* [GIT pull] perf fixes for 4.15
@ 2017-12-31 16:17 Thomas Gleixner
0 siblings, 0 replies; 2+ messages in thread
From: Thomas Gleixner @ 2017-12-31 16:17 UTC (permalink / raw)
To: Linus Torvalds; +Cc: LKML, Ingo Molnar, H. Peter Anvin
Linus,
please pull the latest perf-urgent-for-linus git tree from:
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git perf-urgent-for-linus
This update contains:
- Plug a memory leak in the intel pmu init code
- clang fixes
- tooling fix to avoid including kernel headers
- A fix for jvmti to generate correct debug information for inlined code
- Replace backtick with a regular shell function
- Fix the build in hardened environments
Thanks,
tglx
------------------>
Arnaldo Carvalho de Melo (2):
tools arch s390: Do not include header files from the kernel sources
x86/asm: Allow again using asm.h when building for the 'bpf' clang target
Ben Gainey (1):
perf jvmti: Generate correct debug information for inlined code
Jiri Olsa (2):
perf tools: Use shell function for perl cflags retrieval
perf tools: Fix up build in hardened environments
Thomas Gleixner (1):
perf/x86/intel: Plug memory leak in intel_pmu_init()
arch/x86/events/intel/core.c | 5 +-
arch/x86/include/asm/asm.h | 2 +
tools/arch/s390/include/uapi/asm/perf_regs.h | 44 ++++++++
tools/perf/Makefile.config | 9 +-
tools/perf/arch/s390/include/perf_regs.h | 2 +-
| 1 +
tools/perf/jvmti/jvmti_agent.c | 16 +--
tools/perf/jvmti/jvmti_agent.h | 7 +-
tools/perf/jvmti/libjvmti.c | 147 ++++++++++++++++++++++-----
9 files changed, 190 insertions(+), 43 deletions(-)
create mode 100644 tools/arch/s390/include/uapi/asm/perf_regs.h
diff --git a/arch/x86/events/intel/core.c b/arch/x86/events/intel/core.c
index 09c26a4f139c..731153a4681e 100644
--- a/arch/x86/events/intel/core.c
+++ b/arch/x86/events/intel/core.c
@@ -3847,6 +3847,8 @@ static struct attribute *intel_pmu_attrs[] = {
__init int intel_pmu_init(void)
{
+ struct attribute **extra_attr = NULL;
+ struct attribute **to_free = NULL;
union cpuid10_edx edx;
union cpuid10_eax eax;
union cpuid10_ebx ebx;
@@ -3854,7 +3856,6 @@ __init int intel_pmu_init(void)
unsigned int unused;
struct extra_reg *er;
int version, i;
- struct attribute **extra_attr = NULL;
char *name;
if (!cpu_has(&boot_cpu_data, X86_FEATURE_ARCH_PERFMON)) {
@@ -4294,6 +4295,7 @@ __init int intel_pmu_init(void)
extra_attr = boot_cpu_has(X86_FEATURE_RTM) ?
