Power management fixes for 4.20-rc4

- Fix tasks freezer deadlock in de_thread() that occurs if one
    of its sub-threads has been frozen already (Chanho Min).
 
  - Avoid registering a platform device by the ti-cpufreq driver
    on platforms that cannot use it (Dave Gerlach).
 
  - Fix a mistake in the ti-opp-supply operating performance points
    (OPP) driver that caused an incorrect reference voltage to be
    used and make it adjust the minimum voltage dynamically to avoid
    hangs or crashes in some cases (Keerthy).
 
  - Fix issues related to compiler flags in the cpupower utility
    and correct a linking problem in it by renaming a file with
    a duplicate name (Jiri Olsa, Konstantin Khlebnikov).
 -----BEGIN PGP SIGNATURE-----
 Version: GnuPG v2
 
 iQIcBAABCAAGBQJb99ANAAoJEILEb/54YlRxUk4QAIkpXmLdEm0zvQXJZKJxuxu/
 8eiglPcoCAAVgR3uRjezTyQeFCDjqGIqmpiipFOkxgAaeb+aiFta2B88B4oZ3OAf
 G5yJG4CMs5+Tp/oH2+McX4PMo2WfoEIDoOGVOdtlk4iGAIh9tT5KvNfCUyxHLP7c
 cFjdeUQuc8PRPzutESxYHB23FmECCEprVmEFVckQ7vSCnWX6dm1mFteCiNZADH8/
 YNgRWRYtyWXlPRNCPJuCvYmVHLgm0Tw6CVhG4ttXT9wIkYyiLK9Flx9X6gsBWdoS
 ej1jbJM7R/EAUzHvCjUCSfMKDNWvQySR3gC2m0vG5Goext2UXWieSHaI6BfqjPP2
 wTBX9lAKu3iIGISoorjJZAMe4v26Tpbs0v5ApsOGr50WNZKZtRkBwaJ0EFT2hEa8
 MsDtUjr+d7CIQ+ZDHmAbOzghpDlSuhGypfkD7IPtA/AY1dy1wJ3BUYya8ucqSdr3
 iKkQcndN3ASR1+Fyb3c1cflh9fWe84aeSmYPihcX2m+/D43keYXbj2ANdCH1dF3E
 cwAXw9+VteUQ1tihqgJapFogK3VphMbRErPSGXryuyiMxr38g7tgHAd2rId0JG4g
 QftqpZa19aEed8tJNaQWWjBaBFgYeAT9BQqcP6CjFOO9klPH//NSiqzQUFMdzsEc
 Qql1V/aoOIsflb7gJH3/
 =JQxr
 -----END PGP SIGNATURE-----

Merge tag 'pm-4.20-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm

Pull power management fixes from Rafael Wysocki:
 "These fix two issues in the Operating Performance Points (OPP)
  framework, one cpufreq driver issue, one problem related to the tasks
  freezer and a few build-related issues in the cpupower utility.

  Specifics:

   - Fix tasks freezer deadlock in de_thread() that occurs if one of its
     sub-threads has been frozen already (Chanho Min).

   - Avoid registering a platform device by the ti-cpufreq driver on
     platforms that cannot use it (Dave Gerlach).

   - Fix a mistake in the ti-opp-supply operating performance points
     (OPP) driver that caused an incorrect reference voltage to be used
     and make it adjust the minimum voltage dynamically to avoid hangs
     or crashes in some cases (Keerthy).

   - Fix issues related to compiler flags in the cpupower utility and
     correct a linking problem in it by renaming a file with a duplicate
     name (Jiri Olsa, Konstantin Khlebnikov)"

* tag 'pm-4.20-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
  exec: make de_thread() freezable
  cpufreq: ti-cpufreq: Only register platform_device when supported
  opp: ti-opp-supply: Correct the supply in _get_optimal_vdd_voltage call
  opp: ti-opp-supply: Dynamically update u_volt_min
  tools cpupower: Override CFLAGS assignments
  tools cpupower debug: Allow to use outside build flags
  tools/power/cpupower: fix compilation with STATIC=true

drivers/cpufreq/ti-cpufreq.c

@@ -201,19 +201,28 @@ static const struct of_device_id ti_cpufreq_of_match[] = {
 	{},
 };
 
