From patchwork Tue Apr 6 12:25:59 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Faiyaz Mohammed X-Patchwork-Id: 12185175 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-16.6 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 7FC65C433ED for ; Tue, 6 Apr 2021 12:26:42 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id DA3706139E for ; Tue, 6 Apr 2021 12:26:41 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org DA3706139E Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=codeaurora.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 5657A6B007E; Tue, 6 Apr 2021 08:26:41 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 515D46B0080; Tue, 6 Apr 2021 08:26:41 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 367D56B0081; Tue, 6 Apr 2021 08:26:41 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0219.hostedemail.com [216.40.44.219]) by kanga.kvack.org (Postfix) with ESMTP id 174A86B007E for ; Tue, 6 Apr 2021 08:26:41 -0400 (EDT) Received: from smtpin09.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay01.hostedemail.com (Postfix) with ESMTP id BC85F180ACEE4 for ; Tue, 6 Apr 2021 12:26:40 +0000 (UTC) X-FDA: 78001865760.09.48007A7 Received: from m43-7.mailgun.net (m43-7.mailgun.net [69.72.43.7]) by imf23.hostedemail.com (Postfix) with ESMTP id 42E0AA000382 for ; Tue, 6 Apr 2021 12:26:37 +0000 (UTC) DKIM-Signature: a=rsa-sha256; v=1; c=relaxed/relaxed; d=mg.codeaurora.org; q=dns/txt; s=smtp; t=1617712000; h=Message-Id: Date: Subject: Cc: To: From: Sender; bh=qGvFg0vtqKWMNlOyiMyaboiua5Csfjf0wXj4RSrrAec=; b=cjyQF0PF23ush2MQaL2mYHFygsXRbK99ykDNjbLQBhKBAKVF2oeX8qRRObKf257i7k1v0UIO c2wviZ61LBL2nfxL1hUrfew+DFz1oN9Z6uvEnYxr7jLL8s/YwAqeD//yai5S87sfgjsHLq44 lOjwh36i4U/13g9PgYw219P+YJ0= X-Mailgun-Sending-Ip: 69.72.43.7 X-Mailgun-Sid: WyIwY2Q3OCIsICJsaW51eC1tbUBrdmFjay5vcmciLCAiYmU5ZTRhIl0= Received: from smtp.codeaurora.org (ec2-35-166-182-171.us-west-2.compute.amazonaws.com [35.166.182.171]) by smtp-out-n07.prod.us-west-2.postgun.com with SMTP id 606c5367e0e9c9a6b67b159d (version=TLS1.2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256); Tue, 06 Apr 2021 12:26:15 GMT Received: by smtp.codeaurora.org (Postfix, from userid 1001) id A196EC433ED; Tue, 6 Apr 2021 12:26:15 +0000 (UTC) Received: from faiyazm-linux.qualcomm.com (unknown [202.46.22.19]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-SHA256 (128/128 bits)) (No client certificate requested) (Authenticated sender: faiyazm) by smtp.codeaurora.org (Postfix) with ESMTPSA id 11CD2C433CA; Tue, 6 Apr 2021 12:26:10 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 smtp.codeaurora.org 11CD2C433CA Authentication-Results: aws-us-west-2-caf-mail-1.web.codeaurora.org; dmarc=none (p=none dis=none) header.from=codeaurora.org Authentication-Results: aws-us-west-2-caf-mail-1.web.codeaurora.org; spf=fail smtp.mailfrom=faiyazm@codeaurora.org From: Faiyaz Mohammed To: cl@linux.com, penberg@kernel.org, rientjes@google.com, iamjoonsoo.kim@lge.com, akpm@linux-foundation.org, vbabka@suse.cz, linux-mm@kvack.org, linux-kernel@vger.kernel.org Cc: Faiyaz Mohammed Subject: [PATCH] mm: slub: move sysfs slab alloc/free interfaces to debugfs Date: Tue, 6 Apr 2021 17:55:59 +0530 Message-Id: <1617711959-11146-1-git-send-email-faiyazm@codeaurora.org> X-Mailer: git-send-email 2.7.4 X-Stat-Signature: rg1da6p777xnb366ypcq7ocz7sc8jjna X-Rspamd-Server: rspam04 