From: Arnaldo Carvalho de Melo <acme@kernel.org>
To: Ingo Molnar <mingo@kernel.org>
Cc: linux-kernel@vger.kernel.org,
Elena Reshetova <elena.reshetova@intel.com>,
David Windsor <dwindsor@gmail.com>,
Hans Liljestrand <ishkamiel@gmail.com>,
Kees Kook <keescook@chromium.org>,
Alexander Shishkin <alexander.shishkin@linux.intel.com>,
Andrew Morton <akpm@linux-foundation.org>,
Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
Jiri Olsa <jolsa@kernel.org>, Mark Rutland <mark.rutland@arm.com>,
Matija Glavinic Pecotic <matija.glavinic-pecotic.ext@nokia.com>,
Peter Zijlstra <peterz@infradead.org>,
alsa-devel@alsa-project.org,
Arnaldo Carvalho de Melo <acme@redhat.com>
Subject: [PATCH 12/35] perf comm: Convert comm_str.refcnt from atomic_t to refcount_t
Date: Mon, 6 Mar 2017 16:38:02 -0300 [thread overview]
Message-ID: <20170306193825.24011-13-acme@kernel.org> (raw)
In-Reply-To: <20170306193825.24011-1-acme@kernel.org>
From: Elena Reshetova <elena.reshetova@intel.com>
The refcount_t type and corresponding API should be used instead of
atomic_t when the variable is used as a reference counter.
This allows to avoid accidental refcounter overflows that might lead to
use-after-free situations.
Signed-off-by: Elena Reshetova <elena.reshetova@intel.com>
Signed-off-by: David Windsor <dwindsor@gmail.com>
Signed-off-by: Hans Liljestrand <ishkamiel@gmail.com>
Signed-off-by: Kees Kook <keescook@chromium.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: David Windsor <dwindsor@gmail.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Hans Liljestrand <ishkamiel@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kees Kook <keescook@chromium.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Matija Glavinic Pecotic <matija.glavinic-pecotic.ext@nokia.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: alsa-devel@alsa-project.org
Link: http://lkml.kernel.org/r/1487691303-31858-4-git-send-email-elena.reshetova@intel.com
[ Reinstated comm_str__get() function, needed when reusing entries in the rbtree ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
---
tools/perf/util/comm.c | 15 ++++++---------
1 file changed, 6 insertions(+), 9 deletions(-)
diff --git a/tools/perf/util/comm.c b/tools/perf/util/comm.c
index 21b7ff382c3f..32837b6f7879 100644
--- a/tools/perf/util/comm.c
+++ b/tools/perf/util/comm.c
@@ -2,12 +2,12 @@
#include "util.h"
#include <stdlib.h>
#include <stdio.h>
-#include <linux/atomic.h>
+#include <linux/refcount.h>
struct comm_str {
char *str;
struct rb_node rb_node;
- atomic_t refcnt;
+ refcount_t refcnt;
};
/* Should perhaps be moved to struct machine */
@@ -16,13 +16,13 @@ static struct rb_root comm_str_root;
static struct comm_str *comm_str__get(struct comm_str *cs)
{
if (cs)
- atomic_inc(&cs->refcnt);
+ refcount_inc(&cs->refcnt);
return cs;
}
static void comm_str__put(struct comm_str *cs)
{
- if (cs && atomic_dec_and_test(&cs->refcnt)) {
+ if (cs && refcount_dec_and_test(&cs->refcnt)) {
rb_erase(&cs->rb_node, &comm_str_root);
zfree(&cs->str);
free(cs);
@@ -43,7 +43,7 @@ static struct comm_str *comm_str__alloc(const char *str)
return NULL;
}
- atomic_set(&cs->refcnt, 0);
+ refcount_set(&cs->refcnt, 1);
return cs;
}
@@ -61,7 +61,7 @@ static struct comm_str *comm_str__findnew(const char *str, struct rb_root *root)
cmp = strcmp(str, iter->str);
if (!cmp)
- return iter;
+ return comm_str__get(iter);
if (cmp < 0)
p = &(*p)->rb_left;
@@ -95,8 +95,6 @@ struct comm *comm__new(const char *str, u64 timestamp, bool exec)
return NULL;
}
- comm_str__get(comm->comm_str);
-
return comm;
}
@@ -108,7 +106,6 @@ int comm__override(struct comm *comm, const char *str, u64 timestamp, bool exec)
if (!new)
return -ENOMEM;
- comm_str__get(new);
comm_str__put(old);
comm->comm_str = new;
comm->start = timestamp;
--
2.9.3
next prev parent reply other threads:[~2017-03-06 19:42 UTC|newest]
Thread overview: 39+ messages / expand[flat|nested] mbox.gz Atom feed top
2017-03-06 19:37 [GIT PULL 00/35] perf/core improvements and fixes Arnaldo Carvalho de Melo
2017-03-06 19:37 ` [PATCH 01/35] perf vendor events: Add mapping for KnightsMill PMU events Arnaldo Carvalho de Melo
2017-03-06 19:37 ` [PATCH 02/35] perf stat: Issue a HW watchdog disable hint Arnaldo Carvalho de Melo
