2011-08-30 23:41:05 +00:00
|
|
|
#include <linux/bitops.h>
|
|
|
|
#include <linux/types.h>
|
|
|
|
#include <linux/slab.h>
|
perf, x86: Add PEBS infrastructure
This patch implements support for Intel Precise Event Based Sampling,
which is an alternative counter mode in which the counter triggers a
hardware assist to collect information on events. The hardware assist
takes a trap like snapshot of a subset of the machine registers.
This data is written to the Intel Debug-Store, which can be programmed
with a data threshold at which to raise a PMI.
With the PEBS hardware assist being trap like, the reported IP is always
one instruction after the actual instruction that triggered the event.
This implements a simple PEBS model that always takes a single PEBS event
at a time. This is done so that the interaction with the rest of the
system is as expected (freq adjust, period randomization, lbr,
callchains, etc.).
It adds an ABI element: perf_event_attr::precise, which indicates that we
wish to use this (constrained, but precise) mode.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arnaldo Carvalho de Melo <acme@infradead.org>
Cc: paulus@samba.org
Cc: eranian@google.com
Cc: robert.richter@amd.com
Cc: fweisbec@gmail.com
LKML-Reference: <20100304140100.392111285@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-03-02 18:52:12 +00:00
|
|
|
|
2011-08-30 23:41:05 +00:00
|
|
|
#include <asm/perf_event.h>
|
2012-02-09 22:20:58 +00:00
|
|
|
#include <asm/insn.h>
|
2011-08-30 23:41:05 +00:00
|
|
|
|
|
|
|
#include "perf_event.h"
|
perf, x86: Add PEBS infrastructure
This patch implements support for Intel Precise Event Based Sampling,
which is an alternative counter mode in which the counter triggers a
hardware assist to collect information on events. The hardware assist
takes a trap like snapshot of a subset of the machine registers.
This data is written to the Intel Debug-Store, which can be programmed
with a data threshold at which to raise a PMI.
With the PEBS hardware assist being trap like, the reported IP is always
one instruction after the actual instruction that triggered the event.
This implements a simple PEBS model that always takes a single PEBS event
at a time. This is done so that the interaction with the rest of the
system is as expected (freq adjust, period randomization, lbr,
callchains, etc.).
It adds an ABI element: perf_event_attr::precise, which indicates that we
wish to use this (constrained, but precise) mode.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arnaldo Carvalho de Melo <acme@infradead.org>
Cc: paulus@samba.org
Cc: eranian@google.com
Cc: robert.richter@amd.com
Cc: fweisbec@gmail.com
LKML-Reference: <20100304140100.392111285@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-03-02 18:52:12 +00:00
|
|
|
|
|
|
|
/* The size of a BTS record in bytes: */
|
|
|
|
#define BTS_RECORD_SIZE 24
|
|
|
|
|
|
|
|
#define BTS_BUFFER_SIZE (PAGE_SIZE << 4)
|
|
|
|
#define PEBS_BUFFER_SIZE PAGE_SIZE
|
perf/x86: Optimize intel_pmu_pebs_fixup_ip()
There's been reports of high NMI handler overhead, highlighted by
such kernel messages:
[ 3697.380195] perf samples too long (10009 > 10000), lowering kernel.perf_event_max_sample_rate to 13000
[ 3697.389509] INFO: NMI handler (perf_event_nmi_handler) took too long to run: 9.331 msecs
Don Zickus analyzed the source of the overhead and reported:
> While there are a few places that are causing latencies, for now I focused on
> the longest one first. It seems to be 'copy_user_from_nmi'
>
> intel_pmu_handle_irq ->
> intel_pmu_drain_pebs_nhm ->
> __intel_pmu_drain_pebs_nhm ->
> __intel_pmu_pebs_event ->
> intel_pmu_pebs_fixup_ip ->
> copy_from_user_nmi
>
> In intel_pmu_pebs_fixup_ip(), if the while-loop goes over 50, the sum of
> all the copy_from_user_nmi latencies seems to go over 1,000,000 cycles
> (there are some cases where only 10 iterations are needed to go that high
> too, but in generall over 50 or so). At this point copy_user_from_nmi
> seems to account for over 90% of the nmi latency.
The solution to that is to avoid having to call copy_from_user_nmi() for
every instruction.
Since we already limit the max basic block size, we can easily
pre-allocate a piece of memory to copy the entire thing into in one
go.
Don reported this test result:
> Your patch made a huge difference in improvement. The
> copy_from_user_nmi() no longer hits the million of cycles. I still
> have a batch of 100,000-300,000 cycles. My longest NMI paths used
> to be dominated by copy_from_user_nmi, now it is not (I have to dig
> up the new hot path).
Reported-and-tested-by: Don Zickus <dzickus@redhat.com>
Cc: jmario@redhat.com
Cc: acme@infradead.org
Cc: dave.hansen@linux.intel.com
Cc: eranian@google.com
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20131016105755.GX10651@twins.programming.kicks-ass.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-10-15 10:14:04 +00:00
|
|
|
#define PEBS_FIXUP_SIZE PAGE_SIZE
|
perf, x86: Add PEBS infrastructure
This patch implements support for Intel Precise Event Based Sampling,
which is an alternative counter mode in which the counter triggers a
hardware assist to collect information on events. The hardware assist
takes a trap like snapshot of a subset of the machine registers.
This data is written to the Intel Debug-Store, which can be programmed
with a data threshold at which to raise a PMI.
With the PEBS hardware assist being trap like, the reported IP is always
one instruction after the actual instruction that triggered the event.
This implements a simple PEBS model that always takes a single PEBS event
at a time. This is done so that the interaction with the rest of the
system is as expected (freq adjust, period randomization, lbr,
callchains, etc.).
It adds an ABI element: perf_event_attr::precise, which indicates that we
wish to use this (constrained, but precise) mode.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arnaldo Carvalho de Melo <acme@infradead.org>
Cc: paulus@samba.org
Cc: eranian@google.com
Cc: robert.richter@amd.com
Cc: fweisbec@gmail.com
LKML-Reference: <20100304140100.392111285@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-03-02 18:52:12 +00:00
|
|
|
|
|
|
|
/*
|
|
|
|
* pebs_record_32 for p4 and core not supported
|
|
|
|
|
|
|
|
struct pebs_record_32 {
|
|
|
|
u32 flags, ip;
|
|
|
|
u32 ax, bc, cx, dx;
|
|
|
|
u32 si, di, bp, sp;
|
|
|
|
};
|
|
|
|
|
|
|
|
*/
|
|
|
|
|
2013-01-24 15:10:32 +00:00
|
|
|
union intel_x86_pebs_dse {
|
|
|
|
u64 val;
|
|
|
|
struct {
|
|
|
|
unsigned int ld_dse:4;
|
|
|
|
unsigned int ld_stlb_miss:1;
|
|
|
|
unsigned int ld_locked:1;
|
|
|
|
unsigned int ld_reserved:26;
|
|
|
|
};
|
|
|
|
struct {
|
|
|
|
unsigned int st_l1d_hit:1;
|
|
|
|
unsigned int st_reserved1:3;
|
|
|
|
unsigned int st_stlb_miss:1;
|
|
|
|
unsigned int st_locked:1;
|
|
|
|
unsigned int st_reserved2:26;
|
|
|
|
};
|
|
|
|
};
|
|
|
|
|
|
|
|
|
|
|
|
/*
|
|
|
|
* Map PEBS Load Latency Data Source encodings to generic
|
|
|
|
* memory data source information
|
|
|
|
*/
|
|
|
|
#define P(a, b) PERF_MEM_S(a, b)
|
|
|
|
#define OP_LH (P(OP, LOAD) | P(LVL, HIT))
|
|
|
|
#define SNOOP_NONE_MISS (P(SNOOP, NONE) | P(SNOOP, MISS))
|
|
|
|
|
|
|
|
static const u64 pebs_data_source[] = {
|
|
|
|
P(OP, LOAD) | P(LVL, MISS) | P(LVL, L3) | P(SNOOP, NA),/* 0x00:ukn L3 */
|
|
|
|
OP_LH | P(LVL, L1) | P(SNOOP, NONE), /* 0x01: L1 local */
|
|
|
|
OP_LH | P(LVL, LFB) | P(SNOOP, NONE), /* 0x02: LFB hit */
|
|
|
|
OP_LH | P(LVL, L2) | P(SNOOP, NONE), /* 0x03: L2 hit */
|
|
|
|
OP_LH | P(LVL, L3) | P(SNOOP, NONE), /* 0x04: L3 hit */
|
|
|
|
OP_LH | P(LVL, L3) | P(SNOOP, MISS), /* 0x05: L3 hit, snoop miss */
|
|
|
|
OP_LH | P(LVL, L3) | P(SNOOP, HIT), /* 0x06: L3 hit, snoop hit */
|
|
|
|
OP_LH | P(LVL, L3) | P(SNOOP, HITM), /* 0x07: L3 hit, snoop hitm */
|
|
|
|
OP_LH | P(LVL, REM_CCE1) | P(SNOOP, HIT), /* 0x08: L3 miss snoop hit */
|
|
|
|
OP_LH | P(LVL, REM_CCE1) | P(SNOOP, HITM), /* 0x09: L3 miss snoop hitm*/
|
|
|
|
OP_LH | P(LVL, LOC_RAM) | P(SNOOP, HIT), /* 0x0a: L3 miss, shared */
|
|
|
|
OP_LH | P(LVL, REM_RAM1) | P(SNOOP, HIT), /* 0x0b: L3 miss, shared */
|
|
|
|
OP_LH | P(LVL, LOC_RAM) | SNOOP_NONE_MISS,/* 0x0c: L3 miss, excl */
|
|
|
|
OP_LH | P(LVL, REM_RAM1) | SNOOP_NONE_MISS,/* 0x0d: L3 miss, excl */
|
|
|
|
OP_LH | P(LVL, IO) | P(SNOOP, NONE), /* 0x0e: I/O */
|
|
|
|
OP_LH | P(LVL, UNC) | P(SNOOP, NONE), /* 0x0f: uncached */
|
|
|
|
};
|
|
|
|
|
2013-01-24 15:10:34 +00:00
|
|
|
static u64 precise_store_data(u64 status)
|
|
|
|
{
|
|
|
|
union intel_x86_pebs_dse dse;
|
|
|
|
u64 val = P(OP, STORE) | P(SNOOP, NA) | P(LVL, L1) | P(TLB, L2);
|
|
|
|
|
|
|
|
dse.val = status;
|
|
|
|
|
|
|
|
/*
|
|
|
|
* bit 4: TLB access
|
|
|
|
* 1 = stored missed 2nd level TLB
|
|
|
|
*
|
|
|
|
* so it either hit the walker or the OS
|
|
|
|
* otherwise hit 2nd level TLB
|
|
|
|
*/
|
|
|
|
if (dse.st_stlb_miss)
|
|
|
|
val |= P(TLB, MISS);
|
|
|
|
else
|
|
|
|
val |= P(TLB, HIT);
|
|
|
|
|
|
|
|
/*
|
|
|
|
* bit 0: hit L1 data cache
|
|
|
|
* if not set, then all we know is that
|
|
|
|
* it missed L1D
|
|
|
|
*/
|
|
|
|
if (dse.st_l1d_hit)
|
|
|
|
val |= P(LVL, HIT);
|
|
|
|
else
|
|
|
|
val |= P(LVL, MISS);
|
|
|
|
|
|
|
|
/*
|
|
|
|
* bit 5: Locked prefix
|
|
|
|
*/
|
|
|
|
if (dse.st_locked)
|
|
|
|
val |= P(LOCK, LOCKED);
|
|
|
|
|
|
|
|
return val;
|
|
|
|
}
|
|
|
|
|
2014-08-11 19:27:13 +00:00
|
|
|
static u64 precise_datala_hsw(struct perf_event *event, u64 status)
|
2013-06-18 00:36:52 +00:00
|
|
|
{
|
|
|
|
union perf_mem_data_src dse;
|
|
|
|
|
2014-08-11 19:27:12 +00:00
|
|
|
dse.val = PERF_MEM_NA;
|
|
|
|
|
|
|
|
if (event->hw.flags & PERF_X86_EVENT_PEBS_ST_HSW)
|
|
|
|
dse.mem_op = PERF_MEM_OP_STORE;
|
|
|
|
else if (event->hw.flags & PERF_X86_EVENT_PEBS_LD_HSW)
|
|
|
|
dse.mem_op = PERF_MEM_OP_LOAD;
|
2014-05-15 15:56:44 +00:00
|
|
|
|
|
|
|
/*
|
|
|
|
* L1 info only valid for following events:
|
|
|
|
*
|
|
|
|
* MEM_UOPS_RETIRED.STLB_MISS_STORES
|
|
|
|
* MEM_UOPS_RETIRED.LOCK_STORES
|
|
|
|
* MEM_UOPS_RETIRED.SPLIT_STORES
|
|
|
|
* MEM_UOPS_RETIRED.ALL_STORES
|
|
|
|
*/
|
2014-08-11 19:27:13 +00:00
|
|
|
if (event->hw.flags & PERF_X86_EVENT_PEBS_ST_HSW) {
|
|
|
|
if (status & 1)
|
|
|
|
dse.mem_lvl = PERF_MEM_LVL_L1 | PERF_MEM_LVL_HIT;
|
|
|
|
else
|
|
|
|
dse.mem_lvl = PERF_MEM_LVL_L1 | PERF_MEM_LVL_MISS;
|
|
|
|
}
|
2013-06-18 00:36:52 +00:00
|
|
|
return dse.val;
|
|
|
|
}
|
|
|
|
|
2013-01-24 15:10:32 +00:00
|
|
|
static u64 load_latency_data(u64 status)
|
|
|
|
{
|
|
|
|
union intel_x86_pebs_dse dse;
|
|
|
|
u64 val;
|
|
|
|
int model = boot_cpu_data.x86_model;
|
|
|
|
int fam = boot_cpu_data.x86;
|
|
|
|
|
|
|
|
dse.val = status;
|
|
|
|
|
|
|
|
/*
|
|
|
|
* use the mapping table for bit 0-3
|
|
|
|
*/
|
|
|
|
val = pebs_data_source[dse.ld_dse];
|
|
|
|
|
|
|
|
/*
|
|
|
|
* Nehalem models do not support TLB, Lock infos
|
|
|
|
*/
|
|
|
|
if (fam == 0x6 && (model == 26 || model == 30
|
|
|
|
|| model == 31 || model == 46)) {
|
|
|
|
val |= P(TLB, NA) | P(LOCK, NA);
|
|
|
|
return val;
|
|
|
|
}
|
|
|
|
/*
|
|
|
|
* bit 4: TLB access
|
|
|
|
* 0 = did not miss 2nd level TLB
|
|
|
|
* 1 = missed 2nd level TLB
|
|
|
|
*/
|
|
|
|
if (dse.ld_stlb_miss)
|
|
|
|
val |= P(TLB, MISS) | P(TLB, L2);
|
|
|
|
else
|
|
|
|
val |= P(TLB, HIT) | P(TLB, L1) | P(TLB, L2);
|
|
|
|
|
|
|
|
/*
|
|
|
|
* bit 5: locked prefix
|
|
|
|
*/
|
|
|
|
if (dse.ld_locked)
|
|
|
|
val |= P(LOCK, LOCKED);
|
|
|
|
|
|
|
|
return val;
|
|
|
|
}
|
|
|
|
|
perf, x86: Add PEBS infrastructure
This patch implements support for Intel Precise Event Based Sampling,
which is an alternative counter mode in which the counter triggers a
hardware assist to collect information on events. The hardware assist
takes a trap like snapshot of a subset of the machine registers.
This data is written to the Intel Debug-Store, which can be programmed
with a data threshold at which to raise a PMI.
With the PEBS hardware assist being trap like, the reported IP is always
one instruction after the actual instruction that triggered the event.
This implements a simple PEBS model that always takes a single PEBS event
at a time. This is done so that the interaction with the rest of the
system is as expected (freq adjust, period randomization, lbr,
callchains, etc.).
It adds an ABI element: perf_event_attr::precise, which indicates that we
wish to use this (constrained, but precise) mode.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arnaldo Carvalho de Melo <acme@infradead.org>
Cc: paulus@samba.org
Cc: eranian@google.com
Cc: robert.richter@amd.com
Cc: fweisbec@gmail.com
LKML-Reference: <20100304140100.392111285@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-03-02 18:52:12 +00:00
|
|
|
struct pebs_record_core {
|
|
|
|
u64 flags, ip;
|
|
|
|
u64 ax, bx, cx, dx;
|
|
|
|
u64 si, di, bp, sp;
|
|
|
|
u64 r8, r9, r10, r11;
|
|
|
|
u64 r12, r13, r14, r15;
|
|
|
|
};
|
|
|
|
|
|
|
|
struct pebs_record_nhm {
|
|
|
|
u64 flags, ip;
|
|
|
|
u64 ax, bx, cx, dx;
|
|
|
|
u64 si, di, bp, sp;
|
|
|
|
u64 r8, r9, r10, r11;
|
|
|
|
u64 r12, r13, r14, r15;
|
|
|
|
u64 status, dla, dse, lat;
|
|
|
|
};
|
|
|
|
|
2013-06-18 00:36:47 +00:00
|
|
|
/*
|
|
|
|
* Same as pebs_record_nhm, with two additional fields.
|
|
|
|
*/
|
|
|
|
struct pebs_record_hsw {
|
2013-09-06 03:37:39 +00:00
|
|
|
u64 flags, ip;
|
|
|
|
u64 ax, bx, cx, dx;
|
|
|
|
u64 si, di, bp, sp;
|
|
|
|
u64 r8, r9, r10, r11;
|
|
|
|
u64 r12, r13, r14, r15;
|
|
|
|
u64 status, dla, dse, lat;
|
2013-09-12 11:00:47 +00:00
|
|
|
u64 real_ip, tsx_tuning;
|
2013-09-06 03:37:39 +00:00
|
|
|
};
|
|
|
|
|
|
|
|
union hsw_tsx_tuning {
|
|
|
|
struct {
|
|
|
|
u32 cycles_last_block : 32,
|
|
|
|
hle_abort : 1,
|
|
|
|
rtm_abort : 1,
|
|
|
|
instruction_abort : 1,
|
|
|
|
non_instruction_abort : 1,
|
|
|
|
retry : 1,
|
|
|
|
data_conflict : 1,
|
|
|
|
capacity_writes : 1,
|
|
|
|
capacity_reads : 1;
|
|
|
|
};
|
|
|
|
u64 value;
|
2013-06-18 00:36:47 +00:00
|
|
|
};
|
|
|
|
|
2013-09-20 14:40:40 +00:00
|
|
|
#define PEBS_HSW_TSX_FLAGS 0xff00000000ULL
|
|
|
|
|
2011-08-30 23:41:05 +00:00
|
|
|
void init_debug_store_on_cpu(int cpu)
|
perf, x86: Add PEBS infrastructure
This patch implements support for Intel Precise Event Based Sampling,
which is an alternative counter mode in which the counter triggers a
hardware assist to collect information on events. The hardware assist
takes a trap like snapshot of a subset of the machine registers.
This data is written to the Intel Debug-Store, which can be programmed
with a data threshold at which to raise a PMI.
With the PEBS hardware assist being trap like, the reported IP is always
one instruction after the actual instruction that triggered the event.
This implements a simple PEBS model that always takes a single PEBS event
at a time. This is done so that the interaction with the rest of the
system is as expected (freq adjust, period randomization, lbr,
callchains, etc.).
