From 7162431dcf72032835d369c8d7b51311df407938 Mon Sep 17 00:00:00 2001 From: Miroslav Benes Date: Wed, 16 Oct 2019 13:33:13 +0200 Subject: ftrace: Introduce PERMANENT ftrace_ops flag Livepatch uses ftrace for redirection to new patched functions. It means that if ftrace is disabled, all live patched functions are disabled as well. Toggling global 'ftrace_enabled' sysctl thus affect it directly. It is not a problem per se, because only administrator can set sysctl values, but it still may be surprising. Introduce PERMANENT ftrace_ops flag to amend this. If the FTRACE_OPS_FL_PERMANENT is set on any ftrace ops, the tracing cannot be disabled by disabling ftrace_enabled. Equally, a callback with the flag set cannot be registered if ftrace_enabled is disabled. Link: http://lkml.kernel.org/r/20191016113316.13415-2-mbenes@suse.cz Reviewed-by: Petr Mladek Reviewed-by: Kamalesh Babulal Signed-off-by: Miroslav Benes Signed-off-by: Steven Rostedt (VMware) --- include/linux/ftrace.h | 3 +++ 1 file changed, 3 insertions(+) (limited to 'include/linux') diff --git a/include/linux/ftrace.h b/include/linux/ftrace.h index 8a8cb3c401b2..8385cafe4f9f 100644 --- a/include/linux/ftrace.h +++ b/include/linux/ftrace.h @@ -142,6 +142,8 @@ ftrace_func_t ftrace_ops_get_func(struct ftrace_ops *ops); * PID - Is affected by set_ftrace_pid (allows filtering on those pids) * RCU - Set when the ops can only be called when RCU is watching. * TRACE_ARRAY - The ops->private points to a trace_array descriptor. + * PERMANENT - Set when the ops is permanent and should not be affected by + * ftrace_enabled. */ enum { FTRACE_OPS_FL_ENABLED = 1 << 0, @@ -160,6 +162,7 @@ enum { FTRACE_OPS_FL_PID = 1 << 13, FTRACE_OPS_FL_RCU = 1 << 14, FTRACE_OPS_FL_TRACE_ARRAY = 1 << 15, + FTRACE_OPS_FL_PERMANENT = 1 << 16, }; #ifdef CONFIG_DYNAMIC_FTRACE -- cgit v1.2.3 From 763e34e74bb7d5c316015e2e39fcc8520bfd071c Mon Sep 17 00:00:00 2001 From: "Steven Rostedt (VMware)" Date: Fri, 8 Nov 2019 13:07:06 -0500 Subject: ftrace: Add register_ftrace_direct() Add the start of the functionality to allow other trampolines to use the ftrace mcount/fentry/nop location. This adds two new functions: register_ftrace_direct() and unregister_ftrace_direct() Both take two parameters: the first is the instruction address of where the mcount/fentry/nop exists, and the second is the trampoline to have that location called. This will handle cases where ftrace is already used on that same location, and will make it still work, where the registered direct called trampoline will get called after all the registered ftrace callers are handled. Currently, it will not allow for IP_MODIFY functions to be called at the same locations, which include some kprobes and live kernel patching. At this point, no architecture supports this. This is only the start of implementing the framework. Signed-off-by: Steven Rostedt (VMware) --- include/linux/ftrace.h | 36 ++++++++++++++++++++++++++++++++++-- 1 file changed, 34 insertions(+), 2 deletions(-) (limited to 'include/linux') diff --git a/include/linux/ftrace.h b/include/linux/ftrace.h index 8385cafe4f9f..efe3e521aff4 100644 --- a/include/linux/ftrace.h +++ b/include/linux/ftrace.h @@ -144,6 +144,8 @@ ftrace_func_t ftrace_ops_get_func(struct ftrace_ops *ops); * TRACE_ARRAY - The ops->private points to a trace_array descriptor. * PERMANENT - Set when the ops is permanent and should not be affected by * ftrace_enabled. + * DIRECT - Used by the direct ftrace_ops helper for direct functions + * (internal ftrace only, should not be used by others) */ enum { FTRACE_OPS_FL_ENABLED = 1 << 0, @@ -163,6 +165,7 @@ enum { FTRACE_OPS_FL_RCU = 1 << 14, FTRACE_OPS_FL_TRACE_ARRAY = 1 << 15, FTRACE_OPS_FL_PERMANENT = 1 << 16, + FTRACE_OPS_FL_DIRECT = 1 << 17, }; #ifdef CONFIG_DYNAMIC_FTRACE @@ -242,6 +245,32 @@ static inline void ftrace_free_init_mem(void) { } static inline void ftrace_free_mem(struct module *mod, void *start, void *end) { } #endif /* CONFIG_FUNCTION_TRACER */ +#ifdef CONFIG_DYNAMIC_FTRACE_WITH_DIRECT_CALLS +int register_ftrace_direct(unsigned long ip, unsigned long addr); +int unregister_ftrace_direct(unsigned long ip, unsigned long addr); +#else +static inline int register_ftrace_direct(unsigned long ip, unsigned long addr) +{ + return -ENODEV; +} +static inline int unregister_ftrace_direct(unsigned long ip, unsigned long addr) +{ + return -ENODEV; +} +#endif /* CONFIG_DYNAMIC_FTRACE_WITH_DIRECT_CALLS */ + +#ifndef CONFIG_HAVE_DYNAMIC_FTRACE_WITH_DIRECT_CALLS +/* + * This must be implemented by the architecture. + * It is the way the ftrace direct_ops helper, when called + * via ftrace (because there's other callbacks besides the + * direct call), can inform the architecture's trampoline that this + * routine has a direct caller, and what the caller is. + */ +static inline void arch_ftrace_set_direct_caller(struct pt_regs *regs, + unsigned long addr) { } +#endif /* CONFIG_HAVE_DYNAMIC_FTRACE_WITH_DIRECT_CALLS */ + #ifdef CONFIG_STACK_TRACER extern int stack_tracer_enabled; @@ -333,6 +362,7 @@ bool is_ftrace_trampoline(unsigned long addr); * REGS_EN - the function is set up to save regs. * IPMODIFY - the record allows for the IP address to be changed. * DISABLED - the record is not ready to be touched yet + * DIRECT - there is a direct function to call * * When a new ftrace_ops is registered and wants a function to save * pt_regs, the rec->flag REGS is set. When the function has been @@ -348,10 +378,12 @@ enum { FTRACE_FL_TRAMP_EN = (1UL << 27), FTRACE_FL_IPMODIFY = (1UL << 26), FTRACE_FL_DISABLED = (1UL << 25), + FTRACE_FL_DIRECT = (1UL << 24), + FTRACE_FL_DIRECT_EN = (1UL << 23), }; -#define FTRACE_REF_MAX_SHIFT 25 -#define FTRACE_FL_BITS 7 +#define FTRACE_REF_MAX_SHIFT 23 +#define FTRACE_FL_BITS 9 #define FTRACE_FL_MASKED_BITS ((1UL << FTRACE_FL_BITS) - 1) #define FTRACE_FL_MASK (FTRACE_FL_MASKED_BITS << FTRACE_REF_MAX_SHIFT) #define FTRACE_REF_MAX ((1UL << FTRACE_REF_MAX_SHIFT) - 1) -- cgit v1.2.3 From 013bf0da0474816f57739daa006c8564ad7396a3 Mon Sep 17 00:00:00 2001 From: "Steven Rostedt (VMware)" Date: Fri, 8 Nov 2019 13:11:27 -0500 Subject: ftrace: Add ftrace_find_direct_func() As function_graph tracer modifies the return address to insert a trampoline to trace the return of a function, it must be aware of a direct caller, as when it gets called, the function's return address may not be at on the stack where it expects. It may have to see if that return address points to the a direct caller and adjust if it is. Signed-off-by: Steven Rostedt (VMware) --- include/linux/ftrace.h | 6 ++++++ 1 file changed, 6 insertions(+) (limited to 'include/linux') diff --git a/include/linux/ftrace.h b/include/linux/ftrace.h index efe3e521aff4..8b37b8105398 100644 --- a/include/linux/ftrace.h +++ b/include/linux/ftrace.h @@ -51,6 +51,7 @@ static inline void early_trace_init(void) { } struct module; struct ftrace_hash; +struct ftrace_direct_func; #if defined(CONFIG_FUNCTION_TRACER) && defined(CONFIG_MODULES) && \ defined(CONFIG_DYNAMIC_FTRACE) @@ -248,6 +249,7 @@ static inline void ftrace_free_mem(struct module *mod, void *start, void *end) { #ifdef CONFIG_DYNAMIC_FTRACE_WITH_DIRECT_CALLS int register_ftrace_direct(unsigned long ip, unsigned long addr); int unregister_ftrace_direct(unsigned long ip, unsigned long addr); +struct ftrace_direct_func *ftrace_find_direct_func(unsigned