| 2a4830110b90deb4ee99b1ab8c8ebb120f27c0c8 |
|
30-Dec-2011 |
Seth Jennings <sjenning@linux.vnet.ibm.com> |
staging: zcache: fix serialization bug in zv stats
In a multithreaded workload, the zv_curr_dist_counts
and zv_cumul_dist_counts statistics are being corrupted
because the increments and decrements in zv_create
and zv_free are not atomic.
This patch converts these statistics and their corresponding
increments/decrements/reads to atomic operations.
Signed-off-by: Seth Jennings <sjenning@linux.vnet.ibm.com>
Acked-by: Dan Magenheimer <dan.magenheimer@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
/drivers/staging/zcache/zcache-main.c
|
| e8b4553457e78bcff90f70a31212a40a8fd4f0db |
|
23-Jan-2012 |
Dan Magenheimer <dan.magenheimer@oracle.com> |
zcache: Set SWIZ_BITS to 8 to reduce tmem bucket lock contention.
SWIZ_BITS > 8 results in a much larger number of "tmem_obj"
allocations, likely one per page-placed-in-frontswap. The
tmem_obj is not huge (roughly 100 bytes), but it is large
enough to add a not-insignificant memory overhead to zcache.
The SWIZ_BITS=8 will get roughly the same lock contention
without the space wastage.
The effect of SWIZ_BITS can be thought of as "2^SWIZ_BITS is
the number of unique oids that be generated" (This concept is
limited to frontswap's use of tmem).
Acked-by: Seth Jennings <sjenning@linux.vnet.ibm.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
/drivers/staging/zcache/zcache-main.c
|
| 9256a4789be3dae37d00924c03546ba7958ea5a3 |
|
25-Jan-2012 |
Dan Magenheimer <dan.magenheimer@oracle.com> |
zcache: fix deadlock condition
I discovered this deadlock condition awhile ago working on RAMster
but it affects zcache as well. The list spinlock must be
locked prior to the page spinlock and released after. As
a result, the page copy must also be done while the locks are held.
Applies to 3.2. Konrad, please push (via GregKH?)...
this is definitely a bug fix so need not be pushed during
a -rc0 window.
Signed-off-by: Dan Magenheimer <dan.magenheimer@oracle.com>
Acked-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
/drivers/staging/zcache/zcache-main.c
|
| ebadb730435b74483daedcd59d664a2dccbe3903 |
|
23-Nov-2011 |
Bernhard Heinloth <bernhard@heinloth.net> |
Staging: zcache: Fix calls to obsolete function
Function "strict_strtol" replaced by "kstrtol" as suggested by the checkpatch script
Signed-off-by: Bernhard Heinloth <bernhard@heinloth.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
/drivers/staging/zcache/zcache-main.c
|
| 43a3beb6da994549ec28a9f31727b997a025f958 |
|
25-Oct-2011 |
Greg Kroah-Hartman <gregkh@suse.de> |
Merge branch 'staging-next' into Linux 3.1
This was done to resolve a conflict in the
drivers/staging/comedi/drivers/ni_labpc.c file that resolved a build
bugfix in Linus's tree with a "better" bugfix that was in the
staging-next tree that resolved the issue in a more complete manner.
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
|
| 00bf256011d362e7d61824f3cda8514f5d48585d |
|
12-Oct-2011 |
Seth Jennings <sjenning@linux.vnet.ibm.com> |
staging: zcache: remove zcache_direct_reclaim_lock
zcache_do_preload() currently does a spin_trylock() on the
zcache_direct_reclaim_lock. Holding this lock intends to prevent
shrink_zcache_memory() from evicting zbud pages as a result
of a preload.
However, it also prevents two threads from
executing zcache_do_preload() at the same time. The first
thread will obtain the lock and the second thread's spin_trylock()
will fail (an aborted preload) causing the page to be either lost
(cleancache) or pushed out to the swap device (frontswap). It
also doesn't ensure that the call to shrink_zcache_memory() is
on the same thread as the call to zcache_do_preload().