It adds an ABI element: perf_event_attr::precise, which indicates that we
wish to use this (constrained, but precise) mode.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arnaldo Carvalho de Melo <acme@infradead.org>
Cc: paulus@samba.org
Cc: eranian@google.com
Cc: robert.richter@amd.com
Cc: fweisbec@gmail.com
LKML-Reference: <20100304140100.392111285@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-03-02 18:52:12 +00:00
|
|
|
{
|
|
|
|
struct debug_store *ds = per_cpu(cpu_hw_events, cpu).ds;
|
|
|
|
|
|
|
|
if (!ds)
|
|
|
|
return;
|
|
|
|
|
|
|
|
wrmsr_on_cpu(cpu, MSR_IA32_DS_AREA,
|
|
|
|
(u32)((u64)(unsigned long)ds),
|
|
|
|
(u32)((u64)(unsigned long)ds >> 32));
|
|
|
|
}
|
|
|
|
|
2011-08-30 23:41:05 +00:00
|
|
|
void fini_debug_store_on_cpu(int cpu)
|
perf, x86: Add PEBS infrastructure
This patch implements support for Intel Precise Event Based Sampling,
which is an alternative counter mode in which the counter triggers a
hardware assist to collect information on events. The hardware assist
takes a trap like snapshot of a subset of the machine registers.
This data is written to the Intel Debug-Store, which can be programmed
with a data threshold at which to raise a PMI.
With the PEBS hardware assist being trap like, the reported IP is always
one instruction after the actual instruction that triggered the event.
This implements a simple PEBS model that always takes a single PEBS event
at a time. This is done so that the interaction with the rest of the
system is as expected (freq adjust, period randomization, lbr,
callchains, etc.).
It adds an ABI element: perf_event_attr::precise, which indicates that we
wish to use this (constrained, but precise) mode.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arnaldo Carvalho de Melo <acme@infradead.org>
Cc: paulus@samba.org
Cc: eranian@google.com
Cc: robert.richter@amd.com
Cc: fweisbec@gmail.com
LKML-Reference: <20100304140100.392111285@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-03-02 18:52:12 +00:00
|
|
|
{
|
|
|
|
if (!per_cpu(cpu_hw_events, cpu).ds)
|
|
|
|
return;
|
|
|
|
|
|
|
|
wrmsr_on_cpu(cpu, MSR_IA32_DS_AREA, 0, 0);
|
|
|
|
}
|
|
|
|
|
perf/x86: Optimize intel_pmu_pebs_fixup_ip()
There's been reports of high NMI handler overhead, highlighted by
such kernel messages:
[ 3697.380195] perf samples too long (10009 > 10000), lowering kernel.perf_event_max_sample_rate to 13000
[ 3697.389509] INFO: NMI handler (perf_event_nmi_handler) took too long to run: 9.331 msecs
Don Zickus analyzed the source of the overhead and reported:
> While there are a few places that are causing latencies, for now I focused on
> the longest one first. It seems to be 'copy_user_from_nmi'
>
> intel_pmu_handle_irq ->
> intel_pmu_drain_pebs_nhm ->
> __intel_pmu_drain_pebs_nhm ->
> __intel_pmu_pebs_event ->
> intel_pmu_pebs_fixup_ip ->
> copy_from_user_nmi
>
> In intel_pmu_pebs_fixup_ip(), if the while-loop goes over 50, the sum of
> all the copy_from_user_nmi latencies seems to go over 1,000,000 cycles
> (there are some cases where only 10 iterations are needed to go that high
> too, but in generall over 50 or so). At this point copy_user_from_nmi
> seems to account for over 90% of the nmi latency.
The solution to that is to avoid having to call copy_from_user_nmi() for
every instruction.
Since we already limit the max basic block size, we can easily
pre-allocate a piece of memory to copy the entire thing into in one
go.
Don reported this test result:
> Your patch made a huge difference in improvement. The
> copy_from_user_nmi() no longer hits the million of cycles. I still
> have a batch of 100,000-300,000 cycles. My longest NMI paths used
> to be dominated by copy_from_user_nmi, now it is not (I have to dig
> up the new hot path).
Reported-and-tested-by: Don Zickus <dzickus@redhat.com>
Cc: jmario@redhat.com
Cc: acme@infradead.org
Cc: dave.hansen@linux.intel.com
Cc: eranian@google.com
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20131016105755.GX10651@twins.programming.kicks-ass.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-10-15 10:14:04 +00:00
|
|
|
static DEFINE_PER_CPU(void *, insn_buffer);
|
|
|
|
|
2010-10-19 12:15:04 +00:00
|
|
|
static int alloc_pebs_buffer(int cpu)
|
|
|
|
{
|
|
|
|
struct debug_store *ds = per_cpu(cpu_hw_events, cpu).ds;
|
2010-10-19 12:55:33 +00:00
|
|
|
int node = cpu_to_node(cpu);
|
2010-10-19 12:15:04 +00:00
|
|
|
int max, thresh = 1; /* always use a single PEBS record */
|
perf/x86: Optimize intel_pmu_pebs_fixup_ip()
There's been reports of high NMI handler overhead, highlighted by
such kernel messages:
[ 3697.380195] perf samples too long (10009 > 10000), lowering kernel.perf_event_max_sample_rate to 13000
[ 3697.389509] INFO: NMI handler (perf_event_nmi_handler) took too long to run: 9.331 msecs
Don Zickus analyzed the source of the overhead and reported:
> While there are a few places that are causing latencies, for now I focused on
> the longest one first. It seems to be 'copy_user_from_nmi'
>
> intel_pmu_handle_irq ->
> intel_pmu_drain_pebs_nhm ->
> __intel_pmu_drain_pebs_nhm ->
> __intel_pmu_pebs_event ->
> intel_pmu_pebs_fixup_ip ->
> copy_from_user_nmi
>
> In intel_pmu_pebs_fixup_ip(), if the while-loop goes over 50, the sum of
> all the copy_from_user_nmi latencies seems to go over 1,000,000 cycles
> (there are some cases where only 10 iterations are needed to go that high
> too, but in generall over 50 or so). At this point copy_user_from_nmi
> seems to account for over 90% of the nmi latency.
The solution to that is to avoid having to call copy_from_user_nmi() for
every instruction.
Since we already limit the max basic block size, we can easily
pre-allocate a piece of memory to copy the entire thing into in one
go.
Don reported this test result:
> Your patch made a huge difference in improvement. The
> copy_from_user_nmi() no longer hits the million of cycles. I still
> have a batch of 100,000-300,000 cycles. My longest NMI paths used
> to be dominated by copy_from_user_nmi, now it is not (I have to dig
> up the new hot path).
Reported-and-tested-by: Don Zickus <dzickus@redhat.com>
Cc: jmario@redhat.com
Cc: acme@infradead.org
Cc: dave.hansen@linux.intel.com
Cc: eranian@google.com
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20131016105755.GX10651@twins.programming.kicks-ass.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-10-15 10:14:04 +00:00
|
|
|
void *buffer, *ibuffer;
|
2010-10-19 12:15:04 +00:00
|
|
|
|
|
|
|
if (!x86_pmu.pebs)
|
|
|
|
return 0;
|
|
|
|
|
2013-08-29 20:59:17 +00:00
|
|
|
buffer = kzalloc_node(PEBS_BUFFER_SIZE, GFP_KERNEL, node);
|
2010-10-19 12:15:04 +00:00
|
|
|
if (unlikely(!buffer))
|
|
|
|
return -ENOMEM;
|
|
|
|
|
perf/x86: Optimize intel_pmu_pebs_fixup_ip()
There's been reports of high NMI handler overhead, highlighted by
such kernel messages:
[ 3697.380195] perf samples too long (10009 > 10000), lowering kernel.perf_event_max_sample_rate to 13000
[ 3697.389509] INFO: NMI handler (perf_event_nmi_handler) took too long to run: 9.331 msecs
Don Zickus analyzed the source of the overhead and reported:
> While there are a few places that are causing latencies, for now I focused on
> the longest one first. It seems to be 'copy_user_from_nmi'
>
> intel_pmu_handle_irq ->
> intel_pmu_drain_pebs_nhm ->
> __intel_pmu_drain_pebs_nhm ->
> __intel_pmu_pebs_event ->
> intel_pmu_pebs_fixup_ip ->
> copy_from_user_nmi
>
> In intel_pmu_pebs_fixup_ip(), if the while-loop goes over 50, the sum of
> all the copy_from_user_nmi latencies seems to go over 1,000,000 cycles
> (there are some cases where only 10 iterations are needed to go that high
> too, but in generall over 50 or so). At this point copy_user_from_nmi
> seems to account for over 90% of the nmi latency.
The solution to that is to avoid having to call copy_from_user_nmi() for
every instruction.
Since we already limit the max basic block size, we can easily
pre-allocate a piece of memory to copy the entire thing into in one
go.
Don reported this test result:
> Your patch made a huge difference in improvement. The
> copy_from_user_nmi() no longer hits the million of cycles. I still
> have a batch of 100,000-300,000 cycles. My longest NMI paths used
> to be dominated by copy_from_user_nmi, now it is not (I have to dig
> up the new hot path).
Reported-and-tested-by: Don Zickus <dzickus@redhat.com>
Cc: jmario@redhat.com
Cc: acme@infradead.org
Cc: dave.hansen@linux.intel.com
Cc: eranian@google.com
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20131016105755.GX10651@twins.programming.kicks-ass.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-10-15 10:14:04 +00:00
|
|
|
/*
|
|
|
|
* HSW+ already provides us the eventing ip; no need to allocate this
|
|
|
|
* buffer then.
|
|
|
|
*/
|
|
|
|
if (x86_pmu.intel_cap.pebs_format < 2) {
|
|
|
|
ibuffer = kzalloc_node(PEBS_FIXUP_SIZE, GFP_KERNEL, node);
|
|
|
|
if (!ibuffer) {
|
|
|
|
kfree(buffer);
|
|
|
|
return -ENOMEM;
|
|
|
|
}
|
|
|
|
per_cpu(insn_buffer, cpu) = ibuffer;
|
|
|
|
}
|
|
|
|
|
2010-10-19 12:15:04 +00:00
|
|
|
max = PEBS_BUFFER_SIZE / x86_pmu.pebs_record_size;
|
|
|
|
|
|
|
|
ds->pebs_buffer_base = (u64)(unsigned long)buffer;
|
|
|
|
ds->pebs_index = ds->pebs_buffer_base;
|
|
|
|
ds->pebs_absolute_maximum = ds->pebs_buffer_base +
|
|
|
|
max * x86_pmu.pebs_record_size;
|
|
|
|
|
|
|
|
ds->pebs_interrupt_threshold = ds->pebs_buffer_base +
|
|
|
|
thresh * x86_pmu.pebs_record_size;
|
|
|
|
|
|
|
|
return 0;
|
|
|
|
}
|
|
|
|
|
2010-10-19 12:08:29 +00:00
|
|
|
static void release_pebs_buffer(int cpu)
|
|
|
|
{
|
|
|
|
struct debug_store *ds = per_cpu(cpu_hw_events, cpu).ds;
|
|
|
|
|
|
|
|
if (!ds || !x86_pmu.pebs)
|
|
|
|
return;
|
|
|
|
|
perf/x86: Optimize intel_pmu_pebs_fixup_ip()
There's been reports of high NMI handler overhead, highlighted by
such kernel messages:
[ 3697.380195] perf samples too long (10009 > 10000), lowering kernel.perf_event_max_sample_rate to 13000
[ 3697.389509] INFO: NMI handler (perf_event_nmi_handler) took too long to run: 9.331 msecs
Don Zickus analyzed the source of the overhead and reported:
> While there are a few places that are causing latencies, for now I focused on
> the longest one first. It seems to be 'copy_user_from_nmi'
>
> intel_pmu_handle_irq ->
> intel_pmu_drain_pebs_nhm ->
> __intel_pmu_drain_pebs_nhm ->
> __intel_pmu_pebs_event ->
> intel_pmu_pebs_fixup_ip ->
> copy_from_user_nmi
>
> In intel_pmu_pebs_fixup_ip(), if the while-loop goes over 50, the sum of
> all the copy_from_user_nmi latencies seems to go over 1,000,000 cycles
> (there are some cases where only 10 iterations are needed to go that high
> too, but in generall over 50 or so). At this point copy_user_from_nmi
> seems to account for over 90% of the nmi latency.
The solution to that is to avoid having to call copy_from_user_nmi() for
every instruction.
Since we already limit the max basic block size, we can easily
pre-allocate a piece of memory to copy the entire thing into in one
go.
Don reported this test result:
> Your patch made a huge difference in improvement. The
> copy_from_user_nmi() no longer hits the million of cycles. I still
> have a batch of 100,000-300,000 cycles. My longest NMI paths used
> to be dominated by copy_from_user_nmi, now it is not (I have to dig
> up the new hot path).
Reported-and-tested-by: Don Zickus <dzickus@redhat.com>
Cc: jmario@redhat.com
Cc: acme@infradead.org
Cc: dave.hansen@linux.intel.com
Cc: eranian@google.com
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20131016105755.GX10651@twins.programming.kicks-ass.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-10-15 10:14:04 +00:00
|
|
|
kfree(per_cpu(insn_buffer, cpu));
|
|
|
|
per_cpu(insn_buffer, cpu) = NULL;
|
|
|
|
|
2010-10-19 12:08:29 +00:00
|
|
|
kfree((void *)(unsigned long)ds->pebs_buffer_base);
|
|
|
|
ds->pebs_buffer_base = 0;
|
|
|
|
}
|
|
|
|
|
2010-10-19 12:15:04 +00:00
|
|
|
static int alloc_bts_buffer(int cpu)
|
|
|
|
{
|
|
|
|
struct debug_store *ds = per_cpu(cpu_hw_events, cpu).ds;
|
2010-10-19 12:55:33 +00:00
|
|
|
int node = cpu_to_node(cpu);
|
2010-10-19 12:15:04 +00:00
|
|
|
int max, thresh;
|
|
|
|
void *buffer;
|
|
|
|
|
|
|
|
if (!x86_pmu.bts)
|
|
|
|
return 0;
|
|
|
|
|
2014-06-30 23:04:08 +00:00
|
|
|
buffer = kzalloc_node(BTS_BUFFER_SIZE, GFP_KERNEL | __GFP_NOWARN, node);
|
|
|
|
if (unlikely(!buffer)) {
|
|
|
|
WARN_ONCE(1, "%s: BTS buffer allocation failure\n", __func__);
|
2010-10-19 12:15:04 +00:00
|
|
|
return -ENOMEM;
|
2014-06-30 23:04:08 +00:00
|
|
|
}
|
2010-10-19 12:15:04 +00:00
|
|
|
|
|
|
|
max = BTS_BUFFER_SIZE / BTS_RECORD_SIZE;
|
|
|
|
thresh = max / 16;
|
|
|
|
|
|
|
|
ds->bts_buffer_base = (u64)(unsigned long)buffer;
|
|
|
|
ds->bts_index = ds->bts_buffer_base;
|
|
|
|
ds->bts_absolute_maximum = ds->bts_buffer_base +
|
|
|
|
max * BTS_RECORD_SIZE;
|
|
|
|
ds->bts_interrupt_threshold = ds->bts_absolute_maximum -
|
|
|
|
thresh * BTS_RECORD_SIZE;
|
|
|
|
|
|
|
|
return 0;
|
|
|
|
}
|
|
|
|
|
2010-10-19 12:08:29 +00:00
|
|
|
static void release_bts_buffer(int cpu)
|
|
|
|
{
|
|
|
|
struct debug_store *ds = per_cpu(cpu_hw_events, cpu).ds;
|
|
|
|
|
|
|
|
if (!ds || !x86_pmu.bts)
|
|
|
|
return;
|
|
|
|
|
|
|
|
kfree((void *)(unsigned long)ds->bts_buffer_base);
|
|
|
|
ds->bts_buffer_base = 0;
|
|
|
|
}
|
|
|
|
|
2010-10-19 12:37:23 +00:00
|
|
|
static int alloc_ds_buffer(int cpu)
|
|
|
|
{
|
2010-10-19 12:55:33 +00:00
|
|
|
int node = cpu_to_node(cpu);
|
2010-10-19 12:37:23 +00:00
|
|
|
struct debug_store *ds;
|
|
|
|
|
2013-08-29 20:59:17 +00:00
|
|
|
ds = kzalloc_node(sizeof(*ds), GFP_KERNEL, node);
|
2010-10-19 12:37:23 +00:00
|
|
|
if (unlikely(!ds))
|
|
|
|
return -ENOMEM;
|
|
|
|
|
|
|
|
per_cpu(cpu_hw_events, cpu).ds = ds;
|
|
|
|
|
|
|
|
return 0;
|
|
|
|
}
|
|
|
|
|
|
|
|
static void release_ds_buffer(int cpu)
|
|
|
|
{
|
|
|
|
struct debug_store *ds = per_cpu(cpu_hw_events, cpu).ds;
|
|
|
|
|
|
|
|
if (!ds)
|
|
|
|
return;
|
|
|
|
|
|
|
|
per_cpu(cpu_hw_events, cpu).ds = NULL;
|
|
|
|
kfree(ds);
|
|
|
|
}
|
|
|
|
|
2011-08-30 23:41:05 +00:00
|
|
|
void release_ds_buffers(void)
|
perf, x86: Add PEBS infrastructure
This patch implements support for Intel Precise Event Based Sampling,
which is an alternative counter mode in which the counter triggers a
hardware assist to collect information on events. The hardware assist
takes a trap like snapshot of a subset of the machine registers.
This data is written to the Intel Debug-Store, which can be programmed
with a data threshold at which to raise a PMI.
With the PEBS hardware assist being trap like, the reported IP is always
one instruction after the actual instruction that triggered the event.
This implements a simple PEBS model that always takes a single PEBS event
at a time. This is done so that the interaction with the rest of the
system is as expected (freq adjust, period randomization, lbr,
callchains, etc.).
It adds an ABI element: perf_event_attr::precise, which indicates that we
wish to use this (constrained, but precise) mode.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arnaldo Carvalho de Melo <acme@infradead.org>
Cc: paulus@samba.org
Cc: eranian@google.com
Cc: robert.richter@amd.com
Cc: fweisbec@gmail.com
LKML-Reference: <20100304140100.392111285@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-03-02 18:52:12 +00:00
|
|
|
{
|
|
|
|
int cpu;
|
|
|
|
|
|
|
|
if (!x86_pmu.bts && !x86_pmu.pebs)
|
|
|
|
return;
|
|
|
|
|
|
|
|
get_online_cpus();
|
|
|
|
for_each_online_cpu(cpu)
|
|
|
|
fini_debug_store_on_cpu(cpu);
|
|
|
|
|
|
|
|
for_each_possible_cpu(cpu) {
|
2010-10-19 12:08:29 +00:00
|
|
|
release_pebs_buffer(cpu);
|
|
|
|
release_bts_buffer(cpu);
|
2010-10-19 12:37:23 +00:00
|
|
|
release_ds_buffer(cpu);
|
perf, x86: Add PEBS infrastructure
This patch implements support for Intel Precise Event Based Sampling,
which is an alternative counter mode in which the counter triggers a
hardware assist to collect information on events. The hardware assist
takes a trap like snapshot of a subset of the machine registers.
This data is written to the Intel Debug-Store, which can be programmed
with a data threshold at which to raise a PMI.
With the PEBS hardware assist being trap like, the reported IP is always
one instruction after the actual instruction that triggered the event.
This implements a simple PEBS model that always takes a single PEBS event
at a time. This is done so that the interaction with the rest of the
system is as expected (freq adjust, period randomization, lbr,
callchains, etc.).
