From f29c50419c8d1998edd759f1990c4243a248f469 Mon Sep 17 00:00:00 2001 From: Steven Rostedt Date: Thu, 19 May 2011 14:35:33 -0400 Subject: maccess,probe_kernel: Make write/read src const void * The functions probe_kernel_write() and probe_kernel_read() do not modify the src pointer. Allow const pointers to be passed in without the need of a typecast. Acked-by: Mike Frysinger Acked-by: Heiko Carstens Acked-by: Martin Schwidefsky Signed-off-by: Steven Rostedt Link: http://lkml.kernel.org/r/1305824936.1465.4.camel@gandalf.stny.rr.com --- arch/blackfin/mm/maccess.c | 4 ++-- arch/s390/mm/maccess.c | 4 ++-- include/linux/uaccess.h | 8 ++++---- mm/maccess.c | 8 ++++---- 4 files changed, 12 insertions(+), 12 deletions(-) diff --git a/arch/blackfin/mm/maccess.c b/arch/blackfin/mm/maccess.c index b71cebc1f8a3..e2532114c5fd 100644 --- a/arch/blackfin/mm/maccess.c +++ b/arch/blackfin/mm/maccess.c @@ -16,7 +16,7 @@ static int validate_memory_access_address(unsigned long addr, int size) return bfin_mem_access_type(addr, size); } -long probe_kernel_read(void *dst, void *src, size_t size) +long probe_kernel_read(void *dst, const void *src, size_t size) { unsigned long lsrc = (unsigned long)src; int mem_type; @@ -55,7 +55,7 @@ long probe_kernel_read(void *dst, void *src, size_t size) return -EFAULT; } -long probe_kernel_write(void *dst, void *src, size_t size) +long probe_kernel_write(void *dst, const void *src, size_t size) { unsigned long ldst = (unsigned long)dst; int mem_type; diff --git a/arch/s390/mm/maccess.c b/arch/s390/mm/maccess.c index 71a4b0d34be0..51e5cd9b906a 100644 --- a/arch/s390/mm/maccess.c +++ b/arch/s390/mm/maccess.c @@ -19,7 +19,7 @@ * using the stura instruction. * Returns the number of bytes copied or -EFAULT. */ -static long probe_kernel_write_odd(void *dst, void *src, size_t size) +static long probe_kernel_write_odd(void *dst, const void *src, size_t size) { unsigned long count, aligned; int offset, mask; @@ -45,7 +45,7 @@ static long probe_kernel_write_odd(void *dst, void *src, size_t size) return rc ? rc : count; } -long probe_kernel_write(void *dst, void *src, size_t size) +long probe_kernel_write(void *dst, const void *src, size_t size) { long copied = 0; diff --git a/include/linux/uaccess.h b/include/linux/uaccess.h index d512d98dfb7d..5ca0951e1855 100644 --- a/include/linux/uaccess.h +++ b/include/linux/uaccess.h @@ -93,8 +93,8 @@ static inline unsigned long __copy_from_user_nocache(void *to, * Safely read from address @src to the buffer at @dst. If a kernel fault * happens, handle that and return -EFAULT. */ -extern long probe_kernel_read(void *dst, void *src, size_t size); -extern long __probe_kernel_read(void *dst, void *src, size_t size); +extern long probe_kernel_read(void *dst, const void *src, size_t size); +extern long __probe_kernel_read(void *dst, const void *src, size_t size); /* * probe_kernel_write(): safely attempt to write to a location @@ -105,7 +105,7 @@ extern long __probe_kernel_read(void *dst, void *src, size_t size); * Safely write to address @dst from the buffer at @src. If a kernel fault * happens, handle that and return -EFAULT. */ -extern long notrace probe_kernel_write(void *dst, void *src, size_t size); -extern long notrace __probe_kernel_write(void *dst, void *src, size_t size); +extern long notrace probe_kernel_write(void *dst, const void *src, size_t size); +extern long notrace __probe_kernel_write(void *dst, const void *src, size_t size); #endif /* __LINUX_UACCESS_H__ */ diff --git a/mm/maccess.c b/mm/maccess.c index e2b6f5634e0d..4cee182ab5f3 100644 --- a/mm/maccess.c +++ b/mm/maccess.c @@ -15,10 +15,10 @@ * happens, handle that and return -EFAULT. */ -long __weak probe_kernel_read(void *dst, void *src, size_t size) +long __weak