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perf/x86/intel: Reduce lbr_sel_map[] size
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The index of lbr_sel_map is bit value of perf branch_sample_type.
PERF_SAMPLE_BRANCH_MAX is 1024 at present, so each lbr_sel_map uses
4096 bytes. By using bit shift as index, we can reduce lbr_sel_map
size to 40 bytes. This patch defines 'bit shift' for branch types,
and use 'bit shift' to define lbr_sel_maps.

Signed-off-by: Yan, Zheng <zheng.z.yan@intel.com>
Signed-off-by: Kan Liang <kan.liang@intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Stephane Eranian <eranian@google.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Cc: jolsa@redhat.com
Cc: linux-api@vger.kernel.org
Link: http://lkml.kernel.org/r/1415156173-10035-2-git-send-email-kan.liang@intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
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Yan, Zheng authored and Ingo Molnar committed Feb 18, 2015
1 parent c796b20 commit 27ac905
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Showing 3 changed files with 64 additions and 43 deletions.
4 changes: 4 additions & 0 deletions arch/x86/kernel/cpu/perf_event.h
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Original file line number Diff line number Diff line change
Expand Up @@ -515,6 +515,10 @@ struct x86_pmu {
struct perf_guest_switch_msr *(*guest_get_msrs)(int *nr);
};

enum {
PERF_SAMPLE_BRANCH_SELECT_MAP_SIZE = PERF_SAMPLE_BRANCH_MAX_SHIFT,
};

#define x86_add_quirk(func_) \
do { \
static struct x86_pmu_quirk __quirk __initdata = { \
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54 changes: 25 additions & 29 deletions arch/x86/kernel/cpu/perf_event_intel_lbr.c
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Original file line number Diff line number Diff line change
Expand Up @@ -69,10 +69,6 @@ static enum {
#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; \
(x) < PERF_SAMPLE_BRANCH_MAX; (x) <<= 1)

/*
* x86control flow change classification
* x86control flow changes include branches, interrupts, traps, faults
Expand Down Expand Up @@ -403,14 +399,14 @@ static int intel_pmu_setup_hw_lbr_filter(struct perf_event *event)
{
struct hw_perf_event_extra *reg;
u64 br_type = event->attr.branch_sample_type;
u64 mask = 0, m;
u64 v;
u64 mask = 0, v;
int i;

for_each_branch_sample_type(m) {
if (!(br_type & m))
for (i = 0; i < PERF_SAMPLE_BRANCH_SELECT_MAP_SIZE; i++) {
if (!(br_type & (1ULL << i)))
continue;

v = x86_pmu.lbr_sel_map[m];
v = x86_pmu.lbr_sel_map[i];
if (v == LBR_NOT_SUPP)
return -EOPNOTSUPP;

Expand Down Expand Up @@ -678,35 +674,35 @@ intel_pmu_lbr_filter(struct cpu_hw_events *cpuc)
/*
* Map interface branch filters onto LBR filters
*/
static const int nhm_lbr_sel_map[PERF_SAMPLE_BRANCH_MAX] = {
[PERF_SAMPLE_BRANCH_ANY] = LBR_ANY,
[PERF_SAMPLE_BRANCH_USER] = LBR_USER,
[PERF_SAMPLE_BRANCH_KERNEL] = LBR_KERNEL,
[PERF_SAMPLE_BRANCH_HV] = LBR_IGN,
[PERF_SAMPLE_BRANCH_ANY_RETURN] = LBR_RETURN | LBR_REL_JMP
| LBR_IND_JMP | LBR_FAR,
static const int nhm_lbr_sel_map[PERF_SAMPLE_BRANCH_SELECT_MAP_SIZE] = {
[PERF_SAMPLE_BRANCH_ANY_SHIFT] = LBR_ANY,
[PERF_SAMPLE_BRANCH_USER_SHIFT] = LBR_USER,
[PERF_SAMPLE_BRANCH_KERNEL_SHIFT] = LBR_KERNEL,
[PERF_SAMPLE_BRANCH_HV_SHIFT] = LBR_IGN,
[PERF_SAMPLE_BRANCH_ANY_RETURN_SHIFT] = LBR_RETURN | LBR_REL_JMP
| LBR_IND_JMP | LBR_FAR,
/*
* NHM/WSM erratum: must include REL_JMP+IND_JMP to get CALL branches
*/
[PERF_SAMPLE_BRANCH_ANY_CALL] =
[PERF_SAMPLE_BRANCH_ANY_CALL_SHIFT] =
LBR_REL_CALL | LBR_IND_CALL | LBR_REL_JMP | LBR_IND_JMP | LBR_FAR,
/*
* 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,
[PERF_SAMPLE_BRANCH_IND_CALL_SHIFT] = LBR_IND_CALL | LBR_IND_JMP,
[PERF_SAMPLE_BRANCH_COND_SHIFT] = LBR_JCC,
};