It adds an ABI element: perf_event_attr::precise, which indicates that we
wish to use this (constrained, but precise) mode.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arnaldo Carvalho de Melo <acme@infradead.org>
Cc: paulus@samba.org
Cc: eranian@google.com
Cc: robert.richter@amd.com
Cc: fweisbec@gmail.com
LKML-Reference: <20100304140100.392111285@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-03-02 18:52:12 +00:00
|
|
|
}
|
|
|
|
put_online_cpus();
|
|
|
|
}
|
|
|
|
|
2011-08-30 23:41:05 +00:00
|
|
|
void reserve_ds_buffers(void)
|
perf, x86: Add PEBS infrastructure
This patch implements support for Intel Precise Event Based Sampling,
which is an alternative counter mode in which the counter triggers a
hardware assist to collect information on events. The hardware assist
takes a trap like snapshot of a subset of the machine registers.
This data is written to the Intel Debug-Store, which can be programmed
with a data threshold at which to raise a PMI.
With the PEBS hardware assist being trap like, the reported IP is always
one instruction after the actual instruction that triggered the event.
This implements a simple PEBS model that always takes a single PEBS event
at a time. This is done so that the interaction with the rest of the
system is as expected (freq adjust, period randomization, lbr,
callchains, etc.).
It adds an ABI element: perf_event_attr::precise, which indicates that we
wish to use this (constrained, but precise) mode.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arnaldo Carvalho de Melo <acme@infradead.org>
Cc: paulus@samba.org
Cc: eranian@google.com
Cc: robert.richter@amd.com
Cc: fweisbec@gmail.com
LKML-Reference: <20100304140100.392111285@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-03-02 18:52:12 +00:00
|
|
|
{
|
2010-10-19 12:22:50 +00:00
|
|
|
int bts_err = 0, pebs_err = 0;
|
|
|
|
int cpu;
|
|
|
|
|
|
|
|
x86_pmu.bts_active = 0;
|
|
|
|
x86_pmu.pebs_active = 0;
|
perf, x86: Add PEBS infrastructure
This patch implements support for Intel Precise Event Based Sampling,
which is an alternative counter mode in which the counter triggers a
hardware assist to collect information on events. The hardware assist
takes a trap like snapshot of a subset of the machine registers.
This data is written to the Intel Debug-Store, which can be programmed
with a data threshold at which to raise a PMI.
With the PEBS hardware assist being trap like, the reported IP is always
one instruction after the actual instruction that triggered the event.
This implements a simple PEBS model that always takes a single PEBS event
at a time. This is done so that the interaction with the rest of the
system is as expected (freq adjust, period randomization, lbr,
callchains, etc.).
It adds an ABI element: perf_event_attr::precise, which indicates that we
wish to use this (constrained, but precise) mode.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arnaldo Carvalho de Melo <acme@infradead.org>
Cc: paulus@samba.org
Cc: eranian@google.com
Cc: robert.richter@amd.com
Cc: fweisbec@gmail.com
LKML-Reference: <20100304140100.392111285@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-03-02 18:52:12 +00:00
|
|
|
|
|
|
|
if (!x86_pmu.bts && !x86_pmu.pebs)
|
2010-10-19 12:50:02 +00:00
|
|
|
return;
|
perf, x86: Add PEBS infrastructure
This patch implements support for Intel Precise Event Based Sampling,
which is an alternative counter mode in which the counter triggers a
hardware assist to collect information on events. The hardware assist
takes a trap like snapshot of a subset of the machine registers.
This data is written to the Intel Debug-Store, which can be programmed
with a data threshold at which to raise a PMI.
With the PEBS hardware assist being trap like, the reported IP is always
one instruction after the actual instruction that triggered the event.
This implements a simple PEBS model that always takes a single PEBS event
at a time. This is done so that the interaction with the rest of the
system is as expected (freq adjust, period randomization, lbr,
callchains, etc.).
It adds an ABI element: perf_event_attr::precise, which indicates that we
wish to use this (constrained, but precise) mode.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arnaldo Carvalho de Melo <acme@infradead.org>
Cc: paulus@samba.org
Cc: eranian@google.com
Cc: robert.richter@amd.com
Cc: fweisbec@gmail.com
LKML-Reference: <20100304140100.392111285@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-03-02 18:52:12 +00:00
|
|
|
|
2010-10-19 12:22:50 +00:00
|
|
|
if (!x86_pmu.bts)
|
|
|
|
bts_err = 1;
|
|
|
|
|
|
|
|
if (!x86_pmu.pebs)
|
|
|
|
pebs_err = 1;
|
|
|
|
|
perf, x86: Add PEBS infrastructure
This patch implements support for Intel Precise Event Based Sampling,
which is an alternative counter mode in which the counter triggers a
hardware assist to collect information on events. The hardware assist
takes a trap like snapshot of a subset of the machine registers.
This data is written to the Intel Debug-Store, which can be programmed
with a data threshold at which to raise a PMI.
With the PEBS hardware assist being trap like, the reported IP is always
one instruction after the actual instruction that triggered the event.
This implements a simple PEBS model that always takes a single PEBS event
at a time. This is done so that the interaction with the rest of the
system is as expected (freq adjust, period randomization, lbr,
callchains, etc.).
It adds an ABI element: perf_event_attr::precise, which indicates that we
wish to use this (constrained, but precise) mode.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arnaldo Carvalho de Melo <acme@infradead.org>
Cc: paulus@samba.org
Cc: eranian@google.com
Cc: robert.richter@amd.com
Cc: fweisbec@gmail.com
LKML-Reference: <20100304140100.392111285@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-03-02 18:52:12 +00:00
|
|
|
get_online_cpus();
|
|
|
|
|
|
|
|
for_each_possible_cpu(cpu) {
|
2010-10-19 12:22:50 +00:00
|
|
|
if (alloc_ds_buffer(cpu)) {
|
|
|
|
bts_err = 1;
|
|
|
|
pebs_err = 1;
|
|
|
|
}
|
perf, x86: Add PEBS infrastructure
This patch implements support for Intel Precise Event Based Sampling,
which is an alternative counter mode in which the counter triggers a
hardware assist to collect information on events. The hardware assist
takes a trap like snapshot of a subset of the machine registers.
This data is written to the Intel Debug-Store, which can be programmed
with a data threshold at which to raise a PMI.
With the PEBS hardware assist being trap like, the reported IP is always
one instruction after the actual instruction that triggered the event.
This implements a simple PEBS model that always takes a single PEBS event
at a time. This is done so that the interaction with the rest of the
system is as expected (freq adjust, period randomization, lbr,
callchains, etc.).
It adds an ABI element: perf_event_attr::precise, which indicates that we
wish to use this (constrained, but precise) mode.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arnaldo Carvalho de Melo <acme@infradead.org>
Cc: paulus@samba.org
Cc: eranian@google.com
Cc: robert.richter@amd.com
Cc: fweisbec@gmail.com
LKML-Reference: <20100304140100.392111285@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-03-02 18:52:12 +00:00
|
|
|
|
2010-10-19 12:22:50 +00:00
|
|
|
if (!bts_err && alloc_bts_buffer(cpu))
|
|
|
|
bts_err = 1;
|
|
|
|
|
|
|
|
if (!pebs_err && alloc_pebs_buffer(cpu))
|
|
|
|
pebs_err = 1;
|
2010-10-19 12:15:04 +00:00
|
|
|
|
2010-10-19 12:22:50 +00:00
|
|
|
if (bts_err && pebs_err)
|
2010-10-19 12:15:04 +00:00
|
|
|
break;
|
2010-10-19 12:22:50 +00:00
|
|
|
}
|
|
|
|
|
|
|
|
if (bts_err) {
|
|
|
|
for_each_possible_cpu(cpu)
|
|
|
|
release_bts_buffer(cpu);
|
|
|
|
}
|
perf, x86: Add PEBS infrastructure
This patch implements support for Intel Precise Event Based Sampling,
which is an alternative counter mode in which the counter triggers a
hardware assist to collect information on events. The hardware assist
takes a trap like snapshot of a subset of the machine registers.
This data is written to the Intel Debug-Store, which can be programmed
with a data threshold at which to raise a PMI.
With the PEBS hardware assist being trap like, the reported IP is always
one instruction after the actual instruction that triggered the event.
This implements a simple PEBS model that always takes a single PEBS event
at a time. This is done so that the interaction with the rest of the
system is as expected (freq adjust, period randomization, lbr,
callchains, etc.).
It adds an ABI element: perf_event_attr::precise, which indicates that we
wish to use this (constrained, but precise) mode.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arnaldo Carvalho de Melo <acme@infradead.org>
Cc: paulus@samba.org
Cc: eranian@google.com
Cc: robert.richter@amd.com
Cc: fweisbec@gmail.com
LKML-Reference: <20100304140100.392111285@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-03-02 18:52:12 +00:00
|
|
|
|
2010-10-19 12:22:50 +00:00
|
|
|
if (pebs_err) {
|
|
|
|
for_each_possible_cpu(cpu)
|
|
|
|
release_pebs_buffer(cpu);
|
perf, x86: Add PEBS infrastructure
This patch implements support for Intel Precise Event Based Sampling,
which is an alternative counter mode in which the counter triggers a
hardware assist to collect information on events. The hardware assist
takes a trap like snapshot of a subset of the machine registers.
This data is written to the Intel Debug-Store, which can be programmed
with a data threshold at which to raise a PMI.
With the PEBS hardware assist being trap like, the reported IP is always
one instruction after the actual instruction that triggered the event.
This implements a simple PEBS model that always takes a single PEBS event
at a time. This is done so that the interaction with the rest of the
system is as expected (freq adjust, period randomization, lbr,
callchains, etc.).
It adds an ABI element: perf_event_attr::precise, which indicates that we
wish to use this (constrained, but precise) mode.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arnaldo Carvalho de Melo <acme@infradead.org>
Cc: paulus@samba.org
Cc: eranian@google.com
Cc: robert.richter@amd.com
Cc: fweisbec@gmail.com
LKML-Reference: <20100304140100.392111285@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-03-02 18:52:12 +00:00
|
|
|
}
|
|
|
|
|
2010-10-19 12:22:50 +00:00
|
|
|
if (bts_err && pebs_err) {
|
|
|
|
for_each_possible_cpu(cpu)
|
|
|
|
release_ds_buffer(cpu);
|
|
|
|
} else {
|
|
|
|
if (x86_pmu.bts && !bts_err)
|
|
|
|
x86_pmu.bts_active = 1;
|
|
|
|
|
|
|
|
if (x86_pmu.pebs && !pebs_err)
|
|
|
|
x86_pmu.pebs_active = 1;
|
|
|
|
|
perf, x86: Add PEBS infrastructure
This patch implements support for Intel Precise Event Based Sampling,
which is an alternative counter mode in which the counter triggers a
hardware assist to collect information on events. The hardware assist
takes a trap like snapshot of a subset of the machine registers.
This data is written to the Intel Debug-Store, which can be programmed
with a data threshold at which to raise a PMI.
With the PEBS hardware assist being trap like, the reported IP is always
one instruction after the actual instruction that triggered the event.
This implements a simple PEBS model that always takes a single PEBS event
at a time. This is done so that the interaction with the rest of the
system is as expected (freq adjust, period randomization, lbr,
callchains, etc.).
It adds an ABI element: perf_event_attr::precise, which indicates that we
wish to use this (constrained, but precise) mode.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arnaldo Carvalho de Melo <acme@infradead.org>
Cc: paulus@samba.org
Cc: eranian@google.com
Cc: robert.richter@amd.com
Cc: fweisbec@gmail.com
LKML-Reference: <20100304140100.392111285@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-03-02 18:52:12 +00:00
|
|
|
for_each_online_cpu(cpu)
|
|
|
|
init_debug_store_on_cpu(cpu);
|
|
|
|
}
|
|
|
|
|
|
|
|
put_online_cpus();
|
|
|
|
}
|
|
|
|
|
|
|
|
/*
|
|
|
|
* BTS
|
|
|
|
*/
|
|
|
|
|
2011-08-30 23:41:05 +00:00
|
|
|
struct event_constraint bts_constraint =
|
2012-06-20 18:46:33 +00:00
|
|
|
EVENT_CONSTRAINT(0, 1ULL << INTEL_PMC_IDX_FIXED_BTS, 0);
|
perf, x86: Add PEBS infrastructure
This patch implements support for Intel Precise Event Based Sampling,
which is an alternative counter mode in which the counter triggers a
hardware assist to collect information on events. The hardware assist
takes a trap like snapshot of a subset of the machine registers.
This data is written to the Intel Debug-Store, which can be programmed
with a data threshold at which to raise a PMI.
With the PEBS hardware assist being trap like, the reported IP is always
one instruction after the actual instruction that triggered the event.
This implements a simple PEBS model that always takes a single PEBS event
at a time. This is done so that the interaction with the rest of the
system is as expected (freq adjust, period randomization, lbr,
callchains, etc.).
It adds an ABI element: perf_event_attr::precise, which indicates that we
wish to use this (constrained, but precise) mode.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arnaldo Carvalho de Melo <acme@infradead.org>
Cc: paulus@samba.org
Cc: eranian@google.com
Cc: robert.richter@amd.com
Cc: fweisbec@gmail.com
LKML-Reference: <20100304140100.392111285@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-03-02 18:52:12 +00:00
|
|
|
|
2011-08-30 23:41:05 +00:00
|
|
|
void intel_pmu_enable_bts(u64 config)
|
perf, x86: Add PEBS infrastructure
This patch implements support for Intel Precise Event Based Sampling,
which is an alternative counter mode in which the counter triggers a
hardware assist to collect information on events. The hardware assist
takes a trap like snapshot of a subset of the machine registers.
This data is written to the Intel Debug-Store, which can be programmed
with a data threshold at which to raise a PMI.
With the PEBS hardware assist being trap like, the reported IP is always
one instruction after the actual instruction that triggered the event.
This implements a simple PEBS model that always takes a single PEBS event
at a time. This is done so that the interaction with the rest of the
system is as expected (freq adjust, period randomization, lbr,
callchains, etc.).
It adds an ABI element: perf_event_attr::precise, which indicates that we
wish to use this (constrained, but precise) mode.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arnaldo Carvalho de Melo <acme@infradead.org>
Cc: paulus@samba.org
Cc: eranian@google.com
Cc: robert.richter@amd.com
Cc: fweisbec@gmail.com
LKML-Reference: <20100304140100.392111285@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-03-02 18:52:12 +00:00
|
|
|
{
|
|
|
|
unsigned long debugctlmsr;
|
|
|
|
|
|
|
|
debugctlmsr = get_debugctlmsr();
|
|
|
|
|
2010-03-25 13:51:49 +00:00
|
|
|
debugctlmsr |= DEBUGCTLMSR_TR;
|
|
|
|
debugctlmsr |= DEBUGCTLMSR_BTS;
|
|
|
|
debugctlmsr |= DEBUGCTLMSR_BTINT;
|
perf, x86: Add PEBS infrastructure
This patch implements support for Intel Precise Event Based Sampling,
which is an alternative counter mode in which the counter triggers a
hardware assist to collect information on events. The hardware assist
takes a trap like snapshot of a subset of the machine registers.
This data is written to the Intel Debug-Store, which can be programmed
with a data threshold at which to raise a PMI.
With the PEBS hardware assist being trap like, the reported IP is always
one instruction after the actual instruction that triggered the event.
This implements a simple PEBS model that always takes a single PEBS event
at a time. This is done so that the interaction with the rest of the
system is as expected (freq adjust, period randomization, lbr,
callchains, etc.).
It adds an ABI element: perf_event_attr::precise, which indicates that we
wish to use this (constrained, but precise) mode.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arnaldo Carvalho de Melo <acme@infradead.org>
Cc: paulus@samba.org
Cc: eranian@google.com
Cc: robert.richter@amd.com
Cc: fweisbec@gmail.com
LKML-Reference: <20100304140100.392111285@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-03-02 18:52:12 +00:00
|
|
|
|
|
|
|
if (!(config & ARCH_PERFMON_EVENTSEL_OS))
|
2010-03-25 13:51:49 +00:00
|
|
|
debugctlmsr |= DEBUGCTLMSR_BTS_OFF_OS;
|
perf, x86: Add PEBS infrastructure
This patch implements support for Intel Precise Event Based Sampling,
which is an alternative counter mode in which the counter triggers a
hardware assist to collect information on events. The hardware assist
takes a trap like snapshot of a subset of the machine registers.
This data is written to the Intel Debug-Store, which can be programmed
with a data threshold at which to raise a PMI.
With the PEBS hardware assist being trap like, the reported IP is always
one instruction after the actual instruction that triggered the event.
This implements a simple PEBS model that always takes a single PEBS event
at a time. This is done so that the interaction with the rest of the
system is as expected (freq adjust, period randomization, lbr,
callchains, etc.).
It adds an ABI element: perf_event_attr::precise, which indicates that we
wish to use this (constrained, but precise) mode.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arnaldo Carvalho de Melo <acme@infradead.org>
Cc: paulus@samba.org
Cc: eranian@google.com
Cc: robert.richter@amd.com
Cc: fweisbec@gmail.com
LKML-Reference: <20100304140100.392111285@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-03-02 18:52:12 +00:00
|
|
|
|
|
|
|
if (!(config & ARCH_PERFMON_EVENTSEL_USR))
|
2010-03-25 13:51:49 +00:00
|
|
|
debugctlmsr |= DEBUGCTLMSR_BTS_OFF_USR;
|
perf, x86: Add PEBS infrastructure
This patch implements support for Intel Precise Event Based Sampling,
which is an alternative counter mode in which the counter triggers a
hardware assist to collect information on events. The hardware assist
takes a trap like snapshot of a subset of the machine registers.
This data is written to the Intel Debug-Store, which can be programmed
with a data threshold at which to raise a PMI.
With the PEBS hardware assist being trap like, the reported IP is always
one instruction after the actual instruction that triggered the event.
This implements a simple PEBS model that always takes a single PEBS event
at a time. This is done so that the interaction with the rest of the
system is as expected (freq adjust, period randomization, lbr,
callchains, etc.).
It adds an ABI element: perf_event_attr::precise, which indicates that we
wish to use this (constrained, but precise) mode.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arnaldo Carvalho de Melo <acme@infradead.org>
Cc: paulus@samba.org
Cc: eranian@google.com
Cc: robert.richter@amd.com
Cc: fweisbec@gmail.com
LKML-Reference: <20100304140100.392111285@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-03-02 18:52:12 +00:00
|
|
|
|
|
|
|
update_debugctlmsr(debugctlmsr);
|
|
|
|
}
|
|
|
|
|
2011-08-30 23:41:05 +00:00
|
|
|
void intel_pmu_disable_bts(void)
|
perf, x86: Add PEBS infrastructure
This patch implements support for Intel Precise Event Based Sampling,
which is an alternative counter mode in which the counter triggers a
hardware assist to collect information on events. The hardware assist
takes a trap like snapshot of a subset of the machine registers.
This data is written to the Intel Debug-Store, which can be programmed
with a data threshold at which to raise a PMI.
With the PEBS hardware assist being trap like, the reported IP is always
one instruction after the actual instruction that triggered the event.
This implements a simple PEBS model that always takes a single PEBS event
at a time. This is done so that the interaction with the rest of the
system is as expected (freq adjust, period randomization, lbr,
callchains, etc.).