long addr); #else static inline int register_ftrace_direct(unsigned long ip, unsigned long addr) { @@ -257,6 +259,10 @@ static inline int unregister_ftrace_direct(unsigned long ip, unsigned long addr) { return -ENODEV; } +static inline struct ftrace_direct_func *ftrace_find_direct_func(unsigned long addr) +{ + return NULL; +} #endif /* CONFIG_DYNAMIC_FTRACE_WITH_DIRECT_CALLS */ #ifndef CONFIG_HAVE_DYNAMIC_FTRACE_WITH_DIRECT_CALLS -- cgit v1.2.3 From 562955fe6a558b9ef98ad87c470314946338cb2f Mon Sep 17 00:00:00 2001 From: "Steven Rostedt (VMware)" Date: Fri, 8 Nov 2019 13:11:39 -0500 Subject: ftrace/x86: Add register_ftrace_direct() for custom trampolines Enable x86 to allow for register_ftrace_direct(), where a custom trampoline may be called directly from an ftrace mcount/fentry location. Signed-off-by: Steven Rostedt (VMware) --- include/linux/ftrace.h | 6 ++++++ 1 file changed, 6 insertions(+) (limited to 'include/linux') diff --git a/include/linux/ftrace.h b/include/linux/ftrace.h index 8b37b8105398..2bc7bd6b8387 100644 --- a/include/linux/ftrace.h +++ b/include/linux/ftrace.h @@ -272,6 +272,12 @@ static inline struct ftrace_direct_func *ftrace_find_direct_func(unsigned long a * via ftrace (because there's other callbacks besides the * direct call), can inform the architecture's trampoline that this * routine has a direct caller, and what the caller is. + * + * For example, in x86, it returns the direct caller + * callback function via the regs->orig_ax parameter. + * Then in the ftrace trampoline, if this is set, it makes + * the return from the trampoline jump to the direct caller + * instead of going back to the function it just traced. */ static inline void arch_ftrace_set_direct_caller(struct pt_regs *regs, unsigned long addr) { } -- cgit v1.2.3 From a3ad1a7e39689005cb04a4f2adb82f9d55b4724f Mon Sep 17 00:00:00 2001 From: "Steven Rostedt (VMware)" Date: Fri, 8 Nov 2019 13:12:57 -0500 Subject: ftrace/x86: Add a counter to test function_graph with direct As testing for direct calls from the function graph tracer adds a little overhead (which is a lot when tracing every function), add a counter that can be used to test if function_graph tracer needs to test for a direct caller or not. It would have been nicer if we could use a static branch, but the static branch logic fails when used within the function graph tracer trampoline. Signed-off-by: Steven Rostedt (VMware) --- include/linux/ftrace.h | 2 ++ 1 file changed, 2 insertions(+) (limited to 'include/linux') diff --git a/include/linux/ftrace.h b/include/linux/ftrace.h index 2bc7bd6b8387..55647e185141 100644 --- a/include/linux/ftrace.h +++ b/include/linux/ftrace.h @@ -247,10 +247,12 @@ static inline void ftrace_free_mem(struct module *mod, void *start, void *end) { #endif /* CONFIG_FUNCTION_TRACER */ #ifdef CONFIG_DYNAMIC_FTRACE_WITH_DIRECT_CALLS +extern int ftrace_direct_func_count; int register_ftrace_direct(unsigned long ip, unsigned long addr); int unregister_ftrace_direct(unsigned long ip, unsigned long addr); struct ftrace_direct_func *ftrace_find_direct_func(unsigned long addr); #else +# define ftrace_direct_func_count 0 static inline int register_ftrace_direct(unsigned long ip, unsigned long addr) { return -ENODEV; -- cgit v1.2.3 From 2d6425af61166e026e7476db64f70f1266127b1d Mon Sep 17 00:00:00 2001 From: Divya Indi Date: Wed, 14 Aug 2019 10:55:23 -0700 Subject: tracing: Declare newly exported APIs in include/linux/trace.h Declare the newly introduced and exported APIs in the header file - include/linux/trace.h. Moving previous declarations from kernel/trace/trace.h to include/linux/trace.h. Link: http://lkml.kernel.org/r/1565805327-579-2-git-send-email-divya.indi@oracle.com