diff options
Diffstat (limited to 'kernel')
-rw-r--r-- | kernel/debug/debug_core.c | 65 | ||||
-rw-r--r-- | kernel/debug/debug_core.h | 1 | ||||
-rw-r--r-- | kernel/debug/kdb/kdb_bt.c | 11 | ||||
-rw-r--r-- | kernel/debug/kdb/kdb_debugger.c | 7 | ||||
-rw-r--r-- | kernel/debug/kdb/kdb_main.c | 14 |
5 files changed, 82 insertions, 16 deletions
diff --git a/kernel/debug/debug_core.c b/kernel/debug/debug_core.c index 65c0f1363788..5cc608de6883 100644 --- a/kernel/debug/debug_core.c +++ b/kernel/debug/debug_core.c @@ -55,6 +55,7 @@ #include <linux/mm.h> #include <linux/vmacache.h> #include <linux/rcupdate.h> +#include <linux/irq.h> #include <asm/cacheflush.h> #include <asm/byteorder.h> @@ -220,6 +221,62 @@ int __weak kgdb_skipexception(int exception, struct pt_regs *regs) return 0; } +#ifdef CONFIG_SMP + +/* + * Default (weak) implementation for kgdb_roundup_cpus + */ + +static DEFINE_PER_CPU(call_single_data_t, kgdb_roundup_csd); + +void __weak kgdb_call_nmi_hook(void *ignored) +{ + /* + * NOTE: get_irq_regs() is supposed to get the registers from + * before the IPI interrupt happened and so is supposed to + * show where the processor was. In some situations it's + * possible we might be called without an IPI, so it might be + * safer to figure out how to make kgdb_breakpoint() work + * properly here. + */ + kgdb_nmicallback(raw_smp_processor_id(), get_irq_regs()); +} + +void __weak kgdb_roundup_cpus(void) +{ + call_single_data_t *csd; + int this_cpu = raw_smp_processor_id(); + int cpu; + int ret; + + for_each_online_cpu(cpu) { + /* No need to roundup ourselves */ + if (cpu == this_cpu) + continue; + + csd = &per_cpu(kgdb_roundup_csd, cpu); + + /* + * If it didn't round up last time, don't try again + * since smp_call_function_single_async() will block. + * + * If rounding_up is false then we know that the + * previous call must have at least started and that + * means smp_call_function_single_async() won't block. + */ + if (kgdb_info[cpu].rounding_up) + continue; + kgdb_info[cpu].rounding_up = true; + + csd->func = kgdb_call_nmi_hook; + ret = smp_call_function_single_async(cpu, csd); + if (ret) + kgdb_info[cpu].rounding_up = false; + } +} + +#endif + /* * Some architectures need cache flushes when we set/clear a * breakpoint: @@ -535,6 +592,8 @@ return_normal: arch_kgdb_ops.correct_hw_break(); if (trace_on) tracing_on(); + kgdb_info[cpu].debuggerinfo = NULL; + kgdb_info[cpu].task = NULL; kgdb_info[cpu].exception_state &= ~(DCPU_WANT_MASTER | DCPU_IS_SLAVE); kgdb_info[cpu].enter_kgdb--; @@ -593,7 +652,7 @@ return_normal: /* Signal the other CPUs to enter kgdb_wait() */ else if ((!kgdb_single_step) && kgdb_do_roundup) - kgdb_roundup_cpus(flags); + kgdb_roundup_cpus(); #endif /* @@ -667,6 +726,8 @@ kgdb_restore: if (trace_on) tracing_on(); + kgdb_info[cpu].debuggerinfo = NULL; + kgdb_info[cpu].task = NULL; kgdb_info[cpu].exception_state &= ~(DCPU_WANT_MASTER | DCPU_IS_SLAVE); kgdb_info[cpu].enter_kgdb--; @@ -747,6 +808,8 @@ int kgdb_nmicallback(int cpu, void *regs) struct kgdb_state kgdb_var; struct kgdb_state *ks = &kgdb_var; + kgdb_info[cpu].rounding_up = false; + memset(ks, 0, sizeof(struct kgdb_state)); ks->cpu = cpu; ks->linux_regs = regs; diff --git a/kernel/debug/debug_core.h b/kernel/debug/debug_core.h index 127d9bc49fb4..b4a7c326d546 