It adds an ABI element: perf_event_attr::precise, which indicates that we
wish to use this (constrained, but precise) mode.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arnaldo Carvalho de Melo <acme@infradead.org>
Cc: paulus@samba.org
Cc: eranian@google.com
Cc: robert.richter@amd.com
Cc: fweisbec@gmail.com
LKML-Reference: <20100304140100.392111285@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-03-02 18:52:12 +00:00
|
|
|
{
|
|
|
|
struct cpu_hw_events *cpuc = &__get_cpu_var(cpu_hw_events);
|
|
|
|
unsigned long debugctlmsr;
|
|
|
|
|
|
|
|
if (!cpuc->ds)
|
|
|
|
return;
|
|
|
|
|
|
|
|
debugctlmsr = get_debugctlmsr();
|
|
|
|
|
|
|
|
debugctlmsr &=
|
2010-03-25 13:51:49 +00:00
|
|
|
~(DEBUGCTLMSR_TR | DEBUGCTLMSR_BTS | DEBUGCTLMSR_BTINT |
|
|
|
|
DEBUGCTLMSR_BTS_OFF_OS | DEBUGCTLMSR_BTS_OFF_USR);
|
perf, x86: Add PEBS infrastructure
This patch implements support for Intel Precise Event Based Sampling,
which is an alternative counter mode in which the counter triggers a
hardware assist to collect information on events. The hardware assist
takes a trap like snapshot of a subset of the machine registers.
This data is written to the Intel Debug-Store, which can be programmed
with a data threshold at which to raise a PMI.
With the PEBS hardware assist being trap like, the reported IP is always
one instruction after the actual instruction that triggered the event.
This implements a simple PEBS model that always takes a single PEBS event
at a time. This is done so that the interaction with the rest of the
system is as expected (freq adjust, period randomization, lbr,
callchains, etc.).
It adds an ABI element: perf_event_attr::precise, which indicates that we
wish to use this (constrained, but precise) mode.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arnaldo Carvalho de Melo <acme@infradead.org>
Cc: paulus@samba.org
Cc: eranian@google.com
Cc: robert.richter@amd.com
Cc: fweisbec@gmail.com
LKML-Reference: <20100304140100.392111285@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-03-02 18:52:12 +00:00
|
|
|
|
|
|
|
update_debugctlmsr(debugctlmsr);
|
|
|
|
}
|
|
|
|
|
2011-08-30 23:41:05 +00:00
|
|
|
int intel_pmu_drain_bts_buffer(void)
|
perf, x86: Add PEBS infrastructure
This patch implements support for Intel Precise Event Based Sampling,
which is an alternative counter mode in which the counter triggers a
hardware assist to collect information on events. The hardware assist
takes a trap like snapshot of a subset of the machine registers.
This data is written to the Intel Debug-Store, which can be programmed
with a data threshold at which to raise a PMI.
With the PEBS hardware assist being trap like, the reported IP is always
one instruction after the actual instruction that triggered the event.
This implements a simple PEBS model that always takes a single PEBS event
at a time. This is done so that the interaction with the rest of the
system is as expected (freq adjust, period randomization, lbr,
callchains, etc.).
It adds an ABI element: perf_event_attr::precise, which indicates that we
wish to use this (constrained, but precise) mode.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arnaldo Carvalho de Melo <acme@infradead.org>
Cc: paulus@samba.org
Cc: eranian@google.com
Cc: robert.richter@amd.com
Cc: fweisbec@gmail.com
LKML-Reference: <20100304140100.392111285@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-03-02 18:52:12 +00:00
|
|
|
{
|
|
|
|
struct cpu_hw_events *cpuc = &__get_cpu_var(cpu_hw_events);
|
|
|
|
struct debug_store *ds = cpuc->ds;
|
|
|
|
struct bts_record {
|
|
|
|
u64 from;
|
|
|
|
u64 to;
|
|
|
|
u64 flags;
|
|
|
|
};
|
2012-06-20 18:46:33 +00:00
|
|
|
struct perf_event *event = cpuc->events[INTEL_PMC_IDX_FIXED_BTS];
|
perf, x86: Add PEBS infrastructure
This patch implements support for Intel Precise Event Based Sampling,
which is an alternative counter mode in which the counter triggers a
hardware assist to collect information on events. The hardware assist
takes a trap like snapshot of a subset of the machine registers.
This data is written to the Intel Debug-Store, which can be programmed
with a data threshold at which to raise a PMI.
With the PEBS hardware assist being trap like, the reported IP is always
one instruction after the actual instruction that triggered the event.
This implements a simple PEBS model that always takes a single PEBS event
at a time. This is done so that the interaction with the rest of the
system is as expected (freq adjust, period randomization, lbr,
callchains, etc.).
It adds an ABI element: perf_event_attr::precise, which indicates that we
wish to use this (constrained, but precise) mode.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arnaldo Carvalho de Melo <acme@infradead.org>
Cc: paulus@samba.org
Cc: eranian@google.com
Cc: robert.richter@amd.com
Cc: fweisbec@gmail.com
LKML-Reference: <20100304140100.392111285@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-03-02 18:52:12 +00:00
|
|
|
struct bts_record *at, *top;
|
|
|
|
struct perf_output_handle handle;
|
|
|
|
struct perf_event_header header;
|
|
|
|
struct perf_sample_data data;
|
|
|
|
struct pt_regs regs;
|
|
|
|
|
|
|
|
if (!event)
|
2010-09-10 11:28:01 +00:00
|
|
|
return 0;
|
perf, x86: Add PEBS infrastructure
This patch implements support for Intel Precise Event Based Sampling,
which is an alternative counter mode in which the counter triggers a
hardware assist to collect information on events. The hardware assist
takes a trap like snapshot of a subset of the machine registers.
This data is written to the Intel Debug-Store, which can be programmed
with a data threshold at which to raise a PMI.
With the PEBS hardware assist being trap like, the reported IP is always
one instruction after the actual instruction that triggered the event.
This implements a simple PEBS model that always takes a single PEBS event
at a time. This is done so that the interaction with the rest of the
system is as expected (freq adjust, period randomization, lbr,
callchains, etc.).
It adds an ABI element: perf_event_attr::precise, which indicates that we
wish to use this (constrained, but precise) mode.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arnaldo Carvalho de Melo <acme@infradead.org>
Cc: paulus@samba.org
Cc: eranian@google.com
Cc: robert.richter@amd.com
Cc: fweisbec@gmail.com
LKML-Reference: <20100304140100.392111285@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-03-02 18:52:12 +00:00
|
|
|
|
2010-10-19 12:22:50 +00:00
|
|
|
if (!x86_pmu.bts_active)
|
2010-09-10 11:28:01 +00:00
|
|
|
return 0;
|
perf, x86: Add PEBS infrastructure
This patch implements support for Intel Precise Event Based Sampling,
which is an alternative counter mode in which the counter triggers a
hardware assist to collect information on events. The hardware assist
takes a trap like snapshot of a subset of the machine registers.
This data is written to the Intel Debug-Store, which can be programmed
with a data threshold at which to raise a PMI.
With the PEBS hardware assist being trap like, the reported IP is always
one instruction after the actual instruction that triggered the event.
This implements a simple PEBS model that always takes a single PEBS event
at a time. This is done so that the interaction with the rest of the
system is as expected (freq adjust, period randomization, lbr,
callchains, etc.).
It adds an ABI element: perf_event_attr::precise, which indicates that we
wish to use this (constrained, but precise) mode.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arnaldo Carvalho de Melo <acme@infradead.org>
Cc: paulus@samba.org
Cc: eranian@google.com
Cc: robert.richter@amd.com
Cc: fweisbec@gmail.com
LKML-Reference: <20100304140100.392111285@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-03-02 18:52:12 +00:00
|
|
|
|
|
|
|
at = (struct bts_record *)(unsigned long)ds->bts_buffer_base;
|
|
|
|
top = (struct bts_record *)(unsigned long)ds->bts_index;
|
|
|
|
|
|
|
|
if (top <= at)
|
2010-09-10 11:28:01 +00:00
|
|
|
return 0;
|
perf, x86: Add PEBS infrastructure
This patch implements support for Intel Precise Event Based Sampling,
which is an alternative counter mode in which the counter triggers a
hardware assist to collect information on events. The hardware assist
takes a trap like snapshot of a subset of the machine registers.
This data is written to the Intel Debug-Store, which can be programmed
with a data threshold at which to raise a PMI.
With the PEBS hardware assist being trap like, the reported IP is always
one instruction after the actual instruction that triggered the event.
This implements a simple PEBS model that always takes a single PEBS event
at a time. This is done so that the interaction with the rest of the
system is as expected (freq adjust, period randomization, lbr,
callchains, etc.).
It adds an ABI element: perf_event_attr::precise, which indicates that we
wish to use this (constrained, but precise) mode.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arnaldo Carvalho de Melo <acme@infradead.org>
Cc: paulus@samba.org
Cc: eranian@google.com
Cc: robert.richter@amd.com
Cc: fweisbec@gmail.com
LKML-Reference: <20100304140100.392111285@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-03-02 18:52:12 +00:00
|
|
|
|
2013-03-19 15:10:38 +00:00
|
|
|
memset(®s, 0, sizeof(regs));
|
|
|
|
|
perf, x86: Add PEBS infrastructure
This patch implements support for Intel Precise Event Based Sampling,
which is an alternative counter mode in which the counter triggers a
hardware assist to collect information on events. The hardware assist
takes a trap like snapshot of a subset of the machine registers.
This data is written to the Intel Debug-Store, which can be programmed
with a data threshold at which to raise a PMI.
With the PEBS hardware assist being trap like, the reported IP is always
one instruction after the actual instruction that triggered the event.
This implements a simple PEBS model that always takes a single PEBS event
at a time. This is done so that the interaction with the rest of the
system is as expected (freq adjust, period randomization, lbr,
callchains, etc.).
It adds an ABI element: perf_event_attr::precise, which indicates that we
wish to use this (constrained, but precise) mode.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arnaldo Carvalho de Melo <acme@infradead.org>
Cc: paulus@samba.org
Cc: eranian@google.com
Cc: robert.richter@amd.com
Cc: fweisbec@gmail.com
LKML-Reference: <20100304140100.392111285@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-03-02 18:52:12 +00:00
|
|
|
ds->bts_index = ds->bts_buffer_base;
|
|
|
|
|
2012-04-02 18:19:08 +00:00
|
|
|
perf_sample_data_init(&data, 0, event->hw.last_period);
|
perf, x86: Add PEBS infrastructure
This patch implements support for Intel Precise Event Based Sampling,
which is an alternative counter mode in which the counter triggers a
hardware assist to collect information on events. The hardware assist
takes a trap like snapshot of a subset of the machine registers.
This data is written to the Intel Debug-Store, which can be programmed
with a data threshold at which to raise a PMI.
With the PEBS hardware assist being trap like, the reported IP is always
one instruction after the actual instruction that triggered the event.
This implements a simple PEBS model that always takes a single PEBS event
at a time. This is done so that the interaction with the rest of the
system is as expected (freq adjust, period randomization, lbr,
callchains, etc.).
It adds an ABI element: perf_event_attr::precise, which indicates that we
wish to use this (constrained, but precise) mode.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arnaldo Carvalho de Melo <acme@infradead.org>
Cc: paulus@samba.org
Cc: eranian@google.com
Cc: robert.richter@amd.com
Cc: fweisbec@gmail.com
LKML-Reference: <20100304140100.392111285@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-03-02 18:52:12 +00:00
|
|
|
|
|
|
|
/*
|
|
|
|
* Prepare a generic sample, i.e. fill in the invariant fields.
|
|
|
|
* We will overwrite the from and to address before we output
|
|
|
|
* the sample.
|
|
|
|
*/
|
|
|
|
perf_prepare_sample(&header, &data, event, ®s);
|
|
|
|
|
2011-06-27 14:47:16 +00:00
|
|
|
if (perf_output_begin(&handle, event, header.size * (top - at)))
|
2010-09-10 11:28:01 +00:00
|
|
|
return 1;
|
perf, x86: Add PEBS infrastructure
This patch implements support for Intel Precise Event Based Sampling,
which is an alternative counter mode in which the counter triggers a
hardware assist to collect information on events. The hardware assist
takes a trap like snapshot of a subset of the machine registers.
This data is written to the Intel Debug-Store, which can be programmed
with a data threshold at which to raise a PMI.
With the PEBS hardware assist being trap like, the reported IP is always
one instruction after the actual instruction that triggered the event.
This implements a simple PEBS model that always takes a single PEBS event
at a time. This is done so that the interaction with the rest of the
system is as expected (freq adjust, period randomization, lbr,
callchains, etc.).
It adds an ABI element: perf_event_attr::precise, which indicates that we
wish to use this (constrained, but precise) mode.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arnaldo Carvalho de Melo <acme@infradead.org>
Cc: paulus@samba.org
Cc: eranian@google.com
Cc: robert.richter@amd.com
Cc: fweisbec@gmail.com
LKML-Reference: <20100304140100.392111285@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-03-02 18:52:12 +00:00
|
|
|
|
|
|
|
for (; at < top; at++) {
|
|
|
|
data.ip = at->from;
|
|
|
|
data.addr = at->to;
|
|
|
|
|
|
|
|
perf_output_sample(&handle, &header, &data, event);
|
|
|
|
}
|
|
|
|
|
|
|
|
perf_output_end(&handle);
|
|
|
|
|
|
|
|
/* There's new data available. */
|
|
|
|
event->hw.interrupts++;
|
|
|
|
event->pending_kill = POLL_IN;
|
2010-09-10 11:28:01 +00:00
|
|
|
return 1;
|
perf, x86: Add PEBS infrastructure
This patch implements support for Intel Precise Event Based Sampling,
which is an alternative counter mode in which the counter triggers a
hardware assist to collect information on events. The hardware assist
takes a trap like snapshot of a subset of the machine registers.
This data is written to the Intel Debug-Store, which can be programmed
with a data threshold at which to raise a PMI.
With the PEBS hardware assist being trap like, the reported IP is always
one instruction after the actual instruction that triggered the event.
This implements a simple PEBS model that always takes a single PEBS event
at a time. This is done so that the interaction with the rest of the
system is as expected (freq adjust, period randomization, lbr,
callchains, etc.).
It adds an ABI element: perf_event_attr::precise, which indicates that we
wish to use this (constrained, but precise) mode.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arnaldo Carvalho de Melo <acme@infradead.org>
Cc: paulus@samba.org
Cc: eranian@google.com
Cc: robert.richter@amd.com
Cc: fweisbec@gmail.com
LKML-Reference: <20100304140100.392111285@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-03-02 18:52:12 +00:00
|
|
|
}
|
|
|
|
|
|
|
|
/*
|
|
|
|
* PEBS
|
|
|
|
*/
|
2011-08-30 23:41:05 +00:00
|
|
|
struct event_constraint intel_core2_pebs_event_constraints[] = {
|
2011-03-09 15:21:29 +00:00
|
|
|
INTEL_UEVENT_CONSTRAINT(0x00c0, 0x1), /* INST_RETIRED.ANY */
|
|
|
|
INTEL_UEVENT_CONSTRAINT(0xfec1, 0x1), /* X87_OPS_RETIRED.ANY */
|
|
|
|
INTEL_UEVENT_CONSTRAINT(0x00c5, 0x1), /* BR_INST_RETIRED.MISPRED */
|
|
|
|
INTEL_UEVENT_CONSTRAINT(0x1fc7, 0x1), /* SIMD_INST_RETURED.ANY */
|
|
|
|
INTEL_EVENT_CONSTRAINT(0xcb, 0x1), /* MEM_LOAD_RETIRED.* */
|
perf, x86: Add PEBS infrastructure
This patch implements support for Intel Precise Event Based Sampling,
which is an alternative counter mode in which the counter triggers a
hardware assist to collect information on events. The hardware assist
takes a trap like snapshot of a subset of the machine registers.
This data is written to the Intel Debug-Store, which can be programmed
with a data threshold at which to raise a PMI.
With the PEBS hardware assist being trap like, the reported IP is always
one instruction after the actual instruction that triggered the event.
This implements a simple PEBS model that always takes a single PEBS event
at a time. This is done so that the interaction with the rest of the
system is as expected (freq adjust, period randomization, lbr,
callchains, etc.).
It adds an ABI element: perf_event_attr::precise, which indicates that we
wish to use this (constrained, but precise) mode.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arnaldo Carvalho de Melo <acme@infradead.org>
Cc: paulus@samba.org
Cc: eranian@google.com
Cc: robert.richter@amd.com
Cc: fweisbec@gmail.com
LKML-Reference: <20100304140100.392111285@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-03-02 18:52:12 +00:00
|
|
|
EVENT_CONSTRAINT_END
|
|
|
|
};
|
|
|
|
|
2011-08-30 23:41:05 +00:00
|
|
|
struct event_constraint intel_atom_pebs_event_constraints[] = {
|
2011-03-09 15:21:29 +00:00
|
|
|
INTEL_UEVENT_CONSTRAINT(0x00c0, 0x1), /* INST_RETIRED.ANY */
|
|
|
|
INTEL_UEVENT_CONSTRAINT(0x00c5, 0x1), /* MISPREDICTED_BRANCH_RETIRED */
|
|
|
|
INTEL_EVENT_CONSTRAINT(0xcb, 0x1), /* MEM_LOAD_RETIRED.* */
|
2011-03-02 15:05:01 +00:00
|
|
|
EVENT_CONSTRAINT_END
|
|
|
|
};
|
|
|
|
|
2013-07-18 09:02:24 +00:00
|
|
|
struct event_constraint intel_slm_pebs_event_constraints[] = {
|
2014-08-11 19:27:10 +00:00
|
|
|
/* UOPS_RETIRED.ALL, inv=1, cmask=16 (cycles:p). */
|
|
|
|
INTEL_FLAGS_EVENT_CONSTRAINT(0x108001c2, 0xf),
|
|
|
|
/* Allow all events as PEBS with no flags */
|
|
|
|
INTEL_ALL_EVENT_CONSTRAINT(0, 0x1),
|
2013-07-18 09:02:24 +00:00
|
|
|
EVENT_CONSTRAINT_END
|
|
|
|
};
|
|
|
|
|
2011-08-30 23:41:05 +00:00
|
|
|
struct event_constraint intel_nehalem_pebs_event_constraints[] = {
|
2013-01-24 15:10:32 +00:00
|
|
|
INTEL_PLD_CONSTRAINT(0x100b, 0xf), /* MEM_INST_RETIRED.* */
|
2011-03-09 15:21:29 +00:00
|
|
|
INTEL_EVENT_CONSTRAINT(0x0f, 0xf), /* MEM_UNCORE_RETIRED.* */
|
|
|
|
INTEL_UEVENT_CONSTRAINT(0x010c, 0xf), /* MEM_STORE_RETIRED.DTLB_MISS */
|
|
|
|
INTEL_EVENT_CONSTRAINT(0xc0, 0xf), /* INST_RETIRED.ANY */
|
|
|
|
INTEL_EVENT_CONSTRAINT(0xc2, 0xf), /* UOPS_RETIRED.* */
|
|
|
|
INTEL_EVENT_CONSTRAINT(0xc4, 0xf), /* BR_INST_RETIRED.* */
|
|
|
|
INTEL_UEVENT_CONSTRAINT(0x02c5, 0xf), /* BR_MISP_RETIRED.NEAR_CALL */
|
|
|
|
INTEL_EVENT_CONSTRAINT(0xc7, 0xf), /* SSEX_UOPS_RETIRED.* */
|
|
|
|
INTEL_UEVENT_CONSTRAINT(0x20c8, 0xf), /* ITLB_MISS_RETIRED */
|
|
|
|
INTEL_EVENT_CONSTRAINT(0xcb, 0xf), /* MEM_LOAD_RETIRED.* */
|
|
|
|
INTEL_EVENT_CONSTRAINT(0xf7, 0xf), /* FP_ASSIST.* */
|
2011-03-02 15:05:01 +00:00
|
|
|
EVENT_CONSTRAINT_END
|
|
|
|
};
|
|
|
|
|
2011-08-30 23:41:05 +00:00
|
|
|
struct event_constraint intel_westmere_pebs_event_constraints[] = {
|
2013-01-24 15:10:32 +00:00
|
|
|
INTEL_PLD_CONSTRAINT(0x100b, 0xf), /* MEM_INST_RETIRED.* */
|
2011-03-09 15:21:29 +00:00
|
|
|
INTEL_EVENT_CONSTRAINT(0x0f, 0xf), /* MEM_UNCORE_RETIRED.* */
|
|
|
|
INTEL_UEVENT_CONSTRAINT(0x010c, 0xf), /* MEM_STORE_RETIRED.DTLB_MISS */
|
|
|
|
INTEL_EVENT_CONSTRAINT(0xc0, 0xf), /* INSTR_RETIRED.* */
|
|
|
|
INTEL_EVENT_CONSTRAINT(0xc2, 0xf), /* UOPS_RETIRED.* */
|
|
|
|
INTEL_EVENT_CONSTRAINT(0xc4, 0xf), /* BR_INST_RETIRED.* */
|
|
|
|
INTEL_EVENT_CONSTRAINT(0xc5, 0xf), /* BR_MISP_RETIRED.* */
|
|
|
|
INTEL_EVENT_CONSTRAINT(0xc7, 0xf), /* SSEX_UOPS_RETIRED.* */
|
|
|
|
INTEL_UEVENT_CONSTRAINT(0x20c8, 0xf), /* ITLB_MISS_RETIRED */
|
|
|
|
INTEL_EVENT_CONSTRAINT(0xcb, 0xf), /* MEM_LOAD_RETIRED.* */
|
|
|
|
INTEL_EVENT_CONSTRAINT(0xf7, 0xf), /* FP_ASSIST.* */
|
perf, x86: Add PEBS infrastructure
This patch implements support for Intel Precise Event Based Sampling,
which is an alternative counter mode in which the counter triggers a
hardware assist to collect information on events. The hardware assist
takes a trap like snapshot of a subset of the machine registers.
