| 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: Fri, 17 Apr 2020 12:02:40 -0300
From: Arnaldo Carvalho de Melo <arnaldo.melo@...il.com>
To: kan.liang@...ux.intel.com
Cc: jolsa@...hat.com, peterz@...radead.org, mingo@...hat.com,
linux-kernel@...r.kernel.org, namhyung@...nel.org,
adrian.hunter@...el.com, mathieu.poirier@...aro.org,
ravi.bangoria@...ux.ibm.com, alexey.budankov@...ux.intel.com,
vitaly.slobodskoy@...el.com, pavel.gerasimov@...el.com,
mpe@...erman.id.au, eranian@...gle.com, ak@...ux.intel.com
Subject: Re: [PATCH V4 10/17] perf tools: Save previous sample for LBR
stitching approach
Em Thu, Mar 19, 2020 at 01:25:10PM -0700, kan.liang@...ux.intel.com escreveu:
> From: Kan Liang <kan.liang@...ux.intel.com>
>
> To retrieve the overwritten LBRs from previous sample for LBR stitching
> approach, perf has to save the previous sample.
>
> Only allocate the struct lbr_stitch once, when LBR stitching approach
> is enabled and kernel supports hw_idx.
Applied + this one on top:
diff --git a/tools/perf/util/machine.c b/tools/perf/util/machine.c
index 59778f5aec2a..a54ca09a1d00 100644
--- a/tools/perf/util/machine.c
+++ b/tools/perf/util/machine.c
@@ -2297,7 +2297,7 @@ static bool alloc_lbr_stitch(struct thread *thread)
if (thread->lbr_stitch)
return true;
- thread->lbr_stitch = calloc(1, sizeof(struct lbr_stitch));
+ thread->lbr_stitch = zalloc(sizeof(*thread->lbr_stitch));
if (!thread->lbr_stitch)
goto err;
diff --git a/tools/perf/util/thread.h b/tools/perf/util/thread.h
index f65a84a25f93..34eb61cee6a4 100644
--- a/tools/perf/util/thread.h
+++ b/tools/perf/util/thread.h
@@ -5,6 +5,7 @@
#include <linux/refcount.h>
#include <linux/rbtree.h>
#include <linux/list.h>
+#include <linux/zalloc.h>
#include <stdio.h>
#include <unistd.h>
#include <sys/types.h>
@@ -153,7 +154,7 @@ static inline bool thread__is_filtered(struct thread *thread)
static inline void thread__free_stitch_list(struct thread *thread)
{
- free(thread->lbr_stitch);
+ zfree(&thread->lbr_stitch);
}
#endif /* __PERF_THREAD_H */
> Reviewed-by: Andi Kleen <ak@...ux.intel.com>
> Signed-off-by: Kan Liang <kan.liang@...ux.intel.com>
> ---
> tools/perf/util/machine.c | 23 +++++++++++++++++++++++
> tools/perf/util/thread.c | 1 +
> tools/perf/util/thread.h | 11 +++++++++++
> 3 files changed, 35 insertions(+)
>
> diff --git a/tools/perf/util/machine.c b/tools/perf/util/machine.c
> index f1661dd3ca69..d91e11bfc8ca 100644
> --- a/tools/perf/util/machine.c
> +++ b/tools/perf/util/machine.c
> @@ -2261,6 +2261,21 @@ static int lbr_callchain_add_lbr_ip(struct thread *thread,
> return 0;
> }
>
> +static bool alloc_lbr_stitch(struct thread *thread)
> +{
> + if (thread->lbr_stitch)
> + return true;
> +
> + thread->lbr_stitch = calloc(1, sizeof(struct lbr_stitch));
> + if (!thread->lbr_stitch)
> + goto err;
> +
> +err:
> + pr_warning("Failed to allocate space for stitched LBRs. Disable LBR stitch\n");
> + thread->lbr_stitch_enable = false;
> + return false;
> +}
> +
> /*
> * Recolve LBR callstack chain sample
> * Return:
> @@ -2277,6 +2292,7 @@ static int resolve_lbr_callchain_sample(struct thread *thread,
> {
> struct ip_callchain *chain = sample->callchain;
> int chain_nr = min(max_stack, (int)chain->nr), i;
> + struct lbr_stitch *lbr_stitch;
> u64 branch_from = 0;
> int err;
>
> @@ -2289,6 +2305,13 @@ static int resolve_lbr_callchain_sample(struct thread *thread,
> if (i == chain_nr)
> return 0;
>
> + if (thread->lbr_stitch_enable && !sample->no_hw_idx &&
> + alloc_lbr_stitch(thread)) {
> + lbr_stitch = thread->lbr_stitch;
> +
> + memcpy(&lbr_stitch->prev_sample, sample, sizeof(*sample));
> + }
> +
> if (callchain_param.order == ORDER_CALLEE) {
> /* Add kernel ip */
> err = lbr_callchain_add_kernel_ip(thread, cursor, sample,
> diff --git a/tools/perf/util/thread.c b/tools/perf/util/thread.c
> index 1f080db23615..8d0da260c84c 100644
> --- a/tools/perf/util/thread.c
> +++ b/tools/perf/util/thread.c
> @@ -111,6 +111,7 @@ void thread__delete(struct thread *thread)
>
> exit_rwsem(&thread->namespaces_lock);
> exit_rwsem(&thread->comm_lock);
> + thread__free_stitch_list(thread);
> free(thread);
> }
>
> diff --git a/tools/perf/util/thread.h b/tools/perf/util/thread.h
> index 95294050cff2..f65a84a25f93 100644
> --- a/tools/perf/util/thread.h
> +++ b/tools/perf/util/thread.h
> @@ -13,6 +13,7 @@
> #include <strlist.h>
> #include <intlist.h>
> #include "rwsem.h"
> +#include "event.h"
>
> struct addr_location;
> struct map;
> @@ -20,6 +21,10 @@ struct perf_record_namespaces;
> struct thread_stack;
> struct unwind_libunwind_ops;
>
> +struct lbr_stitch {
> + struct perf_sample prev_sample;
> +};
> +
> struct thread {
> union {
> struct rb_node rb_node;
> @@ -49,6 +54,7 @@ struct thread {
>
> /* LBR call stack stitch */
> bool lbr_stitch_enable;
> + struct lbr_stitch *lbr_stitch;
> };
>
> struct machine;
> @@ -145,4 +151,9 @@ static inline bool thread__is_filtered(struct thread *thread)
> return false;
> }
>
> +static inline void thread__free_stitch_list(struct thread *thread)
> +{
> + free(thread->lbr_stitch);
> +}
> +
> #endif /* __PERF_THREAD_H */
> --
> 2.17.1
>
--
- Arnaldo
Powered by blists - more mailing lists