probe_kernel_read(void *dst, const void *src, size_t size) __attribute__((alias("__probe_kernel_read"))); -long __probe_kernel_read(void *dst, void *src, size_t size) +long __probe_kernel_read(void *dst, const void *src, size_t size) { long ret; mm_segment_t old_fs = get_fs(); @@ -43,10 +43,10 @@ EXPORT_SYMBOL_GPL(probe_kernel_read); * Safely write to address @dst from the buffer at @src. If a kernel fault * happens, handle that and return -EFAULT. */ -long __weak probe_kernel_write(void *dst, void *src, size_t size) +long __weak probe_kernel_write(void *dst, const void *src, size_t size) __attribute__((alias("__probe_kernel_write"))); -long __probe_kernel_write(void *dst, void *src, size_t size) +long __probe_kernel_write(void *dst, const void *src, size_t size) { long ret; mm_segment_t old_fs = get_fs(); -- cgit v1.2.3 From 0d098a7d1e39553e8a3f638b923551edec4868a7 Mon Sep 17 00:00:00 2001 From: Rakib Mullick Date: Thu, 12 May 2011 23:33:40 +0600 Subject: x86/ftrace: Fix compiler warning in ftrace.c MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Due to commit dc326fca2b64 (x86, cpu: Clean up and unify the NOP selection infrastructure), we get the following warning: arch/x86/kernel/ftrace.c: In function ‘ftrace_make_nop’: arch/x86/kernel/ftrace.c:308:6: warning: assignment discards qualifiers from pointer target type arch/x86/kernel/ftrace.c: In function ‘ftrace_make_call’: arch/x86/kernel/ftrace.c:318:6: warning: assignment discards qualifiers from pointer target type ftrace_nop_replace() now returns const unsigned char *, so change its associated function/variable to its compatible type to keep compiler clam. Signed-off-by: Rakib Mullick Link: http://lkml.kernel.org/r/1305221620.7986.4.camel@localhost.localdomain [ updated for change of const void *src in probe_kernel_write() ] Signed-off-by: Steven Rostedt --- arch/x86/kernel/ftrace.c | 12 ++++++------ 1 file changed, 6 insertions(+), 6 deletions(-) diff --git a/arch/x86/kernel/ftrace.c b/arch/x86/kernel/ftrace.c index 0ba15a6cc57e..c9a281f272fd 100644 --- a/arch/x86/kernel/ftrace.c +++ b/arch/x86/kernel/ftrace.c @@ -123,7 +123,7 @@ static unsigned char *ftrace_call_replace(unsigned long ip, unsigned long addr) static atomic_t nmi_running = ATOMIC_INIT(0); static int mod_code_status; /* holds return value of text write */ static void *mod_code_ip; /* holds the IP to write to */ -static void *mod_code_newcode; /* holds the text to write to the IP */ +static const void *mod_code_newcode; /* holds the text to write to the IP */ static unsigned nmi_wait_count; static atomic_t nmi_update_count = ATOMIC_INIT(0); @@ -225,7 +225,7 @@ within(unsigned long addr, unsigned long start, unsigned long end) } static int -do_ftrace_mod_code(unsigned long ip, void *new_code) +do_ftrace_mod_code(unsigned long ip, const void *new_code) { /* * On x86_64, kernel text mappings are mapped read-only with @@ -266,8 +266,8 @@ static const unsigned char *ftrace_nop_replace(void) } static int -ftrace_modify_code(unsigned long ip, unsigned char *old_code, - unsigned char *new_code) +ftrace_modify_code(unsigned long ip, unsigned const char *old_code, + unsigned const char *new_code) { unsigned char replaced[MCOUNT_INSN_SIZE]; @@ -301,7 +301,7 @@ ftrace_modify_code(unsigned long ip, unsigned char *old_code, int ftrace_make_nop(struct module *mod, struct dyn_ftrace *rec, unsigned long addr) { - unsigned char *new, *old; + unsigned const char *new, *old; unsigned long ip = rec->ip; old = ftrace_call_replace(ip, addr); @@ -312,7 +312,7 @@ int ftrace_make_nop(struct module *mod, int ftrace_make_call(struct dyn_ftrace *rec, unsigned long addr) { - unsigned char *new, *old; + unsigned const char *new, *old; unsigned long ip = rec->ip; old = ftrace_nop_replace(); -- cgit