diff options
Diffstat (limited to 'kernel')
| -rw-r--r-- | kernel/exit.c | 5 | ||||
| -rw-r--r-- | kernel/hw_breakpoint.c | 424 | ||||
| -rw-r--r-- | kernel/perf_event.c | 53 | ||||
| -rw-r--r-- | kernel/trace/trace.h | 5 | ||||
| -rw-r--r-- | kernel/trace/trace_entries.h | 6 | ||||
| -rw-r--r-- | kernel/trace/trace_ksym.c | 126 | ||||
| -rw-r--r-- | kernel/trace/trace_selftest.c | 3 |
7 files changed, 293 insertions, 329 deletions
diff --git a/kernel/exit.c b/kernel/exit.c index e61891f..266f892 100644 --- a/kernel/exit.c +++ b/kernel/exit.c @@ -49,6 +49,7 @@ #include <linux/init_task.h> #include <linux/perf_event.h> #include <trace/events/sched.h> +#include <linux/hw_breakpoint.h> #include <asm/uaccess.h> #include <asm/unistd.h> @@ -980,6 +981,10 @@ NORET_TYPE void do_exit(long code) proc_exit_connector(tsk); /* + * FIXME: do that only when needed, using sched_exit tracepoint + */ + flush_ptrace_hw_breakpoint(tsk); + /* * Flush inherited counters to the parent - before the parent * gets woken up by child-exit notifications. */ diff --git a/kernel/hw_breakpoint.c b/kernel/hw_breakpoint.c index c1f64e6..08f6d01 100644 --- a/kernel/hw_breakpoint.c +++ b/kernel/hw_breakpoint.c @@ -15,6 +15,7 @@ * * Copyright (C) 2007 Alan Stern * Copyright (C) IBM Corporation, 2009 + * Copyright (C) 2009, Frederic Weisbecker <fweisbec@gmail.com> */ /* @@ -35,334 +36,242 @@ #include <linux/init.h> #include <linux/smp.h> -#include <asm/hw_breakpoint.h> +#include <linux/hw_breakpoint.h> + #include <asm/processor.h> #ifdef CONFIG_X86 #include <asm/debugreg.h> #endif -/* - * Spinlock that protects all (un)register operations over kernel/user-space - * breakpoint requests - */ -static DEFINE_SPINLOCK(hw_breakpoint_lock); - -/* Array of kernel-space breakpoint structures */ -struct hw_breakpoint *hbp_kernel[HBP_NUM]; - -/* - * Per-processor copy of hbp_kernel[]. Used only when hbp_kernel is being - * modified but we need the older copy to handle any hbp exceptions. It will - * sync with hbp_kernel[] value after updation is done through IPIs. - */ -DEFINE_PER_CPU(struct hw_breakpoint*, this_hbp_kernel[HBP_NUM]); - -/* - * Kernel breakpoints grow downwards, starting from HBP_NUM - * 'hbp_kernel_pos' denotes lowest numbered breakpoint register occupied for - * kernel-space request. We will initialise it here and not in an __init - * routine because load_debug_registers(), which uses this variable can be - * called very early during CPU initialisation. - */ -unsigned int hbp_kernel_pos = HBP_NUM; -/* - * An array containing refcount of threads using a given bkpt register - * Accesses are synchronised by acquiring hw_breakpoint_lock - */ -unsigned int hbp_user_refcount[HBP_NUM]; +static atomic_t bp_slot; -/* - * Load the debug registers during startup of a CPU. - */ -void load_debug_registers(void) +int reserve_bp_slot(struct perf_event *bp) { - unsigned long flags; - struct task_struct *tsk = current; - - spin_lock_bh(&hw_breakpoint_lock); - - /* Prevent IPIs for new kernel breakpoint updates */ - local_irq_save(flags); - arch_update_kernel_hw_breakpoint(NULL); - local_irq_restore(flags); - - if (test_tsk_thread_flag(tsk, TIF_DEBUG)) - arch_install_thread_hw_breakpoint(tsk); - - spin_unlock_bh(&hw_breakpoint_lock); -} + if (atomic_inc_return(&bp_slot) == HBP_NUM) { + atomic_dec(&bp_slot); -/* - * Erase all the hardware breakpoint info associated with a thread. - * - * If tsk != current then tsk must not be usable (for example, a - * child being cleaned up from a failed fork). - */ -void flush_thread_hw_breakpoint(struct task_struct *tsk) -{ - int i; - struct thread_struct *thread = &(tsk->thread); - - spin_lock_bh(&hw_breakpoint_lock); - - /* The thread no longer has any breakpoints associated with it */ - clear_tsk_thread_flag(tsk, TIF_DEBUG); - for (i = 0; i < HBP_NUM; i++) { - if (thread->hbp[i]) { - hbp_user_refcount[i]--; - kfree(thread->hbp[i]); - thread->hbp[i] = NULL; - } + return -ENOSPC; } - arch_flush_thread_hw_breakpoint(tsk); - - /* Actually uninstall the breakpoints if necessary */ - if (tsk == current) - arch_uninstall_thread_hw_breakpoint(); - spin_unlock_bh(&hw_breakpoint_lock); + return 0; } -/* - * Copy the hardware breakpoint info from a thread to its cloned child. - */ -int copy_thread_hw_breakpoint(struct task_struct *tsk, - struct task_struct *child, unsigned long clone_flags) +void release_bp_slot(struct perf_event *bp) { - /* - * We will assume that breakpoint settings are not inherited - * and the child starts out with no debug registers set. - * But what about CLONE_PTRACE? - */ - clear_tsk_thread_flag(child, TIF_DEBUG); - - /* We will call flush routine since the debugregs are not inherited */ - arch_flush_thread_hw_breakpoint(child); - - return 0; + atomic_dec(&bp_slot); } -static int __register_user_hw_breakpoint(int pos, struct task_struct *tsk, - struct hw_breakpoint *bp) +int __register_perf_hw_breakpoint(struct perf_event *bp) { - struct thread_struct *thread = &(tsk->thread); - int rc; + int ret; - /* Do not overcommit. Fail if kernel has used the hbp registers */ - if (pos >= hbp_kernel_pos) - return -ENOSPC; + ret = reserve_bp_slot(bp); + if (ret) + return ret; - rc = arch_validate_hwbkpt_settings(bp, tsk); - if (rc) - return rc; + if (!bp->attr.disabled) + ret = arch_validate_hwbkpt_settings(bp, bp->ctx->task); - thread->hbp[pos] = bp; - hbp_user_refcount[pos]++; + return ret; +} - arch_update_user_hw_breakpoint(pos, tsk); - /* - * Does it need to be installed right now? - * Otherwise it will get installed the next time tsk runs - */ - if (tsk == current) - arch_install_thread_hw_breakpoint(tsk); +int register_perf_hw_breakpoint(struct perf_event *bp) +{ + bp->callback = perf_bp_event; - return rc; + return __register_perf_hw_breakpoint(bp); } /* - * Modify the address of a hbp register already in use by the task - * Do not invoke this in-lieu of a __unregister_user_hw_breakpoint() + * Register a breakpoint bound to a task and a given cpu. + * If cpu is -1, the breakpoint is active for the task in every cpu + * If the task is -1, the breakpoint is active for every tasks in the given + * cpu. */ -static int __modify_user_hw_breakpoint(int pos, struct task_struct *tsk, - struct hw_breakpoint *bp) +static struct perf_event * +register_user_hw_breakpoint_cpu(unsigned long addr, + int len, + int type, + perf_callback_t triggered, + pid_t pid, + int cpu, + bool active) { - struct thread_struct *thread = &(tsk->thread); - - if ((pos >= hbp_kernel_pos) || (arch_validate_hwbkpt_settings(bp, tsk))) - return -EINVAL; - - if (thread->hbp[pos] == NULL) - return -EINVAL; - - thread->hbp[pos] = bp; + struct perf_event_attr *attr; + struct perf_event *bp; + + attr = kzalloc(sizeof(*attr), GFP_KERNEL); + if (!attr) + return ERR_PTR(-ENOMEM); + + attr->type = PERF_TYPE_BREAKPOINT; + attr->size = sizeof(*attr); + attr->bp_addr = addr; + attr->bp_len = len; + attr->bp_type = type; /* - * 'pos' must be that of a hbp register already used by 'tsk' - * Otherwise arch_modify_user_hw_breakpoint() will fail + * Such breakpoints are used by debuggers to trigger signals when + * we hit the excepted memory op. We can't miss such events, they + * must be pinned. */ - arch_update_user_hw_breakpoint(pos, tsk); + attr->pinned = 1; - if (tsk == current) - arch_install_thread_hw_breakpoint(tsk); + if (!active) + attr->disabled = 1; - return 0; -} - -static void __unregister_user_hw_breakpoint(int pos, struct task_struct *tsk) -{ - hbp_user_refcount[pos]--; - tsk->thread.hbp[pos] = NULL; + bp = perf_event_create_kernel_counter(attr, cpu, pid, triggered); + kfree(attr); - arch_update_user_hw_breakpoint(pos, tsk); - - if (tsk == current) - arch_install_thread_hw_breakpoint(tsk); + return bp; } /** * register_user_hw_breakpoint - register a hardware breakpoint for user space + * @addr: is the memory address that triggers the breakpoint + * @len: the length of the access to the memory (1 byte, 2 bytes etc...) + * @type: the type of the access to the memory (read/write/exec) + * @triggered: callback to trigger when we hit the breakpoint * @tsk: pointer to 'task_struct' of the process to which the address belongs - * @bp: the breakpoint structure to register - * - * @bp.info->name or @bp.info->address, @bp.info->len, @bp.info->type and - * @bp->triggered must be set properly before invocation + * @active: should we activate it while registering it * */ -int register_user_hw_breakpoint(struct task_struct *tsk, - struct hw_breakpoint *bp) +struct perf_event * +register_user_hw_breakpoint(unsigned long addr, + int len, + int type, + perf_callback_t triggered, + struct task_struct *tsk, + bool active) { - struct thread_struct *thread = &(tsk->thread); - int i, rc = -ENOSPC; - - spin_lock_bh(&hw_breakpoint_lock); - - for (i = 0; i < hbp_kernel_pos; i++) { - if (!thread->hbp[i]) { - rc = __register_user_hw_breakpoint(i, tsk, bp); - break; - } - } - if (!rc) - set_tsk_thread_flag(tsk, TIF_DEBUG); - - spin_unlock_bh(&hw_breakpoint_lock); - return rc; + return register_user_hw_breakpoint_cpu(addr, len, type, triggered, + tsk->pid, -1, active); } EXPORT_SYMBOL_GPL(register_user_hw_breakpoint); /** * modify_user_hw_breakpoint - modify a user-space hardware breakpoint + * @bp: the breakpoint structure to modify + * @addr: is the memory address that triggers the breakpoint + * @len: the length of the access to the memory (1 byte, 2 bytes etc...) + * @type: the type of the access to the memory (read/write/exec) + * @triggered: callback to trigger when we hit the breakpoint * @tsk: pointer to 'task_struct' of the process to which the address belongs - * @bp: the breakpoint structure to unregister - * + * @active: should we activate it while registering it */ -int modify_user_hw_breakpoint(struct task_struct *tsk, struct hw_breakpoint *bp) +struct perf_event * +modify_user_hw_breakpoint(struct perf_event *bp, + unsigned long addr, + int