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From: Richard Henderson <richard.henderson@linaro.org>
To: qemu-devel@nongnu.org
Cc: laurent@vivier.eu, evgreen@chromium.org, peter.maydell@linaro.org
Subject: [Qemu-devel] [PATCH 0/1] util/path: Do not cache all filenames at startup
Date: Tue, 16 Apr 2019 19:32:24 -1000	[thread overview]
Message-ID: <20190417053225.27505-1-richard.henderson@linaro.org> (raw)

This is a third variant attempting to fix the problem of
the -L interp_prefix handling not coping well pointing to
a full chroot.

Previous versions include:
https://lists.gnu.org/archive/html/qemu-devel/2018-05/msg06592.html
https://lists.gnu.org/archive/html/qemu-devel/2018-05/msg07304.html

Both of the other versions keep an open file descriptor to
the directory that is interp_prefix.  While this seems to be
efficient, they also leak a file descriptor into the guest.
This has follow-on effects on the emulation, causing failures
e.g. within the LTP testsuite.

This version uses only string manipulation and access(2).

A plausible criticism of this is the mutex and the cache.
Are they really needed?  I have no idea.  I can imagine
removing that is actually more efficient, not needing a
lock around a shared data structure.

Comments?


r~


Richard Henderson (1):
  util/path: Do not cache all filenames at startup

 util/path.c | 211 ++++++++++++++--------------------------------------
 1 file changed, 57 insertions(+), 154 deletions(-)

-- 
2.17.1

WARNING: multiple messages have this Message-ID (diff)
From: Richard Henderson <richard.henderson@linaro.org>
To: qemu-devel@nongnu.org
Cc: peter.maydell@linaro.org, laurent@vivier.eu, evgreen@chromium.org
Subject: [Qemu-devel] [PATCH 0/1] util/path: Do not cache all filenames at startup
Date: Tue, 16 Apr 2019 19:32:24 -1000	[thread overview]
Message-ID: <20190417053225.27505-1-richard.henderson@linaro.org> (raw)
Message-ID: <20190417053224.S4CwpOzMeFBlbJs2mWjFKBsf09QFPrlKGfKtQgDFxZg@z> (raw)

This is a third variant attempting to fix the problem of
the -L interp_prefix handling not coping well pointing to
a full chroot.

Previous versions include:
https://lists.gnu.org/archive/html/qemu-devel/2018-05/msg06592.html
https://lists.gnu.org/archive/html/qemu-devel/2018-05/msg07304.html

Both of the other versions keep an open file descriptor to
the directory that is interp_prefix.  While this seems to be
efficient, they also leak a file descriptor into the guest.
This has follow-on effects on the emulation, causing failures
e.g. within the LTP testsuite.

This version uses only string manipulation and access(2).

A plausible criticism of this is the mutex and the cache.
Are they really needed?  I have no idea.  I can imagine
removing that is actually more efficient, not needing a
lock around a shared data structure.

Comments?


r~


Richard Henderson (1):
  util/path: Do not cache all filenames at startup

 util/path.c | 211 ++++++++++++++--------------------------------------
 1 file changed, 57 insertions(+), 154 deletions(-)

-- 
2.17.1



             reply	other threads:[~2019-04-17  5:32 UTC|newest]

Thread overview: 16+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-04-17  5:32 Richard Henderson [this message]
2019-04-17  5:32 ` [Qemu-devel] [PATCH 0/1] util/path: Do not cache all filenames at startup Richard Henderson
2019-04-17  5:32 ` [Qemu-devel] [PATCH 1/1] " Richard Henderson
2019-04-17  5:32   ` Richard Henderson
2019-04-23  9:54   ` Philippe Mathieu-Daudé
2019-04-23  9:54     ` Philippe Mathieu-Daudé
2019-04-23 10:01     ` Daniel P. Berrangé
2019-04-23 10:01       ` Daniel P. Berrangé
2019-04-23 18:30       ` David Hildenbrand
2019-04-23 18:30         ` David Hildenbrand
2019-04-24  8:18         ` Daniel P. Berrangé
2019-04-24  8:18           ` Daniel P. Berrangé
2019-04-17  5:39 ` [Qemu-devel] [PATCH 0/1] " no-reply
2019-04-17  5:39   ` no-reply
2019-04-17  5:40 ` no-reply
2019-04-17  5:40   ` no-reply

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