diff options
| -rw-r--r-- | Documentation/admin-guide/dynamic-debug-howto.rst | 246 | ||||
| -rw-r--r-- | Documentation/driver-api/driver-model/devres.rst | 1 | ||||
| -rw-r--r-- | Documentation/process/code-of-conduct-interpretation.rst | 2 | ||||
| -rw-r--r-- | Documentation/process/stable-kernel-rules.rst | 6 | ||||
| -rw-r--r-- | MAINTAINERS | 2 | ||||
| -rw-r--r-- | drivers/base/base.h | 2 | ||||
| -rw-r--r-- | drivers/base/class.c | 2 | ||||
| -rw-r--r-- | drivers/base/core.c | 2 | ||||
| -rw-r--r-- | drivers/base/dd.c | 2 | ||||
| -rw-r--r-- | drivers/base/devres.c | 4 | ||||
| -rw-r--r-- | fs/kernfs/dir.c | 102 | ||||
| -rw-r--r-- | fs/kernfs/file.c | 151 | ||||
| -rw-r--r-- | fs/kernfs/kernfs-internal.h | 1 | ||||
| -rw-r--r-- | include/asm-generic/vmlinux.lds.h | 3 | ||||
| -rw-r--r-- | include/linux/cgroup.h | 1 | ||||
| -rw-r--r-- | include/linux/dynamic_debug.h | 176 | ||||
| -rw-r--r-- | include/linux/io.h | 2 | ||||
| -rw-r--r-- | include/linux/kernfs.h | 3 | ||||
| -rw-r--r-- | kernel/cgroup/cgroup.c | 20 | ||||
| -rw-r--r-- | kernel/module/internal.h | 4 | ||||
| -rw-r--r-- | kernel/module/main.c | 20 | ||||
| -rw-r--r-- | lib/Kconfig.debug | 10 | ||||
| -rw-r--r-- | lib/Makefile | 1 | ||||
| -rw-r--r-- | lib/devres.c | 15 | ||||
| -rw-r--r-- | lib/dynamic_debug.c | 450 | ||||
| -rw-r--r-- | lib/test_dynamic_debug.c | 165 |
26 files changed, 1027 insertions, 366 deletions
diff --git a/Documentation/admin-guide/dynamic-debug-howto.rst b/Documentation/admin-guide/dynamic-debug-howto.rst index a89cfa083155..faa22f77847a 100644 --- a/Documentation/admin-guide/dynamic-debug-howto.rst +++ b/Documentation/admin-guide/dynamic-debug-howto.rst @@ -5,143 +5,115 @@ Dynamic debug Introduction ============ -This document describes how to use the dynamic debug (dyndbg) feature. +Dynamic debug allows you to dynamically enable/disable kernel +debug-print code to obtain additional kernel information. -Dynamic debug is designed to allow you to dynamically enable/disable -kernel code to obtain additional kernel information. Currently, if -``CONFIG_DYNAMIC_DEBUG`` is set, then all ``pr_debug()``/``dev_dbg()`` and -``print_hex_dump_debug()``/``print_hex_dump_bytes()`` calls can be dynamically -enabled per-callsite. +If ``/proc/dynamic_debug/control`` exists, your kernel has dynamic +debug. You'll need root access (sudo su) to use this. -If you do not want to enable dynamic debug globally (i.e. in some embedded -system), you may set ``CONFIG_DYNAMIC_DEBUG_CORE`` as basic support of dynamic -debug and add ``ccflags := -DDYNAMIC_DEBUG_MODULE`` into the Makefile of any -modules which you'd like to dynamically debug later. - -If ``CONFIG_DYNAMIC_DEBUG`` is not set, ``print_hex_dump_debug()`` is just -shortcut for ``print_hex_dump(KERN_DEBUG)``. - -For ``print_hex_dump_debug()``/``print_hex_dump_bytes()``, format string is -its ``prefix_str`` argument, if it is constant string; or ``hexdump`` -in case ``prefix_str`` is built dynamically. +Dynamic debug provides: -Dynamic debug has even more useful features: + * a Catalog of all *prdbgs* in your kernel. + ``cat /proc/dynamic_debug/control`` to see them. - * Simple query language allows turning on and off debugging - statements by matching any combination of 0 or 1 of: + * a Simple query/command language to alter *prdbgs* by selecting on + any combination of 0 or 1 of: - source filename - function name - line number (including ranges of line numbers) - module name - format string - - * Provides a debugfs control file: ``<debugfs>/dynamic_debug/control`` - which can be read to display the complete list of known debug - statements, to help guide you - -Controlling dynamic debug Behaviour -=================================== - -The behaviour of ``pr_debug()``/``dev_dbg()`` are controlled via writing to a -control file in the 'debugfs' filesystem. Thus, you must first mount -the debugfs filesystem, in order to make use of this feature. -Subsequently, we refer to the control file as: -``<debugfs>/dynamic_debug/control``. For example, if you want to enable -printing from source file ``svcsock.c``, line 1603 you simply do:: - - nullarbor:~ # echo 'file svcsock.c line 1603 +p' > - <debugfs>/dynamic_debug/control - -If you make a mistake with the syntax, the write will fail thus:: - - nullarbor:~ # echo 'file svcsock.c wtf 1 +p' > - <debugfs>/dynamic_debug/control - -bash: echo: write error: Invalid argument - -Note, for systems without 'debugfs' enabled, the control file can be -found in ``/proc/dynamic_debug/control``. + - class name (as known/declared by each module) Viewing Dynamic Debug Behaviour =============================== -You can view the currently configured behaviour of all the debug -statements via:: +You can view the currently configured behaviour in the *prdbg* catalog:: - nullarbor:~ # cat <debugfs>/dynamic_debug/control + :#> head -n7 /proc/dynamic_debug/control # filename:lineno [module]function flags format - net/sunrpc/svc_rdma.c:323 [svcxprt_rdma]svc_rdma_cleanup =_ "SVCRDMA Module Removed, deregister RPC RDMA transport\012" - net/sunrpc/svc_rdma.c:341 [svcxprt_rdma]svc_rdma_init =_ "\011max_inline : %d\012" - net/sunrpc/svc_rdma.c:340 [svcxprt_rdma]svc_rdma_init =_ "\011sq_depth : %d\012" - net/sunrpc/svc_rdma.c:338 [svcxprt_rdma]svc_rdma_init =_ "\011max_requests : %d\012" - ... + init/main.c:1179 [main]initcall_blacklist =_ "blacklisting initcall %s\012 + init/main.c:1218 [main]initcall_blacklisted =_ "initcall %s blacklisted\012" + init/main.c:1424 [main]run_init_process =_ " with arguments:\012" + init/main.c:1426 [main]run_init_process =_ " %s\012" + init/main.c:1427 [main]run_init_process =_ " with environment:\012" + init/main.c:1429 [main]run_init_process =_ " %s\012" +The 3rd space-delimited column shows the current flags, preceded by +a ``=`` for easy use with grep/cut. ``=p`` shows enabled callsites. -You can also apply standard Unix text manipulation filters to this -data, e.g.:: +Controlling dynamic debug Behaviour +=================================== - nullarbor:~ # grep -i rdma <debugfs>/dynamic_debug/control | wc -l - 62 +The behaviour of *prdbg* sites are controlled by writing +query/commands to the control file. Example:: - nullarbor:~ # grep -i tcp <debugfs>/dynamic_debug/control | wc -l - 42 + # grease the interface + :#> alias ddcmd='echo $* > /proc/dynamic_debug/control' -The third column shows the currently enabled flags for each debug -statement callsite (see below for definitions of the flags). The -default value, with no flags enabled, is ``=_``. So you can view all -the debug statement callsites with any non-default flags:: + :#> ddcmd '-p; module main func run* +p' + :#> grep =p /proc/dynamic_debug/control + init/main.c:1424 [main]run_init_process =p " with arguments:\012" + init/main.c:1426 [main]run_init_process =p " %s\012" + init/main.c:1427 [main]run_init_process =p " with environment:\012" + init/main.c:1429 [main]run_init_process =p " %s\012" - nullarbor:~ # awk '$3 != "=_"' <debugfs>/dynamic_debug/control - # filename:lineno [module]function flags format - net/sunrpc/svcsock.c:1603 [sunrpc]svc_send p "svc_process: st_sendto returned %d\012" +Error messages go to console/syslog:: + + :#> ddcmd mode foo +p + dyndbg: unknown keyword "mode" + dyndbg: query parse failed + bash: echo: write error: Invalid argument + +If debugfs is also enabled and mounted, ``dynamic_debug/control`` is +also under the mount-dir, typically ``/sys/kernel/debug/``. Command Language Reference ========================== -At the lexical level, a command comprises a sequence of words separated +At the basic lexical level, a command is a sequence of words separated by spaces or tabs. So these are all equivalent:: - nullarbor:~ # echo -n 'file svcsock.c line 1603 +p' > - <debugfs>/dynamic_debug/control - nullarbor:~ # echo -n ' file svcsock.c line 1603 +p ' > - <debugfs>/dynamic_debug/control - nullarbor:~ # echo -n 'file svcsock.c line 1603 +p' > - <debugfs>/dynamic_debug/control + :#> ddcmd file svcsock.c line 1603 +p + :#> ddcmd "file svcsock.c line 1603 +p" + :#> ddcmd ' file svcsock.c line 1603 +p ' Command submissions are bounded by a write() system call. Multiple commands can be written together, separated by ``;`` or ``\n``:: - ~# echo "func pnpacpi_get_resources +p; func pnp_assign_mem +p" \ - > <debugfs>/dynamic_debug/control + :#> ddcmd "func pnpacpi_get_resources +p; func pnp_assign_mem +p" + :#> ddcmd <<"EOC" + func pnpacpi_get_resources +p + func pnp_assign_mem +p + EOC + :#> cat query-batch-file > /proc/dynamic_debug/control -If your query set is big, you can batch them too:: +You can also use wildcards in each query term. The match rule supports +``*`` (matches zero or more characters) and ``?`` (matches exactly one +character). For example, you can match all usb drivers:: - ~# cat query-batch-file > <debugfs>/dynamic_debug/control + :#> ddcmd file "drivers/usb/*" +p # "" to suppress shell expansion -Another way is to use wildcards. The match rule supports ``*`` (matches -zero or more characters) and ``?