+static const struct of_device_id *ti_cpufreq_match_node(void)
+{
+	struct device_node *np;
+	const struct of_device_id *match;
+
+	np = of_find_node_by_path("/");
+	match = of_match_node(ti_cpufreq_of_match, np);
+	of_node_put(np);
+
+	return match;
+}
+
 static int ti_cpufreq_probe(struct platform_device *pdev)
 {
 	u32 version[VERSION_COUNT];
-	struct device_node *np;
 	const struct of_device_id *match;
 	struct opp_table *ti_opp_table;
 	struct ti_cpufreq_data *opp_data;
 	const char * const reg_names[] = {"vdd", "vbb"};
 	int ret;
 
-	np = of_find_node_by_path("/");
-	match = of_match_node(ti_cpufreq_of_match, np);
-	of_node_put(np);
+	match = dev_get_platdata(&pdev->dev);
 	if (!match)
 		return -ENODEV;
 
@@ -290,7 +299,14 @@ fail_put_node:
 
 static int ti_cpufreq_init(void)
 {
-	platform_device_register_simple("ti-cpufreq", -1, NULL, 0);
+	const struct of_device_id *match;
+
+	/* Check to ensure we are on a compatible platform */
+	match = ti_cpufreq_match_node();
+	if (match)
+		platform_device_register_data(NULL, "ti-cpufreq", -1, match,
+					      sizeof(*match));
+
 	return 0;
 }
 module_init(ti_cpufreq_init);

drivers/opp/ti-opp-supply.c

@@ -288,7 +288,10 @@ static int ti_opp_supply_set_opp(struct dev_pm_set_opp_data *data)
 	int ret;
 
 	vdd_uv = _get_optimal_vdd_voltage(dev, &opp_data,
-					  new_supply_vbb->u_volt);
+					  new_supply_vdd->u_volt);
+
+	if (new_supply_vdd->u_volt_min < vdd_uv)
+		new_supply_vdd->u_volt_min = vdd_uv;
 
 	/* Scaling up? Scale voltage before frequency */
 	if (freq > old_freq) {

fs/exec.c

@@ -62,6 +62,7 @@
 #include <linux/oom.h>
 #include <linux/compat.h>
 #include <linux/vmalloc.h>
+#include <linux/freezer.h>
 
 #include <linux/uaccess.h>
 #include <asm/mmu_context.h>
@@ -1083,7 +1084,7 @@ static int de_thread(struct task_struct *tsk)
 	while (sig->notify_count) {
 		__set_current_state(TASK_KILLABLE);
 		spin_unlock_irq(lock);
-		schedule();
+		freezable_schedule();
 		if (unlikely(__fatal_signal_pending(tsk)))
 			goto killed;
 		spin_lock_irq(lock);
@@ -1111,7 +1112,7 @@ static int de_thread(struct task_struct *tsk)
 			__set_current_state(TASK_KILLABLE);
 			write_unlock_irq(&tasklist_lock);
 			cgroup_threadgroup_change_end(tsk);
-			schedule();
+			freezable_schedule();
 			if (unlikely(__fatal_signal_pending(tsk)))
 				goto killed;
 		}

tools/power/cpupower/Makefile

@@ -129,7 +129,7 @@ WARNINGS += $(call cc-supports,-Wno-pointer-sign)
 WARNINGS += $(call cc-supports,-Wdeclaration-after-statement)
 WARNINGS += -Wshadow
 
-CFLAGS += -DVERSION=\"$(VERSION)\" -DPACKAGE=\"$(PACKAGE)\" \
+override CFLAGS += -DVERSION=\"$(VERSION)\" -DPACKAGE=\"$(PACKAGE)\" \
 		-DPACKAGE_BUGREPORT=\"$(PACKAGE_BUGREPORT)\" -D_GNU_SOURCE
 
 UTIL_OBJS =  utils/helpers/amd.o utils/helpers/msr.o \
@@ -156,12 +156,12 @@ LIB_SRC = 	lib/cpufreq.c lib/cpupower.c lib/cpuidle.c
 LIB_OBJS = 	lib/cpufreq.o lib/cpupower.o lib/cpuidle.o
 LIB_OBJS :=	$(addprefix $(OUTPUT),$(LIB_OBJS))
 
-CFLAGS +=	-pipe
+override CFLAGS +=	-pipe
 
 ifeq ($(strip $(NLS)),true)
 	INSTALL_NLS += install-gmo
 	COMPILE_NLS += create-gmo
-	CFLAGS += -DNLS
+	override CFLAGS += -DNLS
 endif
 
 ifeq ($(strip $(CPUFREQ_BENCH)),true)
@@ -175,7 +175,7 @@ ifeq ($(strip $(STATIC)),true)
         UTIL_SRC += $(LIB_SRC)
 endif
 
