diff options
Diffstat (limited to 'kernel')
| -rw-r--r-- | kernel/debug/debug_core.c | 2 | ||||
| -rw-r--r-- | kernel/debug/gdbstub.c | 189 | ||||
| -rw-r--r-- | kernel/debug/kdb/kdb_main.c | 132 | ||||
| -rw-r--r-- | kernel/trace/Makefile | 3 | ||||
| -rw-r--r-- | kernel/trace/trace.c | 43 | ||||
| -rw-r--r-- | kernel/trace/trace.h | 19 | ||||
| -rw-r--r-- | kernel/trace/trace_kdb.c | 136 |
7 files changed, 437 insertions, 87 deletions
diff --git a/kernel/debug/debug_core.c b/kernel/debug/debug_core.c index 51d14fe87648..3c2d4972d235 100644 --- a/kernel/debug/debug_core.c +++ b/kernel/debug/debug_core.c @@ -605,6 +605,8 @@ cpu_master_loop: if (dbg_kdb_mode) { kgdb_connected = 1; error = kdb_stub(ks); + if (error == -1) + continue; kgdb_connected = 0; } else { error = gdb_serial_stub(ks); diff --git a/kernel/debug/gdbstub.c b/kernel/debug/gdbstub.c index 6e81fd59566b..481a7bd2dfe7 100644 --- a/kernel/debug/gdbstub.c +++ b/kernel/debug/gdbstub.c @@ -52,17 +52,6 @@ static unsigned long gdb_regs[(NUMREGBYTES + * GDB remote protocol parser: */ -static int hex(char ch) -{ - if ((ch >= 'a') && (ch <= 'f')) - return ch - 'a' + 10; - if ((ch >= '0') && (ch <= '9')) - return ch - '0'; - if ((ch >= 'A') && (ch <= 'F')) - return ch - 'A' + 10; - return -1; -} - #ifdef CONFIG_KGDB_KDB static int gdbstub_read_wait(void) { @@ -123,8 +112,8 @@ static void get_packet(char *buffer) buffer[count] = 0; if (ch == '#') { - xmitcsum = hex(gdbstub_read_wait()) << 4; - xmitcsum += hex(gdbstub_read_wait()); + xmitcsum = hex_to_bin(gdbstub_read_wait()) << 4; + xmitcsum += hex_to_bin(gdbstub_read_wait()); if (checksum != xmitcsum) /* failed checksum */ @@ -236,7 +225,7 @@ void gdbstub_msg_write(const char *s, int len) * buf. Return a pointer to the last char put in buf (null). May * return an error. */ -int kgdb_mem2hex(char *mem, char *buf, int count) +char *kgdb_mem2hex(char *mem, char *buf, int count) { char *tmp; int err; @@ -248,17 +237,16 @@ int kgdb_mem2hex(char *mem, char *buf, int count) tmp = buf + count; err = probe_kernel_read(tmp, mem, count); - if (!err) { - while (count > 0) { - buf = pack_hex_byte(buf, *tmp); - tmp++; - count--; - } - - *buf = 0; + if (err) + return NULL; + while (count > 0) { + buf = pack_hex_byte(buf, *tmp); + tmp++; + count--; } + *buf = 0; - return err; + return buf; } /* @@ -280,8 +268,8 @@ int kgdb_hex2mem(char *buf, char *mem, int count) tmp_hex = tmp_raw - 1; while (tmp_hex >= buf) { tmp_raw--; - *tmp_raw = hex(*tmp_hex--); - *tmp_raw |= hex(*tmp_hex--) << 4; + *tmp_raw = hex_to_bin(*tmp_hex--); + *tmp_raw |= hex_to_bin(*tmp_hex--) << 4; } return probe_kernel_write(mem, tmp_raw, count); @@ -304,7 +292,7 @@ int kgdb_hex2long(char **ptr, unsigned long *long_val) (*ptr)++; } while (**ptr) { - hex_val = hex(**ptr); + hex_val = hex_to_bin(**ptr); if (hex_val < 0) break; @@ -339,6 +327,32 @@ static int kgdb_ebin2mem(char *buf, char *mem, int count) return probe_kernel_write(mem, c, size); } +#if DBG_MAX_REG_NUM > 0 +void pt_regs_to_gdb_regs(unsigned long *gdb_regs, struct pt_regs *regs) +{ + int i; + int idx = 0; + char *ptr = (char *)gdb_regs; + + for (i = 0; i < DBG_MAX_REG_NUM; i++) { + dbg_get_reg(i, ptr + idx, regs); + idx += dbg_reg_def[i].size; + } +} + +void