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| author | Kirill Smelkov <kirr@nexedi.com> | 2019-06-23 07:28:53 +0000 |
|---|---|---|
| committer | Masahiro Yamada <yamada.masahiro@socionext.com> | 2019-07-08 02:25:59 +0900 |
| commit | 0c4ab18fc33bba70299f51fac83e32397cf9a04b (patch) | |
| tree | 5be658bb4f5ec66d531fc68eb380c4601faa0abc /scripts/coccinelle | |
| parent | f58c17c202e7aec9623754a7ec0b0669e043b838 (diff) | |
| download | lwn-0c4ab18fc33bba70299f51fac83e32397cf9a04b.tar.gz lwn-0c4ab18fc33bba70299f51fac83e32397cf9a04b.zip | |
coccinelle: api/stream_open: treat all wait_.*() calls as blocking
Previously steam_open.cocci was treating only wait_event_.* - e.g.
wait_event_interruptible - as a blocking operation. However e.g.
wait_for_completion_interruptible is also blocking, and so from this
point of view it would be more logical to treat all wait_.* as a
blocking point.
The logic of this change actually came up for real when
drivers/pci/switch/switchtec.c changed from using
wait_event_interruptible to wait_for_completion_interruptible:
https://lore.kernel.org/linux-pci/20190413170056.GA11293@deco.navytux.spb.ru/
https://lore.kernel.org/linux-pci/20190415145456.GA15280@deco.navytux.spb.ru/
https://lore.kernel.org/linux-pci/20190415154102.GB17661@deco.navytux.spb.ru/
For a driver that uses nonseekable_open with read/write having stream
semantic and read also calling e.g. wait_for_completion_interruptible,
running stream_open.cocci before this patch would produce:
WARNING: <driver>_fops: .read() and .write() have stream semantic; safe to change nonseekable_open -> stream_open.
while after this patch it will report:
ERROR: <driver>_fops: .read() can deadlock .write(); change nonseekable_open -> stream_open to fix.
Signed-off-by: Kirill Smelkov <kirr@nexedi.com>
Acked-by: Julia Lawall <julia.lawall@lip6.fr>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Diffstat (limited to 'scripts/coccinelle')
| -rw-r--r-- | scripts/coccinelle/api/stream_open.cocci | 8 |
1 files changed, 4 insertions, 4 deletions
diff --git a/scripts/coccinelle/api/stream_open.cocci b/scripts/coccinelle/api/stream_open.cocci index 350145da7669..12ce18fa6b74 100644 --- a/scripts/coccinelle/api/stream_open.cocci +++ b/scripts/coccinelle/api/stream_open.cocci @@ -35,11 +35,11 @@ type loff_t; // a function that blocks @ blocks @ identifier block_f; -identifier wait_event =~ "^wait_event_.*"; +identifier wait =~ "^wait_.*"; @@ block_f(...) { ... when exists - wait_event(...) + wait(...) ... when exists } @@ -49,12 +49,12 @@ identifier wait_event =~ "^wait_event_.*"; // XXX currently reader_blocks supports only direct and 1-level indirect cases. @ reader_blocks_direct @ identifier stream_reader.readstream; -identifier wait_event =~ "^wait_event_.*"; +identifier wait =~ "^wait_.*"; @@ readstream(...) { ... when exists - wait_event(...) + wait(...) ... when exists } |