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From: Jiri Olsa <jolsa@redhat.com>
To: Namhyung Kim <namhyung@kernel.org>
Cc: Jiri Olsa <jolsa@kernel.org>,
	Arnaldo Carvalho de Melo <acme@kernel.org>,
	lkml <linux-kernel@vger.kernel.org>,
	Peter Zijlstra <a.p.zijlstra@chello.nl>,
	Ingo Molnar <mingo@kernel.org>,
	Mark Rutland <mark.rutland@arm.com>,
	Alexander Shishkin <alexander.shishkin@linux.intel.com>,
	Michael Petlan <mpetlan@redhat.com>,
	Ian Rogers <irogers@google.com>,
	Stephane Eranian <eranian@google.com>,
	Alexei Budankov <abudankov@huawei.com>
Subject: Re: [PATCH 12/22] perf daemon: Allow only one daemon over base directory
Date: Tue, 19 Jan 2021 18:44:32 +0100	[thread overview]
Message-ID: <20210119174432.GC1717058@krava> (raw)
In-Reply-To: <CAM9d7cj7TaJH3CtkQDjfD9OuV77LzbcY4y_EW7PWi+winu8gcw@mail.gmail.com>

On Tue, Jan 19, 2021 at 02:37:42PM +0900, Namhyung Kim wrote:

SNIP

> >
> > +static int check_lock(struct daemon *daemon)
> > +{
> > +       char path[PATH_MAX];
> > +       char buf[20];
> > +       int fd, pid;
> > +       ssize_t len;
> > +
> > +       scnprintf(path, sizeof(path), "%s/lock", daemon->base);
> > +
> > +       fd = open(path, O_RDWR|O_CREAT|O_CLOEXEC, 0640);
> > +       if (fd < 0)
> > +               return -1;
> > +
> > +       if (lockf(fd, F_TLOCK, 0) < 0) {
> > +               filename__read_int(path, &pid);
> > +               fprintf(stderr, "failed: another perf daemon (pid %d) owns %s\n",
> > +                       pid, daemon->base);
> > +               return -1;
> > +       }
> 
> So the fd is (a kind of) leaked and the lock is released only when
> the daemon is going to die, right?

yes, that's the idea, I'll put it in some comment

thanks,
jirka


  reply	other threads:[~2021-01-19 22:05 UTC|newest]

Thread overview: 44+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-01-02 22:04 [PATCHv2 00/22] perf tools: Add daemon command Jiri Olsa
2021-01-02 22:04 ` [PATCH 01/22] perf tools: Make perf_config_from_file static Jiri Olsa
2021-01-18 15:51   ` Arnaldo Carvalho de Melo
2021-01-02 22:04 ` [PATCH 02/22] perf tools: Add config set interface Jiri Olsa
2021-01-18 15:53   ` Arnaldo Carvalho de Melo
2021-01-02 22:04 ` [PATCH 03/22] perf tools: Add debug_set_display_time function Jiri Olsa
2021-01-18 16:02   ` Arnaldo Carvalho de Melo
2021-01-19 14:59   ` Arnaldo Carvalho de Melo
2021-01-19 17:39     ` Jiri Olsa
2021-01-19 19:42       ` Arnaldo Carvalho de Melo
2021-01-02 22:04 ` [PATCH 04/22] perf tools: Add perf_home_perfconfig function Jiri Olsa
2021-01-18 16:05   ` Arnaldo Carvalho de Melo
2021-01-02 22:04 ` [PATCH 05/22] perf tools: Make perf_config_system global Jiri Olsa
2021-01-18 16:03   ` Arnaldo Carvalho de Melo
2021-01-02 22:04 ` [PATCH 06/22] perf tools: Make perf_config_global gobal Jiri Olsa
2021-01-18 16:05   ` Arnaldo Carvalho de Melo
2021-01-02 22:04 ` [PATCH 07/22] perf daemon: Add daemon command Jiri Olsa
2021-01-19  4:08   ` Namhyung Kim
2021-01-19 18:31     ` Jiri Olsa
2021-01-21  4:53       ` Namhyung Kim
2021-01-27  7:09   ` Namhyung Kim
2021-01-27 22:01     ` Jiri Olsa
2021-01-02 22:04 ` [PATCH 08/22] perf daemon: Add config file change check Jiri Olsa
2021-01-19  5:31   ` Namhyung Kim
2021-01-19 17:49     ` Jiri Olsa
2021-01-21  4:54       ` Namhyung Kim
2021-01-02 22:04 ` [PATCH 09/22] perf daemon: Add signalfd support Jiri Olsa
2021-01-02 22:04 ` [PATCH 10/22] perf daemon: Add signal command Jiri Olsa
2021-01-02 22:04 ` [PATCH 11/22] perf daemon: Add stop command Jiri Olsa
2021-01-19  5:35   ` Namhyung Kim
2021-01-02 22:04 ` [PATCH 12/22] perf daemon: Allow only one daemon over base directory Jiri Olsa
2021-01-19  5:37   ` Namhyung Kim
2021-01-19 17:44     ` Jiri Olsa [this message]
2021-01-02 22:04 ` [PATCH 13/22] perf daemon: Set control fifo for session Jiri Olsa
2021-01-02 22:04 ` [PATCH 14/22] perf daemon: Add ping command Jiri Olsa
2021-01-02 22:04 ` [PATCH 15/22] perf daemon: Use control to stop session Jiri Olsa
2021-01-02 22:04 ` [PATCH 16/22] perf daemon: Add up time for daemon/session list Jiri Olsa
2021-01-02 22:04 ` [PATCH 17/22] perf daemon: Add man page for perf-daemon Jiri Olsa
2021-01-02 22:04 ` [PATCH 18/22] perf test: Add daemon list command test Jiri Olsa
2021-01-02 22:04 ` [PATCH 19/22] perf test: Add daemon reconfig test Jiri Olsa
2021-01-02 22:04 ` [PATCH 20/22] perf test: Add daemon stop command test Jiri Olsa
2021-01-02 22:04 ` [PATCH 21/22] perf test: Add daemon signal " Jiri Olsa
2021-01-02 22:04 ` [PATCH 22/22] perf test: Add daemon ping " Jiri Olsa
2021-01-18 12:55 ` [PATCHv2 00/22] perf tools: Add daemon command Jiri Olsa

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