diff --git a/include/linux/trace_events.h b/include/linux/trace_events.h index 3930e676436c..1e8bbdb8da90 100644 --- a/include/linux/trace_events.h +++ b/include/linux/trace_events.h @@ -59,6 +59,17 @@ int trace_raw_output_prep(struct trace_iterator *iter, extern __printf(2, 3) void trace_event_printf(struct trace_iterator *iter, const char *fmt, ...); +/* Used to find the offset and length of dynamic fields in trace events */ +struct trace_dynamic_info { +#ifdef CONFIG_CPU_BIG_ENDIAN + u16 offset; + u16 len; +#else + u16 len; + u16 offset; +#endif +}; + /* * The trace entry - the most basic unit of tracing. This is what * is printed in the end as a single line in the trace output, such as: diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index b8870078ef58..8e64aaad5361 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -4213,8 +4213,15 @@ static void *s_start(struct seq_file *m, loff_t *pos) * will point to the same string as current_trace->name. */ mutex_lock(&trace_types_lock); - if (unlikely(tr->current_trace && iter->trace->name != tr->current_trace->name)) + if (unlikely(tr->current_trace && iter->trace->name != tr->current_trace->name)) { + /* Close iter->trace before switching to the new current tracer */ + if (iter->trace->close) + iter->trace->close(iter); *iter->trace = *tr->current_trace; + /* Reopen the new current tracer */ + if (iter->trace->open) + iter->trace->open(iter); + } mutex_unlock(&trace_types_lock); #ifdef CONFIG_TRACER_MAX_TRACE @@ -5277,11 +5284,17 @@ int tracing_set_cpumask(struct trace_array *tr, !cpumask_test_cpu(cpu, tracing_cpumask_new)) { atomic_inc(&per_cpu_ptr(tr->array_buffer.data, cpu)->disabled); ring_buffer_record_disable_cpu(tr->array_buffer.buffer, cpu); +#ifdef CONFIG_TRACER_MAX_TRACE + ring_buffer_record_disable_cpu(tr->max_buffer.buffer, cpu); +#endif } if (!cpumask_test_cpu(cpu, tr->tracing_cpumask) && cpumask_test_cpu(cpu, tracing_cpumask_new)) { atomic_dec(&per_cpu_ptr(tr->array_buffer.data, cpu)->disabled); ring_buffer_record_enable_cpu(tr->array_buffer.buffer, cpu); +#ifdef CONFIG_TRACER_MAX_TRACE + ring_buffer_record_enable_cpu(tr->max_buffer.buffer, cpu); +#endif } } arch_spin_unlock(&tr->max_lock); @@ -6705,10 +6718,36 @@ tracing_max_lat_write(struct file *filp, const char __user *ubuf, #endif +static int open_pipe_on_cpu(struct trace_array *tr, int cpu) +{ + if (cpu == RING_BUFFER_ALL_CPUS) { + if (cpumask_empty(tr->pipe_cpumask)) { + cpumask_setall(tr->pipe_cpumask); + return 0; + } + } else if (!cpumask_test_cpu(cpu, tr->pipe_cpumask)) { + cpumask_set_cpu(cpu, tr->pipe_cpumask); + return 0; + } + return -EBUSY; +} + +static void close_pipe_on_cpu(struct trace_array *tr, int cpu) +{ + if (cpu == RING_BUFFER_ALL_CPUS) { + WARN_ON(!cpumask_full(tr->pipe_cpumask)); + cpumask_clear(tr->pipe_cpumask); + } else { + WARN_ON(!cpumask_test_cpu(cpu, tr->pipe_cpumask)); + cpumask_clear_cpu(cpu, tr->pipe_cpumask); + } +} + static int tracing_open_pipe(struct inode *inode, struct file *filp) { struct trace_array *tr = inode->i_private; struct trace_iterator *iter; + int cpu; int ret; ret = tracing_check_open_get_tr(tr); @@ -6716,13 +6755,16 @@ static int