Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755444Ab0KSP6c (ORCPT ); Fri, 19 Nov 2010 10:58:32 -0500 Received: from mailout4.w1.samsung.com ([210.118.77.14]:31934 "EHLO mailout4.w1.samsung.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755370Ab0KSP63 (ORCPT ); Fri, 19 Nov 2010 10:58:29 -0500 MIME-version: 1.0 Content-transfer-encoding: 7BIT Content-type: TEXT/PLAIN Date: Fri, 19 Nov 2010 16:58:03 +0100 From: Michal Nazarewicz Subject: [RFCv6 05/13] mm: cma: debugfs support added In-reply-to: To: mina86@mina86.com Cc: Andrew Morton , Ankita Garg , Bryan Huntsman , Daniel Walker , FUJITA Tomonori , Hans Verkuil , Johan Mossberg , Jonathan Corbet , KAMEZAWA Hiroyuki , Konrad Rzeszutek Wilk , Marcus LORENTZON , Marek Szyprowski , Mark Brown , Mel Gorman , Pawel Osciak , Russell King , Vaidyanathan Srinivasan , Zach Pfeffer , dipankar@in.ibm.com, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, linux-media@vger.kernel.org, linux-mm@kvack.org Message-id: <5b4b5dc196968bb3c4c28e3f91b0b9feab6a1c37.1290172312.git.m.nazarewicz@samsung.com> X-Mailer: git-send-email 1.7.2.3 References: Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 15394 Lines: 670 The debugfs development interface lets one change the map attribute at run time as well as observe what regions have been reserved. Signed-off-by: Michal Nazarewicz Signed-off-by: Kyungmin Park --- Documentation/contiguous-memory.txt | 4 + include/linux/cma.h | 11 + mm/Kconfig | 25 ++- mm/cma.c | 501 ++++++++++++++++++++++++++++++++++- 4 files changed, 537 insertions(+), 4 deletions(-) diff --git a/Documentation/contiguous-memory.txt b/Documentation/contiguous-memory.txt index f1715ba..ec09d8e 100644 --- a/Documentation/contiguous-memory.txt +++ b/Documentation/contiguous-memory.txt @@ -258,6 +258,10 @@ iff it matched in previous pattern. If the second part is omitted it will mach any type of memory requested by device. + If debugfs support is enabled, this attribute is accessible via + debugfs and can be changed at run-time by writing to + contiguous/map. + Some examples (whitespace added for better readability): cma_map = foo/quaz = r1; diff --git a/include/linux/cma.h b/include/linux/cma.h index a6031a7..8437104 100644 --- a/include/linux/cma.h +++ b/include/linux/cma.h @@ -24,6 +24,7 @@ struct device; struct cma_info; +struct dentry; /** * struct cma - an allocated contiguous chunk of memory. @@ -276,6 +277,11 @@ struct cma_region { unsigned users; struct list_head list; +#if defined CONFIG_CMA_DEBUGFS + const char *to_alloc_link, *from_alloc_link; + struct dentry *dir, *to_alloc, *from_alloc; +#endif + unsigned used:1; unsigned registered:1; unsigned reserved:1; @@ -382,6 +388,11 @@ struct cma_allocator { void (*unpin)(struct cma *chunk); struct list_head list; + +#if defined CONFIG_CMA_DEBUGFS + const char *dir_name; + struct dentry *regs_dir; +#endif }; /** diff --git a/mm/Kconfig b/mm/Kconfig index c7eb1bc..a5480ea 100644 --- a/mm/Kconfig +++ b/mm/Kconfig @@ -351,16 +351,35 @@ config CMA For more information see . If unsure, say "n". -config CMA_DEBUG - bool "CMA debug messages (DEVELOPEMENT)" +config CMA_DEVELOPEMENT + bool "Include CMA developement features" depends on CMA help + This lets you enable some developement features of the CMA + framework. It does not add any code to the kernel. + + Those options are mostly usable during development and testing. + If unsure, say "n". + +config CMA_DEBUG + bool "CMA debug messages" + depends on CMA_DEVELOPEMENT + help Turns on debug messages in CMA. This produces KERN_DEBUG messages for every CMA call as well as various messages while processing calls such as cma_alloc(). This option does not affect warning and error messages. - This is mostly used during development. If unsure, say "n". +config CMA_DEBUGFS + bool "CMA debugfs interface support" + depends on CMA_DEVELOPEMENT && DEBUG_FS + help + Enable support