| lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
|
Open Source and information security mailing list archives
| ||
|
Date: Sun, 16 Nov 2014 04:37:02 -0800
From: tip-bot for Peter Zijlstra <tipbot@...or.com>
To: linux-tip-commits@...r.kernel.org
Cc: peterz@...radead.org, linux-kernel@...r.kernel.org,
mingo@...nel.org, torvalds@...ux-foundation.org, acme@...nel.org,
tglx@...utronix.de, hpa@...or.com
Subject: [tip:perf/core] perf: Improve the perf_sample_data struct layout
Commit-ID: 2565711fb7d7c28e0cd93c8971b520d1b10b857c
Gitweb: http://git.kernel.org/tip/2565711fb7d7c28e0cd93c8971b520d1b10b857c
Author: Peter Zijlstra <peterz@...radead.org>
AuthorDate: Wed, 24 Sep 2014 13:48:42 +0200
Committer: Ingo Molnar <mingo@...nel.org>
CommitDate: Sun, 16 Nov 2014 11:42:04 +0100
perf: Improve the perf_sample_data struct layout
This patch reorders fields in the perf_sample_data struct in order to
minimize the number of cachelines touched in perf_sample_data_init().
It also removes some intializations which are redundant with the code
in kernel/events/core.c
Signed-off-by: Peter Zijlstra (Intel) <peterz@...radead.org>
Link: http://lkml.kernel.org/r/1411559322-16548-7-git-send-email-eranian@google.com
Cc: cebbert.lkml@...il.com
Cc: Arnaldo Carvalho de Melo <acme@...nel.org>
Cc: jolsa@...hat.com
Cc: Linus Torvalds <torvalds@...ux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@...nel.org>
---
include/linux/perf_event.h | 34 +++++++++++++++++-----------------
kernel/events/core.c | 16 ++++++++--------
2 files changed, 25 insertions(+), 25 deletions(-)
diff --git a/include/linux/perf_event.h b/include/linux/perf_event.h
index 68d46d5..486e84c 100644
--- a/include/linux/perf_event.h
+++ b/include/linux/perf_event.h
@@ -580,35 +580,40 @@ extern u64 perf_event_read_value(struct perf_event *event,
struct perf_sample_data {
- u64 type;
+ /*
+ * Fields set by perf_sample_data_init(), group so as to
+ * minimize the cachelines touched.
+ */
+ u64 addr;
+ struct perf_raw_record *raw;
+ struct perf_branch_stack *br_stack;
+ u64 period;
+ u64 weight;
+ u64 txn;
+ union perf_mem_data_src data_src;
+ /*
+ * The other fields, optionally {set,used} by
+ * perf_{prepare,output}_sample().
+ */
+ u64 type;
u64 ip;
struct {
u32 pid;
u32 tid;
} tid_entry;
u64 time;
- u64 addr;
u64 id;
u64 stream_id;
struct {
u32 cpu;
u32 reserved;
} cpu_entry;
- u64 period;
- union perf_mem_data_src data_src;
struct perf_callchain_entry *callchain;
- struct perf_raw_record *raw;
- struct perf_branch_stack *br_stack;
struct perf_regs regs_user;
struct perf_regs regs_intr;
u64 stack_user_size;
- u64 weight;
- /*
- * Transaction flags for abort events:
- */
- u64 txn;
-};
+} ____cacheline_aligned;
/* default value for data source */
#define PERF_MEM_NA (PERF_MEM_S(OP, NA) |\
@@ -625,14 +630,9 @@ static inline void perf_sample_data_init(struct perf_sample_data *data,
data->raw = NULL;
data->br_stack = NULL;
data->period = period;
- data->regs_user.abi = PERF_SAMPLE_REGS_ABI_NONE;
- data->regs_user.regs = NULL;
- data->stack_user_size = 0;
data->weight = 0;
data->data_src.val = PERF_MEM_NA;
data->txn = 0;
- data->regs_intr.abi = PERF_SAMPLE_REGS_ABI_NONE;
- data->regs_intr.regs = NULL;
}
extern void perf_output_sample(struct perf_output_handle *handle,
diff --git a/kernel/events/core.c b/kernel/events/core.c
index c2be159..3e19d3e 100644
--- a/kernel/events/core.c
+++ b/kernel/events/core.c
@@ -4471,8 +4471,11 @@ static void perf_sample_regs_user(struct perf_regs *regs_user,
}
if (regs) {
- regs_user->regs = regs;
regs_user->abi = perf_reg_abi(current);
+ regs_user->regs = regs;
+ } else {
+ regs_user->abi = PERF_SAMPLE_REGS_ABI_NONE;
+ regs_user->regs = NULL;
}
}
@@ -4947,12 +4950,13 @@ void perf_prepare_sample(struct perf_event_header *header,
header->size += size;
}
+ if (sample_type & (PERF_SAMPLE_REGS_USER | PERF_SAMPLE_STACK_USER))
+ perf_sample_regs_user(&data->regs_user, regs);
+
if (sample_type & PERF_SAMPLE_REGS_USER) {
/* regs dump ABI info */
int size = sizeof(u64);
- perf_sample_regs_user(&data->regs_user, regs);
-
if (data->regs_user.regs) {
u64 mask = event->attr.sample_regs_user;
size += hweight64(mask) * sizeof(u64);
@@ -4968,15 +4972,11 @@ void perf_prepare_sample(struct perf_event_header *header,
* in case new sample type is added, because we could eat
* up the rest of the sample size.
*/
- struct perf_regs *uregs = &data->regs_user;
u16 stack_size = event->attr.sample_stack_user;
u16 size = sizeof(u64);
- if (!uregs->abi)
- perf_sample_regs_user(uregs, regs);
-
stack_size = perf_sample_ustack_size(stack_size, header->size,
- uregs->regs);
+ data->regs_user.regs);
/*
* If there is something to dump, add space for the dump
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
Powered by blists - more mailing lists