Commit b3ea36b7 authored by Linus Torvalds's avatar Linus Torvalds

Merge branch 'perf-fixes-for-linus' of...

Merge branch 'perf-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip

* 'perf-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  kprobes/x86: Fix the return address of multiple kretprobes
  perf tools: Fix build error on read only source.
  perf, x86: Fix Intel-nhm PMU programming errata workaround
parents 763008c4 737480a0
......@@ -491,33 +491,78 @@ static void intel_pmu_enable_all(int added)
* Intel Errata AAP53 (model 30)
* Intel Errata BD53 (model 44)
*
* These chips need to be 'reset' when adding counters by programming
* the magic three (non counting) events 0x4300D2, 0x4300B1 and 0x4300B5
* either in sequence on the same PMC or on different PMCs.
* The official story:
* These chips need to be 'reset' when adding counters by programming the
* magic three (non-counting) events 0x4300B5, 0x4300D2, and 0x4300B1 either
* in sequence on the same PMC or on different PMCs.
*
* In practise it appears some of these events do in fact count, and
* we need to programm all 4 events.
*/
static void intel_pmu_nhm_enable_all(int added)
static void intel_pmu_nhm_workaround(void)
{
if (added) {
struct cpu_hw_events *cpuc = &__get_cpu_var(cpu_hw_events);
static const unsigned long nhm_magic[4] = {
0x4300B5,
0x4300D2,
0x4300B1,
0x4300B1
};
struct perf_event *event;
int i;
wrmsrl(MSR_ARCH_PERFMON_EVENTSEL0 + 0, 0x4300D2);
wrmsrl(MSR_ARCH_PERFMON_EVENTSEL0 + 1, 0x4300B1);
wrmsrl(MSR_ARCH_PERFMON_EVENTSEL0 + 2, 0x4300B5);
/*
* The Errata requires below steps:
* 1) Clear MSR_IA32_PEBS_ENABLE and MSR_CORE_PERF_GLOBAL_CTRL;
* 2) Configure 4 PERFEVTSELx with the magic events and clear
* the corresponding PMCx;
* 3) set bit0~bit3 of MSR_CORE_PERF_GLOBAL_CTRL;
* 4) Clear MSR_CORE_PERF_GLOBAL_CTRL;
* 5) Clear 4 pairs of ERFEVTSELx and PMCx;
*/
wrmsrl(MSR_CORE_PERF_GLOBAL_CTRL, 0x3);
wrmsrl(MSR_CORE_PERF_GLOBAL_CTRL, 0x0);
/*
* The real steps we choose are a little different from above.
* A) To reduce MSR operations, we don't run step 1) as they
* are already cleared before this function is called;
* B) Call x86_perf_event_update to save PMCx before configuring
* PERFEVTSELx with magic number;
* C) With step 5), we do clear only when the PERFEVTSELx is
* not used currently.
* D) Call x86_perf_event_set_period to restore PMCx;
*/
for (i = 0; i < 3; i++) {
struct perf_event *event = cpuc->events[i];
/* We always operate 4 pairs of PERF Counters */
for (i = 0; i < 4; i++) {
event = cpuc->events[i];
if (event)
x86_perf_event_update(event);
}
if (!event)
continue;
for (i = 0; i < 4; i++) {
wrmsrl(MSR_ARCH_PERFMON_EVENTSEL0 + i, nhm_magic[i]);
wrmsrl(MSR_ARCH_PERFMON_PERFCTR0 + i, 0x0);
}
wrmsrl(MSR_CORE_PERF_GLOBAL_CTRL, 0xf);
wrmsrl(MSR_CORE_PERF_GLOBAL_CTRL, 0x0);
for (i = 0; i < 4; i++) {
event = cpuc->events[i];
if (event) {
x86_perf_event_set_period(event);
__x86_pmu_enable_event(&event->hw,
ARCH_PERFMON_EVENTSEL_ENABLE);
} else
wrmsrl(MSR_ARCH_PERFMON_EVENTSEL0 + i, 0x0);
}
}
}
static void intel_pmu_nhm_enable_all(int added)
{
if (added)