tracing_open_pipe(struct inode *inode, struct file *filp) return ret; mutex_lock(&trace_types_lock); + cpu = tracing_get_cpu(inode); + ret = open_pipe_on_cpu(tr, cpu); + if (ret) + goto fail_pipe_on_cpu; /* create a buffer to store the information to pass to userspace */ iter = kzalloc(sizeof(*iter), GFP_KERNEL); if (!iter) { ret = -ENOMEM; - __trace_array_put(tr); - goto out; + goto fail_alloc_iter; } trace_seq_init(&iter->seq); @@ -6745,7 +6787,7 @@ static int tracing_open_pipe(struct inode *inode, struct file *filp) iter->tr = tr; iter->array_buffer = &tr->array_buffer; - iter->cpu_file = tracing_get_cpu(inode); + iter->cpu_file = cpu; mutex_init(&iter->mutex); filp->private_data = iter; @@ -6755,12 +6797,15 @@ static int tracing_open_pipe(struct inode *inode, struct file *filp) nonseekable_open(inode, filp); tr->trace_ref++; -out: + mutex_unlock(&trace_types_lock); return ret; fail: kfree(iter); +fail_alloc_iter: + close_pipe_on_cpu(tr, cpu); +fail_pipe_on_cpu: __trace_array_put(tr); mutex_unlock(&trace_types_lock); return ret; @@ -6777,7 +6822,7 @@ static int tracing_release_pipe(struct inode *inode, struct file *file) if (iter->trace->pipe_close) iter->trace->pipe_close(iter); - + close_pipe_on_cpu(tr, iter->cpu_file); mutex_unlock(&trace_types_lock); free_cpumask_var(iter->started); @@ -9441,6 +9486,9 @@ static struct trace_array *trace_array_create(const char *name) if (!alloc_cpumask_var(&tr->tracing_cpumask, GFP_KERNEL)) goto out_free_tr; + if (!alloc_cpumask_var(&tr->pipe_cpumask, GFP_KERNEL)) + goto out_free_tr; + tr->trace_flags = global_trace.trace_flags & ~ZEROED_TRACE_FLAGS; cpumask_copy(tr->tracing_cpumask, cpu_all_mask); @@ -9482,6 +9530,7 @@ static struct trace_array *trace_array_create(const char *name) out_free_tr: ftrace_free_ftrace_ops(tr); free_trace_buffers(tr); + free_cpumask_var(tr->pipe_cpumask); free_cpumask_var(tr->tracing_cpumask); kfree(tr->name); kfree(tr); @@ -9584,6 +9633,7 @@ static int __remove_instance(struct trace_array *tr) } kfree(tr->topts); + free_cpumask_var(tr->pipe_cpumask); free_cpumask_var(tr->tracing_cpumask); kfree(tr->name); kfree(tr); @@ -10381,12 +10431,14 @@ __init static int tracer_alloc_buffers(void) if (trace_create_savedcmd() < 0) goto out_free_temp_buffer; + if (!alloc_cpumask_var(&global_trace.pipe_cpumask, GFP_KERNEL)) + goto out_free_savedcmd; + /* TODO: make the number of buffers hot pluggable with CPUS */ if (allocate_trace_buffers(&global_trace, ring_buf_size) < 0) { MEM_FAIL(1, "tracer: failed to allocate ring buffer!\n"); - goto out_free_savedcmd; + goto out_free_pipe_cpumask; } - if (global_trace.buffer_disabled) tracing_off(); @@ -10439,6 +10491,8 @@ __init static int tracer_alloc_buffers(void) return 0; +out_free_pipe_cpumask: + free_cpumask_var(global_trace.pipe_cpumask); out_free_savedcmd: free_saved_cmdlines_buffer(savedcmd); out_free_temp_buffer: diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h index e1edc2197fc8..73eaec158473 100644 --- a/kernel/trace/trace.h +++ b/kernel/trace/trace.h @@ -377,6 +377,8 @@ struct trace_array { struct list_head events; struct trace_event_file *trace_marker_file; cpumask_var_t tracing_cpumask; /* only trace