hsw_format_attr : nhm_format_attr;
extra_attr = merge_attr(extra_attr, skl_format_attr);
+ to_free = extra_attr;
x86_pmu.cpu_events = get_hsw_events_attrs();
intel_pmu_pebs_data_source_skl(
boot_cpu_data.x86_model == INTEL_FAM6_SKYLAKE_X);
@@ -4401,6 +4403,7 @@ __init int intel_pmu_init(void)
pr_cont("full-width counters, ");
}
+ kfree(to_free);
return 0;
}
diff --git a/arch/x86/include/asm/asm.h b/arch/x86/include/asm/asm.h
index 219faaec51df..386a6900e206 100644
--- a/arch/x86/include/asm/asm.h
+++ b/arch/x86/include/asm/asm.h
@@ -136,6 +136,7 @@
#endif
#ifndef __ASSEMBLY__
+#ifndef __BPF__
/*
* This output constraint should be used for any inline asm which has a "call"
* instruction. Otherwise the asm may be inserted before the frame pointer
@@ -145,5 +146,6 @@
register unsigned long current_stack_pointer asm(_ASM_SP);
#define ASM_CALL_CONSTRAINT "+r" (current_stack_pointer)
#endif
+#endif
#endif /* _ASM_X86_ASM_H */
diff --git a/tools/arch/s390/include/uapi/asm/perf_regs.h b/tools/arch/s390/include/uapi/asm/perf_regs.h
new file mode 100644
index 000000000000..d17dd9e5d516
--- /dev/null
+++ b/tools/arch/s390/include/uapi/asm/perf_regs.h
@@ -0,0 +1,44 @@
+/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
+#ifndef _ASM_S390_PERF_REGS_H
+#define _ASM_S390_PERF_REGS_H
+
+enum perf_event_s390_regs {
+ PERF_REG_S390_R0,
+ PERF_REG_S390_R1,
+ PERF_REG_S390_R2,
+ PERF_REG_S390_R3,
+ PERF_REG_S390_R4,
+ PERF_REG_S390_R5,
+ PERF_REG_S390_R6,
+ PERF_REG_S390_R7,
+ PERF_REG_S390_R8,
+ PERF_REG_S390_R9,
+ PERF_REG_S390_R10,
+ PERF_REG_S390_R11,
+ PERF_REG_S390_R12,
+ PERF_REG_S390_R13,
+ PERF_REG_S390_R14,
+ PERF_REG_S390_R15,
+ PERF_REG_S390_FP0,
+ PERF_REG_S390_FP1,
+ PERF_REG_S390_FP2,
+ PERF_REG_S390_FP3,
+ PERF_REG_S390_FP4,
+ PERF_REG_S390_FP5,
+ PERF_REG_S390_FP6,
+ PERF_REG_S390_FP7,
+ PERF_REG_S390_FP8,
+ PERF_REG_S390_FP9,
+ PERF_REG_S390_FP10,
+ PERF_REG_S390_FP11,
+ PERF_REG_S390_FP12,
+ PERF_REG_S390_FP13,
+ PERF_REG_S390_FP14,
+ PERF_REG_S390_FP15,
+ PERF_REG_S390_MASK,
+ PERF_REG_S390_PC,
+
+ PERF_REG_S390_MAX
+};
+
+#endif /* _ASM_S390_PERF_REGS_H */
diff --git a/tools/perf/Makefile.config b/tools/perf/Makefile.config
index ed65e82f034e..0294bfb6c5f8 100644
--- a/tools/perf/Makefile.config
+++ b/tools/perf/Makefile.config
@@ -188,9 +188,7 @@ ifdef PYTHON_CONFIG
PYTHON_EMBED_LDFLAGS := $(call strip-libs,$(PYTHON_EMBED_LDOPTS))
PYTHON_EMBED_LIBADD := $(call grep-libs,$(PYTHON_EMBED_LDOPTS)) -lutil
PYTHON_EMBED_CCOPTS := $(shell $(PYTHON_CONFIG_SQ) --cflags 2>/dev/null)
- ifeq ($(CC_NO_CLANG), 1)
- PYTHON_EMBED_CCOPTS := $(filter-out -specs=%,$(PYTHON_EMBED_CCOPTS))
- endif
+ PYTHON_EMBED_CCOPTS := $(filter-out -specs=%,$(PYTHON_EMBED_CCOPTS))
FLAGS_PYTHON_EMBED := $(PYTHON_EMBED_CCOPTS) $(PYTHON_EMBED_LDOPTS)
endif
@@ -576,14 +574,15 @@ ifndef NO_GTK2
endif
endif
-
ifdef NO_LIBPERL
CFLAGS += -DNO_LIBPERL
else
PERL_EMBED_LDOPTS = $(shell perl -MExtUtils::Embed -e ldopts 2>/dev/null)
PERL_EMBED_LDFLAGS = $(call strip-libs,$(PERL_EMBED_LDOPTS))
PERL_EMBED_LIBADD = $(call grep-libs,$(PERL_EMBED_LDOPTS))
- PERL_EMBED_CCOPTS = `perl -MExtUtils::Embed -e ccopts 2>/dev/null`
+ PERL_EMBED_CCOPTS = $(shell perl -MExtUtils::Embed -e ccopts 2>/dev/null)
+ PERL_EMBED_CCOPTS := $(filter-out -specs=%,$(PERL_EMBED_CCOPTS))