X-Rspamd-Queue-Id: 42E0AA000382 Received-SPF: none (mg.codeaurora.org>: No applicable sender policy available) receiver=imf23; identity=mailfrom; envelope-from=""; helo=m43-7.mailgun.net; client-ip=69.72.43.7 X-HE-DKIM-Result: pass/pass X-HE-Tag: 1617711997-832297 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: alloc_calls and free_calls implementation in sysfs have two issues, one is PAGE_SIZE limitiation of sysfs and other is it does not adhere to "one value per file" rule. To overcome this issues, move the alloc_calls and free_calls implemeation to debugfs. Signed-off-by: Faiyaz Mohammed --- mm/slub.c | 518 ++++++++++++++++++++++++++++++++++---------------------------- 1 file changed, 286 insertions(+), 232 deletions(-) diff --git a/mm/slub.c b/mm/slub.c index 3021ce9..4d20ee0 100644 --- a/mm/slub.c +++ b/mm/slub.c @@ -36,6 +36,7 @@ #include #include +#include #include #include "internal.h" @@ -225,6 +226,12 @@ static inline int sysfs_slab_alias(struct kmem_cache *s, const char *p) { return 0; } #endif +#ifdef CONFIG_DEBUG_FS +static void debugfs_slab_add(struct kmem_cache *); +#else +static inline void debugfs_slab_add(struct kmem_cache *) { } +#endif + static inline void stat(const struct kmem_cache *s, enum stat_item si) { #ifdef CONFIG_SLUB_STATS @@ -4542,6 +4549,8 @@ int __kmem_cache_create(struct kmem_cache *s, slab_flags_t flags) if (err) __kmem_cache_release(s); + debugfs_slab_add(s); + return err; } @@ -4682,221 +4691,6 @@ static long validate_slab_cache(struct kmem_cache *s) return count; } -/* - * Generate lists of code addresses where slabcache objects are allocated - * and freed. - */ - -struct location { - unsigned long count; - unsigned long addr; - long long sum_time; - long min_time; - long max_time; - long min_pid; - long max_pid; - DECLARE_BITMAP(cpus, NR_CPUS); - nodemask_t nodes; -}; - -struct loc_track { - unsigned long max; - unsigned long count; - struct location *loc; -}; - -static void free_loc_track(struct loc_track *t) -{ - if (t->max) - free_pages((unsigned long)t->loc, - get_order(sizeof(struct location) * t->max)); -} - -static int alloc_loc_track(struct loc_track *t, unsigned long max, gfp_t flags) -{ - struct location *l; - int order; - - order = get_order(sizeof(struct location) * max); - - l = (void *)__get_free_pages(flags, order); - if (!l) - return 0; - - if (t->count) { - memcpy(l, t->loc, sizeof(struct location) * t->count); - free_loc_track(t); - } - t->max = max; - t->loc = l; - return 1; -} - -static int add_location(struct loc_track *t, struct kmem_cache *s, - const struct track *track) -{ - long start, end, pos; - struct location *l; - unsigned long caddr; - unsigned long age = jiffies - track->when; - - start = -1; - end = t->count; - - for ( ; ; ) { - pos = start + (end - start + 1) / 2; - - /* - * There is nothing at "end". If we end up there - * we need to add something to before end. - */ - if (pos == end) - break; - - caddr = t->loc[pos].addr; - if (track->addr == caddr) { - - l = &t->loc[pos]; - l->count++; - if (track->when) { - l->sum_time += age; - if (age < l->min_time) - l->min_time = age; - if (age > l->max_time) - l->max_time = age; - - if (track->pid < l->min_pid) - l->min_pid = track->pid; - if (track->pid > l->max_pid) - l->max_pid = track->pid; - - cpumask_set_cpu(track->cpu, - to_cpumask(l->cpus)); - } - node_set(page_to_nid(virt_to_page(track)), l->nodes); - return 