Additional, there is no need for this mechanism because all
zcache_do_preload() calls that come down from cleancache already
have PF_MEMALLOC set in the process flags which prevents
direct reclaim in the memory manager. If the zcache_do_preload()
call is done from the frontswap path, we _want_ reclaim to be
done (which it isn't right now).
This patch removes the zcache_direct_reclaim_lock and related
statistics in zcache.
Based on v3.1-rc8
Signed-off-by: Seth Jennings <sjenning@linux.vnet.ibm.com>
Reviewed-by: Dave Hansen <dave@linux.vnet.ibm.com>
Acked-by: Dan Magenheimer <dan.magenheimer@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
/drivers/staging/zcache/zcache-main.c
|
| 3d65c85f9187d311dbf1bf9e7fc2f5091a770853 |
|
04-Oct-2011 |
Seth Jennings <sjenning@linux.vnet.ibm.com> |
staging: zcache: reduce tmem bucket lock contention
tmem uses hash buckets each with their own rbtree and lock to
quickly lookup tmem objects. tmem has TMEM_HASH_BUCKETS (256)
buckets per pool. However, because of the way the tmem_oid is
generated for frontswap pages, only 16 unique tmem_oids are being
generated, resulting in only 16 of the 256 buckets being used.
This cause high lock contention for the per bucket locks.
This patch changes SWIZ_BITS to include more bits of the offset.
The result is that all 256 hash buckets are potentially used resulting in a
95% drop in hash bucket lock contention.
Signed-off-by: Seth Jennings <sjenning@linux.vnet.ibm.com>
Acked-by: Dan Magenheimer <dan.magenheimer@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
/drivers/staging/zcache/zcache-main.c
|
| 8550be08cbed164a8357491cc2c27cb99282b7ff |
|
06-Oct-2011 |
Seth Jennings <sjenning@linux.vnet.ibm.com> |
staging: zcache: fix crash on cpu remove
In the case that a cpu is taken offline before zcache_do_preload() is
ever called on the cpu, the per-cpu zcache_preloads structure will
be uninitialized. In the CPU_DEAD case for zcache_cpu_notifier(),
kp->obj is not checked before calling kmem_cache_free() on it.
If it is NULL, a crash results.
This patch ensures that both kp->obj and kp->page are not NULL before
calling the respective free functions. In practice, just checking
one or the other should be sufficient since they are assigned together
in zcache_do_preload(), but I check both for safety.
Signed-off-by: Seth Jennings <sjenning@linux.vnet.ibm.com>
Acked-by: Dave Hansen <dave@linux.vnet.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
/drivers/staging/zcache/zcache-main.c
|
| 80976804f501303a34a76e925119393722596dca |
|
20-Sep-2011 |
Seth Jennings <sjenning@linux.vnet.ibm.com> |
staging: zcache: fix cleancache crash
After commit c5f5c4db3938 ("staging: zcache: fix crash on high memory
swap") cleancache crashes on the first successful get. This was caused
by a remaining virt_to_page() call in zcache_pampd_get_data_and_free()
that only gets run in the cleancache path.
The patch converts the virt_to_page() to struct page casting like was
done for other instances in c5f5c4db3938.
Signed-off-by: Seth Jennings <sjenning@linux.vnet.ibm.com>
Tested-By: Valdis Kletnieks <valdis.kletnieks@vt.edu>
Acked-by: Dan Magenheimer <dan.magenheimer@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
/drivers/staging/zcache/zcache-main.c
|
| 6eafa4604cfa109a89524d35d93df11c37bd66b0 |
|
29-Aug-2011 |
Greg Kroah-Hartman <gregkh@suse.de> |
Merge 3.1-rc4 into staging-next
This resolves a conflict with:
drivers/staging/brcm80211/brcmsmac/types.h
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
|
| c5f5c4db393837ebb2ae47bf061d70e498f48f8c |
|
10-Aug-2011 |
Seth Jennings <sjenning@linux.vnet.ibm.com> |
staging: zcache: fix crash on high memory swap
zcache_put_page() was modified to pass page_address(page) instead of the
actual page structure. In combination with the function signature changes
to tmem_put() and zcache_pampd_create(), zcache_pampd_create() tries to
(re)derive the page structure from the virtual address. However, if the
original page is a high memory page (or any unmapped page), this
virt_to_page() fails because the page_address() in zcache_put_page()
returned NULL.