+ PERL_EMBED_LDOPTS := $(filter-out -specs=%,$(PERL_EMBED_LDOPTS))
FLAGS_PERL_EMBED=$(PERL_EMBED_CCOPTS) $(PERL_EMBED_LDOPTS)
ifneq ($(feature-libperl), 1)
diff --git a/tools/perf/arch/s390/include/perf_regs.h b/tools/perf/arch/s390/include/perf_regs.h
index d2df54a6bc5a..bcfbaed78cc2 100644
--- a/tools/perf/arch/s390/include/perf_regs.h
+++ b/tools/perf/arch/s390/include/perf_regs.h
@@ -3,7 +3,7 @@
#include <stdlib.h>
#include <linux/types.h>
-#include <../../../../arch/s390/include/uapi/asm/perf_regs.h>
+#include <asm/perf_regs.h>
void perf_regs_load(u64 *regs);
--git a/tools/perf/check-headers.sh b/tools/perf/check-headers.sh
index 6db9d809fe97..3e64f10b6d66 100755
--- a/tools/perf/check-headers.sh
+++ b/tools/perf/check-headers.sh
@@ -21,6 +21,7 @@ arch/x86/include/asm/cpufeatures.h
arch/arm/include/uapi/asm/perf_regs.h
arch/arm64/include/uapi/asm/perf_regs.h
arch/powerpc/include/uapi/asm/perf_regs.h
+arch/s390/include/uapi/asm/perf_regs.h
arch/x86/include/uapi/asm/perf_regs.h
arch/x86/include/uapi/asm/kvm.h
arch/x86/include/uapi/asm/kvm_perf.h
diff --git a/tools/perf/jvmti/jvmti_agent.c b/tools/perf/jvmti/jvmti_agent.c
index cf36de7ea255..0c6d1002b524 100644
--- a/tools/perf/jvmti/jvmti_agent.c
+++ b/tools/perf/jvmti/jvmti_agent.c
@@ -384,13 +384,13 @@ jvmti_write_code(void *agent, char const *sym,
}
int
-jvmti_write_debug_info(void *agent, uint64_t code, const char *file,
- jvmti_line_info_t *li, int nr_lines)
+jvmti_write_debug_info(void *agent, uint64_t code,
+ int nr_lines, jvmti_line_info_t *li,
+ const char * const * file_names)
{
struct jr_code_debug_info rec;
- size_t sret, len, size, flen;
+ size_t sret, len, size, flen = 0;
uint64_t addr;
- const char *fn = file;
FILE *fp = agent;
int i;
@@ -405,7 +405,9 @@ jvmti_write_debug_info(void *agent, uint64_t code, const char *file,
return -1;
}
- flen = strlen(file) + 1;
+ for (i = 0; i < nr_lines; ++i) {
+ flen += strlen(file_names[i]) + 1;
+ }
rec.p.id = JIT_CODE_DEBUG_INFO;
size = sizeof(rec);
@@ -421,7 +423,7 @@ jvmti_write_debug_info(void *agent, uint64_t code, const char *file,
* file[] : source file name
*/
size += nr_lines * sizeof(struct debug_entry);
- size += flen * nr_lines;
+ size += flen;
rec.p.total_size = size;
/*
@@ -452,7 +454,7 @@ jvmti_write_debug_info(void *agent, uint64_t code, const char *file,
if (sret != 1)
goto error;
- sret = fwrite_unlocked(fn, flen, 1, fp);
+ sret = fwrite_unlocked(file_names[i], strlen(file_names[i]) + 1, 1, fp);
if (sret != 1)
goto error;
}
diff --git a/tools/perf/jvmti/jvmti_agent.h b/tools/perf/jvmti/jvmti_agent.h
index fe32d8344a82..6ed82f6c06dd 100644
--- a/tools/perf/jvmti/jvmti_agent.h
+++ b/tools/perf/jvmti/jvmti_agent.h
@@ -14,6 +14,7 @@ typedef struct {
unsigned long pc;
int line_number;
int discrim; /* discriminator -- 0 for now */
+ jmethodID methodID;
} jvmti_line_info_t;
void *jvmti_open(void);
@@ -22,11 +23,9 @@ int jvmti_write_code(void *agent, char const *symbol_name,
uint64_t vma, void const *code,
const unsigned int code_size);
-int jvmti_write_debug_info(void *agent,
- uint64_t code,
- const char *file,
+int jvmti_write_debug_info(void *agent, uint64_t code, int nr_lines,
jvmti_line_info_t *li,
- int nr_lines);
+ const char * const * file_names);