`` (matches exactly one character). For -example, you can match all usb drivers:: - - ~# echo "file drivers/usb/* +p" > <debugfs>/dynamic_debug/control - -At the syntactical level, a command comprises a sequence of match -specifications, followed by a flags change specification:: +Syntactically, a command is pairs of keyword values, followed by a +flags change or setting:: command ::= match-spec* flags-spec -The match-spec's are used to choose a subset of the known pr_debug() -callsites to which to apply the flags-spec. Think of them as a query -with implicit ANDs between each pair. Note that an empty list of -match-specs will select all debug statement callsites. +The match-spec's select *prdbgs* from the catalog, upon which to apply +the flags-spec, all constraints are ANDed together. An absent keyword +is the same as keyword "*". + -A match specification comprises a keyword, which controls the -attribute of the callsite to be compared, and a value to compare -against. Possible keywords are::: +A match specification is a keyword, which selects the attribute of +the callsite to be compared, and a value to compare against. Possible +keywords are::: match-spec ::= 'func' string | 'file' string | 'module' string | 'format' string | + 'class' string | 'line' line-range line-range ::= lineno | @@ -203,6 +175,16 @@ format format "nfsd: SETATTR" // a neater way to match a format with whitespace format 'nfsd: SETATTR' // yet another way to match a format with whitespace +class + The given class_name is validated against each module, which may + have declared a list of known class_names. If the class_name is + found for a module, callsite & class matching and adjustment + proceeds. Examples:: + + class DRM_UT_KMS # a DRM.debug category + class JUNK # silent non-match + // class TLD_* # NOTICE: no wildcard in class names + line The given line number or range of line numbers is compared against the line number of each ``pr_debug()`` callsite. A single @@ -228,17 +210,16 @@ of the characters:: The flags are:: p enables the pr_debug() callsite. - f Include the function name in the printed message - l Include line number in the printed message - m Include module name in the printed message - t Include thread ID in messages not generated from interrupt context - _ No flags are set. (Or'd with others on input) + _ enables no flags. -For ``print_hex_dump_debug()`` and ``print_hex_dump_bytes()``, only ``p`` flag -have meaning, other flags ignored. + Decorator flags add to the message-prefix, in order: + t Include thread ID, or <intr> + m Include module name + f Include the function name + l Include line number -For display, the flags are preceded by ``=`` -(mnemonic: what the flags are currently equal to). +For ``print_hex_dump_debug()`` and ``print_hex_dump_bytes()``, only +the ``p`` flag has meaning, other flags are ignored. Note the regexp ``^[-+=][flmpt_]+$`` matches a flags specification. To clear all flags at once, use ``=_`` or ``-flmpt``. @@ -313,7 +294,7 @@ For ``CONFIG_DYNAMIC_DEBUG`` kernels, any settings given at boot-time (or enabled by ``-DDEBUG`` flag during compilation) can be disabled later via the debugfs interface if the debug messages are no longer needed:: - echo "module module_name -p" > <debugfs>/dynamic_debug/control + echo "module module_name -p" > /proc/dynamic_debug/control Examples ======== @@ -321,37 +302,31 @@ Examples :: // enable the message at line 1603 of file svcsock.c - nullarbor:~ # echo -n 'file svcsock.c line 1603 +p' > - <debugfs>/dynamic_debug/control + :#> ddcmd 'file svcsock.c line 1603 +p' // enable all the messages in file svcsock.c - nullarbor:~ # echo -n 'file svcsock.c +p' > - <debugfs>/dynamic_debug/control + :#> ddcmd 'file svcsock.c +p' // enable all the messages in the NFS server module - nullarbor:~ # echo -n 'module nfsd +p' > - <debugfs>/dynamic_debug/control + :#> ddcmd 'module nfsd +p' // enable all 12 messages in the function svc_process() - nullarbor:~ # echo -n 'func svc_process +p' > - <debugfs>/dynamic_debug/control + :#> ddcmd 'func svc_process +p' // disable all 12 messages in the function svc_process() - nullarbor:~ # echo -n 'func svc_process -p' > - <debugfs>/dynamic_debug/control + :#> ddcmd 'func svc_process -p' // enable messages for NFS calls READ, READLINK, READDIR and READDIR+. - nullarbor:~ # echo -n 'format "nfsd: READ" +p' > - <debugfs>/dynamic_debug/control + :#> ddcmd 'format "nfsd: READ" +p' // enable messages in files of which the paths include string "usb" - nullarbor:~ # echo -n 'file *usb* +p' > <debugfs>/dynamic_debug/control + :#> ddcmd 'file *usb* +p' > /proc/dynamic_debug/control // enable all messages - nullarbor:~ # echo -n '+p' > <debugfs>/dynamic_debug/control + :#> ddcmd '+p' > /proc/dynamic_debug/control // add module, function to all enabled messages - nullarbor:~ # echo -n '+mf' > <debugfs>/dynamic_debug/control + :#> ddcmd '+mf' > /proc/dynamic_debug/control // boot-args example, with newlines and comments for readability Kernel command line: ... @@ -364,3 +339,38 @@ Examples dyndbg="file init/* +p #cmt ; func parse_one +p" // enable pr_debugs in 2 functions in a module loaded later pc87360.dyndbg="func pc87360_init_device +p; func pc87360_find +p" + +Kernel Configuration +==================== + +Dynamic Debug is enabled via kernel config items:: + + CONFIG_DYNAMIC_DEBUG=y # build catalog, enables CORE + CONFIG_DYNAMIC_DEBUG_CORE=y # enable mechanics only, skip catalog + +If you do not want to enable dynamic debug globally (i.e. in some embedded +system), you may set ``CONFIG_DYNAMIC_DEBUG_CORE`` as basic support of dynamic +debug and add ``ccflags := -DDYNAMIC_DEBUG_MODULE`` into the Makefile of any +modules which you'd like to dynamically debug later. + + +Kernel *prdbg* API +================== + +The following functions are cataloged and controllable when dynamic +debug is enabled:: + + pr_debug() + dev_dbg() + print_hex_dump_debug() + print_hex_dump_bytes() + +Otherwise, they are off by default; ``ccflags += -DDEBUG`` or +``#define DEBUG`` in a source file will enable them appropriately. + +If ``CONFIG_DYNAMIC_DEBUG`` is not set, ``print_hex_dump_debug()`` is +just a shortcut for ``print_hex_dump(KERN_DEBUG)``. + +For ``print_hex_dump_debug()``/``print_hex_dump_bytes()``, format string is +its ``prefix_str`` argument, if it is constant string; or ``hexdump`` +in case ``prefix_str`` is built dynamically. diff --git a/Documentation/driver-api/driver-model/devres.rst b/Documentation/driver-api/driver-model/devres.rst index 55272942e721..2af6c9c09e59 100644 --- a/Documentation/driver-api/driver-model/devres.rst +++ b/Documentation/driver-api/driver-model/devres.rst @@ -310,7 +310,6 @@ IOMAP devm_ioremap() devm_ioremap_uc() devm_ioremap_wc() - devm_ioremap_np() devm_ioremap_resource() : checks resource, requests memory region, ioremaps devm_ioremap_resource_wc() devm_platform_ioremap_resource() : calls devm_ioremap_resource() for platform device diff --git a/Documentation/process/code-of-conduct-interpretation.rst b/Documentation/process/code-of-conduct-interpretation.rst index e899f14a4ba2..4f8a06b00f60 100644 --- a/Documentation/process/code-of-conduct-interpretation.rst +++ b/Documentation/process/code-of-conduct-interpretation.rst @@ -51,7 +51,7 @@ the Technical Advisory Board (TAB) or other maintainers if you're uncertain how to handle situations that come up. It will not be considered a violation report unless you want it to be. If you are uncertain about approaching the TAB or any other maintainers, please -reach out to our conflict mediator, Mishi Choudhary <mishi@linux.com>. +reach out to our conflict mediator, Joanna Lee <joanna.lee@gesmer.com>. In the end, "be kind to each other" is really what the end goal is for everybody. We know everyone is human and we all fail at times, but the diff --git a/Documentation/process/stable-kernel-rules.rst b/Documentation/process/stable-kernel-rules.rst index c61865e91f52..2fd8aa593a28 100644 --- a/Documentation/process/stable-kernel-rules.rst +++ b/Documentation/process/stable-kernel-rules.rst @@ -97,6 +97,12 @@ text, like this: commit <sha1> upstream. +or alternatively: + +.. code-block:: none + + [ Upstream commit <sha1> ] + Additionally, some patches submitted via :ref:`option_1` may have additional patch prerequisites which can be cherry-picked. This can be specified in the following format in the sign-off area: diff --git a/MAINTAINERS b/MAINTAINERS index 936490dcc97b..5eae4667bc5f 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -7207,6 +7207,8 @@ M: Jason Baron <jbaron@akamai.com> S: Maintained F: include/linux/dynamic_debug.h F: lib/dynamic_debug.c +M: Jim Cromie <jim.cromie@gmail.com> +F: lib/test_dynamic_debug.c DYNAMIC INTERRUPT MODERATION M: Tal Gilboa <talgi@nvidia.com> diff --git a/drivers/base/base.h b/drivers/base/base.h index b3a43a164dcd..b902d1ecc247 100644 --- a/drivers/base/base.h +++ b/drivers/base/base.h @@ -154,8 +154,6 @@ extern void driver_remove_groups(struct device_driver *drv, const struct attribute_group **groups); void device_driver_detach(struct device *dev); -extern char *make_class_name(const char *name, struct kobject *kobj); - extern int devres_release_all(struct device *dev); extern void device_block_probing(void); extern void device_unblock_probing(void); diff --git a/drivers/base/class.c b/drivers/base/class.c index 8feb85e186e3..64f7b9a0970f 100644 --- a/drivers/base/class.c +++ b/drivers/base/class.c @@ -260,7 +260,7 @@ EXPORT_SYMBOL_GPL(__class_create); */ void class_destroy(struct class *cls) { - if ((cls == NULL) || (IS_ERR(cls))) + if (IS_ERR_OR_NULL(cls)) return; class_unregister(cls); diff --git a/drivers/base/core.c b/drivers/base/core.c index 753e7cca0f40..fd0410329046 100644 --- a/drivers/base/core.c +++ b/drivers/base/core.c @@ -2509,7 +2509,7 @@ static ssize_t uevent_store(struct device *dev, struct device_attribute *attr, rc = kobject_synth_uevent(&dev->kobj, buf, count); if (rc) { - dev_err(dev, "uevent: failed to send synthetic uevent\n"); + dev_err(dev, "uevent: failed to send synthetic uevent: %d\n", rc); return rc; } diff --git a/drivers/base/dd.c b/drivers/base/dd.c index ec69b43f926a..3dda62503102 100644 --- a/drivers/base/dd.c +++ b/drivers/base/dd.c @@ -836,7 +836,7 @@ static int __init save_async_options(char *buf) if (strlen(buf) >= ASYNC_DRV_NAMES_MAX_LEN) pr_warn("Too long list of driver names for 'driver_async_probe'!