diff options
Diffstat (limited to 'drivers/gator/gator_backtrace.c')
| -rw-r--r-- | drivers/gator/gator_backtrace.c | 66 |
1 files changed, 33 insertions, 33 deletions
diff --git a/drivers/gator/gator_backtrace.c b/drivers/gator/gator_backtrace.c index e03c1653c5b5..76c941d009a9 100644 --- a/drivers/gator/gator_backtrace.c +++ b/drivers/gator/gator_backtrace.c @@ -14,17 +14,17 @@ struct stack_frame_eabi { union { struct { unsigned long fp; - // May be the fp in the case of a leaf function or clang + /* May be the fp in the case of a leaf function or clang */ unsigned long lr; - // If lr is really the fp, lr2 is the corresponding lr + /* If lr is really the fp, lr2 is the corresponding lr */ unsigned long lr2; }; - // Used to read 32 bit fp/lr from a 64 bit kernel + /* Used to read 32 bit fp/lr from a 64 bit kernel */ struct { u32 fp_32; - // same as lr above + /* same as lr above */ u32 lr_32; - // same as lr2 above + /* same as lr2 above */ u32 lr2_32; }; }; @@ -35,9 +35,8 @@ static void gator_add_trace(int cpu, unsigned long address) off_t offset = 0; unsigned long cookie = get_address_cookie(cpu, current, address & ~1, &offset); - if (cookie == NO_COOKIE || cookie == UNRESOLVED_COOKIE) { + if (cookie == NO_COOKIE || cookie == UNRESOLVED_COOKIE) offset = address; - } marshal_backtrace(offset & ~1, cookie, 0); } @@ -54,36 +53,34 @@ static void arm_backtrace_eabi(int cpu, struct pt_regs *const regs, unsigned int unsigned long lr = regs->ARM_lr; const int gcc_frame_offset = sizeof(unsigned long); #else - // Is userspace aarch32 (32 bit) + /* Is userspace aarch32 (32 bit) */ const bool is_compat = compat_user_mode(regs); unsigned long fp = (is_compat ? regs->regs[11] : regs->regs[29]); unsigned long sp = (is_compat ? regs->compat_sp : regs->sp); unsigned long lr = (is_compat ? regs->compat_lr : regs->regs[30]); const int gcc_frame_offset = (is_compat ? sizeof(u32) : 0); #endif - // clang frame offset is always zero + /* clang frame offset is always zero */ int is_user_mode = user_mode(regs); - // pc (current function) has already been added + /* pc (current function) has already been added */ - if (!is_user_mode) { + if (!is_user_mode) return; - } - // Add the lr (parent function) - // entry preamble may not have executed + /* Add the lr (parent function), entry preamble may not have + * executed + */ gator_add_trace(cpu, lr); - // check fp is valid - if (fp == 0 || fp < sp) { + /* check fp is valid */ + if (fp == 0 || fp < sp) return; - } - // Get the current stack frame + /* Get the current stack frame */ curr = (struct stack_frame_eabi *)(fp - gcc_frame_offset); - if ((unsigned long)curr & 3) { + if ((unsigned long)curr & 3) return; - } while (depth-- && curr) { if (!access_ok(VERIFY_READ, curr, sizeof(struct stack_frame_eabi)) || @@ -95,13 +92,15 @@ static void arm_backtrace_eabi(int cpu, struct pt_regs *const regs, unsigned int lr = (is_compat ? bufcurr.lr_32 : bufcurr.lr); #define calc_next(reg) ((reg) - gcc_frame_offset) - // Returns true if reg is a valid fp + /* Returns true if reg is a valid fp */ #define validate_next(reg, curr) \ ((reg) != 0 && (calc_next(reg) & 3) == 0 && (unsigned long)(curr) < calc_next(reg)) - // Try lr from the stack as the fp because gcc leaf functions do not push lr - // If gcc_frame_offset is non-zero, the lr will also be the clang fp - // This assumes code is at a lower address than the stack + /* Try lr from the stack as the fp because gcc leaf functions do + * not push lr. If gcc_frame_offset is non-zero, the lr will also + * be the clang fp. This assumes code is at a lower address than + * the stack + */ if (validate_next(lr, curr)) { fp = lr; lr = (is_compat ? bufcurr.lr2_32 : bufcurr.lr2); @@ -109,11 +108,10 @@ static void arm_backtrace_eabi(int cpu, struct pt_regs *const regs, unsigned int gator_add_trace(cpu, lr); - if (!validate_next(fp, curr)) { + if (!validate_next(fp, curr)) return; - } - // Move to the next stack frame + /* Move to the next stack frame */ curr = (struct stack_frame_eabi *)calc_next(fp); } #endif @@ -129,6 +127,7 @@ static int report_trace(struct stackframe *frame, void *d) #if defined(MODULE) unsigned int cpu = get_physical_cpu(); struct module *mod = __module_address(addr); + if (mod) { cookie = get_cookie(cpu, current, mod->name, false); addr = addr - (unsigned long)mod->module_core; @@ -142,13 +141,13 @@ static int report_trace(struct stackframe *frame, void *d) } #endif -// Uncomment the following line to enable kernel stack unwinding within gator, note it can also be defined from the Makefile -// #define GATOR_KERNEL_STACK_UNWINDING +/* Uncomment the following line to enable kernel stack unwinding within gator, note it can also be defined from the Makefile */ +/* #define GATOR_KERNEL_STACK_UNWINDING */ #if (defined(__arm__) || defined(__aarch64__)) && !defined(GATOR_KERNEL_STACK_UNWINDING) -// Disabled by default +/* Disabled by default */ MODULE_PARM_DESC(kernel_stack_unwinding, "Allow kernel stack unwinding."); -static bool kernel_stack_unwinding = 0; +static bool kernel_stack_unwinding; module_param(kernel_stack_unwinding, bool, 0644); #endif @@ -161,6 +160,7 @@ static void kernel_backtrace(int cpu, struct pt_regs *const regs) int depth = (kernel_stack_unwinding ? gator_backtrace_depth : 1); #endif struct stackframe frame; + if (depth == 0) depth = 1; #if defined(__arm__) @@ -196,10 +196,10 @@ static void gator_add_sample(int cpu, struct pt_regs *const regs, u64 time) if (in_kernel) { kernel_backtrace(cpu, regs); } else { - // Cookie+PC + /* Cookie+PC */ gator_add_trace(cpu, PC_REG); - // Backtrace + /* Backtrace */ if (gator_backtrace_depth) arm_backtrace_eabi(cpu, regs, gator_backtrace_depth); } |