#if defined(__cplusplus)
}
diff --git a/tools/perf/jvmti/libjvmti.c b/tools/perf/jvmti/libjvmti.c
index c62c9fc9a525..6add3e982614 100644
--- a/tools/perf/jvmti/libjvmti.c
+++ b/tools/perf/jvmti/libjvmti.c
@@ -47,6 +47,7 @@ do_get_line_numbers(jvmtiEnv *jvmti, void *pc, jmethodID m, jint bci,
tab[lines].pc = (unsigned long)pc;
tab[lines].line_number = loc_tab[i].line_number;
tab[lines].discrim = 0; /* not yet used */
+ tab[lines].methodID = m;
lines++;
} else {
break;
@@ -125,6 +126,99 @@ get_line_numbers(jvmtiEnv *jvmti, const void *compile_info, jvmti_line_info_t **
return JVMTI_ERROR_NONE;
}
+static void
+copy_class_filename(const char * class_sign, const char * file_name, char * result, size_t max_length)
+{
+ /*
+ * Assume path name is class hierarchy, this is a common practice with Java programs
+ */
+ if (*class_sign == 'L') {
+ int j, i = 0;
+ char *p = strrchr(class_sign, '/');
+ if (p) {
+ /* drop the 'L' prefix and copy up to the final '/' */
+ for (i = 0; i < (p - class_sign); i++)
+ result[i] = class_sign[i+1];
+ }
+ /*
+ * append file name, we use loops and not string ops to avoid modifying
+ * class_sign which is used later for the symbol name
+ */
+ for (j = 0; i < (max_length - 1) && file_name && j < strlen(file_name); j++, i++)
+ result[i] = file_name[j];
+
+ result[i] = '\0';
+ } else {
+ /* fallback case */
+ size_t file_name_len = strlen(file_name);
+ strncpy(result, file_name, file_name_len < max_length ? file_name_len : max_length);
+ }
+}
+
+static jvmtiError
+get_source_filename(jvmtiEnv *jvmti, jmethodID methodID, char ** buffer)
+{
+ jvmtiError ret;
+ jclass decl_class;
+ char *file_name = NULL;
+ char *class_sign = NULL;
+ char fn[PATH_MAX];
+ size_t len;
+
+ ret = (*jvmti)->GetMethodDeclaringClass(jvmti, methodID, &decl_class);
+ if (ret != JVMTI_ERROR_NONE) {
+ print_error(jvmti, "GetMethodDeclaringClass", ret);
+ return ret;
+ }
+
+ ret = (*jvmti)->GetSourceFileName(jvmti, decl_class, &file_name);
+ if (ret != JVMTI_ERROR_NONE) {
+ print_error(jvmti, "GetSourceFileName", ret);
+ return ret;
+ }
+
+ ret = (*jvmti)->GetClassSignature(jvmti, decl_class, &class_sign, NULL);
+ if (ret != JVMTI_ERROR_NONE) {
+ print_error(jvmti, "GetClassSignature", ret);
+ goto free_file_name_error;
+ }
+
+ copy_class_filename(class_sign, file_name, fn, PATH_MAX);
+ len = strlen(fn);
+ *buffer = malloc((len + 1) * sizeof(char));
+ if (!*buffer) {
+ print_error(jvmti, "GetClassSignature", ret);
+ ret = JVMTI_ERROR_OUT_OF_MEMORY;
+ goto free_class_sign_error;
+ }
+ strcpy(*buffer, fn);
+ ret = JVMTI_ERROR_NONE;
+
+free_class_sign_error:
+ (*jvmti)->Deallocate(jvmti, (unsigned char *)class_sign);
+free_file_name_error:
+ (*jvmti)->Deallocate(jvmti, (unsigned char *)file_name);
+
+ return ret;
+}
+
+static jvmtiError
+fill_source_filenames(jvmtiEnv *jvmti, int nr_lines,
+ const jvmti_line_info_t * line_tab,
+ char ** file_names)
+{
+ int index;
+ jvmtiError ret;
+
+ for (index = 0; index < nr_lines; ++index) {
+ ret = get_source_filename(jvmti, line_tab[index].methodID, &(file_names[index]));
+ if (ret != JVMTI_ERROR_NONE)
+ return ret;
+ }
+
+ return JVMTI_ERROR_NONE;
+}
+
static void JNICALL
compiled_method_load_cb(jvmtiEnv *jvmti,
jmethodID method,
@@ -135,16 +229,18 @@ compiled_method_load_cb(jvmtiEnv *jvmti,