\n"); - strlcpy(async_probe_drv_names, buf, ASYNC_DRV_NAMES_MAX_LEN); + strscpy(async_probe_drv_names, buf, ASYNC_DRV_NAMES_MAX_LEN); async_probe_default = parse_option_str(async_probe_drv_names, "*"); return 1; diff --git a/drivers/base/devres.c b/drivers/base/devres.c index 864d0b3f566e..4ab2b50ee38f 100644 --- a/drivers/base/devres.c +++ b/drivers/base/devres.c @@ -117,7 +117,9 @@ static __always_inline struct devres * alloc_dr(dr_release_t release, if (unlikely(!dr)) return NULL; - memset(dr, 0, offsetof(struct devres, data)); + /* No need to clear memory twice */ + if (!(gfp & __GFP_ZERO)) + memset(dr, 0, offsetof(struct devres, data)); INIT_LIST_HEAD(&dr->node.entry); dr->node.release = release; diff --git a/fs/kernfs/dir.c b/fs/kernfs/dir.c index 1cc88ba6de90..7fb5a72cc96d 100644 --- a/fs/kernfs/dir.c +++ b/fs/kernfs/dir.c @@ -472,6 +472,16 @@ static void kernfs_drain(struct kernfs_node *kn) lockdep_assert_held_write(&root->kernfs_rwsem); WARN_ON_ONCE(kernfs_active(kn)); + /* + * Skip draining if already fully drained. This avoids draining and its + * lockdep annotations for nodes which have never been activated + * allowing embedding kernfs_remove() in create error paths without + * worrying about draining. + */ + if (atomic_read(&kn->active) == KN_DEACTIVATED_BIAS && + !kernfs_should_drain_open_files(kn)) + return; + up_write(&root->kernfs_rwsem); if (kernfs_lockdep(kn)) { @@ -480,7 +490,6 @@ static void kernfs_drain(struct kernfs_node *kn) lock_contended(&kn->dep_map, _RET_IP_); } - /* but everyone should wait for draining */ wait_event(root->deactivate_waitq, atomic_read(&kn->active) == KN_DEACTIVATED_BIAS); @@ -489,7 +498,8 @@ static void kernfs_drain(struct kernfs_node *kn) rwsem_release(&kn->dep_map, _RET_IP_); } - kernfs_drain_open_files(kn); + if (kernfs_should_drain_open_files(kn)) + kernfs_drain_open_files(kn); down_write(&root->kernfs_rwsem); } @@ -695,13 +705,7 @@ struct kernfs_node *kernfs_find_and_get_node_by_id(struct kernfs_root *root, goto err_unlock; } - /* - * ACTIVATED is protected with kernfs_mutex but it was clear when - * @kn was added to idr and we just wanna see it set. No need to - * grab kernfs_mutex. - */ - if (unlikely(!(kn->flags & KERNFS_ACTIVATED) || - !atomic_inc_not_zero(&kn->count))) + if (unlikely(!kernfs_active(kn) || !atomic_inc_not_zero(&kn->count))) goto err_unlock; spin_unlock(&kernfs_idr_lock); @@ -743,10 +747,7 @@ int kernfs_add_one(struct kernfs_node *kn) goto out_unlock; ret = -ENOENT; - if (parent->flags & KERNFS_EMPTY_DIR) - goto out_unlock; - - if ((parent->flags & KERNFS_ACTIVATED) && !kernfs_active(parent)) + if (parent->flags & (KERNFS_REMOVING | KERNFS_EMPTY_DIR)) goto out_unlock; kn->hash = kernfs_name_hash(kn->name, kn->ns); @@ -1304,6 +1305,21 @@ static struct kernfs_node *kernfs_next_descendant_post(struct kernfs_node *pos, return pos->parent; } +static void kernfs_activate_one(struct kernfs_node *kn) +{ + lockdep_assert_held_write(&kernfs_root(kn)->kernfs_rwsem); + + kn->flags |= KERNFS_ACTIVATED; + + if (kernfs_active(kn) || (kn->flags & (KERNFS_HIDDEN | KERNFS_REMOVING))) + return; + + WARN_ON_ONCE(kn->parent && RB_EMPTY_NODE(&kn->rb)); + WARN_ON_ONCE(atomic_read(&kn->active) != KN_DEACTIVATED_BIAS); + + atomic_sub(KN_DEACTIVATED_BIAS, &kn->active); +} + /** * kernfs_activate - activate a node which started deactivated * @kn: kernfs_node whose subtree is to be activated @@ -1325,15 +1341,42 @@ void kernfs_activate(struct kernfs_node *kn) down_write(&root->kernfs_rwsem); pos = NULL; - while ((pos = kernfs_next_descendant_post(pos, kn))) { - if (pos->flags & KERNFS_ACTIVATED) - continue; + while ((pos = kernfs_next_descendant_post(pos, kn))) + kernfs_activate_one(pos); + + up_write(&root->kernfs_rwsem); +} - WARN_ON_ONCE(pos->parent && RB_EMPTY_NODE(&pos->rb)); - WARN_ON_ONCE(atomic_read(&pos->active) != KN_DEACTIVATED_BIAS); +/** + * kernfs_show - show or hide a node + * @kn: kernfs_node to show or hide + * @show: whether to show or hide + * + * If @show is %false, @kn is marked hidden and deactivated. A hidden node is + * ignored in future activaitons. If %true, the mark is removed and activation + * state is restored. This function won't implicitly activate a new node in a + * %KERNFS_ROOT_CREATE_DEACTIVATED root which hasn't been activated yet. + * + * To avoid recursion complexities, directories aren't supported for now. + */ +void kernfs_show(struct kernfs_node *kn, bool show) +{ + struct kernfs_root *root = kernfs_root(kn); - atomic_sub(KN_DEACTIVATED_BIAS, &pos->active); - pos->flags |= KERNFS_ACTIVATED; + if (WARN_ON_ONCE(kernfs_type(kn) == KERNFS_DIR)) + return; + + down_write(&root->kernfs_rwsem); + + if (show) { + kn->flags &= ~KERNFS_HIDDEN; + if (kn->flags & KERNFS_ACTIVATED) + kernfs_activate_one(kn); + } else { + kn->flags |= KERNFS_HIDDEN; + if (kernfs_active(kn)) + atomic_add(KN_DEACTIVATED_BIAS, &kn->active); + kernfs_drain(kn); } up_write(&root->kernfs_rwsem); @@ -1358,34 +1401,27 @@ static void __kernfs_remove(struct kernfs_node *kn) pr_debug("kernfs %s: removing\n", kn->name); - /* prevent any new usage under @kn by deactivating all nodes */ + /* prevent new usage by marking all nodes removing and deactivating */ pos = NULL; - while ((pos = kernfs_next_descendant_post(pos, kn))) + while ((pos = kernfs_next_descendant_post(pos, kn))) { + pos->flags |= KERNFS_REMOVING; if (kernfs_active(pos)) atomic_add(KN_DEACTIVATED_BIAS, &pos->active); + } /* deactivate and unlink the subtree node-by-node */ do { pos = kernfs_leftmost_descendant(kn); /* - * kernfs_drain() drops kernfs_rwsem temporarily and @pos's + * kernfs_drain() may drop kernfs_rwsem temporarily and @pos's * base ref could have been put by someone else by the time * the function returns. Make sure it doesn't go away * underneath us. */ kernfs_get(pos); - /* - * Drain iff @kn was activated. This avoids draining and - * its lockdep annotations for nodes which have never been - * activated and allows embedding kernfs_remove() in create - * error paths without worrying about draining. - */ - if (kn->flags & KERNFS_ACTIVATED) - kernfs_drain(pos); - else - WARN_ON_ONCE(atomic_read(&kn->active) != KN_DEACTIVATED_BIAS); + kernfs_drain(pos); /* * kernfs_unlink_sibling() succeeds once per node. Use it diff --git a/fs/kernfs/file.c b/fs/kernfs/file.c index b3ec34386b43..9ab6c92e02da 100644 --- a/fs/kernfs/file.c +++ b/fs/kernfs/file.c @@ -23,6 +23,8 @@ struct kernfs_open_node { atomic_t event; wait_queue_head_t poll; struct list_head files; /* goes through kernfs_open_file.list */ + unsigned int nr_mmapped; + unsigned int nr_to_release; }; /* @@ -57,31 +59,17 @@ static inline struct mutex *kernfs_open_file_mutex_lock(struct kernfs_node *kn) } /** - * kernfs_deref_open_node - Get kernfs_open_node corresponding to @kn. - * - * @of: associated kernfs_open_file instance. - * @kn: target kernfs_node. - * - * Fetch and return ->attr.open of @kn if @of->list is non empty. - * If @of->list is not empty we can safely assume that @of is on - * @kn->attr.open->files list and this guarantees that @kn->attr.open - * will not vanish i.e. dereferencing outside RCU read-side critical - * section is safe here. - * - * The caller needs to make sure that @of->list is not empty. + * of_on - Return the kernfs_open_node of the specified kernfs_open_file + * @of: taret kernfs_open_file */ -static struct kernfs_open_node * -kernfs_deref_open_node(struct kernfs_open_file *of, struct kernfs_node *kn) +static struct kernfs_open_node *of_on(struct kernfs_open_file *of) { - struct kernfs_open_node *on; - - on = rcu_dereference_check(kn->attr.open, !list_empty(&of->list)); - - return on; + return rcu_dereference_protected(of->kn->attr.open, + !list_empty(&of->list)); } /** - * kernfs_deref_open_node_protected - Get kernfs_open_node corresponding to @kn + * kernfs_deref_open_node_locked - Get kernfs_open_node corresponding to @kn * * @kn: target kernfs_node. * @@ -96,7 +84,7 @@ kernfs_deref_open_node(struct kernfs_open_file *of, struct kernfs_node *kn) * The caller needs to make sure that kernfs_open_file_mutex is held. */ static struct kernfs_open_node * -kernfs_deref_open_node_protected(struct kernfs_node *kn) +kernfs_deref_open_node_locked(struct kernfs_node *kn) { return rcu_dereference_protected(kn->attr.open, lockdep_is_held(kernfs_open_file_mutex_ptr(kn))); @@ -207,12 +195,8 @@ static void kernfs_seq_stop(struct seq_file *sf, void *v) static int kernfs_seq_show(struct seq_file *sf, void *v) { struct kernfs_open_file *of = sf->private; - struct kernfs_open_node *on = kernfs_deref_open_node(of, of->kn); - - if (!on) - return -EINVAL; - of->event = atomic_read(&on->event); + of->event = atomic_read(&of_on(of)->event); return of->kn->attr.ops->seq_show(sf, v); } @@ -235,7 +219,6 @@ static ssize_t kernfs_file_read_iter(struct kiocb *iocb, struct iov_iter *iter) struct kernfs_open_file *of = kernfs_of(iocb->ki_filp); ssize_t len = min_t(size_t, iov_iter_count(iter), PAGE_SIZE); const struct kernfs_ops *ops; - struct kernfs_open_node *on; char *buf; buf = of->prealloc_buf; @@ -257,14 +240,7 @@ static ssize_t kernfs_file_read_iter(struct kiocb *iocb, struct iov_iter *iter) goto out_free; } - on = kernfs_deref_open_node(of, of->kn); - if (!on) { - len = -EINVAL; - mutex_unlock(&of->mutex); - goto out_free; - } - - of->event = atomic_read(&on->event); + of->event = atomic_read(&of_on(of)->event); ops = kernfs_ops(of->kn); if (ops->read) @@ -553,6 +529,7 @@ static int kernfs_fop_mmap(struct file *file, struct vm_area_struct *vma) rc = 0; of->mmapped = true; + of_on(of)->nr_mmapped++; of->vm_ops = vma->vm_ops; vma->vm_ops = &kernfs_vm_ops; out_put: @@ -580,31 +557,30 @@ out_unlock: static int kernfs_get_open_node(struct kernfs_node *kn, struct kernfs_open_file *of) { - struct kernfs_open_node *on, *new_on = NULL; - struct mutex *mutex = NULL; + struct kernfs_open_node *on; + struct mutex *mutex; mutex = kernfs_open_file_mutex_lock(kn); - on = kernfs_deref_open_node_protected(kn); + on = kernfs_deref_open_node_locked(kn); - if (on) { - list_add_tail(&of->list, &on->files); - mutex_unlock(mutex); - return 0; - } else { + if (!on) { /* not there, initialize a new one */ - new_on = kmalloc(sizeof(*new_on), GFP_KERNEL); - if (!new_on) { + on = kzalloc(sizeof(*on), GFP_KERNEL); + if (!on) { mutex_unlock(mutex); return -ENOMEM; } - atomic_set(&new_on->event, 1); - init_waitqueue_head(&new_on->poll); - INIT_LIST_HEAD(&new_on->files); - list_add_tail(&of->list, &new_on->files); - rcu_assign_pointer(kn->attr.open, new_on); + atomic_set(&on->event, 1); + init_waitqueue_head(&on->poll); + INIT_LIST_HEAD(&on->files); + rcu_assign_pointer(kn->attr.open, on); } - mutex_unlock(mutex); + list_add_tail(&of->list, &on->files); + if (kn->flags & KERNFS_HAS_RELEASE) + on->nr_to_release++; + + mutex_unlock(mutex); return 0; } @@ -613,6 +589,7 @@ static int kernfs_get_open_node(struct kernfs_node *kn, * * @kn: target kernfs_node * @of: associated kernfs_open_file + * @open_failed: ->open() failed, cancel ->release() * * Unlink @of from list of @kn's associated open files. If list of * associated open files becomes empty, disassociate and free @@ -622,21 +599,30 @@ static int kernfs_get_open_node(struct kernfs_node *kn, * None. */ static void kernfs_unlink_open_file(struct kernfs_node *kn, - struct kernfs_open_file *of) + struct kernfs_open_file *of, + bool open_failed) { struct kernfs_open_node *on; - struct mutex *mutex = NULL; + struct mutex *mutex; mutex = kernfs_open_file_mutex_lock(kn); - on = kernfs_deref_open_node_protected(kn); + on = kernfs_deref_open_node_locked(kn); if (!on) { mutex_unlock(mutex); return; } - if (of) + if (of) { + if (kn->flags & KERNFS_HAS_RELEASE) { + WARN_ON_ONCE(of->released == open_failed); + if (open_failed) + on->nr_to_release--; + } + if (of->mmapped) + on->nr_mmapped--; list_del(&of->list); + } if (list_empty(&on->files)) { rcu_assign_pointer(kn->attr.open, NULL); @@ -763,7 +749,7 @@ static int kernfs_fop_open(struct inode *inode, struct file *file) return 0; err_put_node: - kernfs_unlink_open_file(kn, of); + kernfs_unlink_open_file(kn, of, true); err_seq_release: seq_release(inode, file); err_free: @@ -795,6 +781,7 @@ static void kernfs_release_file(struct kernfs_node *kn, */ kn->attr.ops->release(of); of->released = true; + of_on(of)->nr_to_release--; } } @@ -802,15 +789,16 @@ static int kernfs_fop_release(struct inode *inode, struct file *filp) { struct kernfs_node *kn = inode->i_private; struct kernfs_open_file *of = kernfs_of(filp); - struct mutex *mutex = NULL; if (kn->flags & KERNFS_HAS_RELEASE) { + struct mutex *mutex; + mutex = kernfs_open_file_mutex_lock(kn); kernfs_release_file(kn, of); mutex_unlock(mutex); } - kernfs_unlink_open_file(kn, of); + kernfs_unlink_open_file(kn, of, false); seq_release(inode, filp); kfree(of->prealloc_buf); kfree(of); @@ -818,28 +806,33 @@ static int kernfs_fop_release(struct inode *inode, struct file *filp) return 0; } -void kernfs_drain_open_files(struct kernfs_node *kn) +bool kernfs_should_drain_open_files(struct kernfs_node *kn) { struct kernfs_open_node *on; - struct kernfs_open_file *of; - struct mutex *mutex = NULL; - - if (!(kn->flags & (KERNFS_HAS_MMAP | KERNFS_HAS_RELEASE))) - return; + bool ret; /* - * lockless opportunistic check is safe below because no one is adding to - * ->attr.open at this point of time. This check allows early bail out - * if ->attr.open is already NULL. kernfs_unlink_open_file makes - * ->attr.open NULL only while holding kernfs_open_file_mutex so below - * check under kernfs_open_file_mutex_ptr(kn) will ensure bailing out if - * ->attr.open became NULL while waiting for the mutex. + * @kn being deactivated guarantees that @kn->attr.open can't change + * beneath us making the lockless test below safe. */ - if (!rcu_access_pointer(kn->attr.open)) - return; + WARN_ON_ONCE(atomic_read(&kn->active) != KN_DEACTIVATED_BIAS); + + rcu_read_lock(); + on = rcu_dereference(kn->attr.open); + ret = on && (on->nr_mmapped || on->nr_to_release); + rcu_read_unlock(); + + return ret; +} + +void kernfs_drain_open_files(struct kernfs_node *kn) +{ + struct kernfs_open_node *on; + struct kernfs_open_file *of; + struct mutex *mutex; mutex = kernfs_open_file_mutex_lock(kn); - on = kernfs_deref_open_node_protected(kn); + on = kernfs_deref_open_node_locked(kn); if (!on) { mutex_unlock(mutex); return; @@ -848,13 +841,17 @@ void kernfs_drain_open_files(struct kernfs_node *kn) list_for_each_entry(of, &on->files, list) { struct inode *inode = file_inode(of->file); - if (kn->flags & KERNFS_HAS_MMAP) + if (of->mmapped) { unmap_mapping_range(inode->i_mapping, 0, 0, 1); + of->mmapped = false; + on->nr_mmapped--; + } if (kn->flags & KERNFS_HAS_RELEASE) kernfs_release_file(kn, of); } + WARN_ON_ONCE(on->nr_mmapped || on->nr_to_release); mutex_unlock(mutex); } @@ -874,11 +871,7 @@ void kernfs_drain_open_files(struct kernfs_node *kn) */ __poll_t kernfs_generic_poll(struct kernfs_open_file *of, poll_table *wait) { - struct kernfs_node *kn = kernfs_dentry_node(of->file->f_path.dentry); - struct kernfs_open_node *on = kernfs_deref_open_node(of, kn); - - if (!on) - return EPOLLERR; + struct kernfs_open_node *on = of_on(of); poll_wait(of->file, &on->poll, wait); diff --git a/fs/kernfs/kernfs-internal.h b/fs/kernfs/kernfs-internal.h index 3ae214d02d44..fc5821effd97 100644 --- a/fs/kernfs/kernfs-internal.h +++ b/fs/kernfs/kernfs-internal.h @@ -157,6 +157,7 @@ struct kernfs_node *kernfs_new_node(struct kernfs_node *parent, */ extern const struct file_operations kernfs_file_fops; +bool kernfs_should_drain_open_files(struct kernfs_node *kn); void kernfs_drain_open_files(struct kernfs_node *kn); /* diff --git a/include/asm-generic/vmlinux.lds.h b/include/asm-generic/vmlinux.lds.h index 7515a465ec03..9b8bd5504ad9 100644 --- a/include/asm-generic/vmlinux.lds.h +++ b/include/asm-generic/vmlinux.lds.h @@ -345,6 +345,9 @@ *(__tracepoints) \ /* implement dynamic printk debug */ \ . = ALIGN(8); \ + __start___dyndbg_classes = .; \ + KEEP(*(__dyndbg_classes)) \ + __stop___dyndbg_classes = .; \ __start___dyndbg = .; \ KEEP(*(__dyndbg)) \ __stop___dyndbg = .; \ diff --git a/include/linux/cgroup.h b/include/linux/cgroup.h index ac5d0515680e..b0914aa26506 100644 --- a/include/linux/cgroup.h +++ b/include/linux/cgroup.h @@ -114,6 +114,7 @@ int cgroup_add_dfl_cftypes(struct cgroup_subsys *ss, struct cftype *cfts); int cgroup_add_legacy_cftypes(struct cgroup_subsys *ss, struct cftype *cfts); int cgroup_rm_cftypes(struct cftype *cfts); void cgroup_file_notify(struct cgroup_file *cfile); +void cgroup_file_show(struct cgroup_file *cfile, bool show); int task_cgroup_path(struct task_struct *task, char *buf, size_t buflen); int cgroupstats_build(struct cgroupstats *stats, struct dentry *dentry); diff --git a/include/linux/dynamic_debug.h b/include/linux/dynamic_debug.h index dce631e678dd..41682278d2e8 100644 --- a/include/linux/dynamic_debug.h +++ b/include/linux/dynamic_debug.h @@ -6,6 +6,8 @@ #include <linux/jump_label.h> #endif +#include <linux/build_bug.h> + /* * An instance of this structure is created in a special * ELF section at every dynamic debug callsite. At runtime, @@ -21,6 +23,9 @@ struct _ddebug { const char *filename; const char *format; unsigned int lineno:18; +#define CLS_BITS 6 + unsigned int class_id:CLS_BITS; +#define _DPRINTK_CLASS_DFLT ((1 << CLS_BITS) - 1) /* * The flags field controls the behaviour at the callsite. * The bits here are changed dynamically when the user @@ -51,15 +56,82 @@ struct _ddebug { #endif } __attribute__((aligned(8))); - +enum class_map_type { + DD_CLASS_TYPE_DISJOINT_BITS, + /** + * DD_CLASS_TYPE_DISJOINT_BITS: classes are independent, one per bit. + * expecting hex input. Built for drm.debug, basis for other types. + */ + DD_CLASS_TYPE_LEVEL_NUM, + /** + * DD_CLASS_TYPE_LEVEL_NUM: input is numeric level, 0-N. + * N turns on just bits N-1 .. 