This data is written to the Intel Debug-Store, which can be programmed
with a data threshold at which to raise a PMI.
With the PEBS hardware assist being trap like, the reported IP is always
one instruction after the actual instruction that triggered the event.
This implements a simple PEBS model that always takes a single PEBS event
at a time. This is done so that the interaction with the rest of the
system is as expected (freq adjust, period randomization, lbr,
callchains, etc.).
It adds an ABI element: perf_event_attr::precise, which indicates that we
wish to use this (constrained, but precise) mode.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arnaldo Carvalho de Melo <acme@infradead.org>
Cc: paulus@samba.org
Cc: eranian@google.com
Cc: robert.richter@amd.com
Cc: fweisbec@gmail.com
LKML-Reference: <20100304140100.392111285@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-03-02 18:52:12 +00:00
|
|
|
EVENT_CONSTRAINT_END
|
|
|
|
};
|
|
|
|
|
2011-08-30 23:41:05 +00:00
|
|
|
struct event_constraint intel_snb_pebs_event_constraints[] = {
|
2011-03-09 15:21:29 +00:00
|
|
|
INTEL_UEVENT_CONSTRAINT(0x01c0, 0x2), /* INST_RETIRED.PRECDIST */
|
2013-01-24 15:10:32 +00:00
|
|
|
INTEL_PLD_CONSTRAINT(0x01cd, 0x8), /* MEM_TRANS_RETIRED.LAT_ABOVE_THR */
|
2013-01-24 15:10:34 +00:00
|
|
|
INTEL_PST_CONSTRAINT(0x02cd, 0x8), /* MEM_TRANS_RETIRED.PRECISE_STORES */
|
2014-08-11 19:27:10 +00:00
|
|
|
/* UOPS_RETIRED.ALL, inv=1, cmask=16 (cycles:p). */
|
|
|
|
INTEL_FLAGS_EVENT_CONSTRAINT(0x108001c2, 0xf),
|
|
|
|
/* Allow all events as PEBS with no flags */
|
|
|
|
INTEL_ALL_EVENT_CONSTRAINT(0, 0xf),
|
2011-03-02 13:27:04 +00:00
|
|
|
EVENT_CONSTRAINT_END
|
|
|
|
};
|
|
|
|
|
2012-09-10 23:07:01 +00:00
|
|
|
struct event_constraint intel_ivb_pebs_event_constraints[] = {
|
|
|
|
INTEL_UEVENT_CONSTRAINT(0x01c0, 0x2), /* INST_RETIRED.PRECDIST */
|
2013-01-24 15:10:32 +00:00
|
|
|
INTEL_PLD_CONSTRAINT(0x01cd, 0x8), /* MEM_TRANS_RETIRED.LAT_ABOVE_THR */
|
2013-01-24 15:10:34 +00:00
|
|
|
INTEL_PST_CONSTRAINT(0x02cd, 0x8), /* MEM_TRANS_RETIRED.PRECISE_STORES */
|
2014-08-11 19:27:10 +00:00
|
|
|
/* UOPS_RETIRED.ALL, inv=1, cmask=16 (cycles:p). */
|
|
|
|
INTEL_FLAGS_EVENT_CONSTRAINT(0x108001c2, 0xf),
|
|
|
|
/* Allow all events as PEBS with no flags */
|
|
|
|
INTEL_ALL_EVENT_CONSTRAINT(0, 0xf),
|
2012-09-10 23:07:01 +00:00
|
|
|
EVENT_CONSTRAINT_END
|
|
|
|
};
|
|
|
|
|
2013-06-18 00:36:49 +00:00
|
|
|
struct event_constraint intel_hsw_pebs_event_constraints[] = {
|
|
|
|
INTEL_UEVENT_CONSTRAINT(0x01c0, 0x2), /* INST_RETIRED.PRECDIST */
|
2014-08-11 19:27:10 +00:00
|
|
|
INTEL_PLD_CONSTRAINT(0x01cd, 0xf), /* MEM_TRANS_RETIRED.* */
|
|
|
|
/* UOPS_RETIRED.ALL, inv=1, cmask=16 (cycles:p). */
|
|
|
|
INTEL_FLAGS_EVENT_CONSTRAINT(0x108001c2, 0xf),
|
|
|
|
INTEL_FLAGS_UEVENT_CONSTRAINT_DATALA_NA(0x01c2, 0xf), /* UOPS_RETIRED.ALL */
|
|
|
|
INTEL_FLAGS_UEVENT_CONSTRAINT_DATALA_LD(0x11d0, 0xf), /* MEM_UOPS_RETIRED.STLB_MISS_LOADS */
|
|
|
|
INTEL_FLAGS_UEVENT_CONSTRAINT_DATALA_LD(0x21d0, 0xf), /* MEM_UOPS_RETIRED.LOCK_LOADS */
|
|
|
|
INTEL_FLAGS_UEVENT_CONSTRAINT_DATALA_LD(0x41d0, 0xf), /* MEM_UOPS_RETIRED.SPLIT_LOADS */
|
|
|
|
INTEL_FLAGS_UEVENT_CONSTRAINT_DATALA_LD(0x81d0, 0xf), /* MEM_UOPS_RETIRED.ALL_LOADS */
|
|
|
|
INTEL_FLAGS_UEVENT_CONSTRAINT_DATALA_ST(0x12d0, 0xf), /* MEM_UOPS_RETIRED.STLB_MISS_STORES */
|
|
|
|
INTEL_FLAGS_UEVENT_CONSTRAINT_DATALA_ST(0x42d0, 0xf), /* MEM_UOPS_RETIRED.SPLIT_STORES */
|
|
|
|
INTEL_FLAGS_UEVENT_CONSTRAINT_DATALA_ST(0x82d0, 0xf), /* MEM_UOPS_RETIRED.ALL_STORES */
|
|
|
|
INTEL_FLAGS_EVENT_CONSTRAINT_DATALA_LD(0xd1, 0xf), /* MEM_LOAD_UOPS_RETIRED.* */
|
|
|
|
INTEL_FLAGS_EVENT_CONSTRAINT_DATALA_LD(0xd2, 0xf), /* MEM_LOAD_UOPS_L3_HIT_RETIRED.* */
|
|
|
|
INTEL_FLAGS_EVENT_CONSTRAINT_DATALA_LD(0xd3, 0xf), /* MEM_LOAD_UOPS_L3_MISS_RETIRED.* */
|
|
|
|
/* Allow all events as PEBS with no flags */
|
|
|
|
INTEL_ALL_EVENT_CONSTRAINT(0, 0xf),
|
2013-06-18 00:36:49 +00:00
|
|
|
EVENT_CONSTRAINT_END
|
|
|
|
};
|
|
|
|
|
2011-08-30 23:41:05 +00:00
|
|
|
struct event_constraint *intel_pebs_constraints(struct perf_event *event)
|
perf, x86: Add PEBS infrastructure
This patch implements support for Intel Precise Event Based Sampling,
which is an alternative counter mode in which the counter triggers a
hardware assist to collect information on events. The hardware assist
takes a trap like snapshot of a subset of the machine registers.
This data is written to the Intel Debug-Store, which can be programmed
with a data threshold at which to raise a PMI.
With the PEBS hardware assist being trap like, the reported IP is always
one instruction after the actual instruction that triggered the event.
This implements a simple PEBS model that always takes a single PEBS event
at a time. This is done so that the interaction with the rest of the
system is as expected (freq adjust, period randomization, lbr,
callchains, etc.).
It adds an ABI element: perf_event_attr::precise, which indicates that we
wish to use this (constrained, but precise) mode.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arnaldo Carvalho de Melo <acme@infradead.org>
Cc: paulus@samba.org
Cc: eranian@google.com
Cc: robert.richter@amd.com
Cc: fweisbec@gmail.com
LKML-Reference: <20100304140100.392111285@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-03-02 18:52:12 +00:00
|
|
|
{
|
|
|
|
struct event_constraint *c;
|
|
|
|
|
2010-04-08 21:03:20 +00:00
|
|
|
if (!event->attr.precise_ip)
|
perf, x86: Add PEBS infrastructure
This patch implements support for Intel Precise Event Based Sampling,
which is an alternative counter mode in which the counter triggers a
hardware assist to collect information on events. The hardware assist
takes a trap like snapshot of a subset of the machine registers.
This data is written to the Intel Debug-Store, which can be programmed
with a data threshold at which to raise a PMI.
With the PEBS hardware assist being trap like, the reported IP is always
one instruction after the actual instruction that triggered the event.
This implements a simple PEBS model that always takes a single PEBS event
at a time. This is done so that the interaction with the rest of the
system is as expected (freq adjust, period randomization, lbr,
callchains, etc.).
It adds an ABI element: perf_event_attr::precise, which indicates that we
wish to use this (constrained, but precise) mode.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arnaldo Carvalho de Melo <acme@infradead.org>
Cc: paulus@samba.org
Cc: eranian@google.com
Cc: robert.richter@amd.com
Cc: fweisbec@gmail.com
LKML-Reference: <20100304140100.392111285@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-03-02 18:52:12 +00:00
|
|
|
return NULL;
|
|
|
|
|
|
|
|
if (x86_pmu.pebs_constraints) {
|
|
|
|
for_each_event_constraint(c, x86_pmu.pebs_constraints) {
|
2013-01-24 15:10:27 +00:00
|
|
|
if ((event->hw.config & c->cmask) == c->code) {
|
|
|
|
event->hw.flags |= c->flags;
|
perf, x86: Add PEBS infrastructure
This patch implements support for Intel Precise Event Based Sampling,
which is an alternative counter mode in which the counter triggers a
hardware assist to collect information on events. The hardware assist
takes a trap like snapshot of a subset of the machine registers.
This data is written to the Intel Debug-Store, which can be programmed
with a data threshold at which to raise a PMI.
With the PEBS hardware assist being trap like, the reported IP is always
one instruction after the actual instruction that triggered the event.
This implements a simple PEBS model that always takes a single PEBS event
at a time. This is done so that the interaction with the rest of the
system is as expected (freq adjust, period randomization, lbr,
callchains, etc.).
It adds an ABI element: perf_event_attr::precise, which indicates that we
wish to use this (constrained, but precise) mode.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arnaldo Carvalho de Melo <acme@infradead.org>
Cc: paulus@samba.org
Cc: eranian@google.com
Cc: robert.richter@amd.com
Cc: fweisbec@gmail.com
LKML-Reference: <20100304140100.392111285@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-03-02 18:52:12 +00:00
|
|
|
return c;
|
2013-01-24 15:10:27 +00:00
|
|
|
}
|
perf, x86: Add PEBS infrastructure
This patch implements support for Intel Precise Event Based Sampling,
which is an alternative counter mode in which the counter triggers a
hardware assist to collect information on events. The hardware assist
takes a trap like snapshot of a subset of the machine registers.
This data is written to the Intel Debug-Store, which can be programmed
with a data threshold at which to raise a PMI.
With the PEBS hardware assist being trap like, the reported IP is always
one instruction after the actual instruction that triggered the event.
This implements a simple PEBS model that always takes a single PEBS event
at a time. This is done so that the interaction with the rest of the
system is as expected (freq adjust, period randomization, lbr,
callchains, etc.).
It adds an ABI element: perf_event_attr::precise, which indicates that we
wish to use this (constrained, but precise) mode.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arnaldo Carvalho de Melo <acme@infradead.org>
Cc: paulus@samba.org
Cc: eranian@google.com
Cc: robert.richter@amd.com
Cc: fweisbec@gmail.com
LKML-Reference: <20100304140100.392111285@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-03-02 18:52:12 +00:00
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
return &emptyconstraint;
|
|
|
|
}
|
|
|
|
|
2011-08-30 23:41:05 +00:00
|
|
|
void intel_pmu_pebs_enable(struct perf_event *event)
|
perf, x86: Add PEBS infrastructure
This patch implements support for Intel Precise Event Based Sampling,
which is an alternative counter mode in which the counter triggers a
hardware assist to collect information on events. The hardware assist
takes a trap like snapshot of a subset of the machine registers.
This data is written to the Intel Debug-Store, which can be programmed
with a data threshold at which to raise a PMI.
With the PEBS hardware assist being trap like, the reported IP is always
one instruction after the actual instruction that triggered the event.
This implements a simple PEBS model that always takes a single PEBS event
at a time. This is done so that the interaction with the rest of the
system is as expected (freq adjust, period randomization, lbr,
callchains, etc.).
It adds an ABI element: perf_event_attr::precise, which indicates that we
wish to use this (constrained, but precise) mode.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arnaldo Carvalho de Melo <acme@infradead.org>
Cc: paulus@samba.org
Cc: eranian@google.com
Cc: robert.richter@amd.com
Cc: fweisbec@gmail.com
LKML-Reference: <20100304140100.392111285@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-03-02 18:52:12 +00:00
|
|
|
{
|
|
|
|
struct cpu_hw_events *cpuc = &__get_cpu_var(cpu_hw_events);
|
2010-03-03 12:12:23 +00:00
|
|
|
struct hw_perf_event *hwc = &event->hw;
|
perf, x86: Add PEBS infrastructure
This patch implements support for Intel Precise Event Based Sampling,
which is an alternative counter mode in which the counter triggers a
hardware assist to collect information on events. The hardware assist
takes a trap like snapshot of a subset of the machine registers.
This data is written to the Intel Debug-Store, which can be programmed
with a data threshold at which to raise a PMI.
With the PEBS hardware assist being trap like, the reported IP is always
one instruction after the actual instruction that triggered the event.
This implements a simple PEBS model that always takes a single PEBS event
at a time. This is done so that the interaction with the rest of the
system is as expected (freq adjust, period randomization, lbr,
callchains, etc.).
It adds an ABI element: perf_event_attr::precise, which indicates that we
wish to use this (constrained, but precise) mode.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arnaldo Carvalho de Melo <acme@infradead.org>
Cc: paulus@samba.org
Cc: eranian@google.com
Cc: robert.richter@amd.com
Cc: fweisbec@gmail.com
LKML-Reference: <20100304140100.392111285@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-03-02 18:52:12 +00:00
|
|
|
|
|
|
|
hwc->config &= ~ARCH_PERFMON_EVENTSEL_INT;
|
|
|
|
|
2010-03-06 18:49:06 +00:00
|
|
|
cpuc->pebs_enabled |= 1ULL << hwc->idx;
|
2013-01-24 15:10:32 +00:00
|
|
|
|
|
|
|
if (event->hw.flags & PERF_X86_EVENT_PEBS_LDLAT)
|
|
|
|
cpuc->pebs_enabled |= 1ULL << (hwc->idx + 32);
|
2013-01-24 15:10:34 +00:00
|
|
|
else if (event->hw.flags & PERF_X86_EVENT_PEBS_ST)
|
|
|
|
cpuc->pebs_enabled |= 1ULL << 63;
|
perf, x86: Add PEBS infrastructure
This patch implements support for Intel Precise Event Based Sampling,
which is an alternative counter mode in which the counter triggers a
hardware assist to collect information on events. The hardware assist
takes a trap like snapshot of a subset of the machine registers.
This data is written to the Intel Debug-Store, which can be programmed
with a data threshold at which to raise a PMI.
With the PEBS hardware assist being trap like, the reported IP is always
one instruction after the actual instruction that triggered the event.
This implements a simple PEBS model that always takes a single PEBS event
at a time. This is done so that the interaction with the rest of the
system is as expected (freq adjust, period randomization, lbr,
callchains, etc.).
It adds an ABI element: perf_event_attr::precise, which indicates that we
wish to use this (constrained, but precise) mode.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arnaldo Carvalho de Melo <acme@infradead.org>
Cc: paulus@samba.org
Cc: eranian@google.com
Cc: robert.richter@amd.com
Cc: fweisbec@gmail.com
LKML-Reference: <20100304140100.392111285@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-03-02 18:52:12 +00:00
|
|
|
}
|
|
|
|
|
2011-08-30 23:41:05 +00:00
|
|
|
void intel_pmu_pebs_disable(struct perf_event *event)
|
perf, x86: Add PEBS infrastructure
This patch implements support for Intel Precise Event Based Sampling,
which is an alternative counter mode in which the counter triggers a
hardware assist to collect information on events. The hardware assist
takes a trap like snapshot of a subset of the machine registers.
This data is written to the Intel Debug-Store, which can be programmed
with a data threshold at which to raise a PMI.
With the PEBS hardware assist being trap like, the reported IP is always
one instruction after the actual instruction that triggered the event.
This implements a simple PEBS model that always takes a single PEBS event
at a time. This is done so that the interaction with the rest of the
system is as expected (freq adjust, period randomization, lbr,
callchains, etc.).
It adds an ABI element: perf_event_attr::precise, which indicates that we
wish to use this (constrained, but precise) mode.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arnaldo Carvalho de Melo <acme@infradead.org>
Cc: paulus@samba.org
Cc: eranian@google.com
Cc: robert.richter@amd.com
Cc: fweisbec@gmail.com
LKML-Reference: <20100304140100.392111285@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-03-02 18:52:12 +00:00
|
|
|
{
|
|
|
|
struct cpu_hw_events *cpuc = &__get_cpu_var(cpu_hw_events);
|
2010-03-03 12:12:23 +00:00
|
|
|
struct hw_perf_event *hwc = &event->hw;
|
perf, x86: Add PEBS infrastructure
This patch implements support for Intel Precise Event Based Sampling,
which is an alternative counter mode in which the counter triggers a
hardware assist to collect information on events. The hardware assist
takes a trap like snapshot of a subset of the machine registers.
This data is written to the Intel Debug-Store, which can be programmed
with a data threshold at which to raise a PMI.
With the PEBS hardware assist being trap like, the reported IP is always
one instruction after the actual instruction that triggered the event.