gdb_regs_to_pt_regs(unsigned long *gdb_regs, struct pt_regs *regs) +{ + int i; + int idx = 0; + char *ptr = (char *)gdb_regs; + + for (i = 0; i < DBG_MAX_REG_NUM; i++) { + dbg_set_reg(i, ptr + idx, regs); + idx += dbg_reg_def[i].size; + } +} +#endif /* DBG_MAX_REG_NUM > 0 */ + /* Write memory due to an 'M' or 'X' packet. */ static int write_mem_msg(int binary) { @@ -378,28 +392,31 @@ static void error_packet(char *pkt, int error) * remapped to negative TIDs. */ -#define BUF_THREAD_ID_SIZE 16 +#define BUF_THREAD_ID_SIZE 8 static char *pack_threadid(char *pkt, unsigned char *id) { - char *limit; + unsigned char *limit; + int lzero = 1; + + limit = id + (BUF_THREAD_ID_SIZE / 2); + while (id < limit) { + if (!lzero || *id != 0) { + pkt = pack_hex_byte(pkt, *id); + lzero = 0; + } + id++; + } - limit = pkt + BUF_THREAD_ID_SIZE; - while (pkt < limit) - pkt = pack_hex_byte(pkt, *id++); + if (lzero) + pkt = pack_hex_byte(pkt, 0); return pkt; } static void int_to_threadref(unsigned char *id, int value) { - unsigned char *scan; - int i = 4; - - scan = (unsigned char *)id; - while (i--) - *scan++ = 0; - put_unaligned_be32(value, scan); + put_unaligned_be32(value, id); } static struct task_struct *getthread(struct pt_regs *regs, int tid) @@ -463,8 +480,7 @@ static void gdb_cmd_status(struct kgdb_state *ks) pack_hex_byte(&remcom_out_buffer[1], ks->signo); } -/* Handle the 'g' get registers request */ -static void gdb_cmd_getregs(struct kgdb_state *ks) +static void gdb_get_regs_helper(struct kgdb_state *ks) { struct task_struct *thread; void *local_debuggerinfo; @@ -505,6 +521,12 @@ static void gdb_cmd_getregs(struct kgdb_state *ks) */ sleeping_thread_to_gdb_regs(gdb_regs, thread); } +} + +/* Handle the 'g' get registers request */ +static void gdb_cmd_getregs(struct kgdb_state *ks) +{ + gdb_get_regs_helper(ks); kgdb_mem2hex((char *)gdb_regs, remcom_out_buffer, NUMREGBYTES); } @@ -527,13 +549,13 @@ static void gdb_cmd_memread(struct kgdb_state *ks) char *ptr = &remcom_in_buffer[1]; unsigned long length; unsigned long addr; - int err; + char *err; if (kgdb_hex2long(&ptr, &addr) > 0 && *ptr++ == ',' && kgdb_hex2long(&ptr, &length) > 0) { err = kgdb_mem2hex((char *)addr, remcom_out_buffer, length); - if (err) - error_packet(remcom_out_buffer, err); + if (!err) + error_packet(remcom_out_buffer, -EINVAL); } else { error_packet(remcom_out_buffer, -EINVAL); } @@ -550,6 +572,60 @@ static void gdb_cmd_memwrite(struct kgdb_state *ks) strcpy(remcom_out_buffer, "OK"); } +#if DBG_MAX_REG_NUM > 0 +static char *gdb_hex_reg_helper(int regnum, char *out) +{ + int i; + int offset = 0; + + for (i = 0; i < regnum; i++) + offset += dbg_reg_def[i].size; + return kgdb_mem2hex((char *)gdb_regs + offset, out, + dbg_reg_def[i].size); +} + +/* Handle the 'p' individual regster get */ +static void gdb_cmd_reg_get(struct kgdb_state *ks) +{ + unsigned long regnum; + char *ptr = &remcom_in_buffer[1]; + + kgdb_hex2long(&ptr, ®num); + if (regnum >= DBG_MAX_REG_NUM) { + error_packet(remcom_out_buffer, -EINVAL); + return; + } + gdb_get_regs_helper(ks); + gdb_hex_reg_helper(regnum, remcom_out_buffer); +} + +/* Handle the 'P' individual regster set */ +static void gdb_cmd_reg_set(struct kgdb_state *ks) +{ + unsigned long regnum; + char *ptr = &remcom_in_buffer[1]; + int i = 0; + + kgdb_hex2long(&ptr, ®num); + if (*ptr++ != '=' || + !