const void *compile_info)
{
jvmti_line_info_t *line_tab = NULL;
+ char ** line_file_names = NULL;
jclass decl_class;
char *class_sign = NULL;
char *func_name = NULL;
char *func_sign = NULL;
- char *file_name= NULL;
+ char *file_name = NULL;
char fn[PATH_MAX];
uint64_t addr = (uint64_t)(uintptr_t)code_addr;
jvmtiError ret;
int nr_lines = 0; /* in line_tab[] */
size_t len;
+ int output_debug_info = 0;
ret = (*jvmti)->GetMethodDeclaringClass(jvmti, method,
&decl_class);
@@ -158,6 +254,19 @@ compiled_method_load_cb(jvmtiEnv *jvmti,
if (ret != JVMTI_ERROR_NONE) {
warnx("jvmti: cannot get line table for method");
nr_lines = 0;
+ } else if (nr_lines > 0) {
+ line_file_names = malloc(sizeof(char*) * nr_lines);
+ if (!line_file_names) {
+ warnx("jvmti: cannot allocate space for line table method names");
+ } else {
+ memset(line_file_names, 0, sizeof(char*) * nr_lines);
+ ret = fill_source_filenames(jvmti, nr_lines, line_tab, line_file_names);
+ if (ret != JVMTI_ERROR_NONE) {
+ warnx("jvmti: fill_source_filenames failed");
+ } else {
+ output_debug_info = 1;
+ }
+ }
}
}
@@ -181,33 +290,14 @@ compiled_method_load_cb(jvmtiEnv *jvmti,
goto error;
}
- /*
- * Assume path name is class hierarchy, this is a common practice with Java programs
- */
- if (*class_sign == 'L') {
- int j, i = 0;
- char *p = strrchr(class_sign, '/');
- if (p) {
- /* drop the 'L' prefix and copy up to the final '/' */
- for (i = 0; i < (p - class_sign); i++)
- fn[i] = class_sign[i+1];
- }
- /*
- * append file name, we use loops and not string ops to avoid modifying
- * class_sign which is used later for the symbol name
- */
- for (j = 0; i < (PATH_MAX - 1) && file_name && j < strlen(file_name); j++, i++)
- fn[i] = file_name[j];
- fn[i] = '\0';
- } else {
- /* fallback case */
- strcpy(fn, file_name);
- }
+ copy_class_filename(class_sign, file_name, fn, PATH_MAX);
+
/*
* write source line info record if we have it
*/
- if (jvmti_write_debug_info(jvmti_agent, addr, fn, line_tab, nr_lines))
- warnx("jvmti: write_debug_info() failed");
+ if (output_debug_info)
+ if (jvmti_write_debug_info(jvmti_agent, addr, nr_lines, line_tab, (const char * const *) line_file_names))
+ warnx("jvmti: write_debug_info() failed");
len = strlen(func_name) + strlen(class_sign) + strlen(func_sign) + 2;
{
@@ -223,6 +313,13 @@ compiled_method_load_cb(jvmtiEnv *jvmti,
(*jvmti)->Deallocate(jvmti, (unsigned char *)class_sign);
(*jvmti)->Deallocate(jvmti, (unsigned char *)file_name);
free(line_tab);
+ while (line_file_names && (nr_lines > 0)) {
+ if (line_file_names[nr_lines - 1]) {
+ free(line_file_names[nr_lines - 1]);
+ }
+ nr_lines -= 1;
+ }
+ free(line_file_names);
}
static void JNICALL
^ permalink raw reply related [flat|nested] 2+ messages in thread
* [GIT pull] perf fixes for 4.15
@ 2018-01-28 10:19 Thomas Gleixner
0 siblings, 0 replies; 2+ messages in thread
From: Thomas Gleixner @ 2018-01-28 10:19 UTC (permalink / raw)
To: Linus Torvalds; +Cc: LKML, Ingo Molnar, Peter Zijlstra
Linus,
please pull the latest perf-urgent-for-linus git tree from:
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git perf-urgent-for-linus
Four patches which all address lock inversions and deadlocks in the perf
core code and the Intel debug store.