This implements a simple PEBS model that always takes a single PEBS event
at a time. This is done so that the interaction with the rest of the
system is as expected (freq adjust, period randomization, lbr,
callchains, etc.).
It adds an ABI element: perf_event_attr::precise, which indicates that we
wish to use this (constrained, but precise) mode.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arnaldo Carvalho de Melo <acme@infradead.org>
Cc: paulus@samba.org
Cc: eranian@google.com
Cc: robert.richter@amd.com
Cc: fweisbec@gmail.com
LKML-Reference: <20100304140100.392111285@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-03-02 18:52:12 +00:00
|
|
|
|
2010-03-06 18:49:06 +00:00
|
|
|
cpuc->pebs_enabled &= ~(1ULL << hwc->idx);
|
2013-06-21 14:20:41 +00:00
|
|
|
|
|
|
|
if (event->hw.constraint->flags & PERF_X86_EVENT_PEBS_LDLAT)
|
|
|
|
cpuc->pebs_enabled &= ~(1ULL << (hwc->idx + 32));
|
|
|
|
else if (event->hw.constraint->flags & PERF_X86_EVENT_PEBS_ST)
|
|
|
|
cpuc->pebs_enabled &= ~(1ULL << 63);
|
|
|
|
|
2010-03-06 12:47:07 +00:00
|
|
|
if (cpuc->enabled)
|
2010-03-06 18:49:06 +00:00
|
|
|
wrmsrl(MSR_IA32_PEBS_ENABLE, cpuc->pebs_enabled);
|
perf, x86: Add PEBS infrastructure
This patch implements support for Intel Precise Event Based Sampling,
which is an alternative counter mode in which the counter triggers a
hardware assist to collect information on events. The hardware assist
takes a trap like snapshot of a subset of the machine registers.
This data is written to the Intel Debug-Store, which can be programmed
with a data threshold at which to raise a PMI.
With the PEBS hardware assist being trap like, the reported IP is always
one instruction after the actual instruction that triggered the event.
This implements a simple PEBS model that always takes a single PEBS event
at a time. This is done so that the interaction with the rest of the
system is as expected (freq adjust, period randomization, lbr,
callchains, etc.).
It adds an ABI element: perf_event_attr::precise, which indicates that we
wish to use this (constrained, but precise) mode.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arnaldo Carvalho de Melo <acme@infradead.org>
Cc: paulus@samba.org
Cc: eranian@google.com
Cc: robert.richter@amd.com
Cc: fweisbec@gmail.com
LKML-Reference: <20100304140100.392111285@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-03-02 18:52:12 +00:00
|
|
|
|
|
|
|
hwc->config |= ARCH_PERFMON_EVENTSEL_INT;
|
|
|
|
}
|
|
|
|
|
2011-08-30 23:41:05 +00:00
|
|
|
void intel_pmu_pebs_enable_all(void)
|
perf, x86: Add PEBS infrastructure
This patch implements support for Intel Precise Event Based Sampling,
which is an alternative counter mode in which the counter triggers a
hardware assist to collect information on events. The hardware assist
takes a trap like snapshot of a subset of the machine registers.
This data is written to the Intel Debug-Store, which can be programmed
with a data threshold at which to raise a PMI.
With the PEBS hardware assist being trap like, the reported IP is always
one instruction after the actual instruction that triggered the event.
This implements a simple PEBS model that always takes a single PEBS event
at a time. This is done so that the interaction with the rest of the
system is as expected (freq adjust, period randomization, lbr,
callchains, etc.).
It adds an ABI element: perf_event_attr::precise, which indicates that we
wish to use this (constrained, but precise) mode.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arnaldo Carvalho de Melo <acme@infradead.org>
Cc: paulus@samba.org
Cc: eranian@google.com
Cc: robert.richter@amd.com
Cc: fweisbec@gmail.com
LKML-Reference: <20100304140100.392111285@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-03-02 18:52:12 +00:00
|
|
|
{
|
|
|
|
struct cpu_hw_events *cpuc = &__get_cpu_var(cpu_hw_events);
|
|
|
|
|
|
|
|
if (cpuc->pebs_enabled)
|
|
|
|
wrmsrl(MSR_IA32_PEBS_ENABLE, cpuc->pebs_enabled);
|
|
|
|
}
|
|
|
|
|
2011-08-30 23:41:05 +00:00
|
|
|
void intel_pmu_pebs_disable_all(void)
|
perf, x86: Add PEBS infrastructure
This patch implements support for Intel Precise Event Based Sampling,
which is an alternative counter mode in which the counter triggers a
hardware assist to collect information on events. The hardware assist
takes a trap like snapshot of a subset of the machine registers.
This data is written to the Intel Debug-Store, which can be programmed
with a data threshold at which to raise a PMI.
With the PEBS hardware assist being trap like, the reported IP is always
one instruction after the actual instruction that triggered the event.
This implements a simple PEBS model that always takes a single PEBS event
at a time. This is done so that the interaction with the rest of the
system is as expected (freq adjust, period randomization, lbr,
callchains, etc.).
It adds an ABI element: perf_event_attr::precise, which indicates that we
wish to use this (constrained, but precise) mode.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arnaldo Carvalho de Melo <acme@infradead.org>
Cc: paulus@samba.org
Cc: eranian@google.com
Cc: robert.richter@amd.com
Cc: fweisbec@gmail.com
LKML-Reference: <20100304140100.392111285@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-03-02 18:52:12 +00:00
|
|
|
{
|
|
|
|
struct cpu_hw_events *cpuc = &__get_cpu_var(cpu_hw_events);
|
|
|
|
|
|
|
|
if (cpuc->pebs_enabled)
|
|
|
|
wrmsrl(MSR_IA32_PEBS_ENABLE, 0);
|
|
|
|
}
|
|
|
|
|
2010-03-03 12:12:23 +00:00
|
|
|
static int intel_pmu_pebs_fixup_ip(struct pt_regs *regs)
|
|
|
|
{
|
|
|
|
struct cpu_hw_events *cpuc = &__get_cpu_var(cpu_hw_events);
|
|
|
|
unsigned long from = cpuc->lbr_entries[0].from;
|
|
|
|
unsigned long old_to, to = cpuc->lbr_entries[0].to;
|
|
|
|
unsigned long ip = regs->ip;
|
2011-10-07 11:36:40 +00:00
|
|
|
int is_64bit = 0;
|
perf/x86: Optimize intel_pmu_pebs_fixup_ip()
There's been reports of high NMI handler overhead, highlighted by
such kernel messages:
[ 3697.380195] perf samples too long (10009 > 10000), lowering kernel.perf_event_max_sample_rate to 13000
[ 3697.389509] INFO: NMI handler (perf_event_nmi_handler) took too long to run: 9.331 msecs
Don Zickus analyzed the source of the overhead and reported:
> While there are a few places that are causing latencies, for now I focused on
> the longest one first. It seems to be 'copy_user_from_nmi'
>
> intel_pmu_handle_irq ->
> intel_pmu_drain_pebs_nhm ->
> __intel_pmu_drain_pebs_nhm ->
> __intel_pmu_pebs_event ->
> intel_pmu_pebs_fixup_ip ->
> copy_from_user_nmi
>
> In intel_pmu_pebs_fixup_ip(), if the while-loop goes over 50, the sum of
> all the copy_from_user_nmi latencies seems to go over 1,000,000 cycles
> (there are some cases where only 10 iterations are needed to go that high
> too, but in generall over 50 or so). At this point copy_user_from_nmi
> seems to account for over 90% of the nmi latency.
The solution to that is to avoid having to call copy_from_user_nmi() for
every instruction.
Since we already limit the max basic block size, we can easily
pre-allocate a piece of memory to copy the entire thing into in one
go.
Don reported this test result:
> Your patch made a huge difference in improvement. The
> copy_from_user_nmi() no longer hits the million of cycles. I still
> have a batch of 100,000-300,000 cycles. My longest NMI paths used
> to be dominated by copy_from_user_nmi, now it is not (I have to dig
> up the new hot path).
Reported-and-tested-by: Don Zickus <dzickus@redhat.com>
Cc: jmario@redhat.com
Cc: acme@infradead.org
Cc: dave.hansen@linux.intel.com
Cc: eranian@google.com
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20131016105755.GX10651@twins.programming.kicks-ass.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-10-15 10:14:04 +00:00
|
|
|
void *kaddr;
|
2010-03-03 12:12:23 +00:00
|
|
|
|
2010-03-03 16:07:40 +00:00
|
|
|
/*
|
|
|
|
* We don't need to fixup if the PEBS assist is fault like
|
|
|
|
*/
|
|
|
|
if (!x86_pmu.intel_cap.pebs_trap)
|
|
|
|
return 1;
|
|
|
|
|
2010-03-05 15:29:14 +00:00
|
|
|
/*
|
|
|
|
* No LBR entry, no basic block, no rewinding
|
|
|
|
*/
|
2010-03-03 12:12:23 +00:00
|
|
|
if (!cpuc->lbr_stack.nr || !from || !to)
|
|
|
|
return 0;
|
|
|
|
|
2010-03-05 15:29:14 +00:00
|
|
|
/*
|
|
|
|
* Basic blocks should never cross user/kernel boundaries
|
|
|
|
*/
|
|
|
|
if (kernel_ip(ip) != kernel_ip(to))
|
|
|
|
return 0;
|
|
|
|
|
|
|
|
/*
|
|
|
|
* unsigned math, either ip is before the start (impossible) or
|
|
|
|
* the basic block is larger than 1 page (sanity)
|
|
|
|
*/
|
perf/x86: Optimize intel_pmu_pebs_fixup_ip()
There's been reports of high NMI handler overhead, highlighted by
such kernel messages:
[ 3697.380195] perf samples too long (10009 > 10000), lowering kernel.perf_event_max_sample_rate to 13000
[ 3697.389509] INFO: NMI handler (perf_event_nmi_handler) took too long to run: 9.331 msecs
Don Zickus analyzed the source of the overhead and reported:
> While there are a few places that are causing latencies, for now I focused on
> the longest one first. It seems to be 'copy_user_from_nmi'
>
> intel_pmu_handle_irq ->
> intel_pmu_drain_pebs_nhm ->
> __intel_pmu_drain_pebs_nhm ->
> __intel_pmu_pebs_event ->
> intel_pmu_pebs_fixup_ip ->
> copy_from_user_nmi
>
> In intel_pmu_pebs_fixup_ip(), if the while-loop goes over 50, the sum of
> all the copy_from_user_nmi latencies seems to go over 1,000,000 cycles
> (there are some cases where only 10 iterations are needed to go that high
> too, but in generall over 50 or so). At this point copy_user_from_nmi
> seems to account for over 90% of the nmi latency.
The solution to that is to avoid having to call copy_from_user_nmi() for
every instruction.
Since we already limit the max basic block size, we can easily
pre-allocate a piece of memory to copy the entire thing into in one
go.
Don reported this test result:
> Your patch made a huge difference in improvement. The
> copy_from_user_nmi() no longer hits the million of cycles. I still
> have a batch of 100,000-300,000 cycles. My longest NMI paths used
> to be dominated by copy_from_user_nmi, now it is not (I have to dig
> up the new hot path).
Reported-and-tested-by: Don Zickus <dzickus@redhat.com>
Cc: jmario@redhat.com
Cc: acme@infradead.org
Cc: dave.hansen@linux.intel.com
Cc: eranian@google.com
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20131016105755.GX10651@twins.programming.kicks-ass.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-10-15 10:14:04 +00:00
|
|
|
if ((ip - to) > PEBS_FIXUP_SIZE)
|
2010-03-03 12:12:23 +00:00
|
|
|
return 0;
|
|
|
|
|
|
|
|
/*
|
|
|
|
* We sampled a branch insn, rewind using the LBR stack
|
|
|
|
*/
|
|
|
|
if (ip == to) {
|
2012-07-10 07:42:15 +00:00
|
|
|
set_linear_ip(regs, from);
|
2010-03-03 12:12:23 +00:00
|
|
|
return 1;
|
|
|
|
}
|
|
|
|
|
perf/x86: Optimize intel_pmu_pebs_fixup_ip()
There's been reports of high NMI handler overhead, highlighted by
such kernel messages:
[ 3697.380195] perf samples too long (10009 > 10000), lowering kernel.perf_event_max_sample_rate to 13000
[ 3697.389509] INFO: NMI handler (perf_event_nmi_handler) took too long to run: 9.331 msecs
Don Zickus analyzed the source of the overhead and reported:
> While there are a few places that are causing latencies, for now I focused on
> the longest one first. It seems to be 'copy_user_from_nmi'
>
> intel_pmu_handle_irq ->
> intel_pmu_drain_pebs_nhm ->
> __intel_pmu_drain_pebs_nhm ->
> __intel_pmu_pebs_event ->
> intel_pmu_pebs_fixup_ip ->
> copy_from_user_nmi
>
> In intel_pmu_pebs_fixup_ip(), if the while-loop goes over 50, the sum of
> all the copy_from_user_nmi latencies seems to go over 1,000,000 cycles
> (there are some cases where only 10 iterations are needed to go that high
> too, but in generall over 50 or so). At this point copy_user_from_nmi
> seems to account for over 90% of the nmi latency.
The solution to that is to avoid having to call copy_from_user_nmi() for
every instruction.
Since we already limit the max basic block size, we can easily
pre-allocate a piece of memory to copy the entire thing into in one
go.
Don reported this test result:
> Your patch made a huge difference in improvement. The
> copy_from_user_nmi() no longer hits the million of cycles. I still
> have a batch of 100,000-300,000 cycles. My longest NMI paths used
> to be dominated by copy_from_user_nmi, now it is not (I have to dig
> up the new hot path).
Reported-and-tested-by: Don Zickus <dzickus@redhat.com>
Cc: jmario@redhat.com
Cc: acme@infradead.org
Cc: dave.hansen@linux.intel.com
Cc: eranian@google.com
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20131016105755.GX10651@twins.programming.kicks-ass.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-10-15 10:14:04 +00:00
|
|
|
if (!kernel_ip(ip)) {
|
|
|
|
int size, bytes;
|
|
|
|
u8 *buf = this_cpu_read(insn_buffer);
|
|
|
|
|
|
|
|
size = ip - to; /* Must fit our buffer, see above */
|
|
|
|
bytes = copy_from_user_nmi(buf, (void __user *)to, size);
|
2013-10-30 20:16:22 +00:00
|
|
|
if (bytes != 0)
|
perf/x86: Optimize intel_pmu_pebs_fixup_ip()
There's been reports of high NMI handler overhead, highlighted by
such kernel messages:
[ 3697.380195] perf samples too long (10009 > 10000), lowering kernel.perf_event_max_sample_rate to 13000
[ 3697.389509] INFO: NMI handler (perf_event_nmi_handler) took too long to run: 9.331 msecs
Don Zickus analyzed the source of the overhead and reported:
> While there are a few places that are causing latencies, for now I focused on
> the longest one first. It seems to be 'copy_user_from_nmi'
>
> intel_pmu_handle_irq ->
> intel_pmu_drain_pebs_nhm ->
> __intel_pmu_drain_pebs_nhm ->
> __intel_pmu_pebs_event ->
> intel_pmu_pebs_fixup_ip ->
> copy_from_user_nmi
>
> In intel_pmu_pebs_fixup_ip(), if the while-loop goes over 50, the sum of
> all the copy_from_user_nmi latencies seems to go over 1,000,000 cycles
> (there are some cases where only 10 iterations are needed to go that high
> too, but in generall over 50 or so). At this point copy_user_from_nmi
> seems to account for over 90% of the nmi latency.
The solution to that is to avoid having to call copy_from_user_nmi() for
every instruction.
Since we already limit the max basic block size, we can easily
pre-allocate a piece of memory to copy the entire thing into in one
go.
Don reported this test result:
> Your patch made a huge difference in improvement. The
> copy_from_user_nmi() no longer hits the million of cycles. I still
> have a batch of 100,000-300,000 cycles. My longest NMI paths used
> to be dominated by copy_from_user_nmi, now it is not (I have to dig
> up the new hot path).
Reported-and-tested-by: Don Zickus <dzickus@redhat.com>
Cc: jmario@redhat.com
Cc: acme@infradead.org
Cc: dave.hansen@linux.intel.com
Cc: eranian@google.com
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20131016105755.GX10651@twins.programming.kicks-ass.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-10-15 10:14:04 +00:00
|
|
|
return 0;
|
|
|
|
|
|
|
|
kaddr = buf;
|
|
|
|
} else {
|
|
|
|
kaddr = (void *)to;
|
|
|
|
}
|
|
|
|
|
2010-03-03 12:12:23 +00:00
|
|
|
do {
|
|
|
|
struct insn insn;
|
|
|
|
|
|
|
|
old_to = to;
|
|
|
|
|
2011-10-07 11:36:40 +00:00
|
|
|
#ifdef CONFIG_X86_64
|
|
|
|
is_64bit = kernel_ip(to) || !test_thread_flag(TIF_IA32);
|
|
|
|
#endif
|
|
|
|
insn_init(&insn, kaddr, is_64bit);
|
2010-03-03 12:12:23 +00:00
|
|
|
insn_get_length(&insn);
|
perf/x86: Optimize intel_pmu_pebs_fixup_ip()
There's been reports of high NMI handler overhead, highlighted by
such kernel messages:
[ 3697.380195] perf samples too long (10009 > 10000), lowering kernel.perf_event_max_sample_rate to 13000
[ 3697.389509] INFO: NMI handler (perf_event_nmi_handler) took too long to run: 9.331 msecs
Don Zickus analyzed the source of the overhead and reported:
> While there are a few places that are causing latencies, for now I focused on
> the longest one first. It seems to be 'copy_user_from_nmi'
>
> intel_pmu_handle_irq ->
> intel_pmu_drain_pebs_nhm ->
> __intel_pmu_drain_pebs_nhm ->
> __intel_pmu_pebs_event ->
> intel_pmu_pebs_fixup_ip ->
> copy_from_user_nmi
>
> In intel_pmu_pebs_fixup_ip(), if the while-loop goes over 50, the sum of
> all the copy_from_user_nmi latencies seems to go over 1,000,000 cycles
> (there are some cases where only 10 iterations are needed to go that high
> too, but in generall over 50 or so). At this point copy_user_from_nmi
> seems to account for over 90% of the nmi latency.
The solution to that is to avoid having to call copy_from_user_nmi() for
every instruction.
Since we already limit the max basic block size, we can easily
pre-allocate a piece of memory to copy the entire thing into in one
go.
Don reported this test result:
> Your patch made a huge difference in improvement. The
> copy_from_user_nmi() no longer hits the million of cycles. I still
> have a batch of 100,000-300,000 cycles. My longest NMI paths used
> to be dominated by copy_from_user_nmi, now it is not (I have to dig
> up the new hot path).
Reported-and-tested-by: Don Zickus <dzickus@redhat.com>
Cc: jmario@redhat.com
Cc: acme@infradead.org
Cc: dave.hansen@linux.intel.com
Cc: eranian@google.com
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20131016105755.GX10651@twins.programming.kicks-ass.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-10-15 10:14:04 +00:00
|
|
|
|
2010-03-03 12:12:23 +00:00
|
|
|
to += insn.length;
|
perf/x86: Optimize intel_pmu_pebs_fixup_ip()
There's been reports of high NMI handler overhead, highlighted by
such kernel messages:
[ 3697.380195] perf samples too long (10009 > 10000), lowering kernel.perf_event_max_sample_rate to 13000
[ 3697.389509] INFO: NMI handler (perf_event_nmi_handler) took too long to run: 9.331 msecs
Don Zickus analyzed the source of the overhead and reported:
> While there are a few places that are causing latencies, for now I focused on
> the longest one first. It seems to be 'copy_user_from_nmi'
>
> intel_pmu_handle_irq ->
> intel_pmu_drain_pebs_nhm ->
> __intel_pmu_drain_pebs_nhm ->
> __intel_pmu_pebs_event ->
> intel_pmu_pebs_fixup_ip ->
> copy_from_user_nmi
>
> In intel_pmu_pebs_fixup_ip(), if the while-loop goes over 50, the sum of
> all the copy_from_user_nmi latencies seems to go over 1,000,000 cycles
> (there are some cases where only 10 iterations are needed to go that high
> too, but in generall over 50 or so). At this point copy_user_from_nmi
> seems to account for over 90% of the nmi latency.