1; - } - - if (track->addr < caddr) - end = pos; - else - start = pos; - } - - /* - * Not found. Insert new tracking element. - */ - if (t->count >= t->max && !alloc_loc_track(t, 2 * t->max, GFP_ATOMIC)) - return 0; - - l = t->loc + pos; - if (pos < t->count) - memmove(l + 1, l, - (t->count - pos) * sizeof(struct location)); - t->count++; - l->count = 1; - l->addr = track->addr; - l->sum_time = age; - l->min_time = age; - l->max_time = age; - l->min_pid = track->pid; - l->max_pid = track->pid; - cpumask_clear(to_cpumask(l->cpus)); - cpumask_set_cpu(track->cpu, to_cpumask(l->cpus)); - nodes_clear(l->nodes); - node_set(page_to_nid(virt_to_page(track)), l->nodes); - return 1; -} - -static void process_slab(struct loc_track *t, struct kmem_cache *s, - struct page *page, enum track_item alloc) -{ - void *addr = page_address(page); - void *p; - unsigned long *map; - - map = get_map(s, page); - for_each_object(p, s, addr, page->objects) - if (!test_bit(__obj_to_index(s, addr, p), map)) - add_location(t, s, get_track(s, p, alloc)); - put_map(map); -} - -static int list_locations(struct kmem_cache *s, char *buf, - enum track_item alloc) -{ - int len = 0; - unsigned long i; - struct loc_track t = { 0, 0, NULL }; - int node; - struct kmem_cache_node *n; - - if (!alloc_loc_track(&t, PAGE_SIZE / sizeof(struct location), - GFP_KERNEL)) { - return sysfs_emit(buf, "Out of memory\n"); - } - /* Push back cpu slabs */ - flush_all(s); - - for_each_kmem_cache_node(s, node, n) { - unsigned long flags; - struct page *page; - - if (!atomic_long_read(&n->nr_slabs)) - continue; - - spin_lock_irqsave(&n->list_lock, flags); - list_for_each_entry(page, &n->partial, slab_list) - process_slab(&t, s, page, alloc); - list_for_each_entry(page, &n->full, slab_list) - process_slab(&t, s, page, alloc); - spin_unlock_irqrestore(&n->list_lock, flags); - } - - for (i = 0; i < t.count; i++) { - struct location *l = &t.loc[i]; - - len += sysfs_emit_at(buf, len, "%7ld ", l->count); - - if (l->addr) - len += sysfs_emit_at(buf, len, "%pS", (void *)l->addr); - else - len += sysfs_emit_at(buf, len, ""); - - if (l->sum_time != l->min_time) - len += sysfs_emit_at(buf, len, " age=%ld/%ld/%ld", - l->min_time, - (long)div_u64(l->sum_time, - l->count), - l->max_time); - else - len += sysfs_emit_at(buf, len, " age=%ld", l->min_time); - - if (l->min_pid != l->max_pid) - len += sysfs_emit_at(buf, len, " pid=%ld-%ld", - l->min_pid, l->max_pid); - else - len += sysfs_emit_at(buf, len, " pid=%ld", - l->min_pid); - - if (num_online_cpus() > 1 && - !cpumask_empty(to_cpumask(l->cpus))) - len += sysfs_emit_at(buf, len, " cpus=%*pbl", - cpumask_pr_args(to_cpumask(l->cpus))); - - if (nr_online_nodes > 1 && !nodes_empty(l->nodes)) - len += sysfs_emit_at(buf, len, " nodes=%*pbl", - nodemask_pr_args(&l->nodes)); - - len += sysfs_emit_at(buf, len, "\n"); - } - - free_loc_track(&t); - if (!t.count) - len += sysfs_emit_at(buf, len, "No data\n"); - - return len; -} #endif /* CONFIG_SLUB_DEBUG */ #ifdef SLUB_RESILIENCY_TEST @@ -5346,21 +5140,6 @@ static ssize_t validate_store(struct kmem_cache *s, } SLAB_ATTR(validate); -static ssize_t alloc_calls_show(struct kmem_cache *s, char *buf) -{ - if (!(s->flags & SLAB_STORE_USER)) - return -ENOSYS; - return list_locations(s, buf, TRACK_ALLOC); -} -SLAB_ATTR_RO(alloc_calls); - -static ssize_t free_calls_show(struct kmem_cache *s, char *buf) -{ - if (!