Signed-off-by: Divya Indi Signed-off-by: Steven Rostedt (VMware) --- include/linux/trace.h | 7 +++++++ 1 file changed, 7 insertions(+) (limited to 'include/linux') diff --git a/include/linux/trace.h b/include/linux/trace.h index b95ffb2188ab..24fcf07812ae 100644 --- a/include/linux/trace.h +++ b/include/linux/trace.h @@ -24,6 +24,13 @@ struct trace_export { int register_ftrace_export(struct trace_export *export); int unregister_ftrace_export(struct trace_export *export); +struct trace_array; + +void trace_printk_init_buffers(void); +int trace_array_printk(struct trace_array *tr, unsigned long ip, + const char *fmt, ...); +struct trace_array *trace_array_create(const char *name); +int trace_array_destroy(struct trace_array *tr); #endif /* CONFIG_TRACING */ #endif /* _LINUX_TRACE_H */ -- cgit v1.2.3 From 52ae533b8a18e7ca868e7ac5953ad7258210f320 Mon Sep 17 00:00:00 2001 From: Andy Shevchenko Date: Mon, 7 Oct 2019 16:56:54 +0300 Subject: lib/sort: Move swap, cmp and cmp_r function types for wider use The function types for swap, cmp and cmp_r functions are already being in use by modules. Move them to types.h that everybody in kernel will be able to use generic types instead of custom ones. This adds more sense to the comment in bsearch() later on. Link: http://lkml.kernel.org/r/20191007135656.37734-1-andriy.shevchenko@linux.intel.com Signed-off-by: Andy Shevchenko Signed-off-by: Steven Rostedt (VMware) --- include/linux/sort.h | 8 ++++---- include/linux/types.h | 5 +++++ 2 files changed, 9 insertions(+), 4 deletions(-) (limited to 'include/linux') diff --git a/include/linux/sort.h b/include/linux/sort.h index 61b96d0ebc44..b5898725fe9d 100644 --- a/include/linux/sort.h +++ b/include/linux/sort.h @@ -5,12 +5,12 @@ #include void sort_r(void *base, size_t num, size_t size, - int (*cmp)(const void *, const void *, const void *), - void (*swap)(void *, void *, int), + cmp_r_func_t cmp_func, + swap_func_t swap_func, const void *priv); void sort(void *base, size_t num, size_t size, - int (*cmp)(const void *, const void *), - void (*swap)(void *, void *, int)); + cmp_func_t cmp_func, + swap_func_t swap_func); #endif diff --git a/include/linux/types.h b/include/linux/types.h index 05030f608be3..85c0e7b18153 100644 --- a/include/linux/types.h +++ b/include/linux/types.h @@ -225,5 +225,10 @@ struct callback_head { typedef void (*rcu_callback_t)(struct rcu_head *head); typedef void (*call_rcu_func_t)(struct rcu_head *head, rcu_callback_t func); +typedef void (*swap_func_t)(void *a, void *b, int size); + +typedef int (*cmp_r_func_t)(const void *a, const void *b, const void *priv); +typedef int (*cmp_func_t)(const void *a, const void *b); + #endif /* __ASSEMBLY__ */ #endif /* _LINUX_TYPES_H */ -- cgit v1.2.3 From e8877ec5dbba6f39d25ca3a81716c23b1760f2ee Mon Sep 17 00:00:00 2001 From: Andy Shevchenko Date: Mon, 7 Oct 2019 16:56:55 +0300 Subject: lib/bsearch: Use generic type for comparator function Comparator function type, cmp_func_t, is defined in the types.h, use it in bsearch() and, thus, add more sense to the corresponding comment in the code. Link: http://lkml.kernel.org/r/20191007135656.37734-2-andriy.shevchenko@linux.intel.com Signed-off-by: Andy Shevchenko Signed-off-by: Steven Rostedt (VMware) --- include/linux/bsearch.