for debugfs interface. It is available under the + "contiguous" directory in the debugfs root directory. Each + region and allocator is represented there. + + For more information consult + . config CMA_GENERIC_ALLOCATOR bool "CMA generic allocator" diff --git a/mm/cma.c b/mm/cma.c index 17276b3..dfdeeb7 100644 --- a/mm/cma.c +++ b/mm/cma.c @@ -34,11 +34,16 @@ #include /* kmalloc() */ #include /* str*() */ #include /* gen_pool_*() */ +#include /* debugfs stuff */ +#include /* copy_{to,from}_user */ #include -/* Protects cma_regions, cma_allocators, cma_map and cma_map_length. */ +/* + * Protects cma_regions, cma_allocators, cma_map, cma_map_length, + * cma_dfs_regions and cma_dfs_allocators. + */ static DEFINE_MUTEX(cma_mutex); @@ -139,7 +144,13 @@ int __init __must_check cma_early_region_register(struct cma_region *reg) /************************* Regions & Allocators *************************/ +static void __cma_dfs_region_add(struct cma_region *reg); +static void __cma_dfs_region_alloc_update(struct cma_region *reg); +static void __cma_dfs_allocator_add(struct cma_allocator *alloc); + static int __cma_region_attach_alloc(struct cma_region *reg); +static void __maybe_unused __cma_region_detach_alloc(struct cma_region *reg); + /* List of all regions. Named regions are kept before unnamed. */ static LIST_HEAD(cma_regions); @@ -222,6 +233,8 @@ int __must_check cma_region_register(struct cma_region *reg) else list_add_tail(®->list, &cma_regions); + __cma_dfs_region_add(reg); + done: mutex_unlock(&cma_mutex); @@ -298,6 +311,8 @@ int cma_allocator_register(struct cma_allocator *alloc) __cma_region_attach_alloc(reg); } + __cma_dfs_allocator_add(alloc); + mutex_unlock(&cma_mutex); pr_debug("%s: allocator registered\n", alloc->name ?: "(unnamed)"); @@ -481,6 +496,476 @@ static int __init cma_init(void) subsys_initcall(cma_init); +/************************* Debugfs *************************/ + +#if defined CONFIG_CMA_DEBUGFS + +static struct dentry *cma_dfs_regions, *cma_dfs_allocators; + +struct cma_dfs_file { + const char *name; + const struct file_operations *ops; +}; + +static struct dentry * +cma_dfs_create_file(const char *name, struct dentry *parent, + void *priv, const struct file_operations *ops) +{ + struct dentry *d; + d = debugfs_create_file(name, ops->write ? 0644 : 0444, + parent, priv, ops); + if (IS_ERR_OR_NULL(d)) { + pr_err("debugfs: %s: %s: unable to create\n", + parent->d_iname, name); + return NULL; + } + + return d; +} + +static void cma_dfs_create_files(const struct cma_dfs_file *files, + struct dentry *parent, void *priv) +{ + while (files->name + && cma_dfs_create_file(files->name, parent, priv, files->ops)) + ++files; +} + +static struct dentry * +cma_dfs_create_dir(const char *name, struct dentry *parent) +{ + struct dentry *d = debugfs_create_dir(name, parent); + + if (IS_ERR_OR_NULL(d)) { + pr_err("debugfs: %s: %s: unable to create\n", + parent ? (const char *)parent->d_iname : "", name); + return NULL; + } + + return d; +} + +static struct dentry * +cma_dfs_create_lnk(const char *name, struct dentry *parent, const char *target) +{ + struct dentry *d = debugfs_create_symlink(name, parent, target); + + if (IS_ERR_OR_NULL(d)) { + pr_err("debugfs: %s: %s: unable to create\n", + parent->d_iname, name); + return NULL; + } + + return d; +} + +static int cma_dfs_open(struct inode *inode, struct file *file) +{ + file->private_data = inode->i_private; + return 0; +} + +static ssize_t cma_dfs_map_read(struct file *file, char __user *buf, + size_t size, loff_t *offp) +{ + ssize_t len; + + if (!cma_map_length || *offp) + return 0; + + mutex_lock(&cma_mutex); + + /* may have changed */ + len = cma_map_length; + if (!len) + goto done; + + len = min_t(size_t, size, len); + if (copy_to_user(buf, cma_map, len)) + len = -EFAULT; + else if ((size_t)len < size && put_user('\n', buf + len++)) + len = -EFAULT; + +done: + mutex_unlock(&cma_mutex); + + if (len > 0) + *offp = len; + + return len; +} + +static ssize_t cma_dfs_map_write(struct file *file, const char __user *buf, + size_t size, loff_t *offp) +{ + char *val, *v; + ssize_t len; + + if (size >= PAGE_SIZE || *offp) + return -ENOSPC; + + val = kmalloc(size + 1, GFP_KERNEL); + if (!val) + return -ENOMEM; + + if (copy_from_user(val, buf, size)) { + len = -EFAULT; + goto done; + } + val[size] = '\0'; + + len = cma_map_validate(val); + if (len < 0) + goto done; + val[len] = '\0'; + + mutex_lock(&cma_mutex); + v = (char *)cma_map; + cma_map = val; + val = v; + cma_map_length = len; + mutex_unlock(&cma_mutex); + +done: + kfree(val); + + if (len > 0) + *offp = len; + + return len; +} + +static int __init cma_dfs_init(void) +{ + static const struct file_operations map_ops = { + .read = cma_dfs_map_read, + .write = cma_dfs_map_write, + }; + + struct dentry *root, *a, *r; + + root = cma_dfs_create_dir("contiguous", NULL); + if (!root) + return 0; + + if (!cma_dfs_create_file("map", root, NULL, &map_ops)) + goto error; + + a = cma_dfs_create_dir("allocators", root); + if (!a) + goto error; + + r = cma_dfs_create_dir("regions", root); + if (!r) + goto error; + + mutex_lock(&cma_mutex); + { + struct cma_allocator *alloc; + cma_dfs_allocators = a; + cma_foreach_allocator(alloc) + __cma_dfs_allocator_add(alloc); + } + + { + struct cma_region *reg; + cma_dfs_regions = r; + cma_foreach_region(reg) + __cma_dfs_region_add(reg); + } + mutex_unlock(&cma_mutex); + + return 0; + +error: + debugfs_remove_recursive(root); + return 0; +} +device_initcall(cma_dfs_init); + +static ssize_t cma_dfs_region_name_read(struct file *file, char __user *buf, + size_t size, loff_t *offp) +{ + struct cma_region *reg = file->private_data; + size_t len; + + if (!reg->name || *offp) + return 0; + + len = min(strlen(reg->name), size); + if (copy_to_user(buf, reg->name, len)) + return -EFAULT; + if (len < size && put_user('\n', buf + len++)) + return -EFAULT; + + *offp = len; + return len; +} + +static ssize_t cma_dfs_region_info_read(struct file *file, char __user *buf, + size_t size, loff_t *offp) +{ + struct cma_region *reg = file->private_data; + char str[min((size_t)63, size) + 1]; + int len; + + if (*offp) + return 0; + + len = snprintf(str, sizeof str, "%p %p %p\n", + (void *)reg->start, (void *)reg->size, + (void *)reg->free_space); + + if (copy_to_user(buf, str, len)) + return -EFAULT; + + *offp = len; + return len; +} + +static ssize_t cma_dfs_region_alloc_read(struct file *file, char __user *buf, + size_t size, loff_t *offp) +{ + struct cma_region *reg = file->private_data; + char str[min((size_t)63, size) + 1]; + const char *fmt; + const void *arg; + int len = 0; + + if (*offp) + return 0; + + mutex_lock(&cma_mutex); + + if (reg->alloc) { + if (reg->alloc->name) { + fmt = "%s\n"; + arg = reg->alloc->name; + } else { + fmt = "0x%p\n"; + arg = (void *)reg->alloc; + } + } else if (reg->alloc_name) { + fmt = "[%s]\n"; + arg = reg->alloc_name; + } else { + goto done; + } + + len = snprintf(str, sizeof str, fmt, arg); + +done: + mutex_unlock(&cma_mutex); + + if (len) { + if (copy_to_user(buf, str, len)) + return -EFAULT; + *offp = len; + } + return len; +} + +static ssize_t +cma_dfs_region_alloc_write(struct file *file, const char __user *buf, + size_t size, loff_t *offp) +{ + struct cma_region *reg = file->private_data; + ssize_t ret; + char *s, *t; + + if (size > 64 || *offp) + return -ENOSPC; + + if (reg->alloc && reg->users) + return -EBUSY; + + s = kmalloc(size + 1, GFP_KERNEL); + if (!s) + return -ENOMEM; + + if (copy_from_user(s, buf, size)) { + ret = -EFAULT; + goto done_free; + } + + s[size] = '\0'; + t = strchr(s, '\n'); + if (t == s) { + kfree(s); + s = NULL; + } + if (t) + *t = '\0'; + + mutex_lock(&cma_mutex); + + /* things may have changed while we were acquiring lock */ + if (reg->alloc && reg->users) { + ret = -EBUSY; + } else { + if (reg->alloc) + __cma_region_detach_alloc(reg); + + t = s; + s = reg->free_alloc_name ? (char *)reg->alloc_name : NULL; + + reg->alloc_name = t; + reg->free_alloc_name = 1; + + ret = size; + } + + mutex_unlock(&cma_mutex); + +done_free: + kfree(s); + + if (ret > 0) + *offp = ret; + return ret; +} + +static const struct cma_dfs_file __cma_dfs_region_files[] = { + { + "name", &(const struct file_operations){ + .open = cma_dfs_open, + .read = cma_dfs_region_name_read, + }, + }, + { + "info", &(const struct file_operations){ + .open = cma_dfs_open, + .read = cma_dfs_region_info_read, + }, + }, + { + "alloc", &(const struct file_operations){ + .open = cma_dfs_open, + .read = cma_dfs_region_alloc_read, + .write = cma_dfs_region_alloc_write, + }, + }, + { } +}; + +static void __cma_dfs_region_add(struct cma_region *reg) +{ + struct dentry *d; + + if (!cma_dfs_regions || reg->dir) + return; + + /* Region's directory */ + reg->from_alloc_link = kasprintf(GFP_KERNEL, "../../regions/0x%p", + (void *)reg->start); + if (!reg->from_alloc_link) + return; + + d = cma_dfs_create_dir(reg->from_alloc_link + 14, cma_dfs_regions); + if (!d) { + kfree(reg->from_alloc_link); + return; + } + + if (reg->name) + cma_dfs_create_lnk(reg->name, cma_dfs_regions, + reg->from_alloc_link + 14); + + reg->dir = d; + + /* Files */ + cma_dfs_create_files(__cma_dfs_region_files, d, reg); + + /* Link to allocator */ + __cma_dfs_region_alloc_update(reg); +} + +static void __cma_dfs_region_alloc_update(struct cma_region *reg) +{ + if (!cma_dfs_regions || !cma_dfs_allocators || !reg->dir) + return; + + /* Remove stall links */ + if (reg->to_alloc) { + debugfs_remove(reg->to_alloc); + reg->to_alloc = NULL; + } + + if (reg->from_alloc) { + debugfs_remove(reg->from_alloc); + reg->from_alloc = NULL; + } + + if (reg->to_alloc_link) { + kfree(reg->to_alloc_link); + reg->to_alloc_link = NULL; + } + + if (!reg->alloc) + return; + + /* Create new links */ + if (reg->alloc->regs_dir) + reg->from_alloc = + cma_dfs_create_lnk(reg->from_alloc_link + 14, + reg->alloc->regs_dir, + reg->from_alloc_link); + + if (!reg->alloc->dir_name) + return; + + reg->to_alloc_link = kasprintf(GFP_KERNEL, "../allocators/%s", + reg->alloc->dir_name); + if (reg->to_alloc_link && + !cma_dfs_create_lnk("allocator", reg->dir, reg->to_alloc_link)) { + kfree(reg->to_alloc_link); + reg->to_alloc_link = NULL; + } +} + +static inline void __cma_dfs_allocator_add(struct cma_allocator *alloc) +{ + struct dentry *d; + + if (!cma_dfs_allocators || alloc->dir_name) + return; + + alloc->dir_name = alloc->name ?: + kasprintf(GFP_KERNEL, "0x%p", (void *)alloc); + if (!alloc->dir_name) + return; + + d = cma_dfs_create_dir(alloc->dir_name, cma_dfs_allocators); + if (!d) { + if (!alloc->name) + kfree(alloc->dir_name); + alloc->dir_name = NULL; + return; + } + + alloc->regs_dir = cma_dfs_create_dir("regions", d); +} + +#else + +static inline void __cma_dfs_region_add(struct cma_region *reg) +{ + /* nop */ +} + +static inline void __cma_dfs_allocator_add(struct cma_allocator *alloc) +{ + /* nop */ +} + +static inline void __cma_dfs_region_alloc_update(struct cma_region *reg) +{ + /* nop */ +} + +#endif + + /************************* The Device API *************************/ static const char *__must_check @@ -731,10 +1216,24 @@ static int __cma_region_attach_alloc(struct cma_region *reg) reg->alloc = alloc; pr_debug("init: %s: %s: initialised allocator\n", reg->name ?: "(private)", alloc->name ?: "(unnamed)"); + __cma_dfs_region_alloc_update(reg); } return ret; } +static void __cma_region_detach_alloc(struct cma_region *reg) +{ + if (!reg->alloc) + return; + + if (reg->alloc->cleanup) + reg->alloc->cleanup(reg); + + reg->alloc = NULL; + reg->used = 1; + __cma_dfs_region_alloc_update(reg); +} + /* * s ::= rules -- 1.7.2.3 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/