(s->flags & SLAB_STORE_USER)) - return -ENOSYS; - return list_locations(s, buf, TRACK_FREE); -} -SLAB_ATTR_RO(free_calls); #endif /* CONFIG_SLUB_DEBUG */ #ifdef CONFIG_FAILSLAB @@ -5524,8 +5303,6 @@ static struct attribute *slab_attrs[] = { &poison_attr.attr, &store_user_attr.attr, &validate_attr.attr, - &alloc_calls_attr.attr, - &free_calls_attr.attr, #endif #ifdef CONFIG_ZONE_DMA &cache_dma_attr.attr, @@ -5814,6 +5591,283 @@ static int __init slab_sysfs_init(void) __initcall(slab_sysfs_init); #endif /* CONFIG_SYSFS */ +#if defined(CONFIG_DEBUG_FS) && defined(CONFIG_SLUB_DEBUG) +/* + * Generate lists of code addresses where slabcache objects are allocated + * and freed. + */ + +struct location { + unsigned long count; + unsigned long addr; + long long sum_time; + long min_time; + long max_time; + long min_pid; + long max_pid; + DECLARE_BITMAP(cpus, NR_CPUS); + nodemask_t nodes; +}; + +struct loc_track { + unsigned long max; + unsigned long count; + struct location *loc; +}; + +static struct dentry *slab_debugfs_root; + +static struct dentry *slab_debugfs_cache; + +static void free_loc_track(struct loc_track *t) +{ + if (t->max) + free_pages((unsigned long)t->loc, + get_order(sizeof(struct location) * t->max)); +} + +static int alloc_loc_track(struct loc_track *t, unsigned long max, gfp_t flags) +{ + struct location *l; + int order; + + order = get_order(sizeof(struct location) * max); + + l = (void *)__get_free_pages(flags, order); + if (!l) + return 0; + + if (t->count) { + memcpy(l, t->loc, sizeof(struct location) * t->count); + free_loc_track(t); + } + t->max = max; + t->loc = l; + return 1; +} + +static int add_location(struct loc_track *t, struct kmem_cache *s, + const struct track *track) +{ + long start, end, pos; + struct location *l; + unsigned long caddr; + unsigned long age = jiffies - track->when; + + start = -1; + end = t->count; + + for ( ; ; ) { + pos = start + (end - start + 1) / 2; + + /* + * There is nothing at "end". If we end up there + * we need to add something to before end. + */ + if (pos == end) + break; + + caddr = t->loc[pos].addr; + if (track->addr == caddr) { + + l = &t->loc[pos]; + l->count++; + if (track->when) { + l->sum_time += age; + if (age < l->min_time) + l->min_time = age; + if (age > l->max_time) + l->max_time = age; + + if (track->pid < l->min_pid) + l->min_pid = track->pid; + if (track->pid > l->max_pid) + l->max_pid = track->pid; + + cpumask_set_cpu(track->cpu, + to_cpumask(l->cpus)); + } + node_set(page_to_nid(virt_to_page(track)), l->nodes); + return 1; + } + + if (track->addr < caddr) + end = pos; + else + start = pos; + } + + /* + * Not found. Insert new tracking element. + */ + if (t->count >= t->max && !alloc_loc_track(t, 2 * t->max, GFP_ATOMIC)) + return 0; + + l = t->loc + pos; + if (pos < t->count) + memmove(l + 1, l, + (t->count - pos) * sizeof(struct location)); + t->count++; + l->count = 1; + l->addr = track->addr; + l->sum_time = age; + l->min_time = age; + l->max_time = age; + l->min_pid = track->pid; + l->max_pid = track->pid; + cpumask_clear(to_cpumask(l->cpus)); + cpumask_set_cpu(track->cpu, to_cpumask(l->cpus)); + nodes_clear(l->nodes); + node_set(page_to_nid(virt_to_page(track)), l->nodes); + return 1; +} + +static void process_slab(struct loc_track *t, struct kmem_cache *s, + struct page *page, enum track_item alloc) +{ + void *addr = page_address(page); + void *p; + unsigned long *map; + + map = get_map(s, page); + for_each_object(p, s, addr, page->objects) + if (!test_bit(__obj_to_index(s, addr, p), map)) + add_location(t, s, get_track(s, p, alloc)); + put_map(map); +} + +static int list_locations(struct seq_file *seq, struct kmem_cache *s, + enum track_item alloc) +{ + unsigned long i; + struct loc_track t = { 0, 0, NULL }; + int node; + struct kmem_cache_node *n; + + if (!alloc_loc_track(&t, PAGE_SIZE / sizeof(struct location), + GFP_KERNEL)) { + seq_puts(seq, "Out of memory\n"); + return -ENOMEM; + } + /* Push back cpu slabs */ + flush_all(s); + + for_each_kmem_cache_node(s, node, n) { + unsigned long flags; + struct page *page; + + if (!atomic_long_read(&n->nr_slabs)) + continue; + + spin_lock_irqsave(&n->list_lock, flags); + list_for_each_entry(page, &n->partial, slab_list) + process_slab(&t, s, page, alloc); + list_for_each_entry(page, &n->full, slab_list) + process_slab(&t, s, page, alloc); + spin_unlock_irqrestore(&n->list_lock, flags); + } + + for (i = 0; i < t.count; i++) { + struct location *l = &t.loc[i]; + + seq_printf(seq, "%7ld ", l->count); + + if (l->addr) + seq_printf(seq, "%pS", (void *)l->addr); + else + seq_puts(seq, ""); + + if (l->sum_time != l->min_time) { + seq_printf(seq, " age=%ld/%ld/%ld", + l->min_time, + (long)div_u64(l->sum_time, l->count), + l->max_time); + } else + seq_printf(seq, " age=%ld", + l->min_time); + + if (l->min_pid != l->max_pid) + seq_printf(seq, " pid=%ld-%ld", + l->min_pid, l->max_pid); + else + seq_printf(seq, " pid=%ld", + l->min_pid); + + if (num_online_cpus() > 1 && + !cpumask_empty(to_cpumask(l->cpus))) + seq_printf(seq, " cpus=%*pbl", + cpumask_pr_args(to_cpumask(l->cpus))); + + if (nr_online_nodes > 1 && !nodes_empty(l->nodes)) + seq_printf(seq, " nodes=%*pbl", + nodemask_pr_args(&l->nodes)); + + seq_puts(seq, "\n"); + } + + free_loc_track(&t); + if (!t.count) + seq_puts(seq, "No data\n"); + return 0; +} + +static int slab_debug_trace(struct seq_file *seq, void *ignored) +{ + struct kmem_cache *s = seq->private; + + if (!(s->flags & SLAB_STORE_USER)) + return 0; + + if (strcmp(seq->file->f_path.dentry->d_name.name, "alloc_trace") == 0) + return list_locations(seq, s, TRACK_ALLOC); + else + return list_locations(seq, s, TRACK_FREE); + + return 0; +} + +static int slab_debug_trace_open(struct inode *inode, struct file *filp) +{ + return single_open(filp, slab_debug_trace, + file_inode(filp)->i_private); +} + +static const struct file_operations slab_debug_fops = { + .open = slab_debug_trace_open, + .read = seq_read, + .llseek = seq_lseek, + .release = single_release, +}; + +static void debugfs_slab_add(struct kmem_cache *s) +{ + if (unlikely(!slab_debugfs_root)) + return; + + slab_debugfs_cache = debugfs_create_dir(s->name, slab_debugfs_root); + if (!IS_ERR(slab_debugfs_cache)) { + debugfs_create_file("alloc_trace", 0400, + slab_debugfs_cache, s, &slab_debug_fops); + + debugfs_create_file("free_trace", 0400, + slab_debugfs_cache, s, &slab_debug_fops); + } +} + +static void __init slab_debugfs_init(void) +{ + struct kmem_cache *s; + + slab_debugfs_root = debugfs_create_dir("slab", NULL); + if (!IS_ERR(slab_debugfs_root)) + list_for_each_entry(s, &slab_caches, list) + debugfs_slab_add(s); + else + pr_err("Cannot create slab debugfs.\n"); + +} +__initcall(slab_debugfs_init); +#endif /* * The /proc/slabinfo ABI */