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'include/linux') diff --git a/include/linux/bsearch.h b/include/linux/bsearch.h index 62b1eb348858..8ed53d7524ea 100644 --- a/include/linux/bsearch.h +++ b/include/linux/bsearch.h @@ -5,6 +5,6 @@ #include void *bsearch(const void *key, const void *base, size_t num, size_t size, - int (*cmp)(const void *key, const void *elt)); + cmp_func_t cmp); #endif /* _LINUX_BSEARCH_H */ -- cgit v1.2.3 From 353cade3149c27b53260932ee3ff1ebde405976d Mon Sep 17 00:00:00 2001 From: Piotr Maziarz Date: Thu, 7 Nov 2019 13:45:37 +0100 Subject: seq_buf: Add printing formatted hex dumps Provided function is an analogue of print_hex_dump(). Implementing this function in seq_buf allows using for multiple purposes (e.g. for tracing) and therefore prevents from code duplication in every layer that uses seq_buf. print_hex_dump() is an essential part of logging data to dmesg. Adding similar capability for other purposes is beneficial to all users. Example usage: seq_buf_hex_dump(seq, "", DUMP_PREFIX_OFFSET, 16, 4, buf, ARRAY_SIZE(buf), true); Example output: 00000000: 00000000 ffffff10 ffffff32 ffff3210 ........2....2.. 00000010: ffff3210 83d00437 c0700000 00000000 .2..7.....p..... 00000020: 02010004 0000000f 0000000f 00004002 .............@.. 00000030: 00000fff 00000000 ........ Link: http://lkml.kernel.org/r/1573130738-29390-1-git-send-email-piotrx.maziarz@linux.intel.com Signed-off-by: Piotr Maziarz Signed-off-by: Cezary Rojewski Signed-off-by: Steven Rostedt (VMware) --- include/linux/seq_buf.h | 3 +++ 1 file changed, 3 insertions(+) (limited to 'include/linux') diff --git a/include/linux/seq_buf.h b/include/linux/seq_buf.h index aa5deb041c25..fb0205d87d3c 100644 --- a/include/linux/seq_buf.h +++ b/include/linux/seq_buf.h @@ -125,6 +125,9 @@ extern int seq_buf_putmem(struct seq_buf *s, const void *mem, unsigned int len); extern int seq_buf_putmem_hex(struct seq_buf *s, const void *mem, unsigned int len); extern int seq_buf_path(struct seq_buf *s, const struct path *path, const char *esc); +extern int seq_buf_hex_dump(struct seq_buf *s, const char *prefix_str, + int prefix_type, int rowsize, int groupsize, + const void *buf, size_t len, bool ascii); #ifdef CONFIG_BINARY_PRINTF extern int -- cgit v1.2.3 From ef56e047b2bd4dabb801fd073dfcab5f40de5f78 Mon Sep 17 00:00:00 2001 From: Piotr Maziarz Date: Thu, 7 Nov 2019 13:45:38 +0100 Subject: tracing: Use seq_buf_hex_dump() to dump buffers Without this, buffers can be printed with __print_array macro that has no formatting options and can be hard to read. The other way is to mimic formatting capability with multiple calls of trace event with one call per row which gives performance impact and different timestamp in each row. Link: http://lkml.kernel.org/r/1573130738-29390-2-git-send-email-piotrx.maziarz@linux.intel.com Signed-off-by: Piotr Maziarz Signed-off-by: Cezary Rojewski Signed-off-by: Steven Rostedt (VMware) --- include/linux/trace_events.h | 5 +++++ include/linux/trace_seq.h | 4 ++++ 2 files changed, 9 insertions(+) (limited to 'include/linux') diff --git a/include/linux/trace_events.h b/include/linux/trace_events.h index 30a8cdcfd4a4..60a41b7069dd 100644 --- a/include/linux/trace_events.h +++ b/include/linux/trace_events.h @@ -45,6 +45,11 @@ const char *trace_print_array_seq(struct trace_seq *p, const void *buf, int count, size_t el_size); +const char * +trace_print_hex_dump_seq(struct trace_seq *p, const char *prefix_str, + int prefix_type, int rowsize, int groupsize, + const void *buf, size_t len, bool ascii); + struct trace_iterator; struct trace_event; diff --git a/include/linux/trace_seq.h b/include/linux/trace_seq.h index 6609b39a7232..6c30508fca19 100644 --- a/include/linux/trace_seq.h +++ b/include/linux/trace_seq.h @@ -92,6 +92,10 @@ extern int trace_seq_path(struct trace_seq *s, const struct path *path); extern void trace_seq_bitmask(struct trace_seq *s, const unsigned long *maskp, int nmaskbits); +extern int trace_seq_hex_dump(struct trace_seq *s, const char *prefix_str, + int prefix_type, int