The solution to that is to avoid having to call copy_from_user_nmi() for
every instruction.
Since we already limit the max basic block size, we can easily
pre-allocate a piece of memory to copy the entire thing into in one
go.
Don reported this test result:
> Your patch made a huge difference in improvement. The
> copy_from_user_nmi() no longer hits the million of cycles. I still
> have a batch of 100,000-300,000 cycles. My longest NMI paths used
> to be dominated by copy_from_user_nmi, now it is not (I have to dig
> up the new hot path).
Reported-and-tested-by: Don Zickus <dzickus@redhat.com>
Cc: jmario@redhat.com
Cc: acme@infradead.org
Cc: dave.hansen@linux.intel.com
Cc: eranian@google.com
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20131016105755.GX10651@twins.programming.kicks-ass.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-10-15 10:14:04 +00:00
|
|
|
kaddr += insn.length;
|
2010-03-03 12:12:23 +00:00
|
|
|
} while (to < ip);
|
|
|
|
|
|
|
|
if (to == ip) {
|
2012-07-10 07:42:15 +00:00
|
|
|
set_linear_ip(regs, old_to);
|
2010-03-03 12:12:23 +00:00
|
|
|
return 1;
|
|
|
|
}
|
|
|
|
|
2010-03-05 15:29:14 +00:00
|
|
|
/*
|
|
|
|
* Even though we decoded the basic block, the instruction stream
|
|
|
|
* never matched the given IP, either the TO or the IP got corrupted.
|
|
|
|
*/
|
2010-03-03 12:12:23 +00:00
|
|
|
return 0;
|
|
|
|
}
|
|
|
|
|
2013-09-06 03:37:39 +00:00
|
|
|
static inline u64 intel_hsw_weight(struct pebs_record_hsw *pebs)
|
|
|
|
{
|
|
|
|
if (pebs->tsx_tuning) {
|
|
|
|
union hsw_tsx_tuning tsx = { .value = pebs->tsx_tuning };
|
|
|
|
return tsx.cycles_last_block;
|
|
|
|
}
|
|
|
|
return 0;
|
|
|
|
}
|
|
|
|
|
2013-09-20 14:40:40 +00:00
|
|
|
static inline u64 intel_hsw_transaction(struct pebs_record_hsw *pebs)
|
|
|
|
{
|
|
|
|
u64 txn = (pebs->tsx_tuning & PEBS_HSW_TSX_FLAGS) >> 32;
|
|
|
|
|
|
|
|
/* For RTM XABORTs also log the abort code from AX */
|
|
|
|
if ((txn & PERF_TXN_TRANSACTION) && (pebs->ax & 1))
|
|
|
|
txn |= ((pebs->ax >> 24) & 0xff) << PERF_TXN_ABORT_SHIFT;
|
|
|
|
return txn;
|
|
|
|
}
|
|
|
|
|
2010-04-08 21:03:20 +00:00
|
|
|
static void __intel_pmu_pebs_event(struct perf_event *event,
|
|
|
|
struct pt_regs *iregs, void *__pebs)
|
|
|
|
{
|
2014-08-11 19:27:13 +00:00
|
|
|
#define PERF_X86_EVENT_PEBS_HSW_PREC \
|
|
|
|
(PERF_X86_EVENT_PEBS_ST_HSW | \
|
|
|
|
PERF_X86_EVENT_PEBS_LD_HSW | \
|
|
|
|
PERF_X86_EVENT_PEBS_NA_HSW)
|
2010-04-08 21:03:20 +00:00
|
|
|
/*
|
2013-09-12 11:00:47 +00:00
|
|
|
* We cast to the biggest pebs_record but are careful not to
|
|
|
|
* unconditionally access the 'extra' entries.
|
2010-04-08 21:03:20 +00:00
|
|
|
*/
|
2012-02-09 22:20:57 +00:00
|
|
|
struct cpu_hw_events *cpuc = &__get_cpu_var(cpu_hw_events);
|
2013-09-06 03:37:39 +00:00
|
|
|
struct pebs_record_hsw *pebs = __pebs;
|
2010-04-08 21:03:20 +00:00
|
|
|
struct perf_sample_data data;
|
|
|
|
struct pt_regs regs;
|
2013-01-24 15:10:32 +00:00
|
|
|
u64 sample_type;
|
2014-08-11 19:27:13 +00:00
|
|
|
int fll, fst, dsrc;
|
|
|
|
int fl = event->hw.flags;
|
2010-04-08 21:03:20 +00:00
|
|
|
|
|
|
|
if (!intel_pmu_save_and_restart(event))
|
|
|
|
return;
|
|
|
|
|
2014-08-11 19:27:13 +00:00
|
|
|
sample_type = event->attr.sample_type;
|
|
|
|
dsrc = sample_type & PERF_SAMPLE_DATA_SRC;
|
|
|
|
|
|
|
|
fll = fl & PERF_X86_EVENT_PEBS_LDLAT;
|
|
|
|
fst = fl & (PERF_X86_EVENT_PEBS_ST | PERF_X86_EVENT_PEBS_HSW_PREC);
|
2013-01-24 15:10:32 +00:00
|
|
|
|
2012-04-02 18:19:08 +00:00
|
|
|
perf_sample_data_init(&data, 0, event->hw.last_period);
|
2010-04-08 21:03:20 +00:00
|
|
|
|
2013-01-24 15:10:32 +00:00
|
|
|
data.period = event->hw.last_period;
|
|
|
|
|
|
|
|
/*
|
2014-08-11 19:27:13 +00:00
|
|
|
* Use latency for weight (only avail with PEBS-LL)
|
2013-01-24 15:10:32 +00:00
|
|
|
*/
|
2014-08-11 19:27:13 +00:00
|
|
|
if (fll && (sample_type & PERF_SAMPLE_WEIGHT))
|
|
|
|
data.weight = pebs->lat;
|
|
|
|
|
|
|
|
/*
|
|
|
|
* data.data_src encodes the data source
|
|
|
|
*/
|
|
|
|
if (dsrc) {
|
|
|
|
u64 val = PERF_MEM_NA;
|
|
|
|
if (fll)
|
|
|
|
val = load_latency_data(pebs->dse);
|
|
|
|
else if (fst && (fl & PERF_X86_EVENT_PEBS_HSW_PREC))
|
|
|
|
val = precise_datala_hsw(event, pebs->dse);
|
|
|
|
else if (fst)
|
|
|
|
val = precise_store_data(pebs->dse);
|
|
|
|
data.data_src.val = val;
|
2013-01-24 15:10:32 +00:00
|
|
|
}
|
|
|
|
|
2010-04-08 21:03:20 +00:00
|
|
|
/*
|
|
|
|
* We use the interrupt regs as a base because the PEBS record
|
|
|
|
* does not contain a full regs set, specifically it seems to
|
|
|
|
* lack segment descriptors, which get used by things like
|
|
|
|
* user_mode().
|
|
|
|
*
|
|
|
|
* In the simple case fix up only the IP and BP,SP regs, for
|
|
|
|
* PERF_SAMPLE_IP and PERF_SAMPLE_CALLCHAIN to function properly.
|
|
|
|
* A possible PERF_SAMPLE_REGS will have to transfer all regs.
|
|
|
|
*/
|
|
|
|
regs = *iregs;
|
2012-07-10 07:42:15 +00:00
|
|
|
regs.flags = pebs->flags;
|
|
|
|
set_linear_ip(®s, pebs->ip);
|
2010-04-08 21:03:20 +00:00
|
|
|
regs.bp = pebs->bp;
|
|
|
|
regs.sp = pebs->sp;
|
|
|
|
|
2013-06-18 00:36:47 +00:00
|
|
|
if (event->attr.precise_ip > 1 && x86_pmu.intel_cap.pebs_format >= 2) {
|
2013-09-06 03:37:39 +00:00
|
|
|
regs.ip = pebs->real_ip;
|
2013-06-18 00:36:47 +00:00
|
|
|
regs.flags |= PERF_EFLAGS_EXACT;
|
|
|
|
} else if (event->attr.precise_ip > 1 && intel_pmu_pebs_fixup_ip(®s))
|
2010-04-08 21:03:20 +00:00
|
|
|
regs.flags |= PERF_EFLAGS_EXACT;
|
|
|
|
else
|
|
|
|
regs.flags &= ~PERF_EFLAGS_EXACT;
|
|
|
|
|
2014-08-11 19:27:13 +00:00
|
|
|
if ((sample_type & PERF_SAMPLE_ADDR) &&
|
2013-09-12 11:00:47 +00:00
|
|
|
x86_pmu.intel_cap.pebs_format >= 1)
|
2013-06-18 00:36:52 +00:00
|
|
|
data.addr = pebs->dla;
|
|
|
|
|
2013-09-20 14:40:40 +00:00
|
|
|
if (x86_pmu.intel_cap.pebs_format >= 2) {
|
|
|
|
/* Only set the TSX weight when no memory weight. */
|
2014-08-11 19:27:13 +00:00
|
|
|
if ((sample_type & PERF_SAMPLE_WEIGHT) && !fll)
|
2013-09-20 14:40:40 +00:00
|
|
|
data.weight = intel_hsw_weight(pebs);
|
|
|
|
|
2014-08-11 19:27:13 +00:00
|
|
|
if (sample_type & PERF_SAMPLE_TRANSACTION)
|
2013-09-20 14:40:40 +00:00
|
|
|
data.txn = intel_hsw_transaction(pebs);
|
|
|
|
}
|
2013-09-06 03:37:39 +00:00
|
|
|
|
2012-02-09 22:20:57 +00:00
|
|
|
if (has_branch_stack(event))
|
|
|
|
data.br_stack = &cpuc->lbr_stack;
|
|
|
|
|
2011-06-27 12:41:57 +00:00
|
|
|
if (perf_event_overflow(event, &data, ®s))
|
perf: Rework the PMU methods
Replace pmu::{enable,disable,start,stop,unthrottle} with
pmu::{add,del,start,stop}, all of which take a flags argument.
The new interface extends the capability to stop a counter while
keeping it scheduled on the PMU. We replace the throttled state with
the generic stopped state.
This also allows us to efficiently stop/start counters over certain
code paths (like IRQ handlers).
It also allows scheduling a counter without it starting, allowing for
a generic frozen state (useful for rotating stopped counters).
The stopped state is implemented in two different ways, depending on
how the architecture implemented the throttled state:
1) We disable the counter:
a) the pmu has per-counter enable bits, we flip that
b) we program a NOP event, preserving the counter state
2) We store the counter state and ignore all read/overflow events
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: paulus <paulus@samba.org>
Cc: stephane eranian <eranian@googlemail.com>
Cc: Robert Richter <robert.richter@amd.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Cyrill Gorcunov <gorcunov@gmail.com>
Cc: Lin Ming <ming.m.lin@intel.com>
Cc: Yanmin <yanmin_zhang@linux.intel.com>
Cc: Deng-Cheng Zhu <dengcheng.zhu@gmail.com>
Cc: David Miller <davem@davemloft.net>
Cc: Michael Cree <mcree@orcon.net.nz>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-06-16 12:37:10 +00:00
|
|
|
x86_pmu_stop(event, 0);
|
2010-04-08 21:03:20 +00:00
|
|
|
}
|
|
|
|
|
perf, x86: Add PEBS infrastructure
This patch implements support for Intel Precise Event Based Sampling,
which is an alternative counter mode in which the counter triggers a
hardware assist to collect information on events. The hardware assist
takes a trap like snapshot of a subset of the machine registers.
This data is written to the Intel Debug-Store, which can be programmed
with a data threshold at which to raise a PMI.
With the PEBS hardware assist being trap like, the reported IP is always
one instruction after the actual instruction that triggered the event.
This implements a simple PEBS model that always takes a single PEBS event
at a time. This is done so that the interaction with the rest of the
system is as expected (freq adjust, period randomization, lbr,
callchains, etc.).
It adds an ABI element: perf_event_attr::precise, which indicates that we
wish to use this (constrained, but precise) mode.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arnaldo Carvalho de Melo <acme@infradead.org>
Cc: paulus@samba.org
Cc: eranian@google.com
Cc: robert.richter@amd.com
Cc: fweisbec@gmail.com
LKML-Reference: <20100304140100.392111285@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-03-02 18:52:12 +00:00
|
|
|
static void intel_pmu_drain_pebs_core(struct pt_regs *iregs)
|
|
|
|
{
|
|
|
|
struct cpu_hw_events *cpuc = &__get_cpu_var(cpu_hw_events);
|
|
|
|
struct debug_store *ds = cpuc->ds;
|
|
|
|
struct perf_event *event = cpuc->events[0]; /* PMC0 only */
|
|
|
|
struct pebs_record_core *at, *top;
|
|
|
|
int n;
|
|
|
|
|
2010-10-19 12:22:50 +00:00
|
|
|
if (!x86_pmu.pebs_active)
|
perf, x86: Add PEBS infrastructure
This patch implements support for Intel Precise Event Based Sampling,
which is an alternative counter mode in which the counter triggers a
hardware assist to collect information on events. The hardware assist
takes a trap like snapshot of a subset of the machine registers.
This data is written to the Intel Debug-Store, which can be programmed
with a data threshold at which to raise a PMI.
With the PEBS hardware assist being trap like, the reported IP is always
one instruction after the actual instruction that triggered the event.
This implements a simple PEBS model that always takes a single PEBS event
at a time. This is done so that the interaction with the rest of the
system is as expected (freq adjust, period randomization, lbr,
callchains, etc.).
It adds an ABI element: perf_event_attr::precise, which indicates that we
wish to use this (constrained, but precise) mode.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arnaldo Carvalho de Melo <acme@infradead.org>
Cc: paulus@samba.org
Cc: eranian@google.com
Cc: robert.richter@amd.com
Cc: fweisbec@gmail.com
LKML-Reference: <20100304140100.392111285@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-03-02 18:52:12 +00:00
|
|
|
return;
|
|
|
|
|
|
|
|
at = (struct pebs_record_core *)(unsigned long)ds->pebs_buffer_base;
|
|
|
|
top = (struct pebs_record_core *)(unsigned long)ds->pebs_index;
|
|
|
|
|
2010-03-09 10:41:02 +00:00
|
|
|
/*
|
|
|
|
* Whatever else happens, drain the thing
|
|
|
|
*/
|
|
|
|
ds->pebs_index = ds->pebs_buffer_base;
|
|
|
|
|
|
|
|
if (!test_bit(0, cpuc->active_mask))
|
2010-03-06 12:26:11 +00:00
|
|
|
return;
|
perf, x86: Add PEBS infrastructure
This patch implements support for Intel Precise Event Based Sampling,
which is an alternative counter mode in which the counter triggers a
hardware assist to collect information on events. The hardware assist
takes a trap like snapshot of a subset of the machine registers.
This data is written to the Intel Debug-Store, which can be programmed
with a data threshold at which to raise a PMI.
With the PEBS hardware assist being trap like, the reported IP is always
one instruction after the actual instruction that triggered the event.
This implements a simple PEBS model that always takes a single PEBS event
at a time. This is done so that the interaction with the rest of the
system is as expected (freq adjust, period randomization, lbr,
callchains, etc.).
It adds an ABI element: perf_event_attr::precise, which indicates that we
wish to use this (constrained, but precise) mode.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arnaldo Carvalho de Melo <acme@infradead.org>
Cc: paulus@samba.org
Cc: eranian@google.com
Cc: robert.richter@amd.com
Cc: fweisbec@gmail.com
LKML-Reference: <20100304140100.392111285@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-03-02 18:52:12 +00:00
|
|
|
|
2010-03-09 10:41:02 +00:00
|
|
|
WARN_ON_ONCE(!event);
|
|
|
|
|
2010-04-08 21:03:20 +00:00
|
|
|
if (!event->attr.precise_ip)
|
2010-03-09 10:41:02 +00:00
|
|
|
return;
|
|
|
|
|
|
|
|
n = top - at;
|
|
|
|
if (n <= 0)
|
|
|
|
return;
|
perf, x86: Add PEBS infrastructure
This patch implements support for Intel Precise Event Based Sampling,
which is an alternative counter mode in which the counter triggers a
hardware assist to collect information on events. The hardware assist
takes a trap like snapshot of a subset of the machine registers.
This data is written to the Intel Debug-Store, which can be programmed
with a data threshold at which to raise a PMI.
With the PEBS hardware assist being trap like, the reported IP is always
one instruction after the actual instruction that triggered the event.
This implements a simple PEBS model that always takes a single PEBS event
at a time. This is done so that the interaction with the rest of the
system is as expected (freq adjust, period randomization, lbr,
callchains, etc.).
It adds an ABI element: perf_event_attr::precise, which indicates that we
wish to use this (constrained, but precise) mode.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arnaldo Carvalho de Melo <acme@infradead.org>
Cc: paulus@samba.org
Cc: eranian@google.com
Cc: robert.richter@amd.com
Cc: fweisbec@gmail.com
LKML-Reference: <20100304140100.392111285@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-03-02 18:52:12 +00:00
|
|
|
|
2010-03-09 10:41:02 +00:00
|
|
|
/*
|
|
|
|
* Should not happen, we program the threshold at 1 and do not
|
|
|
|
* set a reset value.
|
|
|
|
*/
|
2012-06-06 00:56:48 +00:00
|
|
|
WARN_ONCE(n > 1, "bad leftover pebs %d\n", n);
|
2010-03-09 10:41:02 +00:00
|
|
|
at += n - 1;
|
|
|
|
|
2010-04-08 21:03:20 +00:00
|
|
|
__intel_pmu_pebs_event(event, iregs, at);
|
perf, x86: Add PEBS infrastructure
This patch implements support for Intel Precise Event Based Sampling,
which is an alternative counter mode in which the counter triggers a
hardware assist to collect information on events. The hardware assist
takes a trap like snapshot of a subset of the machine registers.
This data is written to the Intel Debug-Store, which can be programmed
with a data threshold at which to raise a PMI.
With the PEBS hardware assist being trap like, the reported IP is always
one instruction after the actual instruction that triggered the event.
This implements a simple PEBS model that always takes a single PEBS event
at a time. This is done so that the interaction with the rest of the
system is as expected (freq adjust, period randomization, lbr,
callchains, etc.).
It adds an ABI element: perf_event_attr::precise, which indicates that we
wish to use this (constrained, but precise) mode.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arnaldo Carvalho de Melo <acme@infradead.org>
Cc: paulus@samba.org
Cc: eranian@google.com
Cc: robert.richter@amd.com
Cc: fweisbec@gmail.com
LKML-Reference: <20100304140100.392111285@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-03-02 18:52:12 +00:00
|
|
|
}
|
|
|
|
|
2013-09-12 11:00:47 +00:00
|
|
|
static void intel_pmu_drain_pebs_nhm(struct pt_regs *iregs)
|
perf, x86: Add PEBS infrastructure
This patch implements support for Intel Precise Event Based Sampling,
which is an alternative counter mode in which the counter triggers a
hardware assist to collect information on events. The hardware assist
takes a trap like snapshot of a subset of the machine registers.