0, so N=0 turns all bits off. + */ + DD_CLASS_TYPE_DISJOINT_NAMES, + /** + * DD_CLASS_TYPE_DISJOINT_NAMES: input is a CSV of [+-]CLASS_NAMES, + * classes are independent, like _DISJOINT_BITS. + */ + DD_CLASS_TYPE_LEVEL_NAMES, + /** + * DD_CLASS_TYPE_LEVEL_NAMES: input is a CSV of [+-]CLASS_NAMES, + * intended for names like: INFO,DEBUG,TRACE, with a module prefix + * avoid EMERG,ALERT,CRIT,ERR,WARNING: they're not debug + */ +}; + +struct ddebug_class_map { + struct list_head link; + struct module *mod; + const char *mod_name; /* needed for builtins */ + const char **class_names; + const int length; + const int base; /* index of 1st .class_id, allows split/shared space */ + enum class_map_type map_type; +}; + +/** + * DECLARE_DYNDBG_CLASSMAP - declare classnames known by a module + * @_var: a struct ddebug_class_map, passed to module_param_cb + * @_type: enum class_map_type, chooses bits/verbose, numeric/symbolic + * @_base: offset of 1st class-name. splits .class_id space + * @classes: class-names used to control class'd prdbgs + */ +#define DECLARE_DYNDBG_CLASSMAP(_var, _maptype, _base, ...) \ + static const char *_var##_classnames[] = { __VA_ARGS__ }; \ + static struct ddebug_class_map __aligned(8) __used \ + __section("__dyndbg_classes") _var = { \ + .mod = THIS_MODULE, \ + .mod_name = KBUILD_MODNAME, \ + .base = _base, \ + .map_type = _maptype, \ + .length = NUM_TYPE_ARGS(char*, __VA_ARGS__), \ + .class_names = _var##_classnames, \ + } +#define NUM_TYPE_ARGS(eltype, ...) \ + (sizeof((eltype[]){__VA_ARGS__}) / sizeof(eltype)) + +/* encapsulate linker provided built-in (or module) dyndbg data */ +struct _ddebug_info { + struct _ddebug *descs; + struct ddebug_class_map *classes; + unsigned int num_descs; + unsigned int num_classes; +}; + +struct ddebug_class_param { + union { + unsigned long *bits; + unsigned int *lvl; + }; + char flags[8]; + const struct ddebug_class_map *map; +}; #if defined(CONFIG_DYNAMIC_DEBUG_CORE) -/* exported for module authors to exercise >control */ -int dynamic_debug_exec_queries(const char *query, const char *modname); +int ddebug_add_module(struct _ddebug_info *dyndbg, const char *modname); -int ddebug_add_module(struct _ddebug *tab, unsigned int n, - const char *modname); extern int ddebug_remove_module(const char *mod_name); extern __printf(2, 3) void __dynamic_pr_debug(struct _ddebug *descriptor, const char *fmt, ...); @@ -87,7 +159,7 @@ void __dynamic_ibdev_dbg(struct _ddebug *descriptor, const struct ib_device *ibdev, const char *fmt, ...); -#define DEFINE_DYNAMIC_DEBUG_METADATA(name, fmt) \ +#define DEFINE_DYNAMIC_DEBUG_METADATA_CLS(name, cls, fmt) \ static struct _ddebug __aligned(8) \ __section("__dyndbg") name = { \ .modname = KBUILD_MODNAME, \ @@ -96,8 +168,14 @@ void __dynamic_ibdev_dbg(struct _ddebug *descriptor, .format = (fmt), \ .lineno = __LINE__, \ .flags = _DPRINTK_FLAGS_DEFAULT, \ + .class_id = cls, \ _DPRINTK_KEY_INIT \ - } + }; \ + BUILD_BUG_ON_MSG(cls > _DPRINTK_CLASS_DFLT, \ + "classid value overflow") + +#define DEFINE_DYNAMIC_DEBUG_METADATA(name, fmt) \ + DEFINE_DYNAMIC_DEBUG_METADATA_CLS(name, _DPRINTK_CLASS_DFLT, fmt) #ifdef CONFIG_JUMP_LABEL @@ -128,17 +206,34 @@ void __dynamic_ibdev_dbg(struct _ddebug *descriptor, #endif /* CONFIG_JUMP_LABEL */ -#define __dynamic_func_call(id, fmt, func, ...) do { \ - DEFINE_DYNAMIC_DEBUG_METADATA(id, fmt); \ - if (DYNAMIC_DEBUG_BRANCH(id)) \ - func(&id, ##__VA_ARGS__); \ -} while (0) - -#define __dynamic_func_call_no_desc(id, fmt, func, ...) do { \ - DEFINE_DYNAMIC_DEBUG_METADATA(id, fmt); \ +/* + * Factory macros: ($prefix)dynamic_func_call($suffix) + * + * Lower layer (with __ prefix) gets the callsite metadata, and wraps + * the func inside a debug-branch/static-key construct. Upper layer + * (with _ prefix) does the UNIQUE_ID once, so that lower can ref the + * name/label multiple times, and tie the elements together. + * Multiple flavors: + * (|_cls): adds in _DPRINT_CLASS_DFLT as needed + * (|_no_desc): former gets callsite descriptor as 1st arg (for prdbgs) + */ +#define __dynamic_func_call_cls(id, cls, fmt, func, ...) do { \ + DEFINE_DYNAMIC_DEBUG_METADATA_CLS(id, cls, fmt); \ if (DYNAMIC_DEBUG_BRANCH(id)) \ - func(__VA_ARGS__); \ + func(&id, ##__VA_ARGS__); \ +} while (0) +#define __dynamic_func_call(id, fmt, func, ...) \ + __dynamic_func_call_cls(id, _DPRINTK_CLASS_DFLT, fmt, \ + func, ##__VA_ARGS__) + +#define __dynamic_func_call_cls_no_desc(id, cls, fmt, func, ...) do { \ + DEFINE_DYNAMIC_DEBUG_METADATA_CLS(id, cls, fmt); \ + if (DYNAMIC_DEBUG_BRANCH(id)) \ + func(__VA_ARGS__); \ } while (0) +#define __dynamic_func_call_no_desc(id, fmt, func, ...) \ + __dynamic_func_call_cls_no_desc(id, _DPRINTK_CLASS_DFLT, \ + fmt, func, ##__VA_ARGS__) /* * "Factory macro" for generating a call to func, guarded by a @@ -148,22 +243,33 @@ void __dynamic_ibdev_dbg(struct _ddebug *descriptor, * the varargs. Note that fmt is repeated in invocations of this * macro. */ +#define _dynamic_func_call_cls(cls, fmt, func, ...) \ + __dynamic_func_call_cls(__UNIQUE_ID(ddebug), cls, fmt, func, ##__VA_ARGS__) #define _dynamic_func_call(fmt, func, ...) \ - __dynamic_func_call(__UNIQUE_ID(ddebug), fmt, func, ##__VA_ARGS__) + _dynamic_func_call_cls(_DPRINTK_CLASS_DFLT, fmt, func, ##__VA_ARGS__) + /* * A variant that does the same, except that the descriptor is not * passed as the first argument to the function; it is only called * with precisely the macro's varargs. */ -#define _dynamic_func_call_no_desc(fmt, func, ...) \ - __dynamic_func_call_no_desc(__UNIQUE_ID(ddebug), fmt, func, ##__VA_ARGS__) +#define _dynamic_func_call_cls_no_desc(cls, fmt, func, ...) \ + __dynamic_func_call_cls_no_desc(__UNIQUE_ID(ddebug), cls, fmt, \ + func, ##__VA_ARGS__) +#define _dynamic_func_call_no_desc(fmt, func, ...) \ + _dynamic_func_call_cls_no_desc(_DPRINTK_CLASS_DFLT, fmt, \ + func, ##__VA_ARGS__) + +#define dynamic_pr_debug_cls(cls, fmt, ...) \ + _dynamic_func_call_cls(cls, fmt, __dynamic_pr_debug, \ + pr_fmt(fmt), ##__VA_ARGS__) #define dynamic_pr_debug(fmt, ...) \ - _dynamic_func_call(fmt, __dynamic_pr_debug, \ + _dynamic_func_call(fmt, __dynamic_pr_debug, \ pr_fmt(fmt), ##__VA_ARGS__) #define dynamic_dev_dbg(dev, fmt, ...) \ - _dynamic_func_call(fmt,__dynamic_dev_dbg, \ + _dynamic_func_call(fmt, __dynamic_dev_dbg, \ dev, fmt, ##__VA_ARGS__) #define dynamic_netdev_dbg(dev, fmt, ...) \ @@ -181,14 +287,24 @@ void __dynamic_ibdev_dbg(struct _ddebug *descriptor, KERN_DEBUG, prefix_str, prefix_type, \ rowsize, groupsize, buf, len, ascii) +struct kernel_param; +int param_set_dyndbg_classes(const char *instr, const struct kernel_param *kp); +int param_get_dyndbg_classes(char *buffer, const struct kernel_param *kp); + +/* for test only, generally expect drm.debug style macro wrappers */ +#define __pr_debug_cls(cls, fmt, ...) do { \ + BUILD_BUG_ON_MSG(!__builtin_constant_p(cls), \ + "expecting constant class int/enum"); \ + dynamic_pr_debug_cls(cls, fmt, ##__VA_ARGS__); \ + } while (0) + #else /* !CONFIG_DYNAMIC_DEBUG_CORE */ #include <linux/string.h> #include <linux/errno.h> #include <linux/printk.h> -static inline int ddebug_add_module(struct _ddebug *tab, unsigned int n, - const char *modname) +static inline int ddebug_add_module(struct _ddebug_info *dinfo, const char *modname) { return 0; } @@ -201,7 +317,7 @@ static inline int ddebug_remove_module(const char *mod) static inline int ddebug_dyndbg_module_param_cb(char *param, char *val, const char *modname) { - if (strstr(param, "dyndbg")) { + if (!strcmp(param, "dyndbg")) { /* avoid pr_warn(), which wants pr_fmt() fully defined */ printk(KERN_WARNING "dyndbg param is supported only in " "CONFIG_DYNAMIC_DEBUG builds\n"); @@ -221,12 +337,14 @@ static inline int ddebug_dyndbg_module_param_cb(char *param, char *val, rowsize, groupsize, buf, len, ascii); \ } while (0) -static inline int dynamic_debug_exec_queries(const char *query, const char *modname) -{ - pr_warn("kernel not built with CONFIG_DYNAMIC_DEBUG_CORE\n"); - return 0; -} +struct kernel_param; +static inline int param_set_dyndbg_classes(const char *instr, const struct kernel_param *kp) +{ return 0; } +static inline int param_get_dyndbg_classes(char *buffer, const struct kernel_param *kp) +{ return 0; } #endif /* !CONFIG_DYNAMIC_DEBUG_CORE */ +extern const struct kernel_param_ops param_ops_dyndbg_classes; + #endif diff --git a/include/linux/io.h b/include/linux/io.h index 5fc800390fe4..308f4f0cfb93 100644 --- a/include/linux/io.h +++ b/include/linux/io.h @@ -59,8 +59,6 @@ void __iomem *devm_ioremap_uc(struct device *dev, resource_size_t offset, resource_size_t size); void __iomem *devm_ioremap_wc(struct device *dev, resource_size_t offset, resource_size_t size); -void __iomem *devm_ioremap_np(struct device *dev, resource_size_t offset, - resource_size_t size); void devm_iounmap(struct device *dev, void __iomem *addr); int check_signature(const volatile void __iomem *io_addr, const unsigned char *signature, int length); diff --git a/include/linux/kernfs.h b/include/linux/kernfs.h index 367044d7708c..73f5c120def8 100644 --- a/include/linux/kernfs.h +++ b/include/linux/kernfs.h @@ -108,10 +108,12 @@ enum kernfs_node_flag { KERNFS_HAS_SEQ_SHOW = 0x0040, KERNFS_HAS_MMAP = 0x0080, KERNFS_LOCKDEP = 0x0100, + KERNFS_HIDDEN = 0x0200, KERNFS_SUICIDAL = 0x0400, KERNFS_SUICIDED = 0x0800, KERNFS_EMPTY_DIR = 0x1000, KERNFS_HAS_RELEASE = 0x2000, + KERNFS_REMOVING = 0x4000, }; /* @flags for kernfs_create_root() */ @@ -429,6 +431,7 @@ struct kernfs_node *kernfs_create_link(struct kernfs_node *parent, const char *name, struct kernfs_node *target); void kernfs_activate(struct kernfs_node *kn); +void kernfs_show(struct kernfs_node *kn, bool show); void kernfs_remove(struct kernfs_node *kn); void kernfs_break_active_protection(struct kernfs_node *kn); void kernfs_unbreak_active_protection(struct kernfs_node *kn); diff --git a/kernel/cgroup/cgroup.c b/kernel/cgroup/cgroup.c index e4bb5d57f4d1..718a70c01c04 100644 --- a/kernel/cgroup/cgroup.c +++ b/kernel/cgroup/cgroup.c @@ -4372,6 +4372,26 @@ void cgroup_file_notify(struct cgroup_file *cfile) } /** + * cgroup_file_show - show or hide a hidden cgroup file + * @cfile: target cgroup_file obtained by setting cftype->file_offset + * @show: whether to show or hide + */ +void cgroup_file_show(struct cgroup_file *cfile, bool show) +{ + struct kernfs_node *kn; + + spin_lock_irq(&cgroup_file_kn_lock); + kn = cfile->kn; + kernfs_get(kn); + spin_unlock_irq(&cgroup_file_kn_lock); + + if (kn) + kernfs_show(kn, show); + + kernfs_put(kn); +} + +/** * css_next_child - find the next child of a given css * @pos: the current position (%NULL to initiate traversal) * @parent: css whose children to walk diff --git a/kernel/module/internal.h b/kernel/module/internal.h index 680d980a4fb2..2e2bf236f558 100644 --- a/kernel/module/internal.h +++ b/kernel/module/internal.h @@ -53,6 +53,7 @@ extern const struct kernel_symbol __stop___ksymtab_gpl[]; extern const s32 __start___kcrctab[]; extern const s32 __start___kcrctab_gpl[]; +#include <linux/dynamic_debug.h> struct load_info { const char *name; /* pointer to module in temporary copy, freed at end of load_module() */ @@ -62,8 +63,7 @@ struct load_info { Elf_Shdr *sechdrs; char *secstrings, *strtab; unsigned long symoffs, stroffs, init_typeoffs, core_typeoffs; - struct _ddebug *debug; - unsigned int num_debug; + struct _ddebug_info dyndbg; bool sig_ok; #ifdef CONFIG_KALLSYMS unsigned long mod_kallsyms_init_off; diff --git a/kernel/module/main.c b/kernel/module/main.c index a4e4d84b6f4e..6aa6153aa6e0 100644 --- a/kernel/module/main.c +++ b/kernel/module/main.c @@ -1598,16 +1598,16 @@ static void free_modinfo(struct module *mod) } } -static void dynamic_debug_setup(struct module *mod, struct _ddebug *debug, unsigned int num) +static void dynamic_debug_setup(struct module *mod, struct _ddebug_info *dyndbg) { - if (!debug) + if (!dyndbg->num_descs) return; - ddebug_add_module(debug, num, mod->name); + ddebug_add_module(dyndbg, mod->name); } -static void dynamic_debug_remove(struct module *mod, struct _ddebug *debug) +static void dynamic_debug_remove(struct module *mod, struct _ddebug_info *dyndbg) { - if (debug) + if (dyndbg->num_descs) ddebug_remove_module(mod->name); } @@ -2111,8 +2111,10 @@ static int find_module_sections(struct module *mod, struct load_info *info) if (section_addr(info, "__obsparm")) pr_warn("%s: Ignoring obsolete parameters\n", mod->name); - info->debug = section_objs(info, "__dyndbg", - sizeof(*info->debug), &info->num_debug); + info->dyndbg.descs = section_objs(info, "__dyndbg", + sizeof(*info->dyndbg.descs), &info->dyndbg.num_descs); + info->dyndbg.classes = section_objs(info, "__dyndbg_classes", + sizeof(*info->dyndbg.classes), &info->dyndbg.num_classes); return 0; } @@ -2807,7 +2809,7 @@ static int load_module(struct load_info *info, const char __user *uargs, } init_build_id(mod, info); - dynamic_debug_setup(mod, info->debug, info->num_debug); + dynamic_debug_setup(mod, &info->dyndbg); /* Ftrace init must be called in the MODULE_STATE_UNFORMED state */ ftrace_module_init(mod); @@ -2871,7 +2873,7 @@ static int load_module(struct load_info *info, const char __user *uargs, ddebug_cleanup: ftrace_release_mod(mod); - dynamic_debug_remove(mod, info->debug); + dynamic_debug_remove(mod, &info->dyndbg); synchronize_rcu(); kfree(mod->args); free_arch_cleanup: diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug index bcbe60d6c80c..75f2eaf4f110 100644 --- a/lib/Kconfig.debug +++ b/lib/Kconfig.debug @@ -2549,6 +2549,16 @@ config TEST_STATIC_KEYS If unsure, say N. +config TEST_DYNAMIC_DEBUG + tristate "Test DYNAMIC_DEBUG" + depends on DYNAMIC_DEBUG + help + This module registers a tracer callback to count enabled + pr_debugs in a 'do_debugging' function, then alters their + enablements, calls the function, and compares counts. + + If unsure, say N. + config TEST_KMOD tristate "kmod stress tester" depends on m diff --git a/lib/Makefile b/lib/Makefile index ffabc30a27d4..cd1e4272c6f9 100644 --- a/lib/Makefile +++ b/lib/Makefile @@ -83,6 +83,7 @@ obj-$(CONFIG_TEST_SORT) += test_sort.o obj-$(CONFIG_TEST_USER_COPY) += test_user_copy.o obj-$(CONFIG_TEST_STATIC_KEYS) += test_static_keys.o obj-$(CONFIG_TEST_STATIC_KEYS) += test_static_key_base.o +obj-$(CONFIG_TEST_DYNAMIC_DEBUG) += test_dynamic_debug.o obj-$(CONFIG_TEST_PRINTF) += test_printf.o obj-$(CONFIG_TEST_SCANF) += test_scanf.o obj-$(CONFIG_TEST_BITMAP) += test_bitmap.o diff --git a/lib/devres.c b/lib/devres.c index 55eb07e80cbb..6baf43902ead 100644 --- a/lib/devres.c +++ b/lib/devres.c @@ -104,21 +104,6 @@ void __iomem *devm_ioremap_wc(struct device *dev, resource_size_t offset, EXPORT_SYMBOL(devm_ioremap_wc); /** - * devm_ioremap_np - Managed ioremap_np() - * @dev: Generic device to remap IO address for - * @offset: Resource address to map - * @size: Size of map - * - * Managed ioremap_np(). Map is automatically unmapped on driver detach. - */ -void __iomem *devm_ioremap_np(struct device *dev, resource_size_t offset, - resource_size_t size) -{ - return __devm_ioremap(dev, offset, size, DEVM_IOREMAP_NP); -} -EXPORT_SYMBOL(devm_ioremap_np); - -/** * devm_iounmap - Managed iounmap() * @dev: Generic device to unmap for * @addr: Address to unmap diff --git a/lib/dynamic_debug.c b/lib/dynamic_debug.c index dd7f56af9aed..009f2ead09c1 100644 --- a/lib/dynamic_debug.c +++ b/lib/dynamic_debug.c @@ -41,9 +41,11 @@ extern struct _ddebug __start___dyndbg[]; extern struct _ddebug __stop___dyndbg[]; +extern struct ddebug_class_map __start___dyndbg_classes[]; +extern struct ddebug_class_map __stop___dyndbg_classes[]; struct ddebug_table { - struct list_head link; + struct list_head link, maps; const char *mod_name; unsigned int num_ddebugs; struct _ddebug *ddebugs; @@ -54,12 +56,13 @@ struct ddebug_query { const char *module; const char *function; const char *format; + const char *class_string; unsigned int first_lineno, last_lineno; }; struct ddebug_iter { struct ddebug_table *table; - unsigned int idx; + int idx; }; struct flag_settings { @@ -134,15 +137,33 @@ static void vpr_info_dq(const struct ddebug_query *query, const char *msg) fmtlen--; } - v3pr_info("%s: func=\"%s\" file=\"%s\" module=\"%s\" format=\"%.*s\" lineno=%u-%u\n", - msg, - query->function ?: "", - query->filename ?: "", - query->module ?: "", - fmtlen, query->format ?: "", - query->first_lineno, query->last_lineno); + v3pr_info("%s: func=\"%s\" file=\"%s\" module=\"%s\" format=\"%.*s\" lineno=%u-%u class=%s\n", + msg, + query->function ?: "", + query->filename ?: "", + query->module ?: "", + fmtlen, query->format ?: "", + query->first_lineno, query->last_lineno, query->class_string); } +static struct ddebug_class_map *ddebug_find_valid_class(struct ddebug_table const *dt, + const char *class_string, int *class_id) +{ + struct ddebug_class_map *map; + int idx; + + list_for_each_entry(map, &dt->maps, link) { + idx = match_string(map->class_names, map->length, class_string); + if (idx >= 0) { + *class_id = idx + map->base; + return map; + } + } + *class_id = -ENOENT; + return NULL; +} + +#define __outvar /* filled by callee */ /* * Search the tables for _ddebug's which match the given `query' and * apply the `flags' and `mask' to them. Returns number of matching @@ -156,7 +177,9 @@ static int ddebug_change(const struct ddebug_query *query, struct ddebug_table *dt; unsigned int newflags; unsigned int nfound = 0; - struct flagsbuf fbuf; + struct flagsbuf fbuf, nbuf; + struct ddebug_class_map *map = NULL; + int __outvar valid_class; /* search for matching ddebugs */ mutex_lock(&ddebug_lock); @@ -167,9 +190,22 @@ static int ddebug_change(const struct ddebug_query *query, !match_wildcard(query->module, dt->mod_name)) continue; + if (query->class_string) { + map = ddebug_find_valid_class(dt, query->class_string, &valid_class); + if (!map) + continue; + } else { + /* constrain query, do not touch class'd callsites */ + valid_class = _DPRINTK_CLASS_DFLT; + } + for (i = 0; i < dt->num_ddebugs; i++) { struct _ddebug *dp = &dt->ddebugs[i]; + /* match site against query-class */ + if (dp->class_id != valid_class) + continue; + /* match against the source filename */ if (query->filename && !match_wildcard(query->filename, dp->filename) && @@ -211,16 +247,18 @@ static int ddebug_change(const struct ddebug_query *query, continue; #ifdef CONFIG_JUMP_LABEL if (dp->flags & _DPRINTK_FLAGS_PRINT) { - if (!(modifiers->flags & _DPRINTK_FLAGS_PRINT)) + if (!