rowsize, int groupsize, + const void *buf, size_t len, bool ascii); + #else /* CONFIG_TRACING */ static inline void trace_seq_printf(struct trace_seq *s, const char *fmt, ...) { -- cgit v1.2.3 From 0567d6809182df53da03636fad36c507c5cf07a5 Mon Sep 17 00:00:00 2001 From: "Steven Rostedt (VMware)" Date: Thu, 14 Nov 2019 14:39:35 -0500 Subject: ftrace: Add modify_ftrace_direct() Add a new function modify_ftrace_direct() that will allow a user to update an existing direct caller to a new trampoline, without missing hits due to unregistering one and then adding another. Link: https://lore.kernel.org/r/20191109022907.6zzo6orhxpt5n2sv@ast-mbp.dhcp.thefacebook.com Suggested-by: Alexei Starovoitov Signed-off-by: Steven Rostedt (VMware) --- include/linux/ftrace.h | 6 ++++++ 1 file changed, 6 insertions(+) (limited to 'include/linux') diff --git a/include/linux/ftrace.h b/include/linux/ftrace.h index 55647e185141..73eb2e93593f 100644 --- a/include/linux/ftrace.h +++ b/include/linux/ftrace.h @@ -250,6 +250,7 @@ static inline void ftrace_free_mem(struct module *mod, void *start, void *end) { extern int ftrace_direct_func_count; int register_ftrace_direct(unsigned long ip, unsigned long addr); int unregister_ftrace_direct(unsigned long ip, unsigned long addr); +int modify_ftrace_direct(unsigned long ip, unsigned long old_addr, unsigned long new_addr); struct ftrace_direct_func *ftrace_find_direct_func(unsigned long addr); #else # define ftrace_direct_func_count 0 @@ -261,6 +262,11 @@ static inline int unregister_ftrace_direct(unsigned long ip, unsigned long addr) { return -ENODEV; } +static inline int modify_ftrace_direct(unsigned long ip, + unsigned long old_addr, unsigned long new_addr) +{ + return -ENODEV; +} static inline struct ftrace_direct_func *ftrace_find_direct_func(unsigned long addr) { return NULL; -- cgit v1.2.3 From ea806eb3eab35528b578a061b2c4b28f0f92c465 Mon Sep 17 00:00:00 2001 From: "Steven Rostedt (VMware)" Date: Sun, 17 Nov 2019 17:04:15 -0500 Subject: ftrace: Add a helper function to modify_ftrace_direct() to allow arch optimization If a direct ftrace callback is at a location that does not have any other ftrace helpers attached to it, it is possible to simply just change the text to call the new caller (if the architecture supports it). But this requires special architecture code. Currently, modify_ftrace_direct() uses a trick to add a stub ftrace callback to the location forcing it to call the ftrace iterator. Then it can change the direct helper to call the new function in C, and then remove the stub. Removing the stub will have the location now call the new location that the direct helper is using. The new helper function does the registering the stub trick, but is a weak function, allowing an architecture to override it to do something a bit more direct. Link: https://lore.kernel.org/r/20191115215125.mbqv7taqnx376yed@ast-mbp.dhcp.thefacebook.com Suggested-by: Alexei Starovoitov Signed-off-by: Steven Rostedt (VMware) --- include/linux/ftrace.h | 21 +++++++++++++++++++-- 1 file changed, 19 insertions(+), 2 deletions(-) (limited to 'include/linux') diff --git a/include/linux/ftrace.h b/include/linux/ftrace.h index 73eb2e93593f..dfaa37e1943d 100644 --- a/include/linux/ftrace.h +++ b/include/linux/ftrace.h @@ -246,12 +246,24 @@ static inline void ftrace_free_init_mem(void) { } static inline void ftrace_free_mem(struct module *mod, void *start, void *end) { } #endif /* CONFIG_FUNCTION_TRACER */ +struct ftrace_func_entry { + struct hlist_node hlist; + unsigned long ip; + unsigned long direct; /* for direct lookup only */ +}; + +struct dyn_ftrace; + #ifdef CONFIG_DYNAMIC_FTRACE_WITH_DIRECT_CALLS extern int