100644 --- a/kernel/debug/debug_core.h +++ b/kernel/debug/debug_core.h @@ -42,6 +42,7 @@ struct debuggerinfo_struct { int ret_state; int irq_depth; int enter_kgdb; + bool rounding_up; }; extern struct debuggerinfo_struct kgdb_info[]; diff --git a/kernel/debug/kdb/kdb_bt.c b/kernel/debug/kdb/kdb_bt.c index 7921ae4fca8d..7e2379aa0a1e 100644 --- a/kernel/debug/kdb/kdb_bt.c +++ b/kernel/debug/kdb/kdb_bt.c @@ -186,7 +186,16 @@ kdb_bt(int argc, const char **argv) kdb_printf("btc: cpu status: "); kdb_parse("cpu\n"); for_each_online_cpu(cpu) { - sprintf(buf, "btt 0x%px\n", KDB_TSK(cpu)); + void *kdb_tsk = KDB_TSK(cpu); + + /* If a CPU failed to round up we could be here */ + if (!kdb_tsk) { + kdb_printf("WARNING: no task for cpu %ld\n", + cpu); + continue; + } + + sprintf(buf, "btt 0x%px\n", kdb_tsk); kdb_parse(buf); touch_nmi_watchdog(); } diff --git a/kernel/debug/kdb/kdb_debugger.c b/kernel/debug/kdb/kdb_debugger.c index 15e1a7af5dd0..53a0df6e4d92 100644 --- a/kernel/debug/kdb/kdb_debugger.c +++ b/kernel/debug/kdb/kdb_debugger.c @@ -118,13 +118,6 @@ int kdb_stub(struct kgdb_state *ks) kdb_bp_remove(); KDB_STATE_CLEAR(DOING_SS); KDB_STATE_SET(PAGER); - /* zero out any offline cpu data */ - for_each_present_cpu(i) { - if (!cpu_online(i)) { - kgdb_info[i].debuggerinfo = NULL; - kgdb_info[i].task = NULL; - } - } if (ks->err_code == DIE_OOPS || reason == KDB_REASON_OOPS) { ks->pass_exception = 1; KDB_FLAG_SET(CATASTROPHIC); diff --git a/kernel/debug/kdb/kdb_main.c b/kernel/debug/kdb/kdb_main.c index d72b32c66f7d..82a3b32a7cfc 100644 --- a/kernel/debug/kdb/kdb_main.c +++ b/kernel/debug/kdb/kdb_main.c @@ -658,7 +658,7 @@ static void kdb_cmderror(int diag) */ struct defcmd_set { int count; - int usable; + bool usable; char *name; char *usage; char *help; @@ -666,7 +666,7 @@ struct defcmd_set { }; static struct defcmd_set *defcmd_set; static int defcmd_set_count; -static int defcmd_in_progress; +static bool defcmd_in_progress; /* Forward references */ static int kdb_exec_defcmd(int argc, const char **argv); @@ -676,9 +676,9 @@ static int kdb_defcmd2(const char *cmdstr, const char *argv0) struct defcmd_set *s = defcmd_set + defcmd_set_count - 1; char **save_command = s->command; if (strcmp(argv0, "endefcmd") == 0) { - defcmd_in_progress = 0; + defcmd_in_progress = false; if (!s->count) - s->usable = 0; + s->usable = false; if (s->usable) /* macros are always safe because when executed each * internal command re-enters kdb_parse() and is @@ -695,7 +695,7 @@ static int kdb_defcmd2(const char *cmdstr, const char *argv0) if (!s->command) { kdb_printf("Could not allocate new kdb_defcmd table for %s\n", cmdstr); - s->usable = 0; + s->usable = false; return KDB_NOTIMP; } memcpy(s->command, save_command, s->count * sizeof(*(s->command))); @@ -737,7 +737,7 @@ static int kdb_defcmd(int argc, const char **argv) defcmd_set_count * sizeof(*defcmd_set)); s = defcmd_set + defcmd_set_count; memset(s, 0, sizeof(*s)); - s->usable = 1; + s->usable = true; s->name = kdb_strdup(argv[1], GFP_KDB); if (!s->name) goto fail_name; @@ -756,7 +756,7 @@ static int kdb_defcmd(int argc, const char **argv) s->help[strlen(s->help)-1] = '\0'; } ++defcmd_set_count; - defcmd_in_progress = 1; + defcmd_in_progress = true; kfree(save_defcmd_set); return 0; fail_help: |