on set CPUs */ + /* one per_cpu trace_pipe can be opened by only one user */ + cpumask_var_t pipe_cpumask; int ref; int trace_ref; #ifdef CONFIG_FUNCTION_TRACER @@ -1295,6 +1297,14 @@ static inline void trace_branch_disable(void) /* set ring buffers to default size if not already done so */ int tracing_update_buffers(void); +union trace_synth_field { + u8 as_u8; + u16 as_u16; + u32 as_u32; + u64 as_u64; + struct trace_dynamic_info as_dynamic; +}; + struct ftrace_event_field { struct list_head link; const char *name; diff --git a/kernel/trace/trace_events_synth.c b/kernel/trace/trace_events_synth.c index dd398afc8e25..9897d0bfcab7 100644 --- a/kernel/trace/trace_events_synth.c +++ b/kernel/trace/trace_events_synth.c @@ -127,7 +127,7 @@ static bool synth_event_match(const char *system, const char *event, struct synth_trace_event { struct trace_entry ent; - u64 fields[]; + union trace_synth_field fields[]; }; static int synth_event_define_fields(struct trace_event_call *call) @@ -321,19 +321,19 @@ static const char *synth_field_fmt(char *type) static void print_synth_event_num_val(struct trace_seq *s, char *print_fmt, char *name, - int size, u64 val, char *space) + int size, union trace_synth_field *val, char *space) { switch (size) { case 1: - trace_seq_printf(s, print_fmt, name, (u8)val, space); + trace_seq_printf(s, print_fmt, name, val->as_u8, space); break; case 2: - trace_seq_printf(s, print_fmt, name, (u16)val, space); + trace_seq_printf(s, print_fmt, name, val->as_u16, space); break; case 4: - trace_seq_printf(s, print_fmt, name, (u32)val, space); + trace_seq_printf(s, print_fmt, name, val->as_u32, space); break; default: @@ -350,7 +350,7 @@ static enum print_line_t print_synth_event(struct trace_iterator *iter, struct trace_seq *s = &iter->seq; struct synth_trace_event *entry; struct synth_event *se; - unsigned int i, n_u64; + unsigned int i, j, n_u64; char print_fmt[32]; const char *fmt; @@ -374,43 +374,28 @@ static enum print_line_t print_synth_event(struct trace_iterator *iter, /* parameter values */ if (se->fields[i]->is_string) { if (se->fields[i]->is_dynamic) { - u32 offset, data_offset; - char *str_field; - - offset = (u32)entry->fields[n_u64]; - data_offset = offset & 0xffff; - - str_field = (char *)entry + data_offset; + union trace_synth_field *data = &entry->fields[n_u64]; trace_seq_printf(s, print_fmt, se->fields[i]->name, STR_VAR_LEN_MAX, - str_field, + (char *)entry + data->as_dynamic.offset, i == se->n_fields - 1 ? "" : " "); n_u64++; } else { trace_seq_printf(s, print_fmt, se->fields[i]->name, STR_VAR_LEN_MAX, - (char *)&entry->fields[n_u64], + (char *)&entry->fields[n_u64].as_u64, i == se->n_fields - 1 ? "" : " "); n_u64 += STR_VAR_LEN_MAX / sizeof(u64); } } else if (se->fields[i]->is_stack) { - u32 offset, data_offset, len; - unsigned long *p, *end; - - offset = (u32)entry->fields[n_u64]; - data_offset = offset & 0xffff; - len = offset >> 16; - - p = (void *)entry + data_offset; - end = (void *)p + len - (sizeof(long) - 1); + union trace_synth_field *data = &entry->fields[n_u64]; + unsigned long *p = (void *)entry + data->as_dynamic.offset; trace_seq_printf(s, "%s=STACK:\n", se->fields[i]->name); - - for (; *p && p < end; p++) - trace_seq_printf(s, "=> %pS\n", (void *)*p); + for (j = 1; j < data->as_dynamic.len / sizeof(long); j++) + trace_seq_printf(s, "=> %pS\n", (void *)p[j]); n_u64++; - } else { struct trace_print_flags __flags[] = { __def_gfpflag_names, {-1, NULL} }; @@ -419,13 +404,13 @@ static enum print_line_t print_synth_event(struct trace_iterator *iter, print_synth_event_num_val(s, print_fmt, se->fields[i]->name, se->fields[i]->size, - entry->fields[n_u64], + &entry->fields[n_u64], space); if (strcmp(se->fields[i]->type, "gfp_t") == 0) { trace_seq_puts(s, " ("); trace_print_flags_seq(s, "|", - entry->fields[n_u64], + entry->fields[n_u64].as_u64, __flags); trace_seq_putc(s, ')'); } @@ -454,21 +439,16 @@ static unsigned int trace_string(struct synth_trace_event *entry, int ret; if (is_dynamic) { - u32 data_offset; + union trace_synth_field *data = &entry->fields[*n_u64]; - data_offset = struct_size(entry, fields, event->n_u64); - data_offset += data_size; - - len = fetch_store_strlen((unsigned long)str_val); - - data_offset |= len << 16; - *(u32 *)&entry->fields[*n_u64] = data_offset; + data->as_dynamic.offset = struct_size(entry, fields, event->n_u64) + data_size; + data->as_dynamic.len = fetch_store_strlen((unsigned long)str_val); ret = fetch_store_string((unsigned long)str_val, &entry->fields[*n_u64], entry); (*n_u64)++; } else { - str_field = (char *)&entry->fields[*n_u64]; + str_field = (char *)&entry->fields[*n_u64].as_u64; #ifdef CONFIG_ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE if ((unsigned long)str_val < TASK_SIZE) @@ -492,6 +472,7 @@ static unsigned int trace_stack(struct synth_trace_event *entry, unsigned int data_size, unsigned int *n_u64) { + union trace_synth_field *data = &entry->fields[*n_u64]; unsigned int len; u32 data_offset; void *data_loc; @@ -504,10 +485,6 @@ static unsigned int trace_stack(struct synth_trace_event *entry, break; } - /* Include the zero'd element if it fits */ - if (len < HIST_STACKTRACE_DEPTH) - len++; - len *= sizeof(long); /* Find the dynamic section to copy the stack into. */ @@ -515,8 +492,9 @@ static unsigned int trace_stack(struct synth_trace_event *entry, memcpy(data_loc, stack, len); /* Fill in the field that holds the offset/len combo */ - data_offset |= len << 16; - *(u32 *)&entry->fields[*n_u64] = data_offset; + + data->as_dynamic.offset = data_offset; + data->as_dynamic.len = len; (*n_u64)++; @@ -550,7 +528,8 @@ static notrace void trace_event_raw_event_synth(void *__data, str_val = (char *)(long)var_ref_vals[val_idx]; if (event->dynamic_fields[i]->is_stack) { - len = *((unsigned long *)str_val); + /* reserve one extra element for size */ + len = *((unsigned long *)str_val) + 1; len *= sizeof(unsigned long); } else { len = fetch_store_strlen((unsigned long)str_val); @@ -592,19 +571,19 @@ static notrace void trace_event_raw_event_synth(void *__data, switch (field->size) { case 1: - *(u8 *)&entry->fields[n_u64] = (u8)val; + entry->fields[n_u64].as_u8 = (u8)val; break; case 2: - *(u16 *)&entry->fields[n_u64] = (u16)val; + entry->fields[n_u64].as_u16 = (u16)val; break; case 4: - *(u32 *)&entry->fields[n_u64] = (u32)val; + entry->fields[n_u64].as_u32 = (u32)val; break; default: - entry->fields[n_u64] = val; + entry->fields[n_u64].as_u64 = val; break; } n_u64++; @@ -1791,19 +1770,19 @@ int synth_event_trace(struct trace_event_file *file, unsigned int n_vals, ...) switch (field->size) { case 1: - *(u8 *)&state.entry->fields[n_u64] = (u8)val; + state.entry->fields[n_u64].as_u8 = (u8)val; break; case 2: - *(u16 *)&state.entry->fields[n_u64] = (u16)val; + state.entry->fields[n_u64].as_u16 = (u16)val; break; case 4: - *(u32 *)&state.entry->fields[n_u64] = (u32)val; + state.entry->fields[n_u64].as_u32 = (u32)val; break; default: - state.entry->fields[n_u64] = val; + state.entry->fields[n_u64].as_u64 = val; break; } n_u64++; @@ -1884,19 +1863,19 @@ int synth_event_trace_array(struct trace_event_file *file, u64 *vals, switch (field->size) { case 1: - *(u8 *)&state.entry->fields[n_u64] = (u8)val; + state.entry->fields[n_u64].as_u8 = (u8)val; break; case 2: - *(u16 *)&state.entry->fields[n_u64] = (u16)val; + state.entry->fields[n_u64].as_u16 = (u16)val; break; case 4: - *(u32 *)&state.entry->fields[n_u64] = (u32)val; + state.entry->fields[n_u64].as_u32 = (u32)val; break; default: - state.entry->fields[n_u64] = val; + state.entry->fields[n_u64].as_u64 = val; break; } n_u64++; @@ -2031,19 +2010,19 @@ static int __synth_event_add_val(const char *field_name, u64 val, } else { switch (field->size) { case 1: - *(u8 *)&trace_state->entry->fields[field->offset] = (u8)val; + trace_state->entry->fields[field->offset].as_u8 = (u8)val; break; case 2: - *(u16 *)&trace_state->entry->fields[field->offset] = (u16)val; + trace_state->entry->fields[field->offset].as_u16 = (u16)val; break; case 4: - *(u32 *)&trace_state->entry->fields[field->offset] = (u32)val; + trace_state->entry->fields[field->offset].as_u32 = (u32)val; break; default: - trace_state->entry->fields[field->offset] = val; + trace_state->entry->fields[field->offset].as_u64 = val; break; } } diff --git a/kernel/trace/trace_irqsoff.c b/kernel/trace/trace_irqsoff.c index 590b3d51afae..ba37f768e2f2 100644 --- a/kernel/trace/trace_irqsoff.c +++ b/kernel/trace/trace_irqsoff.c @@ -231,7 +231,8 @@ static void irqsoff_trace_open(struct trace_iterator *iter) { if (is_graph(iter->tr)) graph_trace_open(iter); - + else + iter->private = NULL; } static void irqsoff_trace_close(struct trace_iterator *iter) diff --git a/kernel/trace/trace_sched_wakeup.c b/kernel/trace/trace_sched_wakeup.c index 330aee1c1a49..0469a04a355f 100644 --- a/kernel/trace/trace_sched_wakeup.c +++ b/kernel/trace/trace_sched_wakeup.c @@ -168,6 +168,8 @@ static void wakeup_trace_open(struct trace_iterator *iter) { if (is_graph(iter->tr)) graph_trace_open(iter); + else + iter->private = NULL; } static void wakeup_trace_close(struct trace_iterator *iter) diff --git a/samples/ftrace/ftrace-direct-modify.c b/samples/ftrace/ftrace-direct-modify.c index e5ed08098ff3..e2a6a69352df 100644 --- a/samples/ftrace/ftrace-direct-modify.c +++ b/samples/ftrace/ftrace-direct-modify.c @@ -105,7 +105,7 @@ asm ( " .type my_tramp1, @function\n" " .globl my_tramp1\n" " my_tramp1:" -" bti c\n" +" hint 34\n" // bti c " sub sp, sp, #16\n" " stp x9, x30, [sp]\n" " bl