Merge branch 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull perf updates from Ingo Molnar:
 "Kernel side changes:

   - Ftrace is one of the last W^X violators (after this only KLP is
     left). These patches move it over to the generic text_poke()
     interface and thereby get rid of this oddity. This requires a
     surprising amount of surgery, by Peter Zijlstra.

   - x86/AMD PMUs: add support for 'Large Increment per Cycle Events' to
     count certain types of events that have a special, quirky hw ABI
     (by Kim Phillips)

   - kprobes fixes by Masami Hiramatsu

  Lots of tooling updates as well, the following subcommands were
  updated: annotate/report/top, c2c, clang, record, report/top TUI,
  sched timehist, tests; plus updates were done to the gtk ui, libperf,
  headers and the parser"

* 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (57 commits)
  perf/x86/amd: Add support for Large Increment per Cycle Events
  perf/x86/amd: Constrain Large Increment per Cycle events
  perf/x86/intel/rapl: Add Comet Lake support
  tracing: Initialize ret in syscall_enter_define_fields()
  perf header: Use last modification time for timestamp
  perf c2c: Fix return type for histogram sorting comparision functions
  perf beauty sockaddr: Fix augmented syscall format warning
  perf/ui/gtk: Fix gtk2 build
  perf ui gtk: Add missing zalloc object
  perf tools: Use %define api.pure full instead of %pure-parser
  libperf: Setup initial evlist::all_cpus value
  perf report: Fix no libunwind compiled warning break s390 issue
  perf tools: Support --prefix/--prefix-strip
  perf report: Clarify in help that --children is default
  tools build: Fix test-clang.cpp with Clang 8+
  perf clang: Fix build with Clang 9
  kprobes: Fix optimize_kprobe()/unoptimize_kprobe() cancellation logic
  tools lib: Fix builds when glibc contains strlcpy()
  perf report/top: Make 'e' visible in the help and make it toggle showing callchains
  perf report/top: Do not offer annotation for symbols without samples
  ...

Author: torvalds

arch/arm/kernel/Makefile

@@ -53,8 +53,8 @@ obj-$(CONFIG_HAVE_ARM_SCU)	+= smp_scu.o
 obj-$(CONFIG_HAVE_ARM_TWD)	+= smp_twd.o
 obj-$(CONFIG_ARM_ARCH_TIMER)	+= arch_timer.o
 obj-$(CONFIG_FUNCTION_TRACER)	+= entry-ftrace.o
-obj-$(CONFIG_DYNAMIC_FTRACE)	+= ftrace.o insn.o
-obj-$(CONFIG_FUNCTION_GRAPH_TRACER)	+= ftrace.o insn.o
+obj-$(CONFIG_DYNAMIC_FTRACE)	+= ftrace.o insn.o patch.o
+obj-$(CONFIG_FUNCTION_GRAPH_TRACER)	+= ftrace.o insn.o patch.o
 obj-$(CONFIG_JUMP_LABEL)	+= jump_label.o insn.o patch.o
 obj-$(CONFIG_KEXEC)		+= machine_kexec.o relocate_kernel.o
 # Main staffs in KPROBES are in arch/arm/probes/ .

arch/arm/kernel/ftrace.c

@@ -22,6 +22,7 @@
 #include <asm/ftrace.h>
 #include <asm/insn.h>
 #include <asm/set_memory.h>
+#include <asm/patch.h>
 
 #ifdef CONFIG_THUMB2_KERNEL
 #define	NOP		0xf85deb04	/* pop.w {lr} */
@@ -35,9 +36,7 @@ static int __ftrace_modify_code(void *data)
 {
 	int *command = data;
 
-	set_kernel_text_rw();
 	ftrace_modify_all_code(*command);
-	set_kernel_text_ro();
 
 	return 0;
 }
@@ -59,13 +58,11 @@ static unsigned long adjust_address(struct dyn_ftrace *rec, unsigned long addr)
 
 int ftrace_arch_code_modify_prepare(void)
 {
-	set_all_modules_text_rw();
 	return 0;
 }
 
 int ftrace_arch_code_modify_post_process(void)
 {
-	set_all_modules_text_ro();
 	/* Make sure any TLB misses during machine stop are cleared. */
 	flush_tlb_all();
 	return 0;
@@ -97,10 +94,7 @@ static int ftrace_modify_code(unsigned long pc, unsigned long old,
 			return -EINVAL;
 	}
 
-	if (probe_kernel_write((void *)pc, &new, MCOUNT_INSN_SIZE))
-		return -EPERM;
-
-	flush_icache_range(pc, pc + MCOUNT_INSN_SIZE);
+	__patch_text((void *)pc, new);
 
 	return 0;
 }

arch/nds32/kernel/ftrace.c

@@ -89,18 +89,6 @@ int __init ftrace_dyn_arch_init(void)
 	return 0;
 }
 
-int ftrace_arch_code_modify_prepare(void)
-{
-	set_all_modules_text_rw();
-	return 0;
-}
-
-int ftrace_arch_code_modify_post_process(void)
-{
-	set_all_modules_text_ro();
-	return 0;
-}
-
 static unsigned long gen_sethi_insn(unsigned long addr)
 {
 	unsigned long opcode = 0x46000000;

arch/x86/events/amd/core.c

@@ -14,6 +14,10 @@
 static DEFINE_PER_CPU(unsigned long, perf_nmi_tstamp);
 static unsigned long perf_nmi_window;
 
+/* AMD Event 0xFFF: Merge.  Used with Large Increment per Cycle events */
+#define AMD_MERGE_EVENT ((0xFULL << 32) | 0xFFULL)
+#define AMD_MERGE_EVENT_ENABLE (AMD_MERGE_EVENT | ARCH_PERFMON_EVENTSEL_ENABLE)
+
 static __initconst const u64 amd_hw_cache_event_ids
 				[PERF_COUNT_HW_CACHE_MAX]
 				[PERF_COUNT_HW_CACHE_OP_MAX]
@@ -301,6 +305,25 @@ static inline int amd_pmu_addr_offset(int index, bool eventsel)
 	return offset;
 }
 