v1.2.3 From 50d6828e898590fc5d038810334695380baa1c78 Mon Sep 17 00:00:00 2001 From: Steven Rostedt Date: Thu, 19 May 2011 14:41:17 -0400 Subject: scripts/tags.sh: Fix ctags for DEFINE_EVENT() The regex to handle DEFINE_EVENT() should not be the same as the TRACE_EVENT() as the first parameter in DEFINE_EVENT is the template name, not the event name. We need the second parameter as that is what the trace_... will use. Tested-by: Peter Zijlstra Signed-off-by: Steven Rostedt --- scripts/tags.sh | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/scripts/tags.sh b/scripts/tags.sh index bd6185d529cf..33b53cab5dbf 100755 --- a/scripts/tags.sh +++ b/scripts/tags.sh @@ -132,7 +132,7 @@ exuberant() --regex-asm='/^ENTRY\(([^)]*)\).*/\1/' \ --regex-c='/^SYSCALL_DEFINE[[:digit:]]?\(([^,)]*).*/sys_\1/' \ --regex-c++='/^TRACE_EVENT\(([^,)]*).*/trace_\1/' \ - --regex-c++='/^DEFINE_EVENT\(([^,)]*).*/trace_\1/' + --regex-c++='/^DEFINE_EVENT\([^,)]*, *([^,)]*).*/trace_\1/' all_kconfigs | xargs $1 -a \ --langdef=kconfig --language-force=kconfig \ -- cgit v1.2.3 From 4d7a2fa876d1a615649761dc465708d0a062249a Mon Sep 17 00:00:00 2001 From: Steven Rostedt Date: Thu, 19 May 2011 14:43:57 -0400 Subject: scripts/tags.sh: Add magic for trace-events for etags too Seems that Peter Zijlstra treats us emacs users as second class citizens and the commit: commit 15664125f7cadcb6d725cb2d9b90f9715397848d Author: Peter Zijlstra scripts/tags.sh: Add magic for trace-events only updated ctags (for vim) and did not do the work to let us lowly emacs users benefit from such a change. Cc: Peter Zijlstra Signed-off-by: Steven Rostedt --- scripts/tags.sh | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/scripts/tags.sh b/scripts/tags.sh index 33b53cab5dbf..75c5d24f1993 100755 --- a/scripts/tags.sh +++ b/scripts/tags.sh @@ -152,7 +152,9 @@ emacs() { all_sources | xargs $1 -a \ --regex='/^ENTRY(\([^)]*\)).*/\1/' \ - --regex='/^SYSCALL_DEFINE[0-9]?(\([^,)]*\).*/sys_\1/' + --regex='/^SYSCALL_DEFINE[0-9]?(\([^,)]*\).*/sys_\1/' \ + --regex='/^TRACE_EVENT(\([^,)]*\).*/trace_\1/' \ + --regex='/^DEFINE_EVENT([^,)]*, *\([^,)]*\).*/trace_\1/' all_kconfigs | xargs $1 -a \ --regex='/^[ \t]*\(\(menu\)*config\)[ \t]+\([a-zA-Z0-9_]+\)/\3/' -- cgit v1.2.3 From 9905ce8ad7b79dddd23c7b4753d0b2cdb65bde3c Mon Sep 17 00:00:00 2001 From: Rabin Vincent Date: Wed, 11 May 2011 22:53:51 +0530 Subject: ftrace/recordmcount: Avoid STT_FUNC symbols as base on ARM While find_secsym_ndx often finds the unamed local STT_SECTION, if a section has only one function in it, the ARM toolchain generates the STT_FUNC symbol before the STT_SECTION, and recordmcount finds this instead. This is problematic on ARM because in ARM ELFs, "if a [STT_FUNC] symbol addresses a Thumb instruction, its value is the address of the instruction with bit zero set (in a relocatable object, the section offset with bit zero set)". This leads to incorrect mcount addresses being recorded. Fix this by not using STT_FUNC symbols as the base on ARM. Signed-off-by: Rabin Vincent Link: http://lkml.kernel.org/r/1305134631-31617-1-git-send-email-rabin@rab.in Signed-off-by: Steven Rostedt --- scripts/recordmcount.h | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/scripts/recordmcount.h b/scripts/recordmcount.h index 4be60364a405..f40a6af6bf40 100644 --- a/scripts/recordmcount.h +++ b/scripts/recordmcount.h @@ -43,6 +43,7 @@ #undef ELF_R_INFO #undef Elf_r_info #undef ELF_ST_BIND +#undef ELF_ST_TYPE #undef fn_ELF_R_SYM #undef fn_ELF_R_INFO #undef uint_t @@ -76,6 +77,7 @@ # define ELF_R_INFO ELF64_R_INFO # define Elf_r_info Elf64_r_info # define ELF_ST_BIND ELF64_ST_BIND +# define ELF_ST_TYPE ELF64_ST_TYPE # define fn_ELF_R_SYM fn_ELF64_R_SYM # define fn_ELF_R_INFO fn_ELF64_R_INFO # define uint_t uint64_t @@ -108,6 +110,7 @@ # define ELF_R_INFO ELF32_R_INFO # define Elf_r_info Elf32_r_info # define ELF_ST_BIND ELF32_ST_BIND +# define ELF_ST_TYPE ELF32_ST_TYPE # define fn_ELF_R_SYM fn_ELF32_R_SYM # define fn_ELF_R_INFO fn_ELF32_R_INFO # define uint_t uint32_t @@ -427,6 +430,11 @@ static unsigned find_secsym_ndx(unsigned const txtndx, if (txtndx == w2(symp->st_shndx) /* avoid STB_WEAK */ && (STB_LOCAL == st_bind || STB_GLOBAL == st_bind)) { + /* function symbols on ARM have quirks, avoid them */ + if (w2(ehdr->e_machine) == EM_ARM + && ELF_ST_TYPE(symp->st_info) == STT_FUNC) + continue; + *recvalp = _w(symp->st_value); return symp - sym0; } -- cgit v1.2.3 From 7cbc5b8d4a775a43875a09e29c49a2a8195b5b2d Mon Sep 17 00:00:00 2001 From: Jiri Olsa Date: Tue, 10 May 2011 12:43:46 +0200 Subject: jump_label: Check entries limit in __jump_label_update When iterating the jump_label entries array (core or modules), the __jump_label_update function peeks over the last entry. The reason is that the end of the for loop depends on the key value of the processed entry. Thus when going through the last array entry, we will touch the memory behind the array limit. This bug probably will never be triggered, since most likely the memory behind the jump_label entries will be accesable and the entry->key will be different than the expected value. Signed-off-by: Jiri Olsa Acked-by: Jason Baron Link: http://lkml.kernel.org/r/20110510104346.GC1899@jolsa.brq.redhat.com Signed-off-by: Steven Rostedt --- kernel/jump_label.c | 18 +++++++++++++----- 1 file changed, 13 insertions(+), 5 deletions(-) diff --git a/kernel/jump_label.c b/kernel/jump_label.c index 74d1c099fbd1..fa27e750dbc0 100644 --- a/kernel/jump_label.c +++ b/kernel/jump_label.c @@ -105,9 +105,12 @@ static int __jump_label_text_reserved(struct jump_entry *iter_start, } static void __jump_label_update(struct jump_label_key *key, - struct jump_entry *entry, int enable) + struct jump_entry *entry, + struct jump_entry *stop, int enable) { - for (; entry->key == (jump_label_t)(unsigned long)key; entry++) { + for (; (entry < stop) && + (entry->key == (jump_label_t)(unsigned long)key); + entry++) { /* * entry->code set to 0 invalidates module init text sections * kernel_text_address() verifies we are not in core kernel @@ -181,7 +184,11 @@ static void __jump_label_mod_update(struct jump_label_key *key, int enable) struct jump_label_mod *mod = key->next; while (mod) { - __jump_label_update(key, mod->entries, enable); + struct module *m = mod->mod; + + __jump_label_update(key, mod->entries, + m->jump_entries + m->num_jump_entries, + enable); mod = mod->next; } } @@ -245,7 +252,8 @@ static int jump_label_add_module(struct module *mod) key->next = jlm; if (jump_label_enabled(key)) - __jump_label_update(key, iter, JUMP_LABEL_ENABLE); + __jump_label_update(key, iter, iter_stop, + JUMP_LABEL_ENABLE); } return 0; @@ -371,7 +379,7 @@ static void jump_label_update(struct jump_label_key *key, int enable) /* if there are no users, entry can be NULL */ if (entry) - __jump_label_update(key, entry, enable); + __jump_label_update(key, entry, __stop___jump_table, enable); #ifdef CONFIG_MODULES __jump_label_mod_update(key, enable); -- cgit v1.2.3 From a1cd6173596c6f7d1f0b41ac7d33ecf03c581edc Mon Sep 17 00:00:00 2001 From: Steven Rostedt Date: Mon, 23 May 2011 15:24:25 -0400 Subject: ftrace: Have ftrace_startup() return failure code The register_ftrace_function() returns an error code on failure except if the call to ftrace_startup() fails. Add a error return to ftrace_startup() if it fails to start, allowing register_ftrace_funtion() to return a proper error value. Signed-off-by: Steven Rostedt --- kernel/trace/ftrace.c | 14 ++++++++------ 1 file changed, 8 