From 931ea24819f2bd40cca2dc214558bfcc3c91549e Mon Sep 17 00:00:00 2001 From: Jason Wessel Date: Fri, 29 Oct 2010 08:04:16 -0500 Subject: kdb: fix per_cpu command to remove supress mask Rusty pointed out that the per_cpu command uses up lots of space on the stack and the cpu supress mask is probably not needed. This patch removes the need for the supress mask as well as fixing up the following problems with the kdb per_cpu command: * The per_cpu command should allow an address as an argument * When you have more data than can be displayed on one screen allow the user to break out of the print loop. Reported-by: Rusty Russell Signed-off-by: Jason Wessel --- kernel/debug/kdb/kdb_main.c | 46 +++++++++++---------------------------------- 1 file changed, 11 insertions(+), 35 deletions(-) (limited to 'kernel') diff --git a/kernel/debug/kdb/kdb_main.c b/kernel/debug/kdb/kdb_main.c index d7bda21..9755ac0 100644 --- a/kernel/debug/kdb/kdb_main.c +++ b/kernel/debug/kdb/kdb_main.c @@ -2603,20 +2603,17 @@ static int kdb_summary(int argc, const char **argv) */ static int kdb_per_cpu(int argc, const char **argv) { - char buf[256], fmtstr[64]; - kdb_symtab_t symtab; - cpumask_t suppress = CPU_MASK_NONE; - int cpu, diag; - unsigned long addr, val, bytesperword = 0, whichcpu = ~0UL; + char fmtstr[64]; + int cpu, diag, nextarg = 1; + unsigned long addr, symaddr, val, bytesperword = 0, whichcpu = ~0UL; if (argc < 1 || argc > 3) return KDB_ARGCOUNT; - snprintf(buf, sizeof(buf), "per_cpu__%s", argv[1]); - if (!kdbgetsymval(buf, &symtab)) { - kdb_printf("%s is not a per_cpu variable\n", argv[1]); - return KDB_BADADDR; - } + diag = kdbgetaddrarg(argc, argv, &nextarg, &symaddr, NULL, NULL); + if (diag) + return diag; + if (argc >= 2) { diag = kdbgetularg(argv[2], &bytesperword); if (diag) @@ -2649,46 +2646,25 @@ static int kdb_per_cpu(int argc, const char **argv) #define KDB_PCU(cpu) 0 #endif #endif - for_each_online_cpu(cpu) { + if (KDB_FLAG(CMD_INTERRUPT)) + return 0; + if (whichcpu != ~0UL && whichcpu != cpu) continue; - addr = symtab.sym_start + KDB_PCU(cpu); + addr = symaddr + KDB_PCU(cpu); diag = kdb_getword(&val, addr, bytesperword); if (diag) { kdb_printf("%5d " kdb_bfd_vma_fmt0 " - unable to " "read, diag=%d\n", cpu, addr, diag); continue; } -#ifdef CONFIG_SMP - if (!val) { - cpu_set(cpu, suppress); - continue; - } -#endif /* CONFIG_SMP */ kdb_printf("%5d ", cpu); kdb_md_line(fmtstr, addr, bytesperword == KDB_WORD_SIZE, 1, bytesperword, 1, 1, 0); } - if (cpus_weight(suppress) == 0) - return 0; - kdb_printf("Zero suppressed cpu(s):"); - for (cpu = first_cpu(suppress); cpu < num_possible_cpus(); - cpu = next_cpu(cpu, suppress)) { - kdb_printf(" %d", cpu); - if (cpu == num_possible_cpus() - 1 || - next_cpu(cpu, suppress) != cpu + 1) - continue; - while (cpu < num_possible_cpus() && - next_cpu(cpu, suppress) == cpu + 1) - ++cpu; - kdb_printf("-%d", cpu); - } - kdb_printf("\n"); - #undef KDB_PCU - return 0; } -- cgit v1.1 From 578bd4dfcda63d2ef15f025f1d5d55c0e56b9660 Mon Sep 17 00:00:00 2001 From: Jason Wessel Date: Fri, 29 Oct 2010 13:14:41 -0500 Subject: kdb: Fix early debugging crash regression The kdb_current legally be equal to NULL in the early boot of the x86 arch. The problem pcan be observed by booting with the kernel arguments: earlyprintk=vga ekgdboc=kbd kgdbwait The kdb shell will oops on entry and recursively fault because it cannot get past the final stage of shell initialization. Signed-off-by: Jason Wessel --- kernel/debug/kdb/kdb_main.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'kernel') diff --git a/kernel/debug/kdb/kdb_main.c b/kernel/debug/kdb/kdb_main.c index 9755ac0..37755d6 100644 --- a/kernel/debug/kdb/kdb_main.c +++ b/kernel/debug/kdb/kdb_main.c @@ -1127,7 +1127,7 @@ static int kdb_local(kdb_reason_t reason, int error, struct pt_regs *regs, /* special case below */ } else { kdb_printf("\nEntering kdb (current=0x%p, pid %d) ", - kdb_current, kdb_current->pid); + kdb_current, kdb_current ? kdb_current->pid : 0); #if defined(CONFIG_SMP) kdb_printf("on processor %d ", raw_smp_processor_id()); #endif -- cgit v1.1 From d7ba979d45272385ce0fdf141d922e61ff48e07b Mon Sep 17 00:00:00 2001 From: Dongdong Deng Date: Wed, 18 Aug 2010 06:02:00 -0500 Subject: debug_core,x86,blackfin: Clean up hw debug disable API The kgdb_disable_hw_debug() was an architecture specific function for disabling all hardware breakpoints on a per cpu basis when entering the debug core. This patch will remove the weak function kdbg_disable_hw_debug() and change it into a call back which lives with the rest of hw breakpoint call backs in struct kgdb_arch. Signed-off-by: Dongdong Deng Signed-off-by: Jason Wessel --- kernel/debug/debug_core.c | 16 +++------------- 1 file changed, 3 insertions(+), 13 deletions(-) (limited to 'kernel') diff --git a/kernel/debug/debug_core.c b/kernel/debug/debug_core.c index fec596d..cefd4a1 100644 --- a/kernel/debug/debug_core.c +++ b/kernel/debug/debug_core.c @@ -209,18 +209,6 @@ int __weak kgdb_skipexception(int exception, struct pt_regs *regs) return 0; } -/** - * kgdb_disable_hw_debug - Disable hardware debugging while we in kgdb. - * @regs: Current &struct pt_regs. - * - * This function will be called if the particular architecture must - * disable hardware debugging while it is processing gdb packets or - * handling exception. - */ -void __weak kgdb_disable_hw_debug(struct pt_regs *regs) -{ -} - /* * Some architectures need cache flushes when we set/clear a * breakpoint: @@ -484,7 +472,9 @@ static int kgdb_cpu_enter(struct kgdb_state *ks, struct pt_regs *regs, atomic_inc(&masters_in_kgdb); else atomic_inc(&slaves_in_kgdb); - kgdb_disable_hw_debug(ks->linux_regs); + + if (arch_kgdb_ops.disable_hw_break) + arch_kgdb_ops.disable_hw_break(regs); acquirelock: /* -- cgit v1.1