ftrace_direct_func_count; int register_ftrace_direct(unsigned long ip, unsigned long addr); int unregister_ftrace_direct(unsigned long ip, unsigned long addr); int modify_ftrace_direct(unsigned long ip, unsigned long old_addr, unsigned long new_addr); struct ftrace_direct_func *ftrace_find_direct_func(unsigned long addr); +int ftrace_modify_direct_caller(struct ftrace_func_entry *entry, + struct dyn_ftrace *rec, + unsigned long old_addr, + unsigned long new_addr); #else # define ftrace_direct_func_count 0 static inline int register_ftrace_direct(unsigned long ip, unsigned long addr) @@ -271,6 +283,13 @@ static inline struct ftrace_direct_func *ftrace_find_direct_func(unsigned long a { return NULL; } +static inline int ftrace_modify_direct_caller(struct ftrace_func_entry *entry, + struct dyn_ftrace *rec, + unsigned long old_addr, + unsigned long new_addr) +{ + return -ENODEV; +} #endif /* CONFIG_DYNAMIC_FTRACE_WITH_DIRECT_CALLS */ #ifndef CONFIG_HAVE_DYNAMIC_FTRACE_WITH_DIRECT_CALLS @@ -343,8 +362,6 @@ static inline void stack_tracer_enable(void) { } int ftrace_arch_code_modify_prepare(void); int ftrace_arch_code_modify_post_process(void); -struct dyn_ftrace; - enum ftrace_bug_type { FTRACE_BUG_UNKNOWN, FTRACE_BUG_INIT, -- cgit v1.2.3 From eb01fedc3d539f9443082aa2384c5d1ca26ed5c1 Mon Sep 17 00:00:00 2001 From: Alexei Starovoitov Date: Wed, 20 Nov 2019 18:32:25 -0500 Subject: ftrace: Return ENOTSUPP when DYNAMIC_FTRACE_WITH_DIRECT_CALLS is not configured When CONFIG_DYNAMIC_FTRACE_WITH_DIRECT_CALLS is not set it's best to have the stub functions return ENOTSUPP instead of ENODEV, otherwise ENODEV is a valid error when ip is incorrect which is indistinguishable from ftrace not compiled in. Link: http://lkml.kernel.org/r/CAADnVQ+OzTikM9EhrfsC7NFsVYhATW1SVHxK64w3xn9qpk81pg@mail.gmail.com Signed-off-by: Alexei Starovoitov Signed-off-by: Steven Rostedt (VMware) --- include/linux/ftrace.h | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) (limited to 'include/linux') diff --git a/include/linux/ftrace.h b/include/linux/ftrace.h index dfaa37e1943d..af79b0f8cdc1 100644 --- a/include/linux/ftrace.h +++ b/include/linux/ftrace.h @@ -268,16 +268,16 @@ int ftrace_modify_direct_caller(struct ftrace_func_entry *entry, # define ftrace_direct_func_count 0 static inline int register_ftrace_direct(unsigned long ip, unsigned long addr) { - return -ENODEV; + return -ENOTSUPP; } static inline int unregister_ftrace_direct(unsigned long ip, unsigned long addr) { - return -ENODEV; + return -ENOTSUPP; } static inline int modify_ftrace_direct(unsigned long ip, unsigned long old_addr, unsigned long new_addr) { - return -ENODEV; + return -ENOTSUPP; } static inline struct ftrace_direct_func *ftrace_find_direct_func(unsigned long addr) { -- cgit v1.2.3 From b41db132821fdad9d80a177344a47468791fbe62 Mon Sep 17 00:00:00 2001 From: "Enrico Weigelt, metux IT consult" Date: Thu, 21 Nov 2019 14:38:15 +0100 Subject: ftrace: Use BIT() macro It's cleaner to use the BIT() macro instead of raw shift operation. Link: http://lkml.kernel.org/r/20191121133815.15040-1-info@metux.net Signed-off-by: Enrico Weigelt, metux IT consult [ Added BIT() for bits 16 and 17 ] Signed-off-by: Steven Rostedt (VMware) --- include/linux/ftrace.h | 36 ++++++++++++++++++------------------ 1 file changed, 18 insertions(+), 18 deletions(-) (limited to 'include/linux') diff --git a/include/linux/ftrace.h b/include/linux/ftrace.h index af79b0f8cdc1..232806d5689d 100644 --- a/include/linux/ftrace.h +++ b/include/linux/ftrace.h @@ -149,24 +149,24 @@ ftrace_func_t ftrace_ops_get_func(struct ftrace_ops *ops); * (internal ftrace only, should not be used by others) */ enum { - FTRACE_OPS_FL_ENABLED = 1 << 0, - FTRACE_OPS_FL_DYNAMIC = 1 << 1, - FTRACE_OPS_FL_SAVE_REGS = 1 << 2, - FTRACE_OPS_FL_SAVE_REGS_IF_SUPPORTED = 1 << 3, - FTRACE_OPS_FL_RECURSION_SAFE = 1 << 4, - FTRACE_OPS_FL_STUB = 1 << 5, - FTRACE_OPS_FL_INITIALIZED = 1 << 6, - FTRACE_OPS_FL_DELETED = 1 << 7, - FTRACE_OPS_FL_ADDING = 1 << 8, - FTRACE_OPS_FL_REMOVING = 1 << 9, - FTRACE_OPS_FL_MODIFYING = 1 << 10, - FTRACE_OPS_FL_ALLOC_TRAMP = 1 << 11, - FTRACE_OPS_FL_IPMODIFY = 1 << 12, - FTRACE_OPS_FL_PID = 1 << 13, - FTRACE_OPS_FL_RCU = 1 << 14, - FTRACE_OPS_FL_TRACE_ARRAY = 1 << 15, - FTRACE_OPS_FL_PERMANENT = 1 << 16, - FTRACE_OPS_FL_DIRECT = 1 << 17, + FTRACE_OPS_FL_ENABLED = BIT(0), + FTRACE_OPS_FL_DYNAMIC = BIT(1), + FTRACE_OPS_FL_SAVE_REGS = BIT(2), + FTRACE_OPS_FL_SAVE_REGS_IF_SUPPORTED = BIT(3), + FTRACE_OPS_FL_RECURSION_SAFE = BIT(4), + FTRACE_OPS_FL_STUB = BIT(5), + FTRACE_OPS_FL_INITIALIZED = BIT(6), + FTRACE_OPS_FL_DELETED = BIT(7), + FTRACE_OPS_FL_ADDING = BIT(8), + FTRACE_OPS_FL_REMOVING = BIT(9), + FTRACE_OPS_FL_MODIFYING = BIT(10), + FTRACE_OPS_FL_ALLOC_TRAMP = BIT(11), + FTRACE_OPS_FL_IPMODIFY = BIT(12), + FTRACE_OPS_FL_PID = BIT(13), + FTRACE_OPS_FL_RCU = BIT(14), + FTRACE_OPS_FL_TRACE_ARRAY = BIT(15), + FTRACE_OPS_FL_PERMANENT = BIT(16), + FTRACE_OPS_FL_DIRECT = BIT(17), }; #ifdef CONFIG_DYNAMIC_FTRACE -- cgit v1.2.3 From 28879787147358e8ffcae397f11748de3dd26577 Mon Sep 17 00:00:00 2001 From: Divya Indi Date: Wed, 20 Nov 2019 11:08:38 -0800 Subject: tracing: Adding new functions for kernel access to Ftrace instances Adding 2 new functions - 1) struct trace_array *trace_array_get_by_name(const char *name); Return pointer to a trace array with given name. If it does not exist, create and return pointer to the new trace array. 2) int trace_array_set_clr_event(struct trace_array *tr, const char *system ,const char *event, bool enable); Enable/Disable events to this trace array. Additionally, - To handle reference counters, export trace_array_put() - Due to introduction of the above 2 new functions, we no longer need to export - ftrace_set_clr_event & trace_array_create APIs. Link: http://lkml.kernel.org/r/1574276919-11119-2-git-send-email-divya.indi@oracle.com Signed-off-by: Divya Indi Reviewed-by: Aruna Ramakrishna Signed-off-by: Steven Rostedt (VMware) --- include/linux/trace.h | 3 ++- include/linux/trace_events.h | 3 ++- 2 files changed, 4 insertions(+), 2 deletions(-) (limited to 'include/linux') diff --git a/include/linux/trace.h b/include/linux/trace.h index 24fcf07812ae..7fd86d3c691f 100644 --- a/include/linux/trace.h +++ b/include/linux/trace.h @@ -29,7 +29,8 @@ struct trace_array; void trace_printk_init_buffers(void); int trace_array_printk(struct trace_array *tr, unsigned long ip, const char *fmt, ...); -struct trace_array *trace_array_create(const char *name); +void trace_array_put(struct trace_array *tr); +struct trace_array *trace_array_get_by_name(const char *name); int trace_array_destroy(struct trace_array *tr); #endif /* CONFIG_TRACING */ diff --git a/include/linux/trace_events.h b/include/linux/trace_events.h index 60a41b7069dd..4c6e15605766 100644 --- a/include/linux/trace_events.h +++ b/include/linux/trace_events.h @@ -555,7 +555,8 @@ extern int trace_event_get_offsets(struct trace_event_call *call); int ftrace_set_clr_event(struct trace_array *tr, char *buf, int set); int trace_set_clr_event(const char *system, const char *event, int set); - +int trace_array_set_clr_event(struct trace_array *tr, const char *system, + const char *event, bool enable); /* * The double __builtin_constant_p is because gcc will give us an error * if we try to allocate the static variable to fmt if it is not a -- cgit v1.2.3