insertions(+), 6 deletions(-) diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c index d017c2c82c44..bebbc959ee8c 100644 --- a/kernel/trace/ftrace.c +++ b/kernel/trace/ftrace.c @@ -1638,12 +1638,12 @@ static void ftrace_startup_enable(int command) ftrace_run_update_code(command); } -static void ftrace_startup(struct ftrace_ops *ops, int command) +static int ftrace_startup(struct ftrace_ops *ops, int command) { bool hash_enable = true; if (unlikely(ftrace_disabled)) - return; + return -ENODEV; ftrace_start_up++; command |= FTRACE_ENABLE_CALLS; @@ -1662,6 +1662,8 @@ static void ftrace_startup(struct ftrace_ops *ops, int command) ftrace_hash_rec_enable(ops, 1); ftrace_startup_enable(command); + + return 0; } static void ftrace_shutdown(struct ftrace_ops *ops, int command) @@ -2501,7 +2503,7 @@ static void __enable_ftrace_function_probe(void) ret = __register_ftrace_function(&trace_probe_ops); if (!ret) - ftrace_startup(&trace_probe_ops, 0); + ret = ftrace_startup(&trace_probe_ops, 0); ftrace_probe_registered = 1; } @@ -3466,7 +3468,7 @@ device_initcall(ftrace_nodyn_init); static inline int ftrace_init_dyn_debugfs(struct dentry *d_tracer) { return 0; } static inline void ftrace_startup_enable(int command) { } /* Keep as macros so we do not need to define the commands */ -# define ftrace_startup(ops, command) do { } while (0) +# define ftrace_startup(ops, command) ({0;}) # define ftrace_shutdown(ops, command) do { } while (0) # define ftrace_startup_sysctl() do { } while (0) # define ftrace_shutdown_sysctl() do { } while (0) @@ -3799,7 +3801,7 @@ int register_ftrace_function(struct ftrace_ops *ops) ret = __register_ftrace_function(ops); if (!ret) - ftrace_startup(ops, 0); + ret = ftrace_startup(ops, 0); out_unlock: @@ -4045,7 +4047,7 @@ int register_ftrace_graph(trace_func_graph_ret_t retfunc, ftrace_graph_return = retfunc; ftrace_graph_entry = entryfunc; - ftrace_startup(&global_ops, FTRACE_START_FUNC_RET); + ret = ftrace_startup(&global_ops, FTRACE_START_FUNC_RET); out: mutex_unlock(&ftrace_lock); -- cgit v1.2.3 From 17bb615ad4f8d2d2c0f02794d27d7f83e0009ef4 Mon Sep 17 00:00:00 2001 From: Steven Rostedt Date: Mon, 23 May 2011 15:27:46 -0400 Subject: tracing: Have event with function tracer check error return The self tests for event tracer does not check if the function tracing was successfully activated. It needs to before it continues the tests, otherwise the wrong errors may be reported. Signed-off-by: Steven Rostedt --- kernel/trace/trace_events.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) diff --git a/kernel/trace/trace_events.c b/kernel/trace/trace_events.c index 2fe110341359..686ec399f2a8 100644 --- a/kernel/trace/trace_events.c +++ b/kernel/trace/trace_events.c @@ -1657,7 +1657,12 @@ static struct ftrace_ops trace_ops __initdata = static __init void event_trace_self_test_with_function(void) { - register_ftrace_function(&trace_ops); + int ret; + ret = register_ftrace_function(&trace_ops); + if (WARN_ON(ret < 0)) { + pr_info("Failed to enable function tracer for event tests\n"); + return; + } pr_info("Running tests again, along with the function tracer\n"); event_trace_self_tests(); unregister_ftrace_function(&trace_ops); -- cgit v1.2.3 From 3b6cfdb1714a33ae4d2ca9fbc818a42cf7adee69 Mon Sep 17 00:00:00 2001 From: Steven Rostedt Date: Mon, 23 May 2011 15:33:49 -0400 Subject: ftrace: Set ops->flag to enabled even on static function tracing When dynamic ftrace is not configured, the ops->flags still needs to have its FTRACE_OPS_FL_ENABLED bit set in ftrace_startup(). Signed-off-by: Steven Rostedt --- kernel/trace/ftrace.