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x86_64-pc-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-Rspamd-Queue-Id: DCE241C0004 X-Rspam-User: X-Stat-Signature: rjtxz7t9fy75ub433zy1udff48g39pn5 X-Rspamd-Server: rspam03 X-HE-Tag: 1684765765-491929 X-HE-Meta: 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 AXIyFwkH 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 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Fri, 19 May 2023 08:40:38 +0100 David Howells wrote: > For the splice from the trace seq buffer, just use direct_splice_read(). > > In the future, something better can probably be done by gifting pages from > seq->buf into the pipe, but that would require changing seq->buf into a > vmap over an array of pages. If you can give me a POC of what needs to be done, I could possibly implement it. > > Signed-off-by: David Howells > cc: Christoph Hellwig > cc: Al Viro > cc: Jens Axboe > cc: Steven Rostedt > cc: Masami Hiramatsu > cc: linux-kernel@vger.kernel.org > cc: linux-trace-kernel@vger.kernel.org > cc: linux-fsdevel@vger.kernel.org > cc: linux-block@vger.kernel.org > cc: linux-mm@kvack.org > --- > kernel/trace/trace.c | 2 +- Acked-by: Steven Rostedt (Google) -- Steve > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c > index ebc59781456a..b664020efcb7 100644 > --- a/kernel/trace/trace.c > +++ b/kernel/trace/trace.c > @@ -5171,7 +5171,7 @@ static const struct file_operations tracing_fops = { > .open = tracing_open, > .read = seq_read, > .read_iter = seq_read_iter, > - .splice_read = generic_file_splice_read, > + .splice_read = direct_splice_read, > .write = tracing_write_stub, > .llseek = tracing_lseek, > .release = tracing_release,