   = "ptr",
        .cmp    = ptr_cmp,
};

static int slab_callsite_cmp(void *a, void *b)
{
        struct alloc_stat *l = a;
        struct alloc_stat *r = b;

        if (l->call_site < r->call_site)
                return -1;
        else if (l->call_site > r->call_site)
                return 1;
        return 0;
}

static struct sort_dimension callsite_sort_dimension = {
        .name   = "callsite",
        .cmp    = slab_callsite_cmp,
};

static int hit_cmp(void *a, void *b)
{
        struct alloc_stat *l = a;
        struct alloc_stat *r = b;

        if (l->hit < r->hit)
                return -1;
        else if (l->hit > r->hit)
                return 1;
        return 0;
}

static struct sort_dimension hit_sort_dimension = {
        .name   = "hit",
        .cmp    = hit_cmp,
};

static int bytes_cmp(void *a, void *b)
{
        struct alloc_stat *l = a;
        struct alloc_stat *r = b;

        if (l->bytes_alloc < r->bytes_alloc)
                return -1;
        else if (l->bytes_alloc > r->bytes_alloc)
                return 1;
        return 0;
}

static struct sort_dimension bytes_sort_dimension = {
        .name   = "bytes",
        .cmp    = bytes_cmp,
};

static int frag_cmp(void *a, void *b)
{
        double x, y;
        struct alloc_stat *l = a;
        struct alloc_stat *r = b;

        x = fragmentation(l->bytes_req, l->bytes_alloc);
        y = fragmentation(r->bytes_req, r->bytes_alloc);

        if (x < y)
                return -1;
        else if (x > y)
                return 1;
        return 0;
}

static struct sort_dimension frag_sort_dimension = {
        .name   = "frag",
        .cmp    = frag_cmp,
};

static int pingpong_cmp(void *a, void *b)
{
        struct alloc_stat *l = a;
        struct alloc_stat *r = b;

        if (l->pingpong < r->pingpong)
                return -1;
        else if (l->pingpong > r->pingpong)
                return 1;
        return 0;
}

static struct sort_dimension pingpong_sort_dimension = {
        .name   = "pingpong",
        .cmp    = pingpong_cmp,
};

/* page sort keys */
static int page_cmp(void *a, void *b)
{
        struct page_stat *l = a;
        struct page_stat *r = b;

        if (l->page < r->page)
                return -1;
        else if (l->page > r->page)
                return 1;
        return 0;
}

static struct sort_dimension page_sort_dimension = {
        .name   = "page",
        .cmp    = page_cmp,
};

static int page_callsite_cmp(void *a, void *b)
{
        struct page_stat *l = a;
        struct page_stat *r = b;

        if (l->callsite < r->callsite)
                return -1;
        else if (l->callsite > r->callsite)
                return 1;
        return 0;
}

static struct sort_dimension page_callsite_sort_dimension = {
        .name   = "callsite",
        .cmp    = page_callsite_cmp,
};

static int page_hit_cmp(void *a, void *b)
{
        struct page_stat *l = a;
        struct page_stat *r = b;

        if (l->nr_alloc < r->nr_alloc)
                return -1;
        else if (l->nr_alloc > r->nr_alloc)
                return 1;
        return 0;
}

static struct sort_dimension page_hit_sort_dimension = {
        .name   = "hit",
        .cmp    = page_hit_cmp,
};

static int page_bytes_cmp(void *a, void *b)
{
        struct page_stat *l = a;
        struct page_stat *r = b;

        if (l->alloc_bytes < r->alloc_bytes)
                return -1;
        else if (l->alloc_bytes > r->alloc_bytes)
                return 1;
        return 0;
}

static struct sort_dimension page_bytes_sort_dimension = {
        .name   = "bytes",
        .cmp    = page_bytes_cmp,
};

static int page_order_cmp(void *a, void *b)
{
        struct page_stat *l = a;
        struct page_stat *r = b;

        if (l->order < r->order)
                return -1;
        else if (l->order > r->order)
                return 1;
        return 0;
}

static struct sort_dimension page_order_sort_dimension = {
        .name   = "order",
        .cmp    = page_order_cmp,
};

static int migrate_type_cmp(void *a, void *b)
{
        struct page_stat *l = a;
        struct page_stat *r = b;

        /* for internal use to find free'd page */
        if (l->migrate_type == -1U)
                return 0;

        if (l->migrate_type < r->migrate_type)
                return -1;
        else if (l->migrate_type > r->migrate_type)
                return 1;
        return 0;
}

static struct sort_dimension migrate_type_sort_dimension = {
        .name   = "migtype",
        .cmp    = migrate_type_cmp,
};

static int gfp_flags_cmp(void *a, void *b)
{
        struct page_stat *l = a;
        struct page_stat *r = b;