len, + int type, + perf_callback_t triggered, + struct task_struct *tsk, + bool active) { - struct thread_struct *thread = &(tsk->thread); - int i, ret = -ENOENT; + /* + * FIXME: do it without unregistering + * - We don't want to lose our slot + * - If the new bp is incorrect, don't lose the older one + */ + unregister_hw_breakpoint(bp); - spin_lock_bh(&hw_breakpoint_lock); - for (i = 0; i < hbp_kernel_pos; i++) { - if (bp == thread->hbp[i]) { - ret = __modify_user_hw_breakpoint(i, tsk, bp); - break; - } - } - spin_unlock_bh(&hw_breakpoint_lock); - return ret; + return register_user_hw_breakpoint(addr, len, type, triggered, + tsk, active); } EXPORT_SYMBOL_GPL(modify_user_hw_breakpoint); /** - * unregister_user_hw_breakpoint - unregister a user-space hardware breakpoint - * @tsk: pointer to 'task_struct' of the process to which the address belongs + * unregister_hw_breakpoint - unregister a user-space hardware breakpoint * @bp: the breakpoint structure to unregister - * */ -void unregister_user_hw_breakpoint(struct task_struct *tsk, - struct hw_breakpoint *bp) +void unregister_hw_breakpoint(struct perf_event *bp) { - struct thread_struct *thread = &(tsk->thread); - int i, pos = -1, hbp_counter = 0; - - spin_lock_bh(&hw_breakpoint_lock); - for (i = 0; i < hbp_kernel_pos; i++) { - if (thread->hbp[i]) - hbp_counter++; - if (bp == thread->hbp[i]) - pos = i; - } - if (pos >= 0) { - __unregister_user_hw_breakpoint(pos, tsk); - hbp_counter--; - } - if (!hbp_counter) - clear_tsk_thread_flag(tsk, TIF_DEBUG); - - spin_unlock_bh(&hw_breakpoint_lock); + if (!bp) + return; + perf_event_release_kernel(bp); +} +EXPORT_SYMBOL_GPL(unregister_hw_breakpoint); + +static struct perf_event * +register_kernel_hw_breakpoint_cpu(unsigned long addr, + int len, + int type, + perf_callback_t triggered, + int cpu, + bool active) +{ + return register_user_hw_breakpoint_cpu(addr, len, type, triggered, + -1, cpu, active); } -EXPORT_SYMBOL_GPL(unregister_user_hw_breakpoint); /** - * register_kernel_hw_breakpoint - register a hardware breakpoint for kernel space - * @bp: the breakpoint structure to register - * - * @bp.info->name or @bp.info->address, @bp.info->len, @bp.info->type and - * @bp->triggered must be set properly before invocation + * register_wide_hw_breakpoint - register a wide breakpoint in the kernel + * @addr: is the memory address that triggers the breakpoint + * @len: the length of the access to the memory (1 byte, 2 bytes etc...) + * @type: the type of the access to the memory (read/write/exec) + * @triggered: callback to trigger when we hit the breakpoint + * @active: should we activate it while registering it * + * @return a set of per_cpu pointers to perf events */ -int register_kernel_hw_breakpoint(struct hw_breakpoint *bp) +struct perf_event ** +register_wide_hw_breakpoint(unsigned long addr, + int len, + int type, + perf_callback_t triggered, + bool active) { - int rc; + struct perf_event **cpu_events, **pevent, *bp; + long err; + int cpu; + + cpu_events = alloc_percpu(typeof(*cpu_events)); + if (!cpu_events) + return ERR_PTR(-ENOMEM); - rc = arch_validate_hwbkpt_settings(bp, NULL); - if (rc) - return rc; + for_each_possible_cpu(cpu) { + pevent = per_cpu_ptr(cpu_events, cpu); + bp = register_kernel_hw_breakpoint_cpu(addr, len, type, + triggered, cpu, active); - spin_lock_bh(&hw_breakpoint_lock); + *pevent = bp; - rc = -ENOSPC; - /* Check if we are over-committing */ - if ((hbp_kernel_pos > 0) && (!hbp_user_refcount[hbp_kernel_pos-1])) { - hbp_kernel_pos--; - hbp_kernel[hbp_kernel_pos] = bp; - on_each_cpu(arch_update_kernel_hw_breakpoint, NULL, 1); - rc = 0; + if (IS_ERR(bp) || !bp) { + err = PTR_ERR(bp); + goto fail; + } } - spin_unlock_bh(&hw_breakpoint_lock); - return rc; + return cpu_events; + +fail: + for_each_possible_cpu(cpu) { + pevent = per_cpu_ptr(cpu_events, cpu); + if (IS_ERR(*pevent) || !*pevent) + break; + unregister_hw_breakpoint(*pevent); + } + free_percpu(cpu_events); + /* return the error if any */ + return ERR_PTR(err); } -EXPORT_SYMBOL_GPL(register_kernel_hw_breakpoint); /** - * unregister_kernel_hw_breakpoint - unregister a HW breakpoint for kernel space - * @bp: the breakpoint structure to unregister - * - * Uninstalls and unregisters @bp. + * unregister_wide_hw_breakpoint - unregister a wide breakpoint in the kernel + * @cpu_events: the per cpu set of events to unregister */ -void unregister_kernel_hw_breakpoint(struct hw_breakpoint *bp) +void unregister_wide_hw_breakpoint(struct perf_event **cpu_events) { - int i, j; - - spin_lock_bh(&hw_breakpoint_lock); - - /* Find the 'bp' in our list of breakpoints for kernel */ - for (i = hbp_kernel_pos; i < HBP_NUM; i++) - if (bp == hbp_kernel[i]) - break; + int cpu; + struct perf_event **pevent; - /* Check if we did not find a match for 'bp'. If so return early */ - if (i == HBP_NUM) { - spin_unlock_bh(&hw_breakpoint_lock); - return; + for_each_possible_cpu(cpu) { + pevent = per_cpu_ptr(cpu_events, cpu); + unregister_hw_breakpoint(*pevent); } - - /* - * We'll shift the breakpoints one-level above to compact if - * unregistration creates a hole - */ - for (j = i; j > hbp_kernel_pos; j--) - hbp_kernel[j] = hbp_kernel[j-1]; - - hbp_kernel[hbp_kernel_pos] = NULL; - on_each_cpu(arch_update_kernel_hw_breakpoint, NULL, 1); - hbp_kernel_pos++; - - spin_unlock_bh(&hw_breakpoint_lock); + free_percpu(cpu_events); } -EXPORT_SYMBOL_GPL(unregister_kernel_hw_breakpoint); + static struct notifier_block hw_breakpoint_exceptions_nb = { .notifier_call = hw_breakpoint_exceptions_notify, @@ -374,5 +283,12 @@ static int __init init_hw_breakpoint(void) { return register_die_notifier(&hw_breakpoint_exceptions_nb); } - core_initcall(init_hw_breakpoint); + + +struct pmu perf_ops_bp = { + .enable = arch_install_hw_breakpoint, + .disable = arch_uninstall_hw_breakpoint, + .read = hw_breakpoint_pmu_read, + .unthrottle = hw_breakpoint_pmu_unthrottle +}; diff --git a/kernel/perf_event.c b/kernel/perf_event.c index 5087125..98dc56b 100644 --- a/kernel/perf_event.c +++ b/kernel/perf_event.c @@ -29,6 +29,7 @@ #include <linux/kernel_stat.h> #include <linux/perf_event.h> #include <linux/ftrace_event.h> +#include <linux/hw_breakpoint.h> #include <asm/irq_regs.h> @@ -4229,6 +4230,51 @@ static void perf_event_free_filter(struct perf_event *event) #endif /* CONFIG_EVENT_PROFILE */ +#ifdef CONFIG_HAVE_HW_BREAKPOINT +static void bp_perf_event_destroy(struct perf_event *event) +{ + release_bp_slot(event); +} + +static const struct pmu *bp_perf_event_init(struct perf_event *bp) +{ + int err; + /* + * The breakpoint is already filled if we haven't