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From: Tzvetomir Stoyanov <tz.stoyanov@gmail.com>
To: Slavomir Kaslev <slavomir.kaslev@gmail.com>
Cc: Steven Rostedt <rostedt@goodmis.org>, linux-trace-devel@vger.kernel.org
Subject: Re: [PATCH v15 16/18] trace-cmd: Basic infrastructure for host - guest timestamp synchronization
Date: Thu, 28 Nov 2019 17:27:40 +0200	[thread overview]
Message-ID: <CAPpZLN6LJOxxZkw8R4qP4i6BfUBz8+Le8SydsB9WwnWaaNqJag@mail.gmail.com> (raw)
In-Reply-To: <CAE0o1Nv33cEQGGX92XDCW7Y_E8CZ2uZ-ZKV=-_TkMeh3LB02DQ@mail.gmail.com>

On Thu, Nov 28, 2019 at 5:08 PM Slavomir Kaslev
<slavomir.kaslev@gmail.com> wrote:
>
...
> > +       if (buf_size && payload && payload_size) {
> > +               if (*payload_size) {
> > +                       if (*payload_size != buf_size || *payload == NULL) {
> > +                               ret = -ENOMEM;
>
> Returning ENOMEM in this case is confusing. If this case is intended
> make it so that we don't allocate on each tracecmd_msg_recv_time_sync,
> maybe do realloc() here instead?
>
The main use case is to avoid the memory allocation at all, if the
payload is with known size. The user can pass a buffer with given
size, and the error should handle the case when the payload size is
not the one, expected by the user.

> --
> Slavomir Kaslev

Thanks !

-- 
Tzvetomir (Ceco) Stoyanov
VMware Open Source Technology Center

  reply	other threads:[~2019-11-28 15:27 UTC|newest]

Thread overview: 28+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-11-28  8:53 [PATCH v15 00/18]Timestamp synchronization of host - guest tracing session Tzvetomir Stoyanov (VMware)
2019-11-28  8:53 ` [PATCH v15 01/18] trace-cmd: Implement new lib API: tracecmd_local_events_system() Tzvetomir Stoyanov (VMware)
2019-11-28  8:53 ` [PATCH v15 02/18] trace-cmd: Add support for negative time offsets in trace.dat file Tzvetomir Stoyanov (VMware)
2019-11-28  8:53 ` [PATCH v15 03/18] trace-cmd: Add implementations of htonll() and ntohll() Tzvetomir Stoyanov (VMware)
2019-11-28  8:53 ` [PATCH v15 04/18] trace-cmd: Add new library APIs for ftrace instances Tzvetomir Stoyanov (VMware)
2019-11-28  8:53 ` [PATCH v15 05/18] trace-cmd: Add new library API for local CPU count Tzvetomir Stoyanov (VMware)
2019-11-28  8:53 ` [PATCH v15 06/18] trace-cmd: Add new library API for reading ftrace buffers Tzvetomir Stoyanov (VMware)
2019-11-28  8:53 ` [PATCH v15 07/18] trace-cmd: Find and store pids of tasks, which run virtual CPUs of given VM Tzvetomir Stoyanov (VMware)
2019-11-28  8:53 ` [PATCH v15 08/18] trace-cmd: Implement new API tracecmd_add_option_v() Tzvetomir Stoyanov (VMware)
2019-11-28  8:54 ` [PATCH v15 09/18] trace-cmd: Add new API to generate a unique ID of the tracing session Tzvetomir Stoyanov (VMware)
2019-11-28  8:54 ` [PATCH v15 10/18] trace-cmd: Store the session tracing ID in the trace.dat file Tzvetomir Stoyanov (VMware)
2019-11-28  8:54 ` [PATCH v15 11/18] trace-cmd: Exchange tracing IDs between host and guest Tzvetomir Stoyanov (VMware)
2019-11-28 14:34   ` Slavomir Kaslev
2019-11-28 14:58     ` Tzvetomir Stoyanov
2019-11-29 10:22       ` Tzvetomir Stoyanov
2019-11-28  8:54 ` [PATCH v15 12/18] trace-cmd: Implement new option in trace.dat file: TRACECMD_OPTION_TIME_SHIFT Tzvetomir Stoyanov (VMware)
2019-11-28  8:54 ` [PATCH v15 13/18] trace-cmd: Add guest information in host's trace.dat file Tzvetomir Stoyanov (VMware)
2019-11-28  8:54 ` [PATCH v15 14/18] trace-cmd: Add host trace clock as guest trace argument Tzvetomir Stoyanov (VMware)
2019-11-28 14:45   ` Slavomir Kaslev
2019-11-28 15:05     ` Tzvetomir Stoyanov
2019-11-28  8:54 ` [PATCH v15 15/18] trace-cmd: Refactor few trace-cmd internal functions Tzvetomir Stoyanov (VMware)
2019-11-28 14:51   ` Slavomir Kaslev
2019-11-28 15:08     ` Tzvetomir Stoyanov
2019-11-28  8:54 ` [PATCH v15 16/18] trace-cmd: Basic infrastructure for host - guest timestamp synchronization Tzvetomir Stoyanov (VMware)
2019-11-28 15:08   ` Slavomir Kaslev
2019-11-28 15:27     ` Tzvetomir Stoyanov [this message]
2019-11-28  8:54 ` [PATCH v15 17/18] trace-cmd: [POC] PTP-like algorithm " Tzvetomir Stoyanov (VMware)
2019-11-28  8:54 ` [PATCH v15 18/18] trace-cmd: Debug scripts for " Tzvetomir Stoyanov (VMware)

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