diff options
| author | Brian Behlendorf <[email protected]> | 2015-12-02 11:53:37 -0800 |
|---|---|---|
| committer | Brian Behlendorf <[email protected]> | 2015-12-07 12:20:43 -0800 |
| commit | b58986eebf3c47c946393da4b968ee33edaea99e (patch) | |
| tree | 6104d36d9f2fd55a4725090f1b5098b4d1272103 /config | |
| parent | f40926795c1a1d3750e2a6f6904061cfa68715df (diff) | |
Use large stacks when available
While stack size will vary by architecture it has historically defaulted to
8K on x86_64 systems. However, as of Linux 3.15 the default thread stack
size was increased to 16K. These kernels are now the default in most non-
enterprise distributions which means we no longer need to assume 8K stacks.
This patch takes advantage of that fact by appropriately reverting stack
conservation changes which were made to ensure stability. Changes which
may have had a negative impact on performance for certain workloads. This
also has the side effect of bringing the code slightly more in line with
upstream.
Signed-off-by: Brian Behlendorf <[email protected]>
Signed-off-by: Richard Yao <[email protected]>
Closes #4059
Diffstat (limited to 'config')
| -rw-r--r-- | config/Rules.am | 3 | ||||
| -rw-r--r-- | config/kernel.m4 | 28 |
2 files changed, 29 insertions, 2 deletions
diff --git a/config/Rules.am b/config/Rules.am index af20ddb39..20a21e972 100644 --- a/config/Rules.am +++ b/config/Rules.am @@ -7,7 +7,8 @@ AM_CFLAGS += ${NO_BOOL_COMPARE} AM_CFLAGS += -fno-strict-aliasing AM_CPPFLAGS = -D_GNU_SOURCE -D__EXTENSIONS__ -D_REENTRANT AM_CPPFLAGS += -D_POSIX_PTHREAD_SEMANTICS -D_FILE_OFFSET_BITS=64 -AM_CPPFLAGS += -D_LARGEFILE64_SOURCE -DTEXT_DOMAIN=\"zfs-linux-user\" +AM_CPPFLAGS += -D_LARGEFILE64_SOURCE -DHAVE_LARGE_STACKS=1 +AM_CPPFLAGS += -DTEXT_DOMAIN=\"zfs-linux-user\" AM_CPPFLAGS += -DLIBEXECDIR=\"$(libexecdir)\" AM_CPPFLAGS += -DRUNSTATEDIR=\"$(runstatedir)\" AM_CPPFLAGS += -DSBINDIR=\"$(sbindir)\" diff --git a/config/kernel.m4 b/config/kernel.m4 index 0a65f39ef..906d39d59 100644 --- a/config/kernel.m4 +++ b/config/kernel.m4 @@ -460,10 +460,36 @@ AC_DEFUN([ZFS_AC_KERNEL_CONFIG], [ ], [ ]) + ZFS_AC_KERNEL_CONFIG_THREAD_SIZE ZFS_AC_KERNEL_CONFIG_DEBUG_LOCK_ALLOC ]) dnl # +dnl # Check configured THREAD_SIZE +dnl # +dnl # The stack size will vary by architecture, but as of Linux 3.15 on x86_64 +dnl # the default thread stack size was increased to 16K from 8K. Therefore, +dnl # on newer kernels and some architectures stack usage optimizations can be +dnl # conditionally applied to improve performance without negatively impacting +dnl # stability. +dnl # +AC_DEFUN([ZFS_AC_KERNEL_CONFIG_THREAD_SIZE], [ + AC_MSG_CHECKING([whether kernel was built with 16K or larger stacks]) + ZFS_LINUX_TRY_COMPILE([ + #include <linux/module.h> + ],[ + #if (THREAD_SIZE < 16384) + #error "THREAD_SIZE is less than 16K" + #endif + ],[ + AC_MSG_RESULT([yes]) + AC_DEFINE(HAVE_LARGE_STACKS, 1, [kernel has large stacks]) + ],[ + AC_MSG_RESULT([no]) + ]) +]) + +dnl # dnl # Check CONFIG_DEBUG_LOCK_ALLOC dnl # dnl # This is typically only set for debug kernels because it comes with @@ -572,7 +598,7 @@ dnl # dnl # ZFS_LINUX_CONFIG dnl # AC_DEFUN([ZFS_LINUX_CONFIG], - [AC_MSG_CHECKING([whether Linux was built with CONFIG_$1]) + [AC_MSG_CHECKING([whether kernel was built with CONFIG_$1]) ZFS_LINUX_TRY_COMPILE([ #include <linux/module.h> ],[ |