        /* for internal use to find free'd page */
        if (l->gfp_flags == -1U)
                return 0;

        if (l->gfp_flags < r->gfp_flags)
                return -1;
        else if (l->gfp_flags > r->gfp_flags)
                return 1;
        return 0;
}

static struct sort_dimension gfp_flags_sort_dimension = {
        .name   = "gfp",
        .cmp    = gfp_flags_cmp,
};

static struct sort_dimension *slab_sorts[] = {
        &ptr_sort_dimension,
        &callsite_sort_dimension,
        &hit_sort_dimension,
        &bytes_sort_dimension,
        &frag_sort_dimension,
        &pingpong_sort_dimension,
};

static struct sort_dimension *page_sorts[] = {
        &page_sort_dimension,
        &page_callsite_sort_dimension,
        &page_hit_sort_dimension,
        &page_bytes_sort_dimension,
        &page_order_sort_dimension,
        &migrate_type_sort_dimension,
        &gfp_flags_sort_dimension,
};

static int slab_sort_dimension__add(const char *tok, struct list_head *list)
{
        struct sort_dimension *sort;
        int i;

        for (i = 0; i < (int)ARRAY_SIZE(slab_sorts); i++) {
                if (!strcmp(slab_sorts[i]->name, tok)) {
                        sort = memdup(slab_sorts[i], sizeof(*slab_sorts[i]));
                        if (!sort) {
                                pr_err("%s: memdup failed\n", __func__);
                                return -1;
                        }
                        list_add_tail(&sort->list, list);
                        return 0;
                }
        }

        return -1;
}

static int page_sort_dimension__add(const char *tok, struct list_head *list)
{
        struct sort_dimension *sort;
        int i;

        for (i = 0; i < (int)ARRAY_SIZE(page_sorts); i++) {
                if (!strcmp(page_sorts[i]->name, tok)) {
                        sort = memdup(page_sorts[i], sizeof(*page_sorts[i]));
                        if (!sort) {
                                pr_err("%s: memdup failed\n", __func__);
                                return -1;
                        }
                        list_add_tail(&sort->list, list);
                        return 0;
                }
        }

        return -1;
}

static int setup_slab_sorting(struct list_head *sort_list, const char *arg)
{
        char *tok;
        char *str = strdup(arg);
        char *pos = str;

        if (!str) {
                pr_err("%s: strdup failed\n", __func__);
                return -1;
        }

        while (true) {
                tok = strsep(&pos, ",");
                if (!tok)
                        break;
                if (slab_sort_dimension__add(tok, sort_list) < 0) {
                        pr_err("Unknown slab --sort key: '%s'", tok);
                        free(str);
                        return -1;
                }
        }

        free(str);
        return 0;
}

static int setup_page_sorting(struct list_head *sort_list, const char *arg)
{
        char *tok;
        char *str = strdup(arg);
        char *pos = str;

        if (!str) {
                pr_err("%s: strdup failed\n", __func__);
                return -1;
        }

        while (true) {
                tok = strsep(&pos, ",");
                if (!tok)
                        break;
                if (page_sort_dimension__add(tok, sort_list) < 0) {
                        pr_err("Unknown page --sort key: '%s'", tok);
                        free(str);
                        return -1;
                }
        }

        free(str);
        return 0;
}

static int parse_sort_opt(const struct option *opt __maybe_unused,
                          const char *arg, int unset __maybe_unused)
{
        if (!arg)
                return -1;

        if (kmem_page > kmem_slab ||
            (kmem_page == 0 && kmem_slab == 0 && kmem_default == KMEM_PAGE)) {
                if (caller_flag > alloc_flag)
                        return setup_page_sorting(&page_caller_sort, arg);
                else
                        return setup_page_sorting(&page_alloc_sort, arg);
        } else {
                if (caller_flag > alloc_flag)
                        return setup_slab_sorting(&slab_caller_sort, arg);
                else
                        return setup_slab_sorting(&slab_alloc_sort, arg);
        }

        return 0;
}

static int parse_caller_opt(const struct option *opt __maybe_unused,
                            const char *arg __maybe_unused,
                            int unset __maybe_unused)
{
        caller_flag = (alloc_flag + 1);
        return 0;
}

static int parse_alloc_opt(const struct option *opt __maybe_unused,
                           const char *arg __maybe_unused,
                           int unset __maybe_unused)
{
        alloc_flag = (caller_flag + 1);
        return 0;
}

static int parse_slab_opt(const struct option *opt __maybe_unused,
                          const char *arg __maybe_unused,
                          int unset __maybe_unused)
{
        kmem_slab = (kmem_page + 1);
        return 0;
}