This patch changes zcache_put_page() and zcache_get_page() to pass
the page structure instead of the page's virtual address, which
may or may not exist.
Signed-off-by: Seth Jennings <sjenning@linux.vnet.ibm.com>
Acked-by: Dan Magenheimer <dan.magenheimer@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
/drivers/staging/zcache/zcache-main.c
|
| 0428fec32c5fde013cb8223c248972941b18ca59 |
|
22-Aug-2011 |
Seth Jennings <sjenning@linux.vnet.ibm.com> |
staging: zcache: fix typos
The patch fixes two typos in zcache-main.c
Signed-off-by: Seth Jennings <sjenning@linux.vnet.ibm.com>
Acked-by: Dan Magenheimer <dan.magenheimer@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
/drivers/staging/zcache/zcache-main.c
|
| dbe82eb1170c0095e0ce89676235e0b27d7040d1 |
|
22-Aug-2011 |
Seth Jennings <sjenning@linux.vnet.ibm.com> |
staging: zcache: fix possible sleep under lock
zcache_new_pool() calls kmalloc() with GFP_KERNEL which has
__GFP_WAIT set. However, zcache_new_pool() gets called on
a stack that holds the swap_lock spinlock, leading to a
possible sleep-with-lock situation. The lock is obtained
in enable_swap_info().
The patch replaces GFP_KERNEL with GFP_ATOMIC.
v2: replace with GFP_ATOMIC, not GFP_IOFS
Signed-off-by: Seth Jennings <sjenning@linux.vnet.ibm.com>
Acked-by: Dan Magenheimer <dan.magenheimer@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
/drivers/staging/zcache/zcache-main.c
|
| d8c778fdf2bcd42e495ca1ca67bca729639352b7 |
|
05-Aug-2011 |
Nitin Gupta <ngupta@vflare.org> |
zcache: Fix build error when sysfs is not defined
Signed-off-by: Nitin Gupta <ngupta@vflare.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
/drivers/staging/zcache/zcache-main.c
|
| 3ca15c4486beb113700cda44e32109cf0d97528b |
|
05-Aug-2011 |
Thadeu Lima de Souza Cascardo <cascardo@holoscopio.com> |
zcache: Use div_u64 for 64-bit division
xv_get_total_size_bytes returns a u64 value and it's used in a division.
This causes build failures in 32-bit architectures, as reported by Randy
Dunlap.
Reported-by: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@holoscopio.com>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Dan Magenheimer <dan.magenheimer@oracle.com>
Cc: Nitin Gupta <ngupta@vflare.org>
Acked-by: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
/drivers/staging/zcache/zcache-main.c
|
| 12623f07b9d01bbaf3035284ea6a110787cc1e66 |
|
03-Aug-2011 |
Thadeu Lima de Souza Cascardo <cascardo@holoscopio.com> |
staging: zcache: include module.h for MODULE_LICENSE
The oncoming cleanup of module.h usage requires the explicit inclusion
of module.h when it was otherwise being included indirectly. Otherwise,
building zcache will fail.
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@holoscopio.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
/drivers/staging/zcache/zcache-main.c
|
| fd6b68bbac9f100c8728b2cfe4e34f03f3df4e4d |
|
02-Aug-2011 |
Thadeu Lima de Souza Cascardo <cascardo@holoscopio.com> |
staging: zcache: module is GPL
This avoids tainting the kernel as if a proprietary module was loaded.
The kernel will still be tainted because this is a staging driver.
Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@holoscopio.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
/drivers/staging/zcache/zcache-main.c
|
| bf0c0259c79b325fd4ea139f363366d319786ea2 |
|
02-Aug-2011 |
Thadeu Lima de Souza Cascardo <cascardo@holoscopio.com> |
staging: fix zcache building
zcache is only building tmem.c and not building zcache.c. To keep the
module name, zcache.c must be renamed if symbols from tmem.c are to
remain unexported.
Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@holoscopio.com>
Acked-by: Dan Magenheimer <dan.magenheimer@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
/drivers/staging/zcache/zcache-main.c
|