2a4419b5b2
fs: fs_struct rwlock to spinlock struct fs_struct.lock is an rwlock with the read-side used to protect root and pwd members while taking references to them. Taking a reference to a path typically requires just 2 atomic ops, so the critical section is very small. Parallel read-side operations would have cacheline contention on the lock, the dentry, and the vfsmount cachelines, so the rwlock is unlikely to ever give a real parallelism increase. Replace it with a spinlock to avoid one or two atomic operations in typical path lookup fastpath. Signed-off-by: Nick Piggin <npiggin@kernel.dk> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> |
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| .. | ||
| adis16255 | ||
| asus_oled | ||
| batman-adv | ||
| comedi | ||
| crystalhd | ||
| cx25821 | ||
| cxt1e1 | ||
| dream | ||
| dt3155v4l | ||
| easycap | ||
| echo | ||
| et131x | ||
| frontier | ||
| go7007 | ||
| hv | ||
| iio | ||
| line6 | ||
| lirc | ||
| memrar | ||
| mrst-touchscreen | ||
| msm | ||
| octeon | ||
| otus | ||
| panel | ||
| phison | ||
| pohmelfs | ||
| quatech_usb2 | ||
| quickstart | ||
| rt2860 | ||
| rt2870 | ||
| rtl8187se | ||
| rtl8192e | ||
| rtl8192su | ||
| rtl8192u | ||
| samsung-laptop | ||
| sep | ||
| serqt_usb2 | ||
| slicoss | ||
| sm7xx | ||
| solo6x10 | ||
| spectra | ||
| ti-st | ||
| tidspbridge | ||
| tm6000 | ||
| udlfb | ||
| usbip | ||
| vme | ||
| vt6655 | ||
| vt6656 | ||
| winbond | ||
| wlags49_h2 | ||
| wlags49_h25 | ||
| wlan-ng | ||
| xgifb | ||
| zram | ||
| Kconfig | ||
| Makefile | ||
| staging.c | ||