static int parse_page_opt(const struct option *opt __maybe_unused,
                          const char *arg __maybe_unused,
                          int unset __maybe_unused)
{
        kmem_page = (kmem_slab + 1);
        return 0;
}

static int parse_line_opt(const struct option *opt __maybe_unused,
                          const char *arg, int unset __maybe_unused)
{
        int lines;

        if (!arg)
                return -1;

        lines = strtoul(arg, NULL, 10);

        if (caller_flag > alloc_flag)
                caller_lines = lines;
        else
                alloc_lines = lines;

        return 0;
}

static bool slab_legacy_tp_is_exposed(void)
{
        /*
         * The tracepoints "kmem:kmalloc_node" and
         * "kmem:kmem_cache_alloc_node" have been removed on the latest
         * kernel, if the tracepoint "kmem:kmalloc_node" is existed it
         * means the tool is running on an old kernel, we need to
         * rollback to support these legacy tracepoints.
         */
        return IS_ERR(trace_event__tp_format("kmem", "kmalloc_node")) ?
                false : true;
}

static int __cmd_record(int argc, const char **argv)
{
        const char * const record_args[] = {
        "record", "-a", "-R", "-c", "1",
        };
        const char * const slab_events[] = {
        "-e", "kmem:kmalloc",
        "-e", "kmem:kfree",
        "-e", "kmem:kmem_cache_alloc",
        "-e", "kmem:kmem_cache_free",
        };
        const char * const slab_legacy_events[] = {
        "-e", "kmem:kmalloc_node",
        "-e", "kmem:kmem_cache_alloc_node",
        };
        const char * const page_events[] = {
        "-e", "kmem:mm_page_alloc",
        "-e", "kmem:mm_page_free",
        };
        unsigned int rec_argc, i, j;
        const char **rec_argv;
        unsigned int slab_legacy_tp_exposed = slab_legacy_tp_is_exposed();

        rec_argc = ARRAY_SIZE(record_args) + argc - 1;
        if (kmem_slab) {
                rec_argc += ARRAY_SIZE(slab_events);
                if (slab_legacy_tp_exposed)
                        rec_argc += ARRAY_SIZE(slab_legacy_events);
        }
        if (kmem_page)
                rec_argc += ARRAY_SIZE(page_events) + 1; /* for -g */

        rec_argv = calloc(rec_argc + 1, sizeof(char *));

        if (rec_argv == NULL)
                return -ENOMEM;

        for (i = 0; i < ARRAY_SIZE(record_args); i++)
                rec_argv[i] = strdup(record_args[i]);

        if (kmem_slab) {
                for (j = 0; j < ARRAY_SIZE(slab_events); j++, i++)
                        rec_argv[i] = strdup(slab_events[j]);
                if (slab_legacy_tp_exposed) {
                        for (j = 0; j < ARRAY_SIZE(slab_legacy_events); j++, i++)
                                rec_argv[i] = strdup(slab_legacy_events[j]);
                }
        }
        if (kmem_page) {
                rec_argv[i++] = strdup("-g");

                for (j = 0; j < ARRAY_SIZE(page_events); j++, i++)
                        rec_argv[i] = strdup(page_events[j]);
        }

        for (j = 1; j < (unsigned int)argc; j++, i++)
                rec_argv[i] = argv[j];

        return cmd_record(i, rec_argv);
}

static int kmem_config(const char *var, const char *value, void *cb __maybe_unused)
{
        if (!strcmp(var, "kmem.default")) {
                if (!strcmp(value, "slab"))
                        kmem_default = KMEM_SLAB;
                else if (!strcmp(value, "page"))
                        kmem_default = KMEM_PAGE;
                else
                        pr_err("invalid default value ('slab' or 'page' required): %s\n",
                               value);
                return 0;
        }