intel_pmu_nhm_workaround();
intel_pmu_enable_all(added);
}
......
......@@ -709,6 +709,7 @@ static __used __kprobes void *trampoline_handler(struct pt_regs *regs)
struct hlist_node *node, *tmp;
unsigned long flags, orig_ret_address = 0;
unsigned long trampoline_address = (unsigned long)&kretprobe_trampoline;
kprobe_opcode_t *correct_ret_addr = NULL;
INIT_HLIST_HEAD(&empty_rp);
kretprobe_hash_lock(current, &head, &flags);
......@@ -740,14 +741,34 @@ static __used __kprobes void *trampoline_handler(struct pt_regs *regs)
/* another task is sharing our hash bucket */
continue;
orig_ret_address = (unsigned long)ri->ret_addr;
if (orig_ret_address != trampoline_address)
/*
* This is the real return address. Any other
* instances associated with this task are for
* other calls deeper on the call stack
*/
break;
}
kretprobe_assert(ri, orig_ret_address, trampoline_address);
correct_ret_addr = ri->ret_addr;
hlist_for_each_entry_safe(ri, node, tmp, head, hlist) {
if (ri->task != current)
/* another task is sharing our hash bucket */
continue;
orig_ret_address = (unsigned long)ri->ret_addr;
if (ri->rp && ri->rp->handler) {
__get_cpu_var(current_kprobe) = &ri->rp->kp;
get_kprobe_ctlblk()->kprobe_status = KPROBE_HIT_ACTIVE;
ri->ret_addr = correct_ret_addr;
ri->rp->handler(ri, regs);
__get_cpu_var(current_kprobe) = NULL;
}
orig_ret_address = (unsigned long)ri->ret_addr;
recycle_rp_inst(ri, &empty_rp);
if (orig_ret_address != trampoline_address)
......@@ -759,8 +780,6 @@ static __used __kprobes void *trampoline_handler(struct pt_regs *regs)
break;
}
kretprobe_assert(ri, orig_ret_address, trampoline_address);
kretprobe_hash_unlock(current, &flags);
hlist_for_each_entry_safe(ri, node, tmp, &empty_rp, hlist) {
......
......@@ -5,6 +5,12 @@ endif
# The default target of this Makefile is...
all::
ifneq ($(OUTPUT),)
# check that the output directory actually exists
OUTDIR := $(shell cd $(OUTPUT) && /bin/pwd)
$(if $(OUTDIR),, $(error output directory "$(OUTPUT)" does not exist))
endif
# Define V=1 to have a more verbose compile.
# Define V=2 to have an even more verbose compile.
#
......@@ -931,15 +937,15 @@ $(OUTPUT)common-cmds.h: $(wildcard Documentation/perf-*.txt)
$(QUIET_GEN). util/generate-cmdlist.sh > $@+ && mv $@+ $@
$(patsubst %.sh,%,$(SCRIPT_SH)) : % : %.sh
$(QUIET_GEN)$(RM) $@ $@+ && \
$(QUIET_GEN)$(RM) $(OUTPUT)$@ $(OUTPUT)$@+ && \
sed -e '1s|#!.*/sh|#!$(SHELL_PATH_SQ)|' \
-e 's|@SHELL_PATH@|$(SHELL_PATH_SQ)|' \
-e 's|@@PERL@@|$(PERL_PATH_SQ)|g' \
-e 's/@@PERF_VERSION@@/$(PERF_VERSION)/g' \
-e 's/@@NO_CURL@@/$(NO_CURL)/g' \
$@.sh >$@+ && \
chmod +x $@+ && \
mv $@+ $(OUTPUT)$@
$@.sh > $(OUTPUT)$@+ && \
chmod +x $(OUTPUT)$@+ && \
mv $(OUTPUT)$@+ $(OUTPUT)$@
configure: configure.ac
$(QUIET_GEN)$(RM) $@ $<+ && \
......
......@@ -113,7 +113,7 @@ endef
# try-cc
# Usage: option = $(call try-cc, source-to-build, cc-options)
try-cc = $(shell sh -c \
'TMP="$(TMPOUT).$$$$"; \
'TMP="$(OUTPUT)$(TMPOUT).$$$$"; \
echo "$(1)" | \
$(CC) -x c - $(2) -o "$$TMP" > /dev/null 2>&1 && echo y; \
rm -f "$$TMP"')
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