Thanks,
tglx
------------------>
Peter Zijlstra (4):
perf/core: Fix lock inversion between perf,trace,cpuhp
perf/core: Fix another perf,trace,cpuhp lock inversion
perf/core: Fix ctx::mutex deadlock
perf/x86: Fix perf,x86,cpuhp deadlock
arch/x86/events/intel/ds.c | 33 +++++++++++++++++---------------
kernel/events/core.c | 47 +++++++++++++++++++++++++++++++++++++++++-----
2 files changed, 60 insertions(+), 20 deletions(-)
diff --git a/arch/x86/events/intel/ds.c b/arch/x86/events/intel/ds.c
index 8156e47da7ba..18c25ab28557 100644
--- a/arch/x86/events/intel/ds.c
+++ b/arch/x86/events/intel/ds.c
@@ -372,10 +372,9 @@ static int alloc_pebs_buffer(int cpu)
static void release_pebs_buffer(int cpu)
{
struct cpu_hw_events *hwev = per_cpu_ptr(&cpu_hw_events, cpu);
- struct debug_store *ds = hwev->ds;
void *cea;
- if (!ds || !x86_pmu.pebs)
+ if (!x86_pmu.pebs)
return;
kfree(per_cpu(insn_buffer, cpu));
@@ -384,7 +383,6 @@ static void release_pebs_buffer(int cpu)
/* Clear the fixmap */
cea = &get_cpu_entry_area(cpu)->cpu_debug_buffers.pebs_buffer;
ds_clear_cea(cea, x86_pmu.pebs_buffer_size);
- ds->pebs_buffer_base = 0;
dsfree_pages(hwev->ds_pebs_vaddr, x86_pmu.pebs_buffer_size);
hwev->ds_pebs_vaddr = NULL;
}
@@ -419,16 +417,14 @@ static int alloc_bts_buffer(int cpu)
static void release_bts_buffer(int cpu)
{
struct cpu_hw_events *hwev = per_cpu_ptr(&cpu_hw_events, cpu);
- struct debug_store *ds = hwev->ds;
void *cea;
- if (!ds || !x86_pmu.bts)
+ if (!x86_pmu.bts)
return;
/* Clear the fixmap */
cea = &get_cpu_entry_area(cpu)->cpu_debug_buffers.bts_buffer;
ds_clear_cea(cea, BTS_BUFFER_SIZE);
- ds->bts_buffer_base = 0;
dsfree_pages(hwev->ds_bts_vaddr, BTS_BUFFER_SIZE);
hwev->ds_bts_vaddr = NULL;
}
@@ -454,16 +450,22 @@ void release_ds_buffers(void)
if (!x86_pmu.bts && !x86_pmu.pebs)
return;
- get_online_cpus();
- for_each_online_cpu(cpu)
+ for_each_possible_cpu(cpu)
+ release_ds_buffer(cpu);
+
+ for_each_possible_cpu(cpu) {
+ /*
+ * Again, ignore errors from offline CPUs, they will no longer
+ * observe cpu_hw_events.ds and not program the DS_AREA when
+ * they come up.
+ */
fini_debug_store_on_cpu(cpu);
+ }
for_each_possible_cpu(cpu) {
release_pebs_buffer(cpu);
release_bts_buffer(cpu);
- release_ds_buffer(cpu);
}
- put_online_cpus();
}
void reserve_ds_buffers(void)
@@ -483,8 +485,6 @@ void reserve_ds_buffers(void)
if (!x86_pmu.pebs)
pebs_err = 1;
- get_online_cpus();
-
for_each_possible_cpu(cpu) {
if (alloc_ds_buffer(cpu)) {
bts_err = 1;
@@ -521,11 +521,14 @@ void reserve_ds_buffers(void)
if (x86_pmu.pebs && !pebs_err)
x86_pmu.pebs_active = 1;
- for_each_online_cpu(cpu)
+ for_each_possible_cpu(cpu) {
+ /*
+ * Ignores wrmsr_on_cpu() errors for offline CPUs they
+ * will get this call through intel_pmu_cpu_starting().