my_direct_func1\n" @@ -117,7 +117,7 @@ asm ( " .type my_tramp2, @function\n" " .globl my_tramp2\n" " my_tramp2:" -" bti c\n" +" hint 34\n" // bti c " sub sp, sp, #16\n" " stp x9, x30, [sp]\n" " bl my_direct_func2\n" diff --git a/samples/ftrace/ftrace-direct-multi-modify.c b/samples/ftrace/ftrace-direct-multi-modify.c index 292cff2b3f5d..2e349834d63c 100644 --- a/samples/ftrace/ftrace-direct-multi-modify.c +++ b/samples/ftrace/ftrace-direct-multi-modify.c @@ -112,7 +112,7 @@ asm ( " .type my_tramp1, @function\n" " .globl my_tramp1\n" " my_tramp1:" -" bti c\n" +" hint 34\n" // bti c " sub sp, sp, #32\n" " stp x9, x30, [sp]\n" " str x0, [sp, #16]\n" @@ -127,7 +127,7 @@ asm ( " .type my_tramp2, @function\n" " .globl my_tramp2\n" " my_tramp2:" -" bti c\n" +" hint 34\n" // bti c " sub sp, sp, #32\n" " stp x9, x30, [sp]\n" " str x0, [sp, #16]\n" diff --git a/samples/ftrace/ftrace-direct-multi.c b/samples/ftrace/ftrace-direct-multi.c index b4391e08c913..9243dbfe4d0c 100644 --- a/samples/ftrace/ftrace-direct-multi.c +++ b/samples/ftrace/ftrace-direct-multi.c @@ -75,7 +75,7 @@ asm ( " .type my_tramp, @function\n" " .globl my_tramp\n" " my_tramp:" -" bti c\n" +" hint 34\n" // bti c " sub sp, sp, #32\n" " stp x9, x30, [sp]\n" " str x0, [sp, #16]\n" diff --git a/samples/ftrace/ftrace-direct-too.c b/samples/ftrace/ftrace-direct-too.c index e9804c5307c0..e39c3563ae4e 100644 --- a/samples/ftrace/ftrace-direct-too.c +++ b/samples/ftrace/ftrace-direct-too.c @@ -81,7 +81,7 @@ asm ( " .type my_tramp, @function\n" " .globl my_tramp\n" " my_tramp:" -" bti c\n" +" hint 34\n" // bti c " sub sp, sp, #48\n" " stp x9, x30, [sp]\n" " stp x0, x1, [sp, #16]\n" diff --git a/samples/ftrace/ftrace-direct.c b/samples/ftrace/ftrace-direct.c index 20f4a7caa810..32c477da1e9a 100644 --- a/samples/ftrace/ftrace-direct.c +++ b/samples/ftrace/ftrace-direct.c @@ -72,7 +72,7 @@ asm ( " .type my_tramp, @function\n" " .globl my_tramp\n" " my_tramp:" -" bti c\n" +" hint 34\n" // bti c " sub sp, sp, #32\n" " stp x9, x30, [sp]\n" " str x0, [sp, #16]\n" diff --git a/tools/testing/selftests/ftrace/test.d/00basic/snapshot1.tc b/tools/testing/selftests/ftrace/test.d/00basic/snapshot1.tc new file mode 100644 index 000000000000..63b76cf2a360 --- /dev/null +++ b/tools/testing/selftests/ftrace/test.d/00basic/snapshot1.tc @@ -0,0 +1,31 @@ +#!/bin/sh +# SPDX-License-Identifier: GPL-2.0 +# description: Snapshot and tracing_cpumask +# requires: trace_marker tracing_cpumask snapshot +# flags: instance + +# This testcase is constrived to reproduce a problem that the cpu buffers +# become unavailable which is due to 'record_disabled' of array_buffer and +# max_buffer being messed up. + +# Store origin cpumask +ORIG_CPUMASK=`cat tracing_cpumask` + +# Stop tracing all cpu +echo 0 > tracing_cpumask + +# Take a snapshot of the main buffer +echo 1 > snapshot + +# Restore origin cpumask, note that there should be some cpus being traced +echo ${ORIG_CPUMASK} > tracing_cpumask + +# Set tracing on +echo 1 > tracing_on + +# Write a log into buffer +echo "test input 1" > trace_marker + +# Ensure the log writed so that cpu buffers are still available +grep -q "test input 1" trace +exit 0