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c index bebbc959ee8c..25949b33057c 100644 --- a/kernel/trace/ftrace.c +++ b/kernel/trace/ftrace.c @@ -3468,7 +3468,11 @@ device_initcall(ftrace_nodyn_init); static inline int ftrace_init_dyn_debugfs(struct dentry *d_tracer) { return 0; } static inline void ftrace_startup_enable(int command) { } /* Keep as macros so we do not need to define the commands */ -# define ftrace_startup(ops, command) ({0;}) +# define ftrace_startup(ops, command) \ + ({ \ + (ops)->flags |= FTRACE_OPS_FL_ENABLED; \ + 0; \ + }) # define ftrace_shutdown(ops, command) do { } while (0) # define ftrace_startup_sysctl() do { } while (0) # define ftrace_shutdown_sysctl() do { } while (0) -- cgit v1.2.3 From 2fc1b6f0d0a719e1e2a30bf076a3a799feaf6af2 Mon Sep 17 00:00:00 2001 From: liubo Date: Tue, 19 Apr 2011 09:35:28 +0800 Subject: tracing: Add __print_symbolic_u64 to avoid warnings on 32bit machine Filesystem, like Btrfs, has some "ULL" macros, and when these macros are passed to tracepoints'__print_symbolic(), there will be 64->32 truncate WARNINGS during compiling on 32bit box. Signed-off-by: Liu Bo Link: http://lkml.kernel.org/r/4DACE6E0.7000507@cn.fujitsu.com Signed-off-by: Steven Rostedt --- include/linux/ftrace_event.h | 12 ++++++++++++ include/trace/ftrace.h | 13 +++++++++++++ kernel/trace/trace_output.c | 27 +++++++++++++++++++++++++++ 3 files changed, 52 insertions(+) diff --git a/include/linux/ftrace_event.h b/include/linux/ftrace_event.h index b5a550a39a70..59d3ef100eb9 100644 --- a/include/linux/ftrace_event.h +++ b/include/linux/ftrace_event.h @@ -16,6 +16,11 @@ struct trace_print_flags { const char *name; }; +struct trace_print_flags_u64 { + unsigned long long mask; + const char *name; +}; + const char *ftrace_print_flags_seq(struct trace_seq *p, const char *delim, unsigned long flags, const struct trace_print_flags *flag_array); @@ -23,6 +28,13 @@ const char *ftrace_print_flags_seq(struct trace_seq *p, const char *delim, const char *ftrace_print_symbols_seq(struct trace_seq *p, unsigned long val, const struct trace_print_flags *symbol_array); +#if BITS_PER_LONG == 32 +const char *ftrace_print_symbols_seq_u64(struct trace_seq *p, + unsigned long long val, + const struct trace_print_flags_u64 + *symbol_array); +#endif + const char *ftrace_print_hex_seq(struct trace_seq *p, const unsigned char *buf, int len); diff --git a/include/trace/ftrace.h b/include/trace/ftrace.h index 3e68366d485a..533c49f48047 100644 --- a/include/trace/ftrace.h +++ b/include/trace/ftrace.h @@ -205,6 +205,19 @@ ftrace_print_symbols_seq(p, value, symbols); \ }) +#undef __print_symbolic_u64 +#if BITS_PER_LONG == 32 +#define __print_symbolic_u64(value, symbol_array...) \ + ({ \ + static const struct trace_print_flags_u64 symbols[] = \ + { symbol_array, { -1, NULL } }; \ + ftrace_print_symbols_seq_u64(p, value, symbols); \ + }) +#else +#define __print_symbolic_u64(value, symbol_array...) \ + __print_symbolic(value, symbol_array) +#endif + #undef __print_hex #define __print_hex(buf, buf_len) ftrace_print_hex_seq(p, buf, buf_len) diff --git a/kernel/trace/trace_output.c b/kernel/trace/trace_output.c index cf535ccedc86..e37de492a9e1 100644 --- a/kernel/trace/trace_output.c +++ b/kernel/trace/trace_output.c @@ -353,6 +353,33 @@ ftrace_print_symbols_seq(struct trace_seq *p, unsigned long val, } EXPORT_SYMBOL(ftrace_print_symbols_seq); +#if BITS_PER_LONG == 32 +const char * +ftrace_print_symbols_seq_u64(struct trace_seq *p, unsigned long long val, + const struct trace_print_flags_u64 *symbol_array) +{ + int i; + const char *ret = p->buffer + p->len; + + for (i = 0; symbol_array[i].name; i++) { + + if (val != symbol_array[i].mask) + continue; + + trace_seq_puts(p, symbol_array[i].name); + break; + } + + if (!p->len) + trace_seq_printf(p, "0x%llx", val); + + trace_seq_putc(p, 0); + + return ret; +} +EXPORT_SYMBOL(ftrace_print_symbols_seq_u64); +#endif + const char * ftrace_print_hex_seq(struct trace_seq *p, const unsigned char *buf, int buf_len) { -- cgit v1.2.3 From 7f34b746f79c1e1f8fd6d09799d133263ae7a504 Mon Sep 17 00:00:00 2001 From: liubo Date: Tue, 19 Apr 2011 09:35:31 +0800 Subject: tracing: Update btrfs's tracepoints to use u64 interface To avoid 64->32 truncating WARNING, update btrfs's tracepoints. Signed-off-by: Liu Bo Link: http://lkml.kernel.org/r/4DACE6E3.8080200@cn.fujitsu.com Signed-off-by: Steven Rostedt --- include/trace/events/btrfs.h | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/include/trace/events/btrfs.h b/include/trace/events/btrfs.h index f445cff66ab7..4114129f0794 100644 --- a/include/trace/events/btrfs.h +++ b/include/trace/events/btrfs.h @@ -28,7 +28,7 @@ struct extent_buffer; { BTRFS_SHARED_DATA_REF_KEY, "SHARED_DATA_REF" }) #define __show_root_type(obj) \ - __print_symbolic(obj, \ + __print_symbolic_u64(obj, \ { BTRFS_ROOT_TREE_OBJECTID, "ROOT_TREE" }, \ { BTRFS_EXTENT_TREE_OBJECTID, "EXTENT_TREE" }, \ { BTRFS_CHUNK_TREE_OBJECTID, "CHUNK_TREE" }, \ @@ -125,7 +125,7 @@ DEFINE_EVENT(btrfs__inode, btrfs_inode_evict, ); #define __show_map_type(type) \ - __print_symbolic(type, \ + __print_symbolic_u64(type, \ { EXTENT_MAP_LAST_BYTE, "LAST_BYTE" }, \ { EXTENT_MAP_HOLE, "HOLE" }, \ { EXTENT_MAP_INLINE, "INLINE" }, \ -- cgit v1.2.3 From b1cff0ad1062621ae63cb6c5dc4165191fe2e9f1 Mon Sep 17 00:00:00 2001 From: Steven Rostedt Date: Wed, 25 May 2011 14:27:43 -0400 Subject: ftrace: Add internal recursive checks Witold reported a reboot caused by the selftests of the dynamic function tracer. He sent me a config and I used ktest to do a config_bisect on it (as my config did not cause the crash). It pointed out that the problem config was CONFIG_PROVE_RCU. What happened was that if multiple callbacks are attached to the function tracer, we iterate a list of callbacks. Because the list is managed by synchronize_sched() and preempt_disable, the access to the pointers uses rcu_dereference_raw(). When PROVE_RCU is enabled, the rcu_dereference_raw() calls some debugging functions, which happen to be traced. The tracing of the debug function would then call rcu_dereference_raw() which would then call the debug function and then... well you get the idea. I first wrote two different patches to solve this bug. 1) add a __rcu_dereference_raw() that would not do any checks. 2) add notrace to the offending debug functions. Both of these patches worked. Talking with Paul McKenney on IRC, he suggested to add recursion detection instead. This seemed to be a better solution, so I decided to implement it. As the task_struct already has a trace_recursion to detect recursion in the ring buffer, and that has a very small number it allows, I decided to use that same variable to add flags that can detect the recursion inside the infrastructure of the function tracer. I plan to change it so that the task struct bit can be checked in mcount, but as that requires changes to all archs, I will hold that off to the next merge window. Cc: Ingo Molnar Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: Frederic Weisbecker Cc: Paul E. McKenney Link: http://lkml.kernel.org/r/1306348063.1465.116.camel@gandalf.stny.rr.com Reported-by: Witold Baryluk Signed-off-by: Steven Rostedt --- include/linux/sched.h | 2 +- kernel/trace/ftrace.c | 13 ++++++++++++- kernel/trace/ring_buffer.c | 10 +++++----- kernel/trace/trace.h | 15 +++++++++++++++ 4 files changed, 33 insertions(+), 7 deletions(-) diff --git a/include/linux/sched.h b/include/linux/sched.h index d8b2d0bec0d8..7b78d9cad471 100644 --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -1513,7 +1513,7 @@ struct task_struct { #ifdef CONFIG_TRACING /* state flags for use by