static const int snb_lbr_sel_map[PERF_SAMPLE_BRANCH_MAX] = {
[PERF_SAMPLE_BRANCH_ANY] = LBR_ANY,
[PERF_SAMPLE_BRANCH_USER] = LBR_USER,
[PERF_SAMPLE_BRANCH_KERNEL] = LBR_KERNEL,
[PERF_SAMPLE_BRANCH_HV] = LBR_IGN,
[PERF_SAMPLE_BRANCH_ANY_RETURN] = LBR_RETURN | LBR_FAR,
[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,
static const int snb_lbr_sel_map[PERF_SAMPLE_BRANCH_SELECT_MAP_SIZE] = {
[PERF_SAMPLE_BRANCH_ANY_SHIFT] = LBR_ANY,
[PERF_SAMPLE_BRANCH_USER_SHIFT] = LBR_USER,
[PERF_SAMPLE_BRANCH_KERNEL_SHIFT] = LBR_KERNEL,
[PERF_SAMPLE_BRANCH_HV_SHIFT] = LBR_IGN,
[PERF_SAMPLE_BRANCH_ANY_RETURN_SHIFT] = LBR_RETURN | LBR_FAR,
[PERF_SAMPLE_BRANCH_ANY_CALL_SHIFT] = LBR_REL_CALL | LBR_IND_CALL
| LBR_FAR,
[PERF_SAMPLE_BRANCH_IND_CALL_SHIFT] = LBR_IND_CALL,
[PERF_SAMPLE_BRANCH_COND_SHIFT] = LBR_JCC,
};

/* core */
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49 changes: 35 additions & 14 deletions include/uapi/linux/perf_event.h
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Original file line number Diff line number Diff line change
Expand Up @@ -152,21 +152,42 @@ enum perf_event_sample_format {
* The branch types can be combined, however BRANCH_ANY covers all types
* of branches and therefore it supersedes all the other types.
*/
enum perf_branch_sample_type_shift {
PERF_SAMPLE_BRANCH_USER_SHIFT = 0, /* user branches */
PERF_SAMPLE_BRANCH_KERNEL_SHIFT = 1, /* kernel branches */
PERF_SAMPLE_BRANCH_HV_SHIFT = 2, /* hypervisor branches */

PERF_SAMPLE_BRANCH_ANY_SHIFT = 3, /* any branch types */
PERF_SAMPLE_BRANCH_ANY_CALL_SHIFT = 4, /* any call branch */
PERF_SAMPLE_BRANCH_ANY_RETURN_SHIFT = 5, /* any return branch */
PERF_SAMPLE_BRANCH_IND_CALL_SHIFT = 6, /* indirect calls */
PERF_SAMPLE_BRANCH_ABORT_TX_SHIFT = 7, /* transaction aborts */
PERF_SAMPLE_BRANCH_IN_TX_SHIFT = 8, /* in transaction */
PERF_SAMPLE_BRANCH_NO_TX_SHIFT = 9, /* not in transaction */
PERF_SAMPLE_BRANCH_COND_SHIFT = 10, /* conditional branches */

PERF_SAMPLE_BRANCH_MAX_SHIFT /* non-ABI */
};

enum perf_branch_sample_type {
PERF_SAMPLE_BRANCH_USER = 1U << 0, /* user branches */
PERF_SAMPLE_BRANCH_KERNEL = 1U << 1, /* kernel branches */
PERF_SAMPLE_BRANCH_HV = 1U << 2, /* hypervisor branches */

PERF_SAMPLE_BRANCH_ANY = 1U << 3, /* any branch types */
PERF_SAMPLE_BRANCH_ANY_CALL = 1U << 4, /* any call branch */
PERF_SAMPLE_BRANCH_ANY_RETURN = 1U << 5, /* any return branch */
PERF_SAMPLE_BRANCH_IND_CALL = 1U << 6, /* indirect calls */
PERF_SAMPLE_BRANCH_ABORT_TX = 1U << 7, /* transaction aborts */
PERF_SAMPLE_BRANCH_IN_TX = 1U << 8, /* in transaction */
PERF_SAMPLE_BRANCH_NO_TX = 1U << 9, /* not in transaction */
PERF_SAMPLE_BRANCH_COND = 1U << 10, /* conditional branches */

PERF_SAMPLE_BRANCH_MAX = 1U << 11, /* non-ABI */
PERF_SAMPLE_BRANCH_USER = 1U << PERF_SAMPLE_BRANCH_USER_SHIFT,
PERF_SAMPLE_BRANCH_KERNEL = 1U << PERF_SAMPLE_BRANCH_KERNEL_SHIFT,
PERF_SAMPLE_BRANCH_HV = 1U << PERF_SAMPLE_BRANCH_HV_SHIFT,

PERF_SAMPLE_BRANCH_ANY = 1U << PERF_SAMPLE_BRANCH_ANY_SHIFT,
PERF_SAMPLE_BRANCH_ANY_CALL =
1U << PERF_SAMPLE_BRANCH_ANY_CALL_SHIFT,
PERF_SAMPLE_BRANCH_ANY_RETURN =
1U << PERF_SAMPLE_BRANCH_ANY_RETURN_SHIFT,
PERF_SAMPLE_BRANCH_IND_CALL =
1U << PERF_SAMPLE_BRANCH_IND_CALL_SHIFT,
PERF_SAMPLE_BRANCH_ABORT_TX =
1U << PERF_SAMPLE_BRANCH_ABORT_TX_SHIFT,
PERF_SAMPLE_BRANCH_IN_TX = 1U << PERF_SAMPLE_BRANCH_IN_TX_SHIFT,
PERF_SAMPLE_BRANCH_NO_TX = 1U << PERF_SAMPLE_BRANCH_NO_TX_SHIFT,
PERF_SAMPLE_BRANCH_COND = 1U << PERF_SAMPLE_BRANCH_COND_SHIFT,

PERF_SAMPLE_BRANCH_MAX = 1U << PERF_SAMPLE_BRANCH_MAX_SHIFT,
};

#define PERF_SAMPLE_BRANCH_PLM_ALL \
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