diff options
Diffstat (limited to 'runtime/sym.c')
| -rw-r--r-- | runtime/sym.c | 220 |
1 files changed, 166 insertions, 54 deletions
diff --git a/runtime/sym.c b/runtime/sym.c index 31700326..386005b2 100644 --- a/runtime/sym.c +++ b/runtime/sym.c @@ -14,6 +14,7 @@ #include "sym.h" #include "string.c" +#include "task_finder_vma.c" /** @file sym.c * @addtogroup sym Symbolic Functions @@ -21,6 +22,62 @@ * @{ */ +static void _stp_sym_init(void) +{ + static int initialized = 0; + if (! initialized) { + __stp_tf_vma_initialize(); + initialized = 1; + } +} + +/* Callback that needs to be registered (in tapsets.cxx for + emit_module_init) for every user task path or pid for which we + might need symbols or unwind info. */ +static int _stp_tf_mmap_cb(struct stap_task_finder_target *tgt, + struct task_struct *tsk, + char *path, + unsigned long addr, + unsigned long length, + unsigned long offset, + unsigned long vm_flags) +{ + int i; + struct _stp_module *module = NULL; + +#ifdef DEBUG_TASK_FINDER_VMA + _stp_dbug(__FUNCTION__, __LINE__, + "mmap_cb: tsk %d:%d path %s, addr 0x%08lx, length 0x%08lx, offset 0x%lx, flags 0x%lx\n", + tsk->pid, tsk->tgid, path, addr, length, offset, vm_flags); +#endif + if (path != NULL) { + for (i = 0; i < _stp_num_modules; i++) { + if (strcmp(path, _stp_modules[i]->path) == 0) + { +#ifdef DEBUG_TASK_FINDER_VMA + _stp_dbug(__FUNCTION__, __LINE__, + "vm_cb: matched path %s to module\n", + path); +#endif + module = _stp_modules[i]; + break; + } + } + } + stap_add_vma_map_info(tsk->group_leader, addr, addr + length, offset, + module); + return 0; +} + +static int _stp_tf_munmap_cb(struct stap_task_finder_target *tgt, + struct task_struct *tsk, + unsigned long addr, + unsigned long length) +{ + stap_remove_vma_map_info(tsk->group_leader, addr, addr + length, 0); + return 0; +} + /* XXX: this needs to be address-space-specific. */ static unsigned long _stp_module_relocate(const char *module, const char *section, unsigned long offset) { @@ -72,35 +129,54 @@ static unsigned long _stp_module_relocate(const char *module, const char *sectio return 0; } - -/* Return module owner and fills in closest section of the address - if found, return NULL otherwise. +/* Return module owner and, if sec != NULL, fills in closest section + of the address if found, return NULL otherwise. XXX: needs to be address-space-specific. */ static struct _stp_module *_stp_mod_sec_lookup(unsigned long addr, + struct task_struct *task, struct _stp_section **sec) { - struct _stp_module *m = NULL; + void *user = NULL; unsigned midx = 0; - unsigned long closest_section_offset = ~0; + + // Try vma matching first if task given. + if (task) + { + unsigned long vm_start = 0; + if (stap_find_vma_map_info(task->group_leader, addr, + &vm_start, NULL, + NULL, &user) == 0) + if (user != NULL) + { + struct _stp_module *m = (struct _stp_module *)user; + if (sec) + *sec = &m->sections[0]; // XXX check actual section and relocate + dbug_sym(1, "found section %s in module %s at 0x%lx\n", + m->sections[0].name, m->name, vm_start); + if (strcmp(".dynamic", m->sections[0].name) == 0) + m->sections[0].addr = vm_start; // cheat... + return m; + } + } + for (midx = 0; midx < _stp_num_modules; midx++) { unsigned secidx; for (secidx = 0; secidx < _stp_modules[midx]->num_sections; secidx++) { - unsigned long this_section_addr; - unsigned long this_section_offset; - this_section_addr = _stp_modules[midx]->sections[secidx].addr; - if (addr < this_section_addr) continue; - this_section_offset = addr - this_section_addr; - if (this_section_offset < closest_section_offset) - { - closest_section_offset = this_section_offset; - m = _stp_modules[midx]; - *sec = & m->sections[secidx]; + unsigned long sec_addr; + unsigned long sec_size; + sec_addr = _stp_modules[midx]->sections[secidx].addr; + sec_size = _stp_modules[midx]->sections[secidx].size; + if (addr >= sec_addr && addr < sec_addr + sec_size) + { + if (sec) + *sec = & _stp_modules[midx]->sections[secidx]; + return _stp_modules[midx]; } } } - return m; + return NULL; } @@ -109,14 +185,15 @@ static const char *_stp_kallsyms_lookup(unsigned long addr, unsigned long *symbo unsigned long *offset, const char **modname, /* char ** secname? */ - char *namebuf) + char *namebuf, + struct task_struct *task) { struct _stp_module *m = NULL; struct _stp_section *sec = NULL; struct _stp_symbol *s = NULL; unsigned end, begin = 0; - m = _stp_mod_sec_lookup(addr, &sec); + m = _stp_mod_sec_lookup(addr, task, &sec); if (unlikely (m == NULL || sec == NULL)) return NULL; @@ -195,34 +272,29 @@ static int _stp_module_check(void) dwfl_module_build_id was not intended to return the end address. */ notes_addr -= m->build_id_len; - if (notes_addr > base_addr) { - for (j = 0; j < m->build_id_len; j++) - { - unsigned char theory, practice; - theory = m->build_id_bits [j]; - practice = ((unsigned char*) notes_addr) [j]; - /* XXX: consider using kread() instead of above. */ - if (theory != practice) - { - #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,27) - _stp_error ("%s: inconsistent %s build-id byte #%d " - "(0x%x [actual] vs. 0x%x [debuginfo])\n", - THIS_MODULE->name, m->name, j, - practice, theory); - return 1; - #else - /* This branch is a surrogate for - kernels affected by Fedora bug - #465873. */ - printk(KERN_WARNING - "%s: inconsistent %s build-id byte #%d " - "(0x%x [actual] vs. 0x%x [debuginfo])\n", - THIS_MODULE->name, m->name, j, - practice, theory); - break; /* Note just the first mismatch. */ - #endif - } - } + if (notes_addr <= base_addr) /* shouldn't happen */ + continue; + if (memcmp(m->build_id_bits, (unsigned char*) notes_addr, m->build_id_len)) { + const char *basename; + + basename = strrchr(m->path, '/'); + if (basename) + basename++; + else + basename = m->path; +#if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,27) + _stp_error ("Build-id mismatch: \"%s\" %.*M" + " vs. \"%s\" %.*M\n", + m->name, m->build_id_len, notes_addr, + basename, m->build_id_len, m->build_id_bits); + return 1; +#else + /* This branch is a surrogate for kernels + * affected by Fedora bug #465873. */ + printk(KERN_WARNING + "Build-id mismatch: \"%s\" vs. \"%s\"\n", + m->name, basename); +#endif } } /* end checking */ } /* end loop */ @@ -241,7 +313,33 @@ static void _stp_symbol_print(unsigned long address) const char *name; unsigned long offset, size; - name = _stp_kallsyms_lookup(address, &size, &offset, &modname, NULL); + name = _stp_kallsyms_lookup(address, &size, &offset, &modname, NULL, NULL); + + _stp_printf("%p", (int64_t) address); + + if (name) { + if (modname && *modname) + _stp_printf(" : %s+%#lx/%#lx [%s]", name, offset, size, modname); + else + _stp_printf(" : %s+%#lx/%#lx", name, offset, size); + } +} + +/** Print an user space address from a specific task symbolically. + * @param address The address to lookup. + * @param task The address to lookup. + * @note Symbolic lookups should not normally be done within + * a probe because it is too time-consuming. Use at module exit time. + */ + +static void _stp_usymbol_print(unsigned long address, struct task_struct *task) +{ + const char *modname; + const char *name; + unsigned long offset, size; + + name = _stp_kallsyms_lookup(address, &size, &offset, &modname, NULL, + task); _stp_printf("%p", (int64_t) address); @@ -254,7 +352,8 @@ static void _stp_symbol_print(unsigned long address) } /* Like _stp_symbol_print, except only print if the address is a valid function address */ -static int _stp_func_print(unsigned long address, int verbose, int exact) +static int _stp_func_print(unsigned long address, int verbose, int exact, + struct task_struct *task) { const char *modname; const char *name; @@ -266,7 +365,7 @@ static int _stp_func_print(unsigned long address, int verbose, int exact) else exstr = " (inexact)"; - name = _stp_kallsyms_lookup(address, &size, &offset, &modname, NULL); + name = _stp_kallsyms_lookup(address, &size, &offset, &modname, NULL, task); if (name) { if (verbose) { @@ -282,16 +381,29 @@ static int _stp_func_print(unsigned long address, int verbose, int exact) return 0; } -static void _stp_symbol_snprint(char *str, size_t len, unsigned long address) +/** Puts symbolic information of an address in a string. + * @param src The string to fill in. + * @param len The length of the given src string. + * @param address The address to lookup. + * @param add_mod Whether to include module name information if found. + */ + +static void _stp_symbol_snprint(char *str, size_t len, unsigned long address, + struct task_struct *task, int add_mod) { const char *modname; const char *name; unsigned long offset, size; - name = _stp_kallsyms_lookup(address, &size, &offset, &modname, NULL); - if (name) - strlcpy(str, name, len); - else + name = _stp_kallsyms_lookup(address, &size, &offset, &modname, NULL, + task); + if (name) { + if (add_mod && modname && *modname) + _stp_snprintf(str, len, "%s %s+%#lx/%#lx", + name, modname, offset, size); + else + strlcpy(str, name, len); + } else _stp_snprintf(str, len, "%p", (int64_t) address); } |