This data is written to the Intel Debug-Store, which can be programmed
with a data threshold at which to raise a PMI.
With the PEBS hardware assist being trap like, the reported IP is always
one instruction after the actual instruction that triggered the event.
This implements a simple PEBS model that always takes a single PEBS event
at a time. This is done so that the interaction with the rest of the
system is as expected (freq adjust, period randomization, lbr,
callchains, etc.).
It adds an ABI element: perf_event_attr::precise, which indicates that we
wish to use this (constrained, but precise) mode.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arnaldo Carvalho de Melo <acme@infradead.org>
Cc: paulus@samba.org
Cc: eranian@google.com
Cc: robert.richter@amd.com
Cc: fweisbec@gmail.com
LKML-Reference: <20100304140100.392111285@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-03-02 18:52:12 +00:00
|
|
|
{
|
|
|
|
struct cpu_hw_events *cpuc = &__get_cpu_var(cpu_hw_events);
|
|
|
|
struct debug_store *ds = cpuc->ds;
|
|
|
|
struct perf_event *event = NULL;
|
2013-09-12 11:00:47 +00:00
|
|
|
void *at, *top;
|
2010-03-06 17:57:38 +00:00
|
|
|
u64 status = 0;
|
2013-09-16 07:23:02 +00:00
|
|
|
int bit;
|
2013-09-12 11:00:47 +00:00
|
|
|
|
|
|
|
if (!x86_pmu.pebs_active)
|
|
|
|
return;
|
|
|
|
|
|
|
|
at = (struct pebs_record_nhm *)(unsigned long)ds->pebs_buffer_base;
|
|
|
|
top = (struct pebs_record_nhm *)(unsigned long)ds->pebs_index;
|
perf, x86: Add PEBS infrastructure
This patch implements support for Intel Precise Event Based Sampling,
which is an alternative counter mode in which the counter triggers a
hardware assist to collect information on events. The hardware assist
takes a trap like snapshot of a subset of the machine registers.
This data is written to the Intel Debug-Store, which can be programmed
with a data threshold at which to raise a PMI.
With the PEBS hardware assist being trap like, the reported IP is always
one instruction after the actual instruction that triggered the event.
This implements a simple PEBS model that always takes a single PEBS event
at a time. This is done so that the interaction with the rest of the
system is as expected (freq adjust, period randomization, lbr,
callchains, etc.).
It adds an ABI element: perf_event_attr::precise, which indicates that we
wish to use this (constrained, but precise) mode.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arnaldo Carvalho de Melo <acme@infradead.org>
Cc: paulus@samba.org
Cc: eranian@google.com
Cc: robert.richter@amd.com
Cc: fweisbec@gmail.com
LKML-Reference: <20100304140100.392111285@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-03-02 18:52:12 +00:00
|
|
|
|
|
|
|
ds->pebs_index = ds->pebs_buffer_base;
|
|
|
|
|
2013-09-16 07:23:02 +00:00
|
|
|
if (unlikely(at > top))
|
2013-09-12 11:00:47 +00:00
|
|
|
return;
|
|
|
|
|
|
|
|
/*
|
|
|
|
* Should not happen, we program the threshold at 1 and do not
|
|
|
|
* set a reset value.
|
|
|
|
*/
|
2013-09-16 07:23:02 +00:00
|
|
|
WARN_ONCE(top - at > x86_pmu.max_pebs_events * x86_pmu.pebs_record_size,
|
|
|
|
"Unexpected number of pebs records %ld\n",
|
2013-09-20 11:08:50 +00:00
|
|
|
(long)(top - at) / x86_pmu.pebs_record_size);
|
2013-09-12 11:00:47 +00:00
|
|
|
|
2013-06-18 00:36:47 +00:00
|
|
|
for (; at < top; at += x86_pmu.pebs_record_size) {
|
|
|
|
struct pebs_record_nhm *p = at;
|
perf, x86: Add PEBS infrastructure
This patch implements support for Intel Precise Event Based Sampling,
which is an alternative counter mode in which the counter triggers a
hardware assist to collect information on events. The hardware assist
takes a trap like snapshot of a subset of the machine registers.
This data is written to the Intel Debug-Store, which can be programmed
with a data threshold at which to raise a PMI.
With the PEBS hardware assist being trap like, the reported IP is always
one instruction after the actual instruction that triggered the event.
This implements a simple PEBS model that always takes a single PEBS event
at a time. This is done so that the interaction with the rest of the
system is as expected (freq adjust, period randomization, lbr,
callchains, etc.).
It adds an ABI element: perf_event_attr::precise, which indicates that we
wish to use this (constrained, but precise) mode.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arnaldo Carvalho de Melo <acme@infradead.org>
Cc: paulus@samba.org
Cc: eranian@google.com
Cc: robert.richter@amd.com
Cc: fweisbec@gmail.com
LKML-Reference: <20100304140100.392111285@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-03-02 18:52:12 +00:00
|
|
|
|
2013-06-18 00:36:47 +00:00
|
|
|
for_each_set_bit(bit, (unsigned long *)&p->status,
|
|
|
|
x86_pmu.max_pebs_events) {
|
2010-03-06 17:57:38 +00:00
|
|
|
event = cpuc->events[bit];
|
|
|
|
if (!test_bit(bit, cpuc->active_mask))
|
perf, x86: Add PEBS infrastructure
This patch implements support for Intel Precise Event Based Sampling,
which is an alternative counter mode in which the counter triggers a
hardware assist to collect information on events. The hardware assist
takes a trap like snapshot of a subset of the machine registers.
This data is written to the Intel Debug-Store, which can be programmed
with a data threshold at which to raise a PMI.
With the PEBS hardware assist being trap like, the reported IP is always
one instruction after the actual instruction that triggered the event.
This implements a simple PEBS model that always takes a single PEBS event
at a time. This is done so that the interaction with the rest of the
system is as expected (freq adjust, period randomization, lbr,
callchains, etc.).
It adds an ABI element: perf_event_attr::precise, which indicates that we
wish to use this (constrained, but precise) mode.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arnaldo Carvalho de Melo <acme@infradead.org>
Cc: paulus@samba.org
Cc: eranian@google.com
Cc: robert.richter@amd.com
Cc: fweisbec@gmail.com
LKML-Reference: <20100304140100.392111285@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-03-02 18:52:12 +00:00
|
|
|
continue;
|
|
|
|
|
2010-03-06 17:57:38 +00:00
|
|
|
WARN_ON_ONCE(!event);
|
|
|
|
|
2010-04-08 21:03:20 +00:00
|
|
|
if (!event->attr.precise_ip)
|
2010-03-06 17:57:38 +00:00
|
|
|
continue;
|
|
|
|
|
|
|
|
if (__test_and_set_bit(bit, (unsigned long *)&status))
|
|
|
|
continue;
|
|
|
|
|
|
|
|
break;
|
perf, x86: Add PEBS infrastructure
This patch implements support for Intel Precise Event Based Sampling,
which is an alternative counter mode in which the counter triggers a
hardware assist to collect information on events. The hardware assist
takes a trap like snapshot of a subset of the machine registers.
This data is written to the Intel Debug-Store, which can be programmed
with a data threshold at which to raise a PMI.
With the PEBS hardware assist being trap like, the reported IP is always
one instruction after the actual instruction that triggered the event.
This implements a simple PEBS model that always takes a single PEBS event
at a time. This is done so that the interaction with the rest of the
system is as expected (freq adjust, period randomization, lbr,
callchains, etc.).
It adds an ABI element: perf_event_attr::precise, which indicates that we
wish to use this (constrained, but precise) mode.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arnaldo Carvalho de Melo <acme@infradead.org>
Cc: paulus@samba.org
Cc: eranian@google.com
Cc: robert.richter@amd.com
Cc: fweisbec@gmail.com
LKML-Reference: <20100304140100.392111285@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-03-02 18:52:12 +00:00
|
|
|
}
|
|
|
|
|
2012-06-06 00:56:48 +00:00
|
|
|
if (!event || bit >= x86_pmu.max_pebs_events)
|
perf, x86: Add PEBS infrastructure
This patch implements support for Intel Precise Event Based Sampling,
which is an alternative counter mode in which the counter triggers a
hardware assist to collect information on events. The hardware assist
takes a trap like snapshot of a subset of the machine registers.
This data is written to the Intel Debug-Store, which can be programmed
with a data threshold at which to raise a PMI.
With the PEBS hardware assist being trap like, the reported IP is always
one instruction after the actual instruction that triggered the event.
This implements a simple PEBS model that always takes a single PEBS event
at a time. This is done so that the interaction with the rest of the
system is as expected (freq adjust, period randomization, lbr,
callchains, etc.).
It adds an ABI element: perf_event_attr::precise, which indicates that we
wish to use this (constrained, but precise) mode.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arnaldo Carvalho de Melo <acme@infradead.org>
Cc: paulus@samba.org
Cc: eranian@google.com
Cc: robert.richter@amd.com
Cc: fweisbec@gmail.com
LKML-Reference: <20100304140100.392111285@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-03-02 18:52:12 +00:00
|
|
|
continue;
|
|
|
|
|
2010-04-08 21:03:20 +00:00
|
|
|
__intel_pmu_pebs_event(event, iregs, at);
|
perf, x86: Add PEBS infrastructure
This patch implements support for Intel Precise Event Based Sampling,
which is an alternative counter mode in which the counter triggers a
hardware assist to collect information on events. The hardware assist
takes a trap like snapshot of a subset of the machine registers.
This data is written to the Intel Debug-Store, which can be programmed
with a data threshold at which to raise a PMI.
With the PEBS hardware assist being trap like, the reported IP is always
one instruction after the actual instruction that triggered the event.
This implements a simple PEBS model that always takes a single PEBS event
at a time. This is done so that the interaction with the rest of the
system is as expected (freq adjust, period randomization, lbr,
callchains, etc.).
It adds an ABI element: perf_event_attr::precise, which indicates that we
wish to use this (constrained, but precise) mode.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arnaldo Carvalho de Melo <acme@infradead.org>
Cc: paulus@samba.org
Cc: eranian@google.com
Cc: robert.richter@amd.com
Cc: fweisbec@gmail.com
LKML-Reference: <20100304140100.392111285@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-03-02 18:52:12 +00:00
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
/*
|
|
|
|
* BTS, PEBS probe and setup
|
|
|
|
*/
|
|
|
|
|
2011-08-30 23:41:05 +00:00
|
|
|
void intel_ds_init(void)
|
perf, x86: Add PEBS infrastructure
This patch implements support for Intel Precise Event Based Sampling,
which is an alternative counter mode in which the counter triggers a
hardware assist to collect information on events. The hardware assist
takes a trap like snapshot of a subset of the machine registers.
This data is written to the Intel Debug-Store, which can be programmed
with a data threshold at which to raise a PMI.
With the PEBS hardware assist being trap like, the reported IP is always
one instruction after the actual instruction that triggered the event.
This implements a simple PEBS model that always takes a single PEBS event
at a time. This is done so that the interaction with the rest of the
system is as expected (freq adjust, period randomization, lbr,
callchains, etc.).
It adds an ABI element: perf_event_attr::precise, which indicates that we
wish to use this (constrained, but precise) mode.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arnaldo Carvalho de Melo <acme@infradead.org>
Cc: paulus@samba.org
Cc: eranian@google.com
Cc: robert.richter@amd.com
Cc: fweisbec@gmail.com
LKML-Reference: <20100304140100.392111285@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-03-02 18:52:12 +00:00
|
|
|
{
|
|
|
|
/*
|
|
|
|
* No support for 32bit formats
|
|
|
|
*/
|
|
|
|
if (!boot_cpu_has(X86_FEATURE_DTES64))
|
|
|
|
return;
|
|
|
|
|
|
|
|
x86_pmu.bts = boot_cpu_has(X86_FEATURE_BTS);
|
|
|
|
x86_pmu.pebs = boot_cpu_has(X86_FEATURE_PEBS);
|
|
|
|
if (x86_pmu.pebs) {
|
2010-03-03 16:07:40 +00:00
|
|
|
char pebs_type = x86_pmu.intel_cap.pebs_trap ? '+' : '-';
|
|
|
|
int format = x86_pmu.intel_cap.pebs_format;
|
perf, x86: Add PEBS infrastructure
This patch implements support for Intel Precise Event Based Sampling,
which is an alternative counter mode in which the counter triggers a
hardware assist to collect information on events. The hardware assist
takes a trap like snapshot of a subset of the machine registers.
This data is written to the Intel Debug-Store, which can be programmed
with a data threshold at which to raise a PMI.
With the PEBS hardware assist being trap like, the reported IP is always
one instruction after the actual instruction that triggered the event.
This implements a simple PEBS model that always takes a single PEBS event
at a time. This is done so that the interaction with the rest of the
system is as expected (freq adjust, period randomization, lbr,
callchains, etc.).
It adds an ABI element: perf_event_attr::precise, which indicates that we
wish to use this (constrained, but precise) mode.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arnaldo Carvalho de Melo <acme@infradead.org>
Cc: paulus@samba.org
Cc: eranian@google.com
Cc: robert.richter@amd.com
Cc: fweisbec@gmail.com
LKML-Reference: <20100304140100.392111285@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-03-02 18:52:12 +00:00
|
|
|
|
|
|
|
switch (format) {
|
|
|
|
case 0:
|
2010-03-03 16:07:40 +00:00
|
|
|
printk(KERN_CONT "PEBS fmt0%c, ", pebs_type);
|
perf, x86: Add PEBS infrastructure
This patch implements support for Intel Precise Event Based Sampling,
which is an alternative counter mode in which the counter triggers a
hardware assist to collect information on events. The hardware assist
takes a trap like snapshot of a subset of the machine registers.
This data is written to the Intel Debug-Store, which can be programmed
with a data threshold at which to raise a PMI.
With the PEBS hardware assist being trap like, the reported IP is always
one instruction after the actual instruction that triggered the event.
This implements a simple PEBS model that always takes a single PEBS event
at a time. This is done so that the interaction with the rest of the
system is as expected (freq adjust, period randomization, lbr,
callchains, etc.).
It adds an ABI element: perf_event_attr::precise, which indicates that we
wish to use this (constrained, but precise) mode.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arnaldo Carvalho de Melo <acme@infradead.org>
Cc: paulus@samba.org
Cc: eranian@google.com
Cc: robert.richter@amd.com
Cc: fweisbec@gmail.com
LKML-Reference: <20100304140100.392111285@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-03-02 18:52:12 +00:00
|
|
|
x86_pmu.pebs_record_size = sizeof(struct pebs_record_core);
|
|
|
|
x86_pmu.drain_pebs = intel_pmu_drain_pebs_core;
|
|
|
|
break;
|
|
|
|
|
|
|
|
case 1:
|
2010-03-03 16:07:40 +00:00
|
|
|
printk(KERN_CONT "PEBS fmt1%c, ", pebs_type);
|
perf, x86: Add PEBS infrastructure
This patch implements support for Intel Precise Event Based Sampling,
which is an alternative counter mode in which the counter triggers a
hardware assist to collect information on events. The hardware assist
takes a trap like snapshot of a subset of the machine registers.
This data is written to the Intel Debug-Store, which can be programmed
with a data threshold at which to raise a PMI.
With the PEBS hardware assist being trap like, the reported IP is always
one instruction after the actual instruction that triggered the event.
This implements a simple PEBS model that always takes a single PEBS event
at a time. This is done so that the interaction with the rest of the
system is as expected (freq adjust, period randomization, lbr,
callchains, etc.).
It adds an ABI element: perf_event_attr::precise, which indicates that we
wish to use this (constrained, but precise) mode.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arnaldo Carvalho de Melo <acme@infradead.org>
Cc: paulus@samba.org
Cc: eranian@google.com
Cc: robert.richter@amd.com
Cc: fweisbec@gmail.com
LKML-Reference: <20100304140100.392111285@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-03-02 18:52:12 +00:00
|
|
|
x86_pmu.pebs_record_size = sizeof(struct pebs_record_nhm);
|
|
|
|
x86_pmu.drain_pebs = intel_pmu_drain_pebs_nhm;
|
|
|
|
break;
|
|
|
|
|
2013-06-18 00:36:47 +00:00
|
|
|
case 2:
|
|
|
|
pr_cont("PEBS fmt2%c, ", pebs_type);
|
|
|
|
x86_pmu.pebs_record_size = sizeof(struct pebs_record_hsw);
|
2013-09-12 11:00:47 +00:00
|
|
|
x86_pmu.drain_pebs = intel_pmu_drain_pebs_nhm;
|
2013-06-18 00:36:47 +00:00
|
|
|
break;
|
|
|
|
|
perf, x86: Add PEBS infrastructure
This patch implements support for Intel Precise Event Based Sampling,
which is an alternative counter mode in which the counter triggers a
hardware assist to collect information on events. The hardware assist
takes a trap like snapshot of a subset of the machine registers.
This data is written to the Intel Debug-Store, which can be programmed
with a data threshold at which to raise a PMI.
With the PEBS hardware assist being trap like, the reported IP is always
one instruction after the actual instruction that triggered the event.
This implements a simple PEBS model that always takes a single PEBS event
at a time. This is done so that the interaction with the rest of the
system is as expected (freq adjust, period randomization, lbr,
callchains, etc.).
It adds an ABI element: perf_event_attr::precise, which indicates that we
wish to use this (constrained, but precise) mode.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arnaldo Carvalho de Melo <acme@infradead.org>
Cc: paulus@samba.org
Cc: eranian@google.com
Cc: robert.richter@amd.com
Cc: fweisbec@gmail.com
LKML-Reference: <20100304140100.392111285@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-03-02 18:52:12 +00:00
|
|
|
default:
|
2010-03-03 16:07:40 +00:00
|
|
|
printk(KERN_CONT "no PEBS fmt%d%c, ", format, pebs_type);
|
perf, x86: Add PEBS infrastructure
This patch implements support for Intel Precise Event Based Sampling,
which is an alternative counter mode in which the counter triggers a
hardware assist to collect information on events. The hardware assist
takes a trap like snapshot of a subset of the machine registers.
This data is written to the Intel Debug-Store, which can be programmed
with a data threshold at which to raise a PMI.
With the PEBS hardware assist being trap like, the reported IP is always
one instruction after the actual instruction that triggered the event.
This implements a simple PEBS model that always takes a single PEBS event
at a time. This is done so that the interaction with the rest of the
system is as expected (freq adjust, period randomization, lbr,
callchains, etc.).
It adds an ABI element: perf_event_attr::precise, which indicates that we
wish to use this (constrained, but precise) mode.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arnaldo Carvalho de Melo <acme@infradead.org>
Cc: paulus@samba.org
Cc: eranian@google.com
Cc: robert.richter@amd.com
Cc: fweisbec@gmail.com
LKML-Reference: <20100304140100.392111285@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-03-02 18:52:12 +00:00
|
|
|
x86_pmu.pebs = 0;
|
|
|
|
}
|
|
|
|
}
|
|
|
|
}
|
2013-03-15 13:26:07 +00:00
|
|
|
|
|
|
|
void perf_restore_debug_store(void)
|
|
|
|
{
|
2013-03-17 22:44:43 +00:00
|
|
|
struct debug_store *ds = __this_cpu_read(cpu_hw_events.ds);
|
|
|
|
|
2013-03-15 13:26:07 +00:00
|
|
|
if (!x86_pmu.bts && !x86_pmu.pebs)
|
|
|
|
return;
|
|
|
|
|
2013-03-17 22:44:43 +00:00
|
|
|
wrmsrl(MSR_IA32_DS_AREA, (unsigned long)ds);
|
2013-03-15 13:26:07 +00:00
|
|
|
}
|