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Diffstat (limited to 'arch/x86/kernel/cpu/perf_event_intel_lbr.c')
-rw-r--r--arch/x86/kernel/cpu/perf_event_intel_lbr.c102
1 files changed, 88 insertions, 14 deletions
diff --git a/arch/x86/kernel/cpu/perf_event_intel_lbr.c b/arch/x86/kernel/cpu/perf_event_intel_lbr.c
index da02e9cc375..9dd2459a4c7 100644
--- a/arch/x86/kernel/cpu/perf_event_intel_lbr.c
+++ b/arch/x86/kernel/cpu/perf_event_intel_lbr.c
@@ -12,6 +12,16 @@ enum {
LBR_FORMAT_LIP = 0x01,
LBR_FORMAT_EIP = 0x02,
LBR_FORMAT_EIP_FLAGS = 0x03,
+ LBR_FORMAT_EIP_FLAGS2 = 0x04,
+ LBR_FORMAT_MAX_KNOWN = LBR_FORMAT_EIP_FLAGS2,
+};
+
+static enum {
+ LBR_EIP_FLAGS = 1,
+ LBR_TSX = 2,
+} lbr_desc[LBR_FORMAT_MAX_KNOWN + 1] = {
+ [LBR_FORMAT_EIP_FLAGS] = LBR_EIP_FLAGS,
+ [LBR_FORMAT_EIP_FLAGS2] = LBR_EIP_FLAGS | LBR_TSX,
};
/*
@@ -56,6 +66,8 @@ enum {
LBR_FAR)
#define LBR_FROM_FLAG_MISPRED (1ULL << 63)
+#define LBR_FROM_FLAG_IN_TX (1ULL << 62)
+#define LBR_FROM_FLAG_ABORT (1ULL << 61)
#define for_each_branch_sample_type(x) \
for ((x) = PERF_SAMPLE_BRANCH_USER; \
@@ -81,9 +93,13 @@ enum {
X86_BR_JMP = 1 << 9, /* jump */
X86_BR_IRQ = 1 << 10,/* hw interrupt or trap or fault */
X86_BR_IND_CALL = 1 << 11,/* indirect calls */
+ X86_BR_ABORT = 1 << 12,/* transaction abort */
+ X86_BR_IN_TX = 1 << 13,/* in transaction */
+ X86_BR_NO_TX = 1 << 14,/* not in transaction */
};
#define X86_BR_PLM (X86_BR_USER | X86_BR_KERNEL)
+#define X86_BR_ANYTX (X86_BR_NO_TX | X86_BR_IN_TX)
#define X86_BR_ANY \
(X86_BR_CALL |\
@@ -95,6 +111,7 @@ enum {
X86_BR_JCC |\
X86_BR_JMP |\
X86_BR_IRQ |\
+ X86_BR_ABORT |\
X86_BR_IND_CALL)
#define X86_BR_ALL (X86_BR_PLM | X86_BR_ANY)
@@ -267,27 +284,50 @@ static void intel_pmu_lbr_read_64(struct cpu_hw_events *cpuc)
int lbr_format = x86_pmu.intel_cap.lbr_format;
u64 tos = intel_pmu_lbr_tos();
int i;
+ int out = 0;
for (i = 0; i < x86_pmu.lbr_nr; i++) {
unsigned long lbr_idx = (tos - i) & mask;
- u64 from, to, mis = 0, pred = 0;
+ u64 from, to, mis = 0, pred = 0, in_tx = 0, abort = 0;
+ int skip = 0;
+ int lbr_flags = lbr_desc[lbr_format];
rdmsrl(x86_pmu.lbr_from + lbr_idx, from);
rdmsrl(x86_pmu.lbr_to + lbr_idx, to);
- if (lbr_format == LBR_FORMAT_EIP_FLAGS) {
+ if (lbr_flags & LBR_EIP_FLAGS) {
mis = !!(from & LBR_FROM_FLAG_MISPRED);
pred = !mis;
- from = (u64)((((s64)from) << 1) >> 1);
+ skip = 1;
+ }
+ if (lbr_flags & LBR_TSX) {
+ in_tx = !!(from & LBR_FROM_FLAG_IN_TX);
+ abort = !!(from & LBR_FROM_FLAG_ABORT);
+ skip = 3;
}
+ from = (u64)((((s64)from) << skip) >> skip);
- cpuc->lbr_entries[i].from = from;
- cpuc->lbr_entries[i].to = to;
- cpuc->lbr_entries[i].mispred = mis;
- cpuc->lbr_entries[i].predicted = pred;
- cpuc->lbr_entries[i].reserved = 0;
+ /*
+ * Some CPUs report duplicated abort records,
+ * with the second entry not having an abort bit set.
+ * Skip them here. This loop runs backwards,
+ * so we need to undo the previous record.