        return 0;
}

int cmd_kmem(int argc, const char **argv)
{
        const char * const default_slab_sort = "frag,hit,bytes";
        const char * const default_page_sort = "bytes,hit";
        struct perf_data data = {
                .mode = PERF_DATA_MODE_READ,
        };
        const struct option kmem_options[] = {
        OPT_STRING('i', "input", &input_name, "file", "input file name"),
        OPT_INCR('v', "verbose", &verbose,
                    "be more verbose (show symbol address, etc)"),
        OPT_CALLBACK_NOOPT(0, "caller", NULL, NULL,
                           "show per-callsite statistics", parse_caller_opt),
        OPT_CALLBACK_NOOPT(0, "alloc", NULL, NULL,
                           "show per-allocation statistics", parse_alloc_opt),
        OPT_CALLBACK('s', "sort", NULL, "key[,key2...]",
                     "sort by keys: ptr, callsite, bytes, hit, pingpong, frag, "
                     "page, order, migtype, gfp", parse_sort_opt),
        OPT_CALLBACK('l', "line", NULL, "num", "show n lines", parse_line_opt),
        OPT_BOOLEAN(0, "raw-ip", &raw_ip, "show raw ip instead of symbol"),
        OPT_BOOLEAN('f', "force", &data.force, "don't complain, do it"),
        OPT_CALLBACK_NOOPT(0, "slab", NULL, NULL, "Analyze slab allocator",
                           parse_slab_opt),
        OPT_CALLBACK_NOOPT(0, "page", NULL, NULL, "Analyze page allocator",
                           parse_page_opt),
        OPT_BOOLEAN(0, "live", &live_page, "Show live page stat"),
        OPT_STRING(0, "time", &time_str, "str",
                   "Time span of interest (start,stop)"),
        OPT_END()
        };
        const char *const kmem_subcommands[] = { "record", "stat", NULL };
        const char *kmem_usage[] = {
                NULL,
                NULL
        };
        struct perf_session *session;
        struct perf_tool perf_kmem;
        static const char errmsg[] = "No %s allocation events found.  Have you run 'perf kmem record --%s'?\n";
        int ret = perf_config(kmem_config, NULL);

        if (ret)
                return ret;

        argc = parse_options_subcommand(argc, argv, kmem_options,
                                        kmem_subcommands, kmem_usage,
                                        PARSE_OPT_STOP_AT_NON_OPTION);

        if (!argc)
                usage_with_options(kmem_usage, kmem_options);

        if (kmem_slab == 0 && kmem_page == 0) {
                if (kmem_default == KMEM_SLAB)
                        kmem_slab = 1;
                else
                        kmem_page = 1;
        }

        if (strlen(argv[0]) > 2 && strstarts("record", argv[0])) {
                symbol__init(NULL);
                return __cmd_record(argc, argv);
        }

        data.path = input_name;

        perf_tool__init(&perf_kmem, /*ordered_events=*/true);
        perf_kmem.sample        = process_sample_event;
        perf_kmem.comm          = perf_event__process_comm;
        perf_kmem.mmap          = perf_event__process_mmap;
        perf_kmem.mmap2         = perf_event__process_mmap2;
        perf_kmem.namespaces    = perf_event__process_namespaces;

        kmem_session = session = perf_session__new(&data, &perf_kmem);
        if (IS_ERR(session))
                return PTR_ERR(session);

        ret = -1;

        if (kmem_slab) {
                if (!evlist__find_tracepoint_by_name(session->evlist, "kmem:kmalloc")) {
                        pr_err(errmsg, "slab", "slab");
                        goto out_delete;
                }
        }

        if (kmem_page) {
                struct evsel *evsel = evlist__find_tracepoint_by_name(session->evlist, "kmem:mm_page_alloc");
                const struct tep_event *tp_format = evsel ? evsel__tp_format(evsel) : NULL;

                if (tp_format == NULL) {
                        pr_err(errmsg, "page", "page");
                        goto out_delete;
                }
                kmem_page_size = tep_get_page_size(tp_format->tep);
                symbol_conf.use_callchain = true;
        }

        symbol__init(perf_session__env(session));

        if (perf_time__parse_str(&ptime, time_str) != 0) {
                pr_err("Invalid time string\n");
                ret = -EINVAL;
                goto out_delete;
        }

        if (!strcmp(argv[0], "stat")) {
                setlocale(LC_ALL, "");

                if (cpu__setup_cpunode_map())
                        goto out_delete;

                if (list_empty(&slab_caller_sort))
                        setup_slab_sorting(&slab_caller_sort, default_slab_sort);
                if (list_empty(&slab_alloc_sort))
                        setup_slab_sorting(&slab_alloc_sort, default_slab_sort);
                if (list_empty(&page_caller_sort))
                        setup_page_sorting(&page_caller_sort, default_page_sort);
                if (list_empty(&page_alloc_sort))
                        setup_page_sorting(&page_alloc_sort, default_page_sort);

                if (kmem_page) {
                        setup_page_sorting(&page_alloc_sort_input,
                                           "page,order,migtype,gfp");
                        setup_page_sorting(&page_caller_sort_input,
                                           "callsite,order,migtype,gfp");
                }
                ret = __cmd_kmem(session);
        } else
                usage_with_options(kmem_usage, kmem_options);

out_delete:
        perf_session__delete(session);
        /* free usage string allocated by parse_options_subcommand */
        free((void *)kmem_usage[0]);

        return ret;
}