2017-03-06 19:37 ` [PATCH 03/35] tools include: Adopt __compiletime_error Arnaldo Carvalho de Melo
2017-03-06 19:37 ` [PATCH 04/35] tools arch x86: Include asm/cmpxchg.h Arnaldo Carvalho de Melo
2017-03-06 19:37 ` [PATCH 05/35] tools arch x86: Introduce atomic_cmpxchg() Arnaldo Carvalho de Melo
2017-03-06 19:37 ` [PATCH 06/35] tools include: Introduce atomic_cmpxchg_{relaxed,release}() Arnaldo Carvalho de Melo
2017-03-06 19:37 ` [PATCH 07/35] tools include: Provide gcc based cmpxchg fallback for !x86 Arnaldo Carvalho de Melo
2017-03-06 19:37 ` [PATCH 08/35] tools include: Add UINT_MAX def to kernel.h Arnaldo Carvalho de Melo
2017-03-06 19:37 ` [PATCH 09/35] tools include: Adopt kernel's refcount.h Arnaldo Carvalho de Melo
2017-03-06 19:38 ` [PATCH 10/35] perf cgroup: Convert cgroup_sel.refcnt from atomic_t to refcount_t Arnaldo Carvalho de Melo
2017-03-06 19:38 ` [PATCH 11/35] perf cpumap: Convert cpu_map.refcnt " Arnaldo Carvalho de Melo
2017-03-06 19:38 ` Arnaldo Carvalho de Melo [this message]
2017-03-06 19:38 ` [PATCH 13/35] perf dso: Convert dso.refcnt " Arnaldo Carvalho de Melo
2017-03-06 19:38 ` [PATCH 14/35] perf map: Convert map.refcnt " Arnaldo Carvalho de Melo
2017-03-06 19:38 ` [PATCH 15/35] perf map: Convert map_groups.refcnt " Arnaldo Carvalho de Melo
2017-03-06 19:38 ` [PATCH 16/35] perf evlist: Convert perf_map.refcnt " Arnaldo Carvalho de Melo
2017-03-06 19:38 ` [PATCH 17/35] perf thread: convert thread.refcnt " Arnaldo Carvalho de Melo
2017-03-06 19:38 ` [PATCH 18/35] perf thread_map: Convert thread_map.refcnt " Arnaldo Carvalho de Melo
2017-03-06 19:38 ` [PATCH 19/35] perf evlist: Clarify a bit the use of perf_mmap->refcnt Arnaldo Carvalho de Melo
2017-03-06 19:38 ` [PATCH 20/35] perf tools: Allow sorting by symbol size Arnaldo Carvalho de Melo
2017-03-06 19:38 ` [PATCH 21/35] perf ftrace: Add support for --pid option Arnaldo Carvalho de Melo
2017-03-06 19:38 ` [PATCH 22/35] perf cpumap: Introduce cpu_map__snprint_mask() Arnaldo Carvalho de Melo
2017-03-06 19:38 ` [PATCH 23/35] perf ftrace: Add support for -a and -C option Arnaldo Carvalho de Melo
2017-03-06 19:38 ` [PATCH 24/35] perf ftrace: Use pager for displaying result Arnaldo Carvalho de Melo
2017-03-06 19:38 ` [PATCH 25/35] kretprobes: Ensure probe location is at function entry Arnaldo Carvalho de Melo
2017-03-06 19:38 ` [PATCH 26/35] trace/kprobes: Allow return probes with offsets and absolute addresses Arnaldo Carvalho de Melo
2017-03-06 19:38 ` [PATCH 27/35] perf probe: Generalize probe event file open routine Arnaldo Carvalho de Melo
2017-03-06 19:38 ` [PATCH 28/35] perf intel-PT/BTS: Add missing initialization Arnaldo Carvalho de Melo
2017-03-06 19:38 ` [PATCH 29/35] trace/kprobes: Add back warning about offset in return probes Arnaldo Carvalho de Melo
2017-03-06 19:38 ` [PATCH 30/35] perf tools: Force uncore events to system wide monitoring Arnaldo Carvalho de Melo
2017-03-06 19:38 ` [PATCH 31/35] tools build: Add test for sched_getcpu() Arnaldo Carvalho de Melo
2017-03-06 19:38 ` [PATCH 32/35] perf bench futex: Use __maybe_unused Arnaldo Carvalho de Melo
2017-03-06 19:38 ` [PATCH 33/35] perf bench futex: Fix build on musl + clang Arnaldo Carvalho de Melo
2017-09-08 8:04 ` Jörg Krause
2017-09-08 13:47 ` Arnaldo Carvalho de Melo
2017-03-06 19:38 ` [PATCH 34/35] tools build: Use the same CC for feature detection and actual build Arnaldo Carvalho de Melo
2017-03-06 19:38 ` [PATCH 35/35] perf bench numa: Add more comment for -c option Arnaldo Carvalho de Melo
2017-03-07 7:17 ` [GIT PULL 00/35] perf/core improvements and fixes Ingo Molnar
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20170306193825.24011-13-acme@kernel.org \
--to=acme@kernel.org \
--cc=acme@redhat.com \
--cc=akpm@linux-foundation.org \
--cc=alexander.shishkin@linux.intel.com \
--cc=alsa-devel@alsa-project.org \
--cc=dwindsor@gmail.com \
--cc=elena.reshetova@intel.com \
--cc=gregkh@linuxfoundation.org \
--cc=ishkamiel@gmail.com \
--cc=jolsa@kernel.org \
--cc=keescook@chromium.org \
--cc=linux-kernel@vger.kernel.org \
--cc=mark.rutland@arm.com \
--cc=matija.glavinic-pecotic.ext@nokia.com \
--cc=mingo@kernel.org \
--cc=peterz@infradead.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).