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| author | Takashi Yano <takashi.yano@nifty.ne.jp> | 2024-09-01 04:31:03 +0900 |
|---|---|---|
| committer | Takashi Yano <takashi.yano@nifty.ne.jp> | 2024-09-02 20:12:39 +0900 |
| commit | f78009cb1ccf84cc343cf2441c76196461d87532 (patch) | |
| tree | 0a06dbdcfbfb32abf90bf92ef3f3df74dfd2d99c | |
| parent | 84d77e5918e18170c393407d477140fcf5d3e432 (diff) | |
| download | newlib-f78009cb1ccf84cc343cf2441c76196461d87532.zip newlib-f78009cb1ccf84cc343cf2441c76196461d87532.tar.gz newlib-f78009cb1ccf84cc343cf2441c76196461d87532.tar.bz2 | |
Cygwin: pipe: Fix a regression that raw_write() slows down
After the commit 7f3c22532577, writing to pipe extremely slows down.
This is because cygwait(select_sem, 10, cw_cancel) is called even
when write operation is already completed. With this patch, the
cygwait() is called only if the write operation is not completed.
Addresses: https://cygwin.com/pipermail/cygwin/2024-August/256398.html
Fixes: 7f3c22532577 ("Cygwin: pipe: handle signals explicitely in raw_write")
Reported-by: Jim Reisert AD1C <jjreisert@alum.mit.edu>
Reviewed-by: Corinna Vinschen <corinna@vinschen.de>
Signed-off-by: Takashi Yano <takashi.yano@nifty.ne.jp>
| -rw-r--r-- | winsup/cygwin/fhandler/pipe.cc | 6 | ||||
| -rw-r--r-- | winsup/cygwin/release/3.5.5 | 3 |
2 files changed, 7 insertions, 2 deletions
diff --git a/winsup/cygwin/fhandler/pipe.cc b/winsup/cygwin/fhandler/pipe.cc index 852076c..c686df6 100644 --- a/winsup/cygwin/fhandler/pipe.cc +++ b/winsup/cygwin/fhandler/pipe.cc @@ -518,8 +518,9 @@ fhandler_pipe_fifo::raw_write (const void *ptr, size_t len) raise (SIGPIPE); goto out; } - else - cygwait (select_sem, 10, cw_cancel); + /* Break out on completion */ + if (waitret == WAIT_OBJECT_0) + break; /* If we got a timeout in the blocking case, and we already did a short write, we got a signal in the previous loop. */ if (waitret == WAIT_TIMEOUT && short_write_once) @@ -527,6 +528,7 @@ fhandler_pipe_fifo::raw_write (const void *ptr, size_t len) waitret = WAIT_SIGNALED; break; } + cygwait (select_sem, 10, cw_cancel); } /* Loop in case of blocking write or SA_RESTART */ while (waitret == WAIT_TIMEOUT || waitret == WAIT_SIGNALED); diff --git a/winsup/cygwin/release/3.5.5 b/winsup/cygwin/release/3.5.5 index a98687c..904119a 100644 --- a/winsup/cygwin/release/3.5.5 +++ b/winsup/cygwin/release/3.5.5 @@ -4,3 +4,6 @@ Fixes: - Fix undesired behaviour of console master thread in win32-input-mode which is supported by Windows Termainal. Addresses: https://cygwin.com/pipermail/cygwin/2024-August/256380.html + +- Fix a regression in 3.5.4 that writing to pipe extremely slows down. + Addresses: https://cygwin.com/pipermail/cygwin/2024-August/256398.html |