created the counter + * through perf syscall + * FIXME: manage to get trigerred to NULL if it comes from syscalls + */ + if (!bp->callback) + err = register_perf_hw_breakpoint(bp); + else + err = __register_perf_hw_breakpoint(bp); + if (err) + return ERR_PTR(err); + + bp->destroy = bp_perf_event_destroy; + + return &perf_ops_bp; +} + +void perf_bp_event(struct perf_event *bp, void *regs) +{ + /* TODO */ +} +#else +static void bp_perf_event_destroy(struct perf_event *event) +{ +} + +static const struct pmu *bp_perf_event_init(struct perf_event *bp) +{ + return NULL; +} + +void perf_bp_event(struct perf_event *bp, void *regs) +{ +} +#endif + atomic_t perf_swevent_enabled[PERF_COUNT_SW_MAX]; static void sw_perf_event_destroy(struct perf_event *event) @@ -4375,6 +4421,11 @@ perf_event_alloc(struct perf_event_attr *attr, pmu = tp_perf_event_init(event); break; + case PERF_TYPE_BREAKPOINT: + pmu = bp_perf_event_init(event); + break; + + default: break; } @@ -4686,7 +4737,7 @@ perf_event_create_kernel_counter(struct perf_event_attr *attr, int cpu, ctx = find_get_context(pid, cpu); if (IS_ERR(ctx)) - return NULL ; + return NULL; event = perf_event_alloc(attr, cpu, ctx, NULL, NULL, callback, GFP_KERNEL); diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h index 91c3d0e..d72f06f 100644 --- a/kernel/trace/trace.h +++ b/kernel/trace/trace.h @@ -11,14 +11,11 @@ #include <linux/ftrace.h> #include <trace/boot.h> #include <linux/kmemtrace.h> +#include <linux/hw_breakpoint.h> #include <linux/trace_seq.h> #include <linux/ftrace_event.h> -#ifdef CONFIG_KSYM_TRACER -#include <asm/hw_breakpoint.h> -#endif - enum trace_type { __TRACE_FIRST_TYPE = 0, diff --git a/kernel/trace/trace_entries.h b/kernel/trace/trace_entries.h index e19747d..c16a08f 100644 --- a/kernel/trace/trace_entries.h +++ b/kernel/trace/trace_entries.h @@ -372,11 +372,11 @@ FTRACE_ENTRY(ksym_trace, ksym_trace_entry, F_STRUCT( __field( unsigned long, ip ) __field( unsigned char, type ) - __array( char , ksym_name, KSYM_NAME_LEN ) __array( char , cmd, TASK_COMM_LEN ) + __field( unsigned long, addr ) ), - F_printk("ip: %pF type: %d ksym_name: %s cmd: %s", + F_printk("ip: %pF type: %d ksym_name: %pS cmd: %s", (void *)__entry->ip, (unsigned int)__entry->type, - __entry->ksym_name, __entry->cmd) + (void *)__entry->addr, __entry->cmd) ); diff --git a/kernel/trace/trace_ksym.c b/kernel/trace/trace_ksym.c index 6d5609c..fea83ee 100644 --- a/kernel/trace/trace_ksym.c +++ b/kernel/trace/trace_ksym.c @@ -29,7 +29,11 @@ #include "trace_stat.h" #include "trace.h" -/* For now, let us restrict the no. of symbols traced simultaneously to number +#include <linux/hw_breakpoint.h> +#include <asm/hw_breakpoint.h> + +/* + * For now, let us restrict the no. of symbols traced simultaneously to number * of available hardware breakpoint registers. */ #define KSYM_TRACER_MAX HBP_NUM @@ -37,8 +41,10 @@ #define KSYM_TRACER_OP_LEN 3 /* rw- */ struct trace_ksym { - struct hw_breakpoint *ksym_hbp; + struct perf_event **ksym_hbp; unsigned long ksym_addr; + int type; + int len; #ifdef CONFIG_PROFILE_KSYM_TRACER unsigned long counter; #endif @@ -75,10 +81,11 @@ void ksym_collect_stats(unsigned long hbp_hit_addr) } #endif /* CONFIG_PROFILE_KSYM_TRACER */ -void ksym_hbp_handler(struct hw_breakpoint *hbp, struct pt_regs *regs) +void ksym_hbp_handler(struct perf_event *hbp, void *data) { struct ring_buffer_event *event; struct ksym_trace_entry *entry; + struct pt_regs *regs = data; struct ring_buffer *buffer; int pc; @@ -96,12 +103,12 @@ void ksym_hbp_handler(struct hw_breakpoint *hbp, struct pt_regs *regs) entry = ring_buffer_event_data(event); entry->ip = instruction_pointer(regs); - entry->type = hbp->info.type; - strlcpy(entry->ksym_name, hbp->info.name, KSYM_SYMBOL_LEN); + entry->type = hw_breakpoint_type(hbp); + entry->addr = hw_breakpoint_addr(hbp); strlcpy(entry->cmd, current->comm, TASK_COMM_LEN); #ifdef CONFIG_PROFILE_KSYM_TRACER - ksym_collect_stats(hbp->info.address); + ksym_collect_stats(hw_breakpoint_addr(hbp)); #endif /* CONFIG_PROFILE_KSYM_TRACER */ trace_buffer_unlock_commit(buffer, event, 0, pc); @@ -120,31 +127,21 @@ static int ksym_trace_get_access_type(char *str) int access = 0; if (str[0] == 'r') - access += 4; - else if (str[0] != '-') - return -EINVAL; + access |= HW_BREAKPOINT_R; if (str[1] == 'w') - access += 2; - else if (str[1] != '-') - return -EINVAL; + access |= HW_BREAKPOINT_W; - if (str[2] != '-') - return -EINVAL; + if (str[2] == 'x') + access |= HW_BREAKPOINT_X; switch (access) { - case 6: - access = HW_BREAKPOINT_RW; - break; - case 4: - access = -EINVAL; - break; - case 2: - access = HW_BREAKPOINT_WRITE; - break; + case HW_BREAKPOINT_W: + case HW_BREAKPOINT_W | HW_BREAKPOINT_R: + return access; + default: + return -EINVAL; } - - return access; } /* @@ -194,36 +191,33 @@ int process_new_ksym_entry(char *ksymname, int op, unsigned long addr) if (!entry) return -ENOMEM; - entry->ksym_hbp = kzalloc(sizeof(struct hw_breakpoint), GFP_KERNEL); - if (!entry->ksym_hbp) - goto err; - - entry->ksym_hbp->info.name = kstrdup(ksymname, GFP_KERNEL); - if (!entry->ksym_hbp->info.name) - goto err; - - entry->ksym_hbp->info.type = op; - entry->ksym_addr = entry->ksym_hbp->info.address = addr; -#ifdef CONFIG_X86 - entry->ksym_hbp->info.len = HW_BREAKPOINT_LEN_4; -#endif - entry->ksym_hbp->triggered = (void *)ksym_hbp_handler; + entry->type = op; + entry->ksym_addr = addr; + entry->len = HW_BREAKPOINT_LEN_4; + + ret = -EAGAIN; + entry->ksym_hbp = register_wide_hw_breakpoint(entry->ksym_addr, + entry->len, entry->type, + ksym_hbp_handler, true); + if (IS_ERR(entry->ksym_hbp)) { + entry->ksym_hbp = NULL; + ret = PTR_ERR(entry->ksym_hbp); + } - ret = register_kernel_hw_breakpoint(entry->ksym_hbp); - if (ret < 0) { + if (!entry->ksym_hbp) { printk(KERN_INFO "ksym_tracer request failed. Try again" " later!!\n"); - ret = -EAGAIN; goto err; } + hlist_add_head_rcu(&(entry->ksym_hlist), &ksym_filter_head); ksym_filter_entry_count++; + return 0; + err: - if (entry->ksym_hbp) - kfree(entry->ksym_hbp->info.name); - kfree(entry->ksym_hbp); kfree(entry); + return ret; } @@ -244,10 +238,10 @@ static ssize_t ksym_trace_filter_read(struct file *filp, char __user *ubuf, mutex_lock(&ksym_tracer_mutex); hlist_for_each_entry(entry, node, &ksym_filter_head, ksym_hlist) { - ret = trace_seq_printf(s, "%s:", entry->ksym_hbp->info.name); - if (entry->ksym_hbp->info.type == HW_BREAKPOINT_WRITE) + ret = trace_seq_printf(s, "%pS:", (void *)entry->ksym_addr); + if (entry->type == HW_BREAKPOINT_W) ret = trace_seq_puts(s, "-w-\n"); - else if (entry->ksym_hbp->info.type == HW_BREAKPOINT_RW) + else if (entry->type == (HW_BREAKPOINT_W | HW_BREAKPOINT_R)) ret = trace_seq_puts(s, "rw-\n"); WARN_ON_ONCE(!ret); } @@ -269,12 +263,10 @@ static void __ksym_trace_reset(void) mutex_lock(&ksym_tracer_mutex); hlist_for_each_entry_safe(entry, node, node1, &ksym_filter_head, ksym_hlist) { - unregister_kernel_hw_breakpoint(entry->ksym_hbp); + unregister_wide_hw_breakpoint(entry->ksym_hbp); ksym_filter_entry_count--; hlist_del_rcu(&(entry->ksym_hlist)); synchronize_rcu(); - kfree(entry->ksym_hbp->info.name); - kfree(entry->ksym_hbp); kfree(entry); } mutex_unlock(&ksym_tracer_mutex); @@ -327,7 +319,7 @@ static ssize_t ksym_trace_filter_write(struct file *file, hlist_for_each_entry(entry, node, &ksym_filter_head, ksym_hlist) { if (entry->ksym_addr == ksym_addr) { /* Check for malformed request: (6) */ - if (entry->ksym_hbp->info.type != op) + if (entry->type != op) changed = 1; else goto out; @@ -335,18 +327,21 @@ static ssize_t ksym_trace_filter_write(struct file *file, } } if (changed) { - unregister_kernel_hw_breakpoint(entry->ksym_hbp); - entry->ksym_hbp->info.type = op; + unregister_wide_hw_breakpoint(entry->ksym_hbp); + entry->type = op; if (op > 0) { - ret = register_kernel_hw_breakpoint(entry->ksym_hbp); - if (ret == 0) + entry->ksym_hbp = + register_wide_hw_breakpoint(entry->ksym_addr, + entry->len, entry->type, + ksym_hbp_handler, true); + if (IS_ERR(entry->ksym_hbp)) + entry->ksym_hbp = NULL; + if (!entry->ksym_hbp) goto out; } ksym_filter_entry_count--; hlist_del_rcu(&(entry->ksym_hlist)); synchronize_rcu(); - kfree(entry->ksym_hbp->info.name); - kfree(entry->ksym_hbp); kfree(entry); ret = 0; goto out; @@ -413,16 +408,16 @@ static enum print_line_t ksym_trace_output(struct trace_iterator *iter) trace_assign_type(field, entry); - ret = trace_seq_printf(s, "%11s-%-5d [%03d] %-30s ", field->cmd, - entry->pid, iter->cpu, field->ksym_name); + ret = trace_seq_printf(s, "%11s-%-5d [%03d] %pS", field->cmd, + entry->pid, iter->cpu, (char *)field->addr); if (!ret) return TRACE_TYPE_PARTIAL_LINE; switch (field->type) { - case HW_BREAKPOINT_WRITE: + case HW_BREAKPOINT_W: ret = trace_seq_printf(s, " W "); break; - case HW_BREAKPOINT_RW: + case HW_BREAKPOINT_R | HW_BREAKPOINT_W: ret = trace_seq_printf(s, " RW "); break; default: @@ -490,14 +485,13 @@ static int ksym_tracer_stat_show(struct seq_file *m, void *v) entry = hlist_entry(stat, struct trace_ksym, ksym_hlist); - if (entry->ksym_hbp) - access_type = entry->ksym_hbp->info.type; + access_type = entry->type; switch (access_type) { - case HW_BREAKPOINT_WRITE: + case HW_BREAKPOINT_W: seq_puts(m, " W "); break; - case HW_BREAKPOINT_RW: + case HW_BREAKPOINT_R | HW_BREAKPOINT_W: seq_puts(m, " RW "); break; default: diff --git a/kernel/trace/trace_selftest.c b/kernel/trace/trace_selftest.c index 7179c12..27c5072 100644 --- a/kernel/trace/trace_selftest.c +++ b/kernel/trace/trace_selftest.c @@ -828,7 +828,8 @@ trace_selftest_startup_ksym(struct tracer *trace, struct trace_array *tr) ksym_selftest_dummy = 0; /* Register the read-write tracing request */ - ret = process_new_ksym_entry(KSYM_SELFTEST_ENTRY, HW_BREAKPOINT_RW, + ret = process_new_ksym_entry(KSYM_SELFTEST_ENTRY, + HW_BREAKPOINT_R | HW_BREAKPOINT_W, (unsigned long)(&ksym_selftest_dummy)); if (ret < 0) { |