(newflags & _DPRINTK_FLAGS_PRINT)) static_branch_disable(&dp->key.dd_key_true); - } else if (modifiers->flags & _DPRINTK_FLAGS_PRINT) + } else if (newflags & _DPRINTK_FLAGS_PRINT) { static_branch_enable(&dp->key.dd_key_true); + } #endif + v4pr_info("changed %s:%d [%s]%s %s => %s\n", + trim_prefix(dp->filename), dp->lineno, + dt->mod_name, dp->function, + ddebug_describe_flags(dp->flags, &fbuf), + ddebug_describe_flags(newflags, &nbuf)); dp->flags = newflags; - v4pr_info("changed %s:%d [%s]%s =%s\n", - trim_prefix(dp->filename), dp->lineno, - dt->mod_name, dp->function, - ddebug_describe_flags(dp->flags, &fbuf)); } } mutex_unlock(&ddebug_lock); @@ -383,10 +421,6 @@ static int ddebug_parse_query(char *words[], int nwords, return -EINVAL; } - if (modname) - /* support $modname.dyndbg=<multiple queries> */ - query->module = modname; - for (i = 0; i < nwords; i += 2) { char *keyword = words[i]; char *arg = words[i+1]; @@ -420,6 +454,8 @@ static int ddebug_parse_query(char *words[], int nwords, } else if (!strcmp(keyword, "line")) { if (parse_linerange(query, arg)) return -EINVAL; + } else if (!strcmp(keyword, "class")) { + rc = check_set(&query->class_string, arg, "class"); } else { pr_err("unknown keyword \"%s\"\n", keyword); return -EINVAL; @@ -427,6 +463,13 @@ static int ddebug_parse_query(char *words[], int nwords, if (rc) return rc; } + if (!query->module && modname) + /* + * support $modname.dyndbg=<multiple queries>, when + * not given in the query itself + */ + query->module = modname; + vpr_info_dq(query, "parsed"); return 0; } @@ -553,34 +596,217 @@ static int ddebug_exec_queries(char *query, const char *modname) return nfound; } +/* apply a new bitmap to the sys-knob's current bit-state */ +static int ddebug_apply_class_bitmap(const struct ddebug_class_param *dcp, + unsigned long *new_bits, unsigned long *old_bits) +{ +#define QUERY_SIZE 128 + char query[QUERY_SIZE]; + const struct ddebug_class_map *map = dcp->map; + int matches = 0; + int bi, ct; + + v2pr_info("apply: 0x%lx to: 0x%lx\n", *new_bits, *old_bits); + + for (bi = 0; bi < map->length; bi++) { + if (test_bit(bi, new_bits) == test_bit(bi, old_bits)) + continue; + + snprintf(query, QUERY_SIZE, "class %s %c%s", map->class_names[bi], + test_bit(bi, new_bits) ? '+' : '-', dcp->flags); + + ct = ddebug_exec_queries(query, NULL); + matches += ct; + + v2pr_info("bit_%d: %d matches on class: %s -> 0x%lx\n", bi, + ct, map->class_names[bi], *new_bits); + } + return matches; +} + +/* stub to later conditionally add "$module." prefix where not already done */ +#define KP_NAME(kp) kp->name + +#define CLASSMAP_BITMASK(width) ((1UL << (width)) - 1) + +/* accept comma-separated-list of [+-] classnames */ +static int param_set_dyndbg_classnames(const char *instr, const struct kernel_param *kp) +{ + const struct ddebug_class_param *dcp = kp->arg; + const struct ddebug_class_map *map = dcp->map; + unsigned long curr_bits, old_bits; + char *cl_str, *p, *tmp; + int cls_id, totct = 0; + bool wanted; + + cl_str = tmp = kstrdup(instr, GFP_KERNEL); + p = strchr(cl_str, '\n'); + if (p) + *p = '\0'; + + /* start with previously set state-bits, then modify */ + curr_bits = old_bits = *dcp->bits; + vpr_info("\"%s\" > %s:0x%lx\n", cl_str, KP_NAME(kp), curr_bits); + + for (; cl_str; cl_str = p) { + p = strchr(cl_str, ','); + if (p) + *p++ = '\0'; + + if (*cl_str == '-') { + wanted = false; + cl_str++; + } else { + wanted = true; + if (*cl_str == '+') + cl_str++; + } + cls_id = match_string(map->class_names, map->length, cl_str); + if (cls_id < 0) { + pr_err("%s unknown to %s\n", cl_str, KP_NAME(kp)); + continue; + } + + /* have one or more valid class_ids of one *_NAMES type */ + switch (map->map_type) { + case DD_CLASS_TYPE_DISJOINT_NAMES: + /* the +/- pertains to a single bit */ + if (test_bit(cls_id, &curr_bits) == wanted) { + v3pr_info("no change on %s\n", cl_str); + continue; + } + curr_bits ^= BIT(cls_id); + totct += ddebug_apply_class_bitmap(dcp, &curr_bits, dcp->bits); + *dcp->bits = curr_bits; + v2pr_info("%s: changed bit %d:%s\n", KP_NAME(kp), cls_id, + map->class_names[cls_id]); + break; + case DD_CLASS_TYPE_LEVEL_NAMES: + /* cls_id = N in 0..max. wanted +/- determines N or N-1 */ + old_bits = CLASSMAP_BITMASK(*dcp->lvl); + curr_bits = CLASSMAP_BITMASK(cls_id + (wanted ? 1 : 0 )); + + totct += ddebug_apply_class_bitmap(dcp, &curr_bits, &old_bits); + *dcp->lvl = (cls_id + (wanted ? 1 : 0)); + v2pr_info("%s: changed bit-%d: \"%s\" %lx->%lx\n", KP_NAME(kp), cls_id, + map->class_names[cls_id], old_bits, curr_bits); + break; + default: + pr_err("illegal map-type value %d\n", map->map_type); + } + } + kfree(tmp); + vpr_info("total matches: %d\n", totct); + return 0; +} + /** - * dynamic_debug_exec_queries - select and change dynamic-debug prints - * @query: query-string described in admin-guide/dynamic-debug-howto - * @modname: string containing module name, usually &module.mod_name + * param_set_dyndbg_classes - class FOO >control + * @instr: string echo>d to sysfs, input depends on map_type + * @kp: kp->arg has state: bits/lvl, map, map_type + * + * Enable/disable prdbgs by their class, as given in the arguments to + * DECLARE_DYNDBG_CLASSMAP. For LEVEL map-types, enforce relative + * levels by bitpos. * - * This uses the >/proc/dynamic_debug/control reader, allowing module - * authors to modify their dynamic-debug callsites. The modname is - * canonically struct module.mod_name, but can also be null or a - * module-wildcard, for example: "drm*". + * Returns: 0 or <0 if error. */ -int dynamic_debug_exec_queries(const char *query, const char *modname) +int param_set_dyndbg_classes(const char *instr, const struct kernel_param *kp) { - int rc; - char *qry; /* writable copy of query */ - - if (!query) { - pr_err("non-null query/command string expected\n"); + const struct ddebug_class_param *dcp = kp->arg; + const struct ddebug_class_map *map = dcp->map; + unsigned long inrep, new_bits, old_bits; + int rc, totct = 0; + + switch (map->map_type) { + + case DD_CLASS_TYPE_DISJOINT_NAMES: + case DD_CLASS_TYPE_LEVEL_NAMES: + /* handle [+-]classnames list separately, we are done here */ + return param_set_dyndbg_classnames(instr, kp); + + case DD_CLASS_TYPE_DISJOINT_BITS: + case DD_CLASS_TYPE_LEVEL_NUM: + /* numeric input, accept and fall-thru */ + rc = kstrtoul(instr, 0, &inrep); + if (rc) { + pr_err("expecting numeric input: %s > %s\n", instr, KP_NAME(kp)); + return -EINVAL; + } + break; + default: + pr_err("%s: bad map type: %d\n", KP_NAME(kp), map->map_type); return -EINVAL; } - qry = kstrndup(query, PAGE_SIZE, GFP_KERNEL); - if (!qry) - return -ENOMEM; - rc = ddebug_exec_queries(qry, modname); - kfree(qry); - return rc; + /* only _BITS,_NUM (numeric) map-types get here */ + switch (map->map_type) { + case DD_CLASS_TYPE_DISJOINT_BITS: + /* expect bits. mask and warn if too many */ + if (inrep & ~CLASSMAP_BITMASK(map->length)) { + pr_warn("%s: input: 0x%lx exceeds mask: 0x%lx, masking\n", + KP_NAME(kp), inrep, CLASSMAP_BITMASK(map->length)); + inrep &= CLASSMAP_BITMASK(map->length); + } + v2pr_info("bits:%lx > %s\n", inrep, KP_NAME(kp)); + totct += ddebug_apply_class_bitmap(dcp, &inrep, dcp->bits); + *dcp->bits = inrep; + break; + case DD_CLASS_TYPE_LEVEL_NUM: + /* input is bitpos, of highest verbosity to be enabled */ + if (inrep > map->length) { + pr_warn("%s: level:%ld exceeds max:%d, clamping\n", + KP_NAME(kp), inrep, map->length); + inrep = map->length; + } + old_bits = CLASSMAP_BITMASK(*dcp->lvl); + new_bits = CLASSMAP_BITMASK(inrep); + v2pr_info("lvl:%ld bits:0x%lx > %s\n", inrep, new_bits, KP_NAME(kp)); + totct += ddebug_apply_class_bitmap(dcp, &new_bits, &old_bits); + *dcp->lvl = inrep; + break; + default: + pr_warn("%s: bad map type: %d\n", KP_NAME(kp), map->map_type); + } + vpr_info("%s: total matches: %d\n", KP_NAME(kp), totct); + return 0; +} +EXPORT_SYMBOL(param_set_dyndbg_classes); + +/** + * param_get_dyndbg_classes - classes reader + * @buffer: string description of controlled bits -> classes + * @kp: kp->arg has state: bits, map + * + * Reads last written state, underlying prdbg state may have been + * altered by direct >control. Displays 0x for DISJOINT, 0-N for + * LEVEL Returns: #chars written or <0 on error + */ +int param_get_dyndbg_classes(char *buffer, const struct kernel_param *kp) +{ + const struct ddebug_class_param *dcp = kp->arg; + const struct ddebug_class_map *map = dcp->map; + + switch (map->map_type) { + + case DD_CLASS_TYPE_DISJOINT_NAMES: + case DD_CLASS_TYPE_DISJOINT_BITS: + return scnprintf(buffer, PAGE_SIZE, "0x%lx\n", *dcp->bits); + + case DD_CLASS_TYPE_LEVEL_NAMES: + case DD_CLASS_TYPE_LEVEL_NUM: + return scnprintf(buffer, PAGE_SIZE, "%d\n", *dcp->lvl); + default: + return -1; + } } -EXPORT_SYMBOL_GPL(dynamic_debug_exec_queries); +EXPORT_SYMBOL(param_get_dyndbg_classes); + +const struct kernel_param_ops param_ops_dyndbg_classes = { + .set = param_set_dyndbg_classes, + .get = param_get_dyndbg_classes, +}; +EXPORT_SYMBOL(param_ops_dyndbg_classes); #define PREFIX_SIZE 64 @@ -803,13 +1029,12 @@ static struct _ddebug *ddebug_iter_first(struct ddebug_iter *iter) { if (list_empty(&ddebug_tables)) { iter->table = NULL; - iter->idx = 0; return NULL; } iter->table = list_entry(ddebug_tables.next, struct ddebug_table, link); - iter->idx = 0; - return &iter->table->ddebugs[iter->idx]; + iter->idx = iter->table->num_ddebugs; + return &iter->table->ddebugs[--iter->idx]; } /* @@ -822,15 +1047,16 @@ static struct _ddebug *ddebug_iter_next(struct ddebug_iter *iter) { if (iter->table == NULL) return NULL; - if (++iter->idx == iter->table->num_ddebugs) { + if (--iter->idx < 0) { /* iterate to next table */ - iter->idx = 0; if (list_is_last(&iter->table->link, &ddebug_tables)) { iter->table = NULL; return NULL; } iter->table = list_entry(iter->table->link.next, struct ddebug_table, link); + iter->idx = iter->table->num_ddebugs; + --iter->idx; } return &iter->table->ddebugs[iter->idx]; } @@ -876,6 +1102,20 @@ static void *ddebug_proc_next(struct seq_file *m, void *p, loff_t *pos) return dp; } +#define class_in_range(class_id, map) \ + (class_id >= map->base && class_id < map->base + map->length) + +static const char *ddebug_class_name(struct ddebug_iter *iter, struct _ddebug *dp) +{ + struct ddebug_class_map *map; + + list_for_each_entry(map, &iter->table->maps, link) + if (class_in_range(dp->class_id, map)) + return map->class_names[dp->class_id - map->base]; + + return NULL; +} + /* * Seq_ops show method. Called several