+/*
+ * AMD64 events are detected based on their event codes.
+ */
+static inline unsigned int amd_get_event_code(struct hw_perf_event *hwc)
+{
+	return ((hwc->config >> 24) & 0x0f00) | (hwc->config & 0x00ff);
+}
+
+static inline bool amd_is_pair_event_code(struct hw_perf_event *hwc)
+{
+	if (!(x86_pmu.flags & PMU_FL_PAIR))
+		return false;
+
+	switch (amd_get_event_code(hwc)) {
+	case 0x003:	return true;	/* Retired SSE/AVX FLOPs */
+	default:	return false;
+	}
+}
+
 static int amd_core_hw_config(struct perf_event *event)
 {
 	if (event->attr.exclude_host && event->attr.exclude_guest)
@@ -316,15 +339,10 @@ static int amd_core_hw_config(struct perf_event *event)
 	else if (event->attr.exclude_guest)
 		event->hw.config |= AMD64_EVENTSEL_HOSTONLY;
 
-	return 0;
-}
+	if ((x86_pmu.flags & PMU_FL_PAIR) && amd_is_pair_event_code(&event->hw))
+		event->hw.flags |= PERF_X86_EVENT_PAIR;
 
-/*
- * AMD64 events are detected based on their event codes.
- */
-static inline unsigned int amd_get_event_code(struct hw_perf_event *hwc)
-{
-	return ((hwc->config >> 24) & 0x0f00) | (hwc->config & 0x00ff);
+	return 0;
 }
 
 static inline int amd_is_nb_event(struct hw_perf_event *hwc)
@@ -855,6 +873,29 @@ amd_get_event_constraints_f15h(struct cpu_hw_events *cpuc, int idx,
 	}
 }
 
+static struct event_constraint pair_constraint;
+
+static struct event_constraint *
+amd_get_event_constraints_f17h(struct cpu_hw_events *cpuc, int idx,
+			       struct perf_event *event)
+{
+	struct hw_perf_event *hwc = &event->hw;
+
+	if (amd_is_pair_event_code(hwc))
+		return &pair_constraint;
+
+	return &unconstrained;
+}
+
+static void amd_put_event_constraints_f17h(struct cpu_hw_events *cpuc,
+					   struct perf_event *event)
+{
+	struct hw_perf_event *hwc = &event->hw;
+
+	if (is_counter_pair(hwc))
+		--cpuc->n_pair;
+}
+
 static ssize_t amd_event_sysfs_show(char *page, u64 config)
 {
 	u64 event = (config & ARCH_PERFMON_EVENTSEL_EVENT) |
@@ -898,33 +939,15 @@ static __initconst const struct x86_pmu amd_pmu = {
 
 static int __init amd_core_pmu_init(void)
 {
+	u64 even_ctr_mask = 0ULL;
+	int i;
+
 	if (!boot_cpu_has(X86_FEATURE_PERFCTR_CORE))
 		return 0;
 
-	/* Avoid calulating the value each time in the NMI handler */
+	/* Avoid calculating the value each time in the NMI handler */
 	perf_nmi_window = msecs_to_jiffies(100);
 
-	switch (boot_cpu_data.x86) {
-	case 0x15:
-		pr_cont("Fam15h ");
-		x86_pmu.get_event_constraints = amd_get_event_constraints_f15h;
-		break;
-	case 0x17:
-		pr_cont("Fam17h ");
-		/*
-		 * In family 17h, there are no event constraints in the PMC hardware.
-		 * We fallback to using default amd_get_event_constraints.
-		 */
-		break;
-	case 0x18:
-		pr_cont("Fam18h ");
-		/* Using default amd_get_event_constraints. */
-		break;
-	default:
-		pr_err("core perfctr but no constraints; unknown hardware!\n");
-		return -ENODEV;
-	}
-
 	/*
 	 * If core performance counter extensions exists, we must use
 	 * MSR_F15H_PERF_CTL/MSR_F15H_PERF_CTR msrs. See also
@@ -939,6 +962,32 @@ static int __init amd_core_pmu_init(void)
 	 */
 	x86_pmu.amd_nb_constraints = 0;
 
+	if (boot_cpu_data.x86 == 0x15) {
+		pr_cont("Fam15h ");
+		x86_pmu.get_event_constraints = amd_get_event_constraints_f15h;
+	}
+	if (boot_cpu_data.x86 >= 0x17) {
+		pr_cont("Fam17h+ ");
+		/*
+		 * Family 17h and compatibles have constraints for Large
+		 * Increment per Cycle events: they may only be assigned an
+		 * even numbered counter that has a consecutive adjacent odd
+		 * numbered counter following it.
+		 */
+		for (i = 0; i < x86_pmu.num_counters - 1; i += 2)
+			even_ctr_mask |= 1 << i;
+
+		pair_constraint = (struct event_constraint)
+				    __EVENT_CONSTRAINT(0, even_ctr_mask, 0,
+				    x86_pmu.num_counters / 2, 0,
+				    PERF_X86_EVENT_PAIR);
+
+		x86_pmu.get_event_constraints = amd_get_event_constraints_f17h;
+		x86_pmu.put_event_constraints = amd_put_event_constraints_f17h;
+		x86_pmu.perf_ctr_pair_en = AMD_MERGE_EVENT_ENABLE;
+		x86_pmu.flags |= PMU_FL_PAIR;
+	}
+
 	pr_cont("core perfctr, ");
 	return 0;
 }