+ */
init_debug_store_on_cpu(cpu);
+ }
}
-
- put_online_cpus();
}
/*
diff --git a/kernel/events/core.c b/kernel/events/core.c
index 4df5b695bf0d..5d8f4031f8d5 100644
--- a/kernel/events/core.c
+++ b/kernel/events/core.c
@@ -1231,6 +1231,10 @@ static void put_ctx(struct perf_event_context *ctx)
* perf_event_context::lock
* perf_event::mmap_mutex
* mmap_sem
+ *
+ * cpu_hotplug_lock
+ * pmus_lock
+ * cpuctx->mutex / perf_event_context::mutex
*/
static struct perf_event_context *
perf_event_ctx_lock_nested(struct perf_event *event, int nesting)
@@ -4196,6 +4200,7 @@ int perf_event_release_kernel(struct perf_event *event)
{
struct perf_event_context *ctx = event->ctx;
struct perf_event *child, *tmp;
+ LIST_HEAD(free_list);
/*
* If we got here through err_file: fput(event_file); we will not have
@@ -4268,8 +4273,7 @@ int perf_event_release_kernel(struct perf_event *event)
struct perf_event, child_list);
if (tmp == child) {
perf_remove_from_context(child, DETACH_GROUP);
- list_del(&child->child_list);
- free_event(child);
+ list_move(&child->child_list, &free_list);
/*
* This matches the refcount bump in inherit_event();
* this can't be the last reference.
@@ -4284,6 +4288,11 @@ int perf_event_release_kernel(struct perf_event *event)
}
mutex_unlock(&event->child_mutex);
+ list_for_each_entry_safe(child, tmp, &free_list, child_list) {
+ list_del(&child->child_list);
+ free_event(child);
+ }
+
no_ctx:
put_event(event); /* Must be the 'last' reference */
return 0;
@@ -8516,6 +8525,29 @@ perf_event_set_addr_filter(struct perf_event *event, char *filter_str)
return ret;
}
+static int
+perf_tracepoint_set_filter(struct perf_event *event, char *filter_str)
+{
+ struct perf_event_context *ctx = event->ctx;
+ int ret;
+
+ /*
+ * Beware, here be dragons!!
+ *
+ * the tracepoint muck will deadlock against ctx->mutex, but the tracepoint
+ * stuff does not actually need it. So temporarily drop ctx->mutex. As per
+ * perf_event_ctx_lock() we already have a reference on ctx.
+ *
+ * This can result in event getting moved to a different ctx, but that
+ * does not affect the tracepoint state.
+ */
+ mutex_unlock(&ctx->mutex);
+ ret = ftrace_profile_set_filter(event, event->attr.config, filter_str);
+ mutex_lock(&ctx->mutex);
+
+ return ret;
+}
+
static int perf_event_set_filter(struct perf_event *event, void __user *arg)
{
char *filter_str;
@@ -8532,8 +8564,7 @@ static int perf_event_set_filter(struct perf_event *event, void __user *arg)
if (IS_ENABLED(CONFIG_EVENT_TRACING) &&
event->attr.type == PERF_TYPE_TRACEPOINT)
- ret = ftrace_profile_set_filter(event, event->attr.config,
- filter_str);
+ ret = perf_tracepoint_set_filter(event, filter_str);
else if (has_addr_filter(event))
ret = perf_event_set_addr_filter(event, filter_str);
@@ -9168,7 +9199,13 @@ static int perf_try_init_event(struct pmu *pmu, struct perf_event *event)
if (!try_module_get(pmu->module))
return -ENODEV;
- if (event->group_leader != event) {
+ /*
+ * A number of pmu->event_init() methods iterate the sibling_list to,
+ * for example, validate if the group fits on the PMU. Therefore,
+ * if this is a sibling event, acquire the ctx->mutex to protect
+ * the sibling_list.
+ */
+ if (event->group_leader != event && pmu->task_ctx_nr != perf_sw_context) {
/*
* This ctx->mutex can nest when we're called through
* inheritance. See the perf_event_ctx_lock_nested() comment.
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2017-12-31 16:17 [GIT pull] perf fixes for 4.15 Thomas Gleixner
2018-01-28 10:19 Thomas Gleixner
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