times within a read() * call from userspace, with ddebug_lock held. Formats the @@ -887,6 +1127,7 @@ static int ddebug_proc_show(struct seq_file *m, void *p) struct ddebug_iter *iter = m->private; struct _ddebug *dp = p; struct flagsbuf flags; + char const *class; if (p == SEQ_START_TOKEN) { seq_puts(m, @@ -898,8 +1139,17 @@ static int ddebug_proc_show(struct seq_file *m, void *p) trim_prefix(dp->filename), dp->lineno, iter->table->mod_name, dp->function, ddebug_describe_flags(dp->flags, &flags)); - seq_escape(m, dp->format, "\t\r\n\""); - seq_puts(m, "\"\n"); + seq_escape_str(m, dp->format, ESCAPE_SPACE, "\t\r\n\""); + seq_puts(m, "\""); + + if (dp->class_id != _DPRINTK_CLASS_DFLT) { + class = ddebug_class_name(iter, dp); + if (class) + seq_printf(m, " class:%s", class); + else + seq_printf(m, " class unknown, _id:%d", dp->class_id); + } + seq_puts(m, "\n"); return 0; } @@ -943,18 +1193,50 @@ static const struct proc_ops proc_fops = { .proc_write = ddebug_proc_write }; +static void ddebug_attach_module_classes(struct ddebug_table *dt, + struct ddebug_class_map *classes, + int num_classes) +{ + struct ddebug_class_map *cm; + int i, j, ct = 0; + + for (cm = classes, i = 0; i < num_classes; i++, cm++) { + + if (!strcmp(cm->mod_name, dt->mod_name)) { + + v2pr_info("class[%d]: module:%s base:%d len:%d ty:%d\n", i, + cm->mod_name, cm->base, cm->length, cm->map_type); + + for (j = 0; j < cm->length; j++) + v3pr_info(" %d: %d %s\n", j + cm->base, j, + cm->class_names[j]); + + list_add(&cm->link, &dt->maps); + ct++; + } + } + if (ct) + vpr_info("module:%s attached %d classes\n", dt->mod_name, ct); +} + /* * Allocate a new ddebug_table for the given module * and add it to the global list. */ -int ddebug_add_module(struct _ddebug *tab, unsigned int n, - const char *name) +static int __ddebug_add_module(struct _ddebug_info *di, unsigned int base, + const char *modname) { struct ddebug_table *dt; + v3pr_info("add-module: %s.%d sites\n", modname, di->num_descs); + if (!di->num_descs) { + v3pr_info(" skip %s\n", modname); + return 0; + } + dt = kzalloc(sizeof(*dt), GFP_KERNEL); if (dt == NULL) { - pr_err("error adding module: %s\n", name); + pr_err("error adding module: %s\n", modname); return -ENOMEM; } /* @@ -963,18 +1245,29 @@ int ddebug_add_module(struct _ddebug *tab, unsigned int n, * member of struct module, which lives at least as long as * this struct ddebug_table. */ - dt->mod_name = name; - dt->num_ddebugs = n; - dt->ddebugs = tab; + dt->mod_name = modname; + dt->ddebugs = di->descs; + dt->num_ddebugs = di->num_descs; + + INIT_LIST_HEAD(&dt->link); + INIT_LIST_HEAD(&dt->maps); + + if (di->classes && di->num_classes) + ddebug_attach_module_classes(dt, di->classes, di->num_classes); mutex_lock(&ddebug_lock); - list_add(&dt->link, &ddebug_tables); + list_add_tail(&dt->link, &ddebug_tables); mutex_unlock(&ddebug_lock); - vpr_info("%3u debug prints in module %s\n", n, dt->mod_name); + vpr_info("%3u debug prints in module %s\n", di->num_descs, modname); return 0; } +int ddebug_add_module(struct _ddebug_info *di, const char *modname) +{ + return __ddebug_add_module(di, 0, modname); +} + /* helper for ddebug_dyndbg_(boot|module)_param_cb */ static int ddebug_dyndbg_param_cb(char *param, char *val, const char *modname, int on_err) @@ -1083,11 +1376,17 @@ static int __init dynamic_debug_init_control(void) static int __init dynamic_debug_init(void) { - struct _ddebug *iter, *iter_start; - const char *modname = NULL; + struct _ddebug *iter, *iter_mod_start; + int ret, i, mod_sites, mod_ct; + const char *modname; char *cmdline; - int ret = 0; - int n = 0, entries = 0, modct = 0; + + struct _ddebug_info di = { + .descs = __start___dyndbg, + .classes = __start___dyndbg_classes, + .num_descs = __stop___dyndbg - __start___dyndbg, + .num_classes = __stop___dyndbg_classes - __start___dyndbg_classes, + }; if (&__start___dyndbg == &__stop___dyndbg) { if (IS_ENABLED(CONFIG_DYNAMIC_DEBUG)) { @@ -1098,30 +1397,39 @@ static int __init dynamic_debug_init(void) ddebug_init_success = 1; return 0; } - iter = __start___dyndbg; + + iter = iter_mod_start = __start___dyndbg; modname = iter->modname; - iter_start = iter; - for (; iter < __stop___dyndbg; iter++) { - entries++; + i = mod_sites = mod_ct = 0; + + for (; iter < __stop___dyndbg; iter++, i++, mod_sites++) { + if (strcmp(modname, iter->modname)) { - modct++; - ret = ddebug_add_module(iter_start, n, modname); + mod_ct++; + di.num_descs = mod_sites; + di.descs = iter_mod_start; + ret = __ddebug_add_module(&di, i - mod_sites, modname); if (ret) goto out_err; - n = 0; + + mod_sites = 0; modname = iter->modname; - iter_start = iter; + iter_mod_start = iter; } - n++; } - ret = ddebug_add_module(iter_start, n, modname); + di.num_descs = mod_sites; + di.descs = iter_mod_start; + ret = __ddebug_add_module(&di, i - mod_sites, modname); if (ret) goto out_err; ddebug_init_success = 1; vpr_info("%d prdebugs in %d modules, %d KiB in ddebug tables, %d kiB in __dyndbg section\n", - entries, modct, (int)((modct * sizeof(struct ddebug_table)) >> 10), - (int)((entries * sizeof(struct _ddebug)) >> 10)); + i, mod_ct, (int)((mod_ct * sizeof(struct ddebug_table)) >> 10), + (int)((i * sizeof(struct _ddebug)) >> 10)); + + if (di.num_classes) + v2pr_info(" %d builtin ddebug class-maps\n", di.num_classes); /* now that ddebug tables are loaded, process all boot args * again to find and activate queries given in dyndbg params. diff --git a/lib/test_dynamic_debug.c b/lib/test_dynamic_debug.c new file mode 100644 index 000000000000..8dd250ad022b --- /dev/null +++ b/lib/test_dynamic_debug.c @@ -0,0 +1,165 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Kernel module for testing dynamic_debug + * + * Authors: + * Jim Cromie <jim.cromie@gmail.com> + */ + +#define pr_fmt(fmt) "test_dd: " fmt + +#include <linux/module.h> + +/* run tests by reading or writing sysfs node: do_prints */ + +static void do_prints(void); /* device under test */ +static int param_set_do_prints(const char *instr, const struct kernel_param *kp) +{ + do_prints(); + return 0; +} +static int param_get_do_prints(char *buffer, const struct kernel_param *kp) +{ + do_prints(); + return scnprintf(buffer, PAGE_SIZE, "did do_prints\n"); +} +static const struct kernel_param_ops param_ops_do_prints = { + .set = param_set_do_prints, + .get = param_get_do_prints, +}; +module_param_cb(do_prints, ¶m_ops_do_prints, NULL, 0600); + +/* + * Using the CLASSMAP api: + * - classmaps must have corresponding enum + * - enum symbols must match/correlate with class-name strings in the map. + * - base must equal enum's 1st value + * - multiple maps must set their base to share the 0-30 class_id space !! + * (build-bug-on tips welcome) + * Additionally, here: + * - tie together sysname, mapname, bitsname, flagsname + */ +#define DD_SYS_WRAP(_model, _flags) \ + static unsigned long bits_##_model; \ + static struct ddebug_class_param _flags##_model = { \ + .bits = &bits_##_model, \ + .flags = #_flags, \ + .map = &map_##_model, \ + }; \ + module_param_cb(_flags##_##_model, ¶m_ops_dyndbg_classes, &_flags##_model, 0600) + +/* numeric input, independent bits */ +enum cat_disjoint_bits { + D2_CORE = 0, + D2_DRIVER, + D2_KMS, + D2_PRIME, + D2_ATOMIC, + D2_VBL, + D2_STATE, + D2_LEASE, + D2_DP, + D2_DRMRES }; +DECLARE_DYNDBG_CLASSMAP(map_disjoint_bits, DD_CLASS_TYPE_DISJOINT_BITS, 0, + "D2_CORE", + "D2_DRIVER", + "D2_KMS", + "D2_PRIME", + "D2_ATOMIC", + "D2_VBL", + "D2_STATE", + "D2_LEASE", + "D2_DP", + "D2_DRMRES"); +DD_SYS_WRAP(disjoint_bits, p); +DD_SYS_WRAP(disjoint_bits, T); + +/* symbolic input, independent bits */ +enum cat_disjoint_names { LOW = 11, MID, HI }; +DECLARE_DYNDBG_CLASSMAP(map_disjoint_names, DD_CLASS_TYPE_DISJOINT_NAMES, 10, + "LOW", "MID", "HI"); +DD_SYS_WRAP(disjoint_names, p); +DD_SYS_WRAP(disjoint_names, T); + +/* numeric verbosity, V2 > V1 related */ +enum cat_level_num { V0 = 14, V1, V2, V3, V4, V5, V6, V7 }; +DECLARE_DYNDBG_CLASSMAP(map_level_num, DD_CLASS_TYPE_LEVEL_NUM, 14, + "V0", "V1", "V2", "V3", "V4", "V5", "V6", "V7"); +DD_SYS_WRAP(level_num, p); +DD_SYS_WRAP(level_num, T); + +/* symbolic verbosity */ +enum cat_level_names { L0 = 22, L1, L2, L3, L4, L5, L6, L7 }; +DECLARE_DYNDBG_CLASSMAP(map_level_names, DD_CLASS_TYPE_LEVEL_NAMES, 22, + "L0", "L1", "L2", "L3", "L4", "L5", "L6", "L7"); +DD_SYS_WRAP(level_names, p); +DD_SYS_WRAP(level_names, T); + +/* stand-in for all pr_debug etc */ +#define prdbg(SYM) __pr_debug_cls(SYM, #SYM " msg\n") + +static void do_cats(void) +{ + pr_debug("doing categories\n"); + + prdbg(LOW); + prdbg(MID); + prdbg(HI); + + prdbg(D2_CORE); + prdbg(D2_DRIVER); + prdbg(D2_KMS); + prdbg(D2_PRIME); + prdbg(D2_ATOMIC); + prdbg(D2_VBL); + prdbg(D2_STATE); + prdbg(D2_LEASE); + prdbg(D2_DP); + prdbg(D2_DRMRES); +} + +static void do_levels(void) +{ + pr_debug("doing levels\n"); + + prdbg(V1); + prdbg(V2); + prdbg(V3); + prdbg(V4); + prdbg(V5); + prdbg(V6); + prdbg(V7); + + prdbg(L1); + prdbg(L2); + prdbg(L3); + prdbg(L4); + prdbg(L5); + prdbg(L6); + prdbg(L7); +} + +static void do_prints(void) +{ + do_cats(); + do_levels(); +} + +static int __init test_dynamic_debug_init(void) +{ + pr_debug("init start\n"); + do_prints(); + pr_debug("init done\n"); + return 0; +} + +static void __exit test_dynamic_debug_exit(void) +{ + pr_debug("exited\n"); +} + +module_init(test_dynamic_debug_init); +module_exit(test_dynamic_debug_exit); + +MODULE_AUTHOR("Jim Cromie <jim.cromie@gmail.com>"); +MODULE_LICENSE("GPL"); |