(!kgdb_usethread || kgdb_usethread == current) || + !dbg_get_reg(regnum, gdb_regs, ks->linux_regs)) { + error_packet(remcom_out_buffer, -EINVAL); + return; + } + memset(gdb_regs, 0, sizeof(gdb_regs)); + while (i < sizeof(gdb_regs) * 2) + if (hex_to_bin(ptr[i]) >= 0) + i++; + else + break; + i = i / 2; + kgdb_hex2mem(ptr, (char *)gdb_regs, i); + dbg_set_reg(regnum, gdb_regs, ks->linux_regs); + strcpy(remcom_out_buffer, "OK"); +} +#endif /* DBG_MAX_REG_NUM > 0 */ + /* Handle the 'X' memory binary write bytes */ static void gdb_cmd_binwrite(struct kgdb_state *ks) { @@ -612,7 +688,7 @@ static void gdb_cmd_query(struct kgdb_state *ks) { struct task_struct *g; struct task_struct *p; - unsigned char thref[8]; + unsigned char thref[BUF_THREAD_ID_SIZE]; char *ptr; int i; int cpu; @@ -632,8 +708,7 @@ static void gdb_cmd_query(struct kgdb_state *ks) for_each_online_cpu(cpu) { ks->thr_query = 0; int_to_threadref(thref, -cpu - 2); - pack_threadid(ptr, thref); - ptr += BUF_THREAD_ID_SIZE; + ptr = pack_threadid(ptr, thref); *(ptr++) = ','; i++; } @@ -642,8 +717,7 @@ static void gdb_cmd_query(struct kgdb_state *ks) do_each_thread(g, p) { if (i >= ks->thr_query && !finished) { int_to_threadref(thref, p->pid); - pack_threadid(ptr, thref); - ptr += BUF_THREAD_ID_SIZE; + ptr = pack_threadid(ptr, thref); *(ptr++) = ','; ks->thr_query++; if (ks->thr_query % KGDB_MAX_THREAD_QUERY == 0) @@ -858,11 +932,14 @@ int gdb_serial_stub(struct kgdb_state *ks) int error = 0; int tmp; - /* Clear the out buffer. */ + /* Initialize comm buffer and globals. */ memset(remcom_out_buffer, 0, sizeof(remcom_out_buffer)); + kgdb_usethread = kgdb_info[ks->cpu].task; + ks->kgdb_usethreadid = shadow_pid(kgdb_info[ks->cpu].task->pid); + ks->pass_exception = 0; if (kgdb_connected) { - unsigned char thref[8]; + unsigned char thref[BUF_THREAD_ID_SIZE]; char *ptr; /* Reply to host that an exception has occurred */ @@ -876,10 +953,6 @@ int gdb_serial_stub(struct kgdb_state *ks) put_packet(remcom_out_buffer); } - kgdb_usethread = kgdb_info[ks->cpu].task; - ks->kgdb_usethreadid = shadow_pid(kgdb_info[ks->cpu].task->pid); - ks->pass_exception = 0; - while (1) { error = 0; @@ -904,6 +977,14 @@ int gdb_serial_stub(struct kgdb_state *ks) case 'M': /* MAA..AA,LLLL: Write LLLL bytes at address AA..AA */ gdb_cmd_memwrite(ks); break; +#if DBG_MAX_REG_NUM > 0 + case 'p': /* pXX Return gdb register XX (in hex) */ + gdb_cmd_reg_get(ks); + break; + case 'P': /* PXX=aaaa Set gdb register XX to aaaa (in hex) */ + gdb_cmd_reg_set(ks); + break; +#endif /* DBG_MAX_REG_NUM > 0 */ case 'X': /* XAA..AA,LLLL: Write LLLL bytes at address AA..AA */ gdb_cmd_binwrite(ks); break; diff --git a/kernel/debug/kdb/kdb_main.c b/kernel/debug/kdb/kdb_main.c index ebe4a287419e..8577e45a9a58 100644 --- a/kernel/debug/kdb/kdb_main.c +++ b/kernel/debug/kdb/kdb_main.c @@ -312,7 +312,7 @@ int kdbgetularg(const char *arg, unsigned long *value) if (endp == arg) { /* - * Try base 16, for us folks too lazy to type the + * Also try base 16, for us folks too lazy to type the * leading 0x... */ val = simple_strtoul(arg, &endp, 16); @@ -325,6 +325,25 @@ int kdbgetularg(const char *arg, unsigned long *value) return 0; } +int kdbgetu64arg(const char *arg, u64 *value) +{ + char *endp; + u64 val; + + val = simple_strtoull(arg, &endp, 0); + + if (endp == arg) { + + val = simple_strtoull(arg, &endp, 16); + if (endp == arg) + return KDB_BADINT; + } + + *value = val; + + return 0; +} + /* * kdb_set - This function implements the 'set' command. Alter an * existing environment variable or create a new one. @@ -1770,11 +1789,65 @@ static int kdb_go(int argc, const char **argv) */ static int kdb_rd(int argc, const char **argv) { - int diag = kdb_check_regs(); - if (diag) - return diag; + int len = kdb_check_regs(); +#if DBG_MAX_REG_NUM > 0 + int i; + char *rname; + int rsize; + u64 reg64; + u32 reg32; + u16 reg16; + u8 reg8; + + if (len) + return len; + + for (i = 0; i < DBG_MAX_REG_NUM; i++) { + rsize = dbg_reg_def[i].size * 2; + if (rsize > 16) + rsize = 2; + if (len + strlen(dbg_reg_def[i].name) + 4 + rsize > 80) { + len = 0; + kdb_printf("\n"); + } + if (len) + len += kdb_printf(" "); + switch(dbg_reg_def[i].size * 8) { + case 8: + rname = dbg_get_reg(i, ®8, kdb_current_regs); + if (!rname) + break; + len += kdb_printf("%s: %02x", rname, reg8); + break; + case 16: + rname = dbg_get_reg(i, ®16, kdb_current_regs); + if (!rname) + break; + len += kdb_printf("%s: %04x", rname, reg16); + break; + case 32: + rname = dbg_get_reg(i, ®32, kdb_current_regs); + if (!rname) + break; + len += kdb_printf("%s: %08x", rname, reg32); + break; + case 64: + rname = dbg_get_reg(i, ®64, kdb_current_regs); + if (!rname) + break; + len += kdb_printf("%s: %016llx", rname, reg64); + break; + default: + len += kdb_printf("%s: ??", dbg_reg_def[i].name); + } + } + kdb_printf("\n"); +#else + if (len) + return len; kdb_dumpregs(kdb_current_regs); +#endif return 0; } @@ -1782,32 +1855,67 @@ static int kdb_rd(int argc, const char **argv) * kdb_rm - This function implements the 'rm' (register modify) command. * rm register-name new-contents * Remarks: - * Currently doesn't allow modification of control or - * debug registers. + * Allows register modification with the same restrictions as gdb */ static int kdb_rm(int argc, const char **argv) { +#if DBG_MAX_REG_NUM > 0 int diag; - int ind = 0; - unsigned long contents; + const char *rname; + int i; + u64 reg64; + u32 reg32; + u16 reg16; + u8 reg8; if (argc != 2) return KDB_ARGCOUNT; /* * Allow presence or absence of leading '%' symbol. */ - if (argv[1][0] == '%') - ind = 1; + rname = argv[1]; + if (*rname == '%') + rname++; - diag = kdbgetularg(argv[2], &contents); + diag = kdbgetu64arg(argv[2], ®64); if (diag) return diag; diag = kdb_check_regs(); if (diag) return diag; + + diag = KDB_BADREG; + for (i = 0; i < DBG_MAX_REG_NUM; i++) { + if (strcmp(rname, dbg_reg_def[i].name) == 0) { + diag = 0; + break; + } + } + if (!diag) { + switch(dbg_reg_def[i].size * 8) { + case 8: + reg8 = reg64; + dbg_set_reg(i, ®8, kdb_current_regs); + break; + case 16: + reg16 = reg64; + dbg_set_reg(i, ®16, kdb_current_regs); + break; + case 32: + reg32 = reg64; + dbg_set_reg(i, ®32, kdb_current_regs); + break; + case 64: + dbg_set_reg(i, ®64, kdb_current_regs); + break; + } + } + return diag; +#else kdb_printf("ERROR: Register set currently not implemented\n"); - return 0; + return 0; +#endif } #if defined(CONFIG_MAGIC_SYSRQ) diff --git a/kernel/trace/Makefile b/kernel/trace/Makefile index ffb1a5b0550e..4215530b490b 100644 --- a/kernel/trace/Makefile +++ b/kernel/trace/Makefile @@ -57,5 +57,8 @@ obj-$(CONFIG_EVENT_TRACING) += trace_events_filter.o obj-$(CONFIG_KPROBE_EVENT) += trace_kprobe.o obj-$(CONFIG_KSYM_TRACER) += trace_ksym.o obj-$(CONFIG_EVENT_TRACING) += power-traces.o +ifeq ($(CONFIG_TRACING),y) +obj-$(CONFIG_KGDB_KDB) += trace_kdb.o +endif libftrace-y := ftrace.o diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index 086d36316805..d6736b93dc2a 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -101,10 +101,7 @@ static inline void ftrace_enable_cpu(void) preempt_enable(); } -static cpumask_var_t __read_mostly tracing_buffer_mask; - -#define for_each_tracing_cpu(cpu) \ - for_each_cpu(cpu, tracing_buffer_mask) +cpumask_var_t __read_mostly tracing_buffer_mask; /* * ftrace_dump_on_oops - variable to dump ftrace buffer on oops @@ -1539,11 +1536,6 @@ int trace_vprintk(unsigned long ip, const char *fmt, va_list args) } EXPORT_SYMBOL_GPL(trace_vprintk); -enum trace_file_type { - TRACE_FILE_LAT_FMT = 1, - TRACE_FILE_ANNOTATE = 2, -}; - static void trace_iterator_increment(struct trace_iterator *iter) { /* Don't allow ftrace to trace into the ring buffers */ @@ -1641,7 +1633,7 @@ struct trace_entry *trace_find_next_entry(struct trace_iterator *iter, } /* Find the next real entry, and increment the iterator to the next entry */ -static void *find_next_entry_inc(struct trace_iterator *iter) +void *trace_find_next_entry_inc(struct trace_iterator *iter) { iter->ent = __find_next_entry(iter, &iter->cpu, &iter->lost_events, &iter->ts); @@ -1676,19 +1668,19 @@ static void *s_next(struct seq_file *m, void *v, loff_t *pos) return NULL; if (iter->idx < 0) - ent = find_next_entry_inc(iter); + ent = trace_find_next_entry_inc(iter); else ent = iter; while (ent && iter->idx < i) - ent = find_next_entry_inc(iter); + ent = trace_find_next_entry_inc(iter); iter->pos = *pos; return ent; } -static void tracing_iter_reset(struct trace_iterator *iter, int cpu) +void tracing_iter_reset(struct trace_iterator *iter, int cpu) { struct trace_array *tr = iter->tr; struct ring_buffer_event *event; @@ -2049,7 +2041,7 @@ int trace_empty(struct trace_iterator *iter) } /* Called with trace_event_read_lock() held. */ -static enum print_line_t print_trace_line(struct trace_iterator *iter) +enum print_line_t print_trace_line(struct trace_iterator *iter) { enum print_line_t ret; @@ -3211,7 +3203,7 @@ waitagain: trace_event_read_lock(); trace_access_lock(iter->cpu_file); - while (find_next_entry_inc(iter) != NULL) { + while (trace_find_next_entry_inc(iter) != NULL) { enum print_line_t ret; int len = iter->seq.len; @@ -3294,7 +3286,7 @@ tracing_fill_pipe_page(size_t rem, struct trace_iterator *iter) if (ret != TRACE_TYPE_NO_CONSUME) trace_consume(iter); rem -= count; - if (!find_next_entry_inc(iter)) { + if (!trace_find_next_entry_inc(iter)) { rem = 0; iter->ent = NULL; break; @@ -3350,7 +3342,7 @@ static ssize_t tracing_splice_read_pipe(struct file *filp, if (ret <= 0) goto out_err; - if (!iter->ent && !find_next_entry_inc(iter)) { + if (!iter->ent && !trace_find_next_entry_inc(iter)) { ret = -EFAULT; goto out_err; } @@ -4414,7 +4406,7 @@ static struct notifier_block trace_die_notifier = { */ #define KERN_TRACE KERN_EMERG -static void +void trace_printk_seq(struct trace_seq *s) { /* Probably should print a warning here. */ @@ -4429,6 +4421,13 @@ trace_printk_seq(struct trace_seq *s) trace_seq_init(s); } +void trace_init_global_iter(struct trace_iterator *iter) +{ + iter->tr = &global_trace; + iter->trace = current_trace; + iter->cpu_file = TRACE_PIPE_ALL_CPU; +} + static void __ftrace_dump(bool disable_tracing, enum ftrace_dump_mode oops_dump_mode) { @@ -4454,8 +4453,10 @@ __ftrace_dump(bool disable_tracing, enum ftrace_dump_mode oops_dump_mode) if (disable_tracing) ftrace_kill(); + trace_init_global_iter(&iter); + for_each_tracing_cpu(cpu) { - atomic_inc(&global_trace.data[cpu]->disabled); + atomic_inc(&iter.tr->data[cpu]->disabled); } old_userobj = trace_flags & TRACE_ITER_SYM_USEROBJ; @@ -4504,7 +4505,7 @@ __ftrace_dump(bool disable_tracing, enum ftrace_dump_mode oops_dump_mode) iter.iter_flags |= TRACE_FILE_LAT_FMT; iter.pos = -1; - if (find_next_entry_inc(&iter) != NULL) { + if (trace_find_next_entry_inc(&iter) != NULL) { int ret; ret = print_trace_line(&iter); @@ -4526,7 +4527,7 @@ __ftrace_dump(bool disable_tracing, enum ftrace_dump_mode oops_dump_mode) trace_flags |= old_userobj; for_each_tracing_cpu(cpu) { - atomic_dec(&global_trace.data[cpu]->disabled); + atomic_dec(&iter.tr->data[cpu]->disabled); } tracing_on(); } diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h index 2cd96399463f..0605fc00c176 100644 --- a/kernel/trace/trace.h +++ b/kernel/trace/trace.h @@ -338,6 +338,14 @@ struct trace_entry *tracing_get_trace_entry(struct trace_array *tr, struct trace_entry *trace_find_next_entry(struct trace_iterator *iter, int *ent_cpu, u64 *ent_ts); +int trace_empty(struct trace_iterator *iter); + +void *trace_find_next_entry_inc(struct trace_iterator *iter); + +void trace_init_global_iter(struct trace_iterator *iter); + +void tracing_iter_reset(struct trace_iterator *iter, int cpu); + void default_wait_pipe(struct trace_iterator *iter); void poll_wait_pipe(struct trace_iterator *iter); @@ -380,6 +388,15 @@ void tracing_start_sched_switch_record(void); int register_tracer(struct tracer *type); void unregister_tracer(struct tracer *type); int is_tracing_stopped(void); +enum trace_file_type { + TRACE_FILE_LAT_FMT = 1, + TRACE_FILE_ANNOTATE = 2, +}; + +extern cpumask_var_t __read_mostly tracing_buffer_mask; + +#define for_each_tracing_cpu(cpu) \ + for_each_cpu(cpu, tracing_buffer_mask) extern int process_new_ksym_entry(char *ksymname, int op, unsigned long addr); @@ -471,6 +488,8 @@ trace_array_vprintk(struct trace_array *tr, unsigned long ip, const char *fmt, va_list args); int trace_array_printk(struct trace_array *tr, unsigned long ip, const char *fmt, ...); +void trace_printk_seq(struct trace_seq *s); +enum print_line_t print_trace_line(struct trace_iterator *iter); extern unsigned long trace_flags; diff --git a/kernel/trace/trace_kdb.c b/kernel/trace/trace_kdb.c new file mode 100644 index 000000000000..7b8ecd751d93 --- /dev/null +++ b/kernel/trace/trace_kdb.c @@ -0,0 +1,136 @@ +/* + * kdb helper for dumping the ftrace buffer + * + * Copyright (C) 2010 Jason Wessel <jason.wessel@windriver.com> + * + * ftrace_dump_buf based on ftrace_dump: + * Copyright (C) 2007-2008 Steven Rostedt <srostedt@redhat.com> + * Copyright (C) 2008 Ingo Molnar <mingo@redhat.com> + * + */ +#include <linux/init.h> +#include <linux/kgdb.h> +#include <linux/kdb.h> +#include <linux/ftrace.h> + +#include "../debug/kdb/kdb_private.h" +#include "trace.h" +#include "trace_output.h" + +static void ftrace_dump_buf(int skip_lines, long cpu_file) +{ + /* use static because iter can be a bit big for the stack */ + static struct trace_iterator iter; + unsigned int old_userobj; + int cnt = 0, cpu; + + trace_init_global_iter(&iter); + + for_each_tracing_cpu(cpu) { + atomic_inc(&iter.tr->data[cpu]->disabled); + } + + old_userobj = trace_flags; + + /* don't look at user memory in panic mode */ + trace_flags &= ~TRACE_ITER_SYM_USEROBJ; + + kdb_printf("Dumping ftrace buffer:\n"); + + /* reset all but tr, trace, and overruns */ + memset(&iter.seq, 0, + sizeof(struct trace_iterator) - + offsetof(struct trace_iterator, seq)); + iter.iter_flags |= TRACE_FILE_LAT_FMT; + iter.pos = -1; + + if (cpu_file == TRACE_PIPE_ALL_CPU) { + for_each_tracing_cpu(cpu) { + iter.buffer_iter[cpu] = + ring_buffer_read_prepare(iter.tr->buffer, cpu); + ring_buffer_read_start(iter.buffer_iter[cpu]); + tracing_iter_reset(&iter, cpu); + } + } else { + iter.cpu_file = cpu_file; + iter.buffer_iter[cpu_file] = + ring_buffer_read_prepare(iter.tr->buffer, cpu_file); + ring_buffer_read_start(iter.buffer_iter[cpu_file]); + tracing_iter_reset(&iter, cpu_file); + } + if (!trace_empty(&iter)) + trace_find_next_entry_inc(&iter); + while (!trace_empty(&iter)) { + if (!cnt) + kdb_printf("---------------------------------\n"); + cnt++; + + if (trace_find_next_entry_inc(&iter) != NULL && !skip_lines) + print_trace_line(&iter); + if (!skip_lines) + trace_printk_seq(&iter.seq); + else + skip_lines--; + if (KDB_FLAG(CMD_INTERRUPT)) + goto out; + } + + if (!cnt) + kdb_printf(" (ftrace buffer empty)\n"); + else + kdb_printf("---------------------------------\n"); + +out: + trace_flags = old_userobj; + + for_each_tracing_cpu(cpu) { + atomic_dec(&iter.tr->data[cpu]->disabled); + } + + for_each_tracing_cpu(cpu) + if (iter.buffer_iter[cpu]) + ring_buffer_read_finish(iter.buffer_iter[cpu]); +} + +/* + * kdb_ftdump - Dump the ftrace log buffer + */ +static int kdb_ftdump(int argc, const char **argv) +{ + int skip_lines = 0; + long cpu_file; + char *cp; + + if (argc > 2) + return KDB_ARGCOUNT; + + if (argc) { + skip_lines = simple_strtol(argv[1], &cp, 0); + if (*cp) + skip_lines = 0; + } + + if (argc == 2) { + cpu_file = simple_strtol(argv[2], &cp, 0); + if (*cp || cpu_file >= NR_CPUS || cpu_file < 0 || + !cpu_online(cpu_file)) + return KDB_BADINT; + } else { + cpu_file = TRACE_PIPE_ALL_CPU; + } + + kdb_trap_printk++; + ftrace_dump_buf(skip_lines, cpu_file); + kdb_trap_printk--; + + return 0; +} + +static __init int kdb_ftrace_register(void) +{ + kdb_register_repeat("ftdump", kdb_ftdump, "[skip_#lines] [cpu]", + "Dump ftrace log", 0, KDB_REPEAT_NONE); + return 0; +} + +late_initcall(kdb_ftrace_register); |