tracers */ unsigned long trace; - /* bitmask of trace recursion */ + /* bitmask and counter of trace recursion */ unsigned long trace_recursion; #endif /* CONFIG_TRACING */ #ifdef CONFIG_CGROUP_MEM_RES_CTLR /* memcg uses this to do batch job */ diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c index 25949b33057c..1ee417fcbfa5 100644 --- a/kernel/trace/ftrace.c +++ b/kernel/trace/ftrace.c @@ -109,12 +109,18 @@ ftrace_ops_list_func(unsigned long ip, unsigned long parent_ip); static void ftrace_global_list_func(unsigned long ip, unsigned long parent_ip) { - struct ftrace_ops *op = rcu_dereference_raw(ftrace_global_list); /*see above*/ + struct ftrace_ops *op; + + if (unlikely(trace_recursion_test(TRACE_GLOBAL_BIT))) + return; + trace_recursion_set(TRACE_GLOBAL_BIT); + op = rcu_dereference_raw(ftrace_global_list); /*see above*/ while (op != &ftrace_list_end) { op->func(ip, parent_ip); op = rcu_dereference_raw(op->next); /*see above*/ }; + trace_recursion_clear(TRACE_GLOBAL_BIT); } static void ftrace_pid_func(unsigned long ip, unsigned long parent_ip) @@ -3490,6 +3496,10 @@ ftrace_ops_list_func(unsigned long ip, unsigned long parent_ip) { struct ftrace_ops *op; + if (unlikely(trace_recursion_test(TRACE_INTERNAL_BIT))) + return; + + trace_recursion_set(TRACE_INTERNAL_BIT); /* * Some of the ops may be dynamically allocated, * they must be freed after a synchronize_sched(). @@ -3502,6 +3512,7 @@ ftrace_ops_list_func(unsigned long ip, unsigned long parent_ip) op = rcu_dereference_raw(op->next); }; preempt_enable_notrace(); + trace_recursion_clear(TRACE_INTERNAL_BIT); } static void clear_ftrace_swapper(void) diff --git a/kernel/trace/ring_buffer.c b/kernel/trace/ring_buffer.c index 0ef7b4b2a1f7..b0c7aa407943 100644 --- a/kernel/trace/ring_buffer.c +++ b/kernel/trace/ring_buffer.c @@ -2216,7 +2216,7 @@ static noinline void trace_recursive_fail(void) printk_once(KERN_WARNING "Tracing recursion: depth[%ld]:" "HC[%lu]:SC[%lu]:NMI[%lu]\n", - current->trace_recursion, + trace_recursion_buffer(), hardirq_count() >> HARDIRQ_SHIFT, softirq_count() >> SOFTIRQ_SHIFT, in_nmi()); @@ -2226,9 +2226,9 @@ static noinline void trace_recursive_fail(void) static inline int trace_recursive_lock(void) { - current->trace_recursion++; + trace_recursion_inc(); - if (likely(current->trace_recursion < TRACE_RECURSIVE_DEPTH)) + if (likely(trace_recursion_buffer() < TRACE_RECURSIVE_DEPTH)) return 0; trace_recursive_fail(); @@ -2238,9 +2238,9 @@ static inline int trace_recursive_lock(void) static inline void trace_recursive_unlock(void) { - WARN_ON_ONCE(!current->trace_recursion); + WARN_ON_ONCE(!trace_recursion_buffer()); - current->trace_recursion--; + trace_recursion_dec(); } #else diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h index 6b69c4bd306f..229f8591f61d 100644 --- a/kernel/trace/trace.h +++ b/kernel/trace/trace.h @@ -784,4 +784,19 @@ extern const char *__stop___trace_bprintk_fmt[]; FTRACE_ENTRY(call, struct_name, id, PARAMS(tstruct), PARAMS(print)) #include "trace_entries.h" +/* Only current can touch trace_recursion */ +#define trace_recursion_inc() do { (current)->trace_recursion++; } while (0) +#define trace_recursion_dec() do { (current)->trace_recursion--; } while (0) + +/* Ring buffer has the 10 LSB bits to count */ +#define trace_recursion_buffer() ((current)->trace_recursion & 0x3ff) + +/* for function tracing recursion */ +#define TRACE_INTERNAL_BIT (1<<11) +#define TRACE_GLOBAL_BIT (1<<12) + +#define trace_recursion_set(bit) do { (current)->trace_recursion |= (bit); } while (0) +#define trace_recursion_clear(bit) do { (current)->trace_recursion &= ~(bit); } while (0) +#define trace_recursion_test(bit) ((current)->trace_recursion & (bit)) + #endif /* _LINUX_KERNEL_TRACE_H */ -- cgit v1.2.3