-CFLAGS += $(WARNINGS)
+override CFLAGS += $(WARNINGS)
 
 ifeq ($(strip $(V)),false)
 	QUIET=@
@@ -188,10 +188,10 @@ export QUIET ECHO
 
 # if DEBUG is enabled, then we do not strip or optimize
 ifeq ($(strip $(DEBUG)),true)
-	CFLAGS += -O1 -g -DDEBUG
+	override CFLAGS += -O1 -g -DDEBUG
 	STRIPCMD = /bin/true -Since_we_are_debugging
 else
-	CFLAGS += $(OPTIMIZATION) -fomit-frame-pointer
+	override CFLAGS += $(OPTIMIZATION) -fomit-frame-pointer
 	STRIPCMD = $(STRIP) -s --remove-section=.note --remove-section=.comment
 endif
 

tools/power/cpupower/bench/Makefile

@@ -9,7 +9,7 @@ endif
 ifeq ($(strip $(STATIC)),true)
 LIBS = -L../ -L$(OUTPUT) -lm
 OBJS = $(OUTPUT)main.o $(OUTPUT)parse.o $(OUTPUT)system.o $(OUTPUT)benchmark.o \
-       $(OUTPUT)../lib/cpufreq.o $(OUTPUT)../lib/sysfs.o
+       $(OUTPUT)../lib/cpufreq.o $(OUTPUT)../lib/cpupower.o
 else
 LIBS = -L../ -L$(OUTPUT) -lm -lcpupower
 OBJS = $(OUTPUT)main.o $(OUTPUT)parse.o $(OUTPUT)system.o $(OUTPUT)benchmark.o

tools/power/cpupower/debug/x86_64/Makefile

@@ -13,10 +13,10 @@ INSTALL = /usr/bin/install
 default: all
 
 $(OUTPUT)centrino-decode: ../i386/centrino-decode.c
-	$(CC) $(CFLAGS) -o $@ $<
+	$(CC) $(CFLAGS) -o $@ $(LDFLAGS) $<
 
 $(OUTPUT)powernow-k8-decode: ../i386/powernow-k8-decode.c
-	$(CC) $(CFLAGS) -o $@ $<
+	$(CC) $(CFLAGS) -o $@ $(LDFLAGS) $<
 
 all: $(OUTPUT)centrino-decode $(OUTPUT)powernow-k8-decode
 

tools/power/cpupower/lib/cpufreq.c

@@ -28,7 +28,7 @@ static unsigned int sysfs_cpufreq_read_file(unsigned int cpu, const char *fname,
 
 	snprintf(path, sizeof(path), PATH_TO_CPU "cpu%u/cpufreq/%s",
 			 cpu, fname);
-	return sysfs_read_file(path, buf, buflen);
+	return cpupower_read_sysfs(path, buf, buflen);
 }
 
 /* helper function to write a new value to a /sys file */

tools/power/cpupower/lib/cpuidle.c

@@ -319,7 +319,7 @@ static unsigned int sysfs_cpuidle_read_file(const char *fname, char *buf,
 
 	snprintf(path, sizeof(path), PATH_TO_CPU "cpuidle/%s", fname);
 
-	return sysfs_read_file(path, buf, buflen);
+	return cpupower_read_sysfs(path, buf, buflen);
 }
 
 

tools/power/cpupower/lib/cpupower.c

@@ -15,7 +15,7 @@
 #include "cpupower.h"
 #include "cpupower_intern.h"
 
-unsigned int sysfs_read_file(const char *path, char *buf, size_t buflen)
+unsigned int cpupower_read_sysfs(const char *path, char *buf, size_t buflen)
 {
 	int fd;
 	ssize_t numread;
@@ -95,7 +95,7 @@ static int sysfs_topology_read_file(unsigned int cpu, const char *fname, int *re
 
 	snprintf(path, sizeof(path), PATH_TO_CPU "cpu%u/topology/%s",
 			 cpu, fname);
-	if (sysfs_read_file(path, linebuf, MAX_LINE_LEN) == 0)
+	if (cpupower_read_sysfs(path, linebuf, MAX_LINE_LEN) == 0)
 		return -1;
 	*result = strtol(linebuf, &endp, 0);
 	if (endp == linebuf || errno == ERANGE)

tools/power/cpupower/lib/cpupower_intern.h

@@ -3,4 +3,4 @@
 #define MAX_LINE_LEN 4096
 #define SYSFS_PATH_MAX 255
 
-unsigned int sysfs_read_file(const char *path, char *buf, size_t buflen);
+unsigned int cpupower_read_sysfs(const char *path, char *buf, size_t buflen);