+ * If the abort just happened outside the window
+ * the extra entry cannot be removed.
+ */
+ if (abort && x86_pmu.lbr_double_abort && out > 0)
+ out--;
+
+ cpuc->lbr_entries[out].from = from;
+ cpuc->lbr_entries[out].to = to;
+ cpuc->lbr_entries[out].mispred = mis;
+ cpuc->lbr_entries[out].predicted = pred;
+ cpuc->lbr_entries[out].in_tx = in_tx;
+ cpuc->lbr_entries[out].abort = abort;
+ cpuc->lbr_entries[out].reserved = 0;
+ out++;
}
- cpuc->lbr_stack.nr = i;
+ cpuc->lbr_stack.nr = out;
}
void intel_pmu_lbr_read(void)
@@ -334,6 +374,19 @@ static void intel_pmu_setup_sw_lbr_filter(struct perf_event *event)
if (br_type & PERF_SAMPLE_BRANCH_IND_CALL)
mask |= X86_BR_IND_CALL;
+
+ if (br_type & PERF_SAMPLE_BRANCH_ABORT_TX)
+ mask |= X86_BR_ABORT;
+
+ if (br_type & PERF_SAMPLE_BRANCH_IN_TX)
+ mask |= X86_BR_IN_TX;
+
+ if (br_type & PERF_SAMPLE_BRANCH_NO_TX)
+ mask |= X86_BR_NO_TX;
+
+ if (br_type & PERF_SAMPLE_BRANCH_COND)
+ mask |= X86_BR_JCC;
+
/*
* stash actual user request into reg, it may
* be used by fixup code for some CPU
@@ -408,7 +461,7 @@ int intel_pmu_setup_lbr_filter(struct perf_event *event)
* decoded (e.g., text page not present), then X86_BR_NONE is
* returned.
*/
-static int branch_type(unsigned long from, unsigned long to)
+static int branch_type(unsigned long from, unsigned long to, int abort)
{
struct insn insn;
void *addr;
@@ -428,6 +481,9 @@ static int branch_type(unsigned long from, unsigned long to)
if (from == 0 || to == 0)
return X86_BR_NONE;
+ if (abort)
+ return X86_BR_ABORT | to_plm;
+
if (from_plm == X86_BR_USER) {
/*
* can happen if measuring at the user level only
@@ -438,12 +494,22 @@ static int branch_type(unsigned long from, unsigned long to)
/* may fail if text not present */
bytes = copy_from_user_nmi(buf, (void __user *)from, size);
- if (bytes != size)
+ if (bytes != 0)
return X86_BR_NONE;
addr = buf;
- } else
- addr = (void *)from;
+ } else {
+ /*
+ * The LBR logs any address in the IP, even if the IP just
+ * faulted. This means userspace can control the from address.
+ * Ensure we don't blindy read any address by validating it is
+ * a known text address.
+ */
+ if (kernel_text_address(from))
+ addr = (void *)from;
+ else
+ return X86_BR_NONE;
+ }
/*
* decoder needs to know the ABI especially
@@ -564,7 +630,13 @@ intel_pmu_lbr_filter(struct cpu_hw_events *cpuc)
from = cpuc->lbr_entries[i].from;
to = cpuc->lbr_entries[i].to;
- type = branch_type(from, to);
+ type = branch_type(from, to, cpuc->lbr_entries[i].abort);
+ if (type != X86_BR_NONE && (br_sel & X86_BR_ANYTX)) {
+ if (cpuc->lbr_entries[i].in_tx)
+ type |= X86_BR_IN_TX;
+ else
+ type |= X86_BR_NO_TX;
+ }
/* if type does not correspond, then discard */
if (type == X86_BR_NONE || (br_sel & type) != type) {
@@ -609,6 +681,7 @@ static const int nhm_lbr_sel_map[PERF_SAMPLE_BRANCH_MAX] = {
* NHM/WSM erratum: must include IND_JMP to capture IND_CALL
*/
[PERF_SAMPLE_BRANCH_IND_CALL] = LBR_IND_CALL | LBR_IND_JMP,
+ [PERF_SAMPLE_BRANCH_COND] = LBR_JCC,
};
static const int snb_lbr_sel_map[PERF_SAMPLE_BRANCH_MAX] = {
@@ -620,6 +693,7 @@ static const int snb_lbr_sel_map[PERF_SAMPLE_BRANCH_MAX] = {
[PERF_SAMPLE_BRANCH_ANY_CALL] = LBR_REL_CALL | LBR_IND_CALL
| LBR_FAR,
[PERF_SAMPLE_BRANCH_IND_CALL] = LBR_IND_CALL,
+ [PERF_SAMPLE_BRANCH_COND] = LBR_JCC,
};
/* core */
generated by cgit v1.2.3-70-g09d2 (git 2.46.0) at 2025-11-09 21:03:43 +0000