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2010-10-13ioat2: fix performance regressionDan Williams
Commit 0793448 "DMAENGINE: generic channel status v2" changed the interface for how dma channel progress is retrieved. It inadvertently exported an internal helper function ioat_tx_status() instead of ioat_dma_tx_status(). The latter polls the hardware to get the latest completion state, while the helper just evaluates the current state without touching hardware. The effect is that we end up waiting for completion timeouts or descriptor allocation errors before the completion state is updated. iperf (before fix): [SUM] 0.0-41.3 sec 364 MBytes 73.9 Mbits/sec iperf (after fix): [SUM] 0.0- 4.5 sec 499 MBytes 940 Mbits/sec This is a regression starting with 2.6.35. Cc: <stable@kernel.org> Cc: Dave Jiang <dave.jiang@intel.com> Cc: Jesse Brandeburg <jesse.brandeburg@intel.com> Cc: Linus Walleij <linus.walleij@stericsson.com> Cc: Maciej Sosnowski <maciej.sosnowski@intel.com> Reported-by: Richard Scobie <richard@sauce.co.nz> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2010-08-04ioat2: catch and recover from broken vtd configurations v6Dan Williams
On some platforms (MacPro3,1) the BIOS assigns the ioatdma device to the incorrect iommu causing faults when the driver initializes. Add a quirk to catch this misconfiguration and try falling back to untranslated operation (which works in the MacPro3,1 case). Assuming there are other platforms with misconfigured iommus teach the ioatdma driver to treat initialization failures as non-fatal (just fail the driver load and emit a warning instead of triggering a BUG_ON). This can be classified as a boot regression since 2.6.32 on affected platforms since the ioatdma module did not autoload prior to that kernel. Cc: <stable@kernel.org> Acked-by: David Woodhouse <David.Woodhouse@intel.com> Reported-by: Chris Li <lkml@chrisli.org> Tested-by: Chris Li <lkml@chrisli.org> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2010-05-17Merge branch 'ioat' into dmaengineDan Williams
2010-05-02ioat: Remove duplicated devm_kzalloc() calls for ioatdma_deviceMinskey Guo
The memory for ioatdma_device structure is being allocated in alloc_ioatdma() Signed-off-by: Minskey Guo <chaohong_guo@linux.intel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2010-05-01ioat3: disable cacheline-unaligned transfers for raid operationsDan Williams
There are cases where cacheline-unaligned raid operations can hang the dma channel. Simply disable these operations by increasing the alignment constraints published to async_tx. The raid456 driver always issues page aligned requests, so the only in-kernel user of the ioatdma driver that is affected by this change is dmatest. Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2010-05-01ioat2,3: convert to producer/consumer lockingDan Williams
Use separate locks for the descriptor prep (producer) and descriptor cleanup (consumer) paths. Allows the producer path to run concurrently with the cleanup path. Inspired by Documentation/circular-buffer.txt. Cc: David Howells <dhowells@redhat.com> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Maciej Sosnowski <maciej.sosnowski@intel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2010-05-01ioat: convert to circ_bufDan Williams
Use the common power-of-2 circular buffer macros. Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2010-03-30include cleanup: Update gfp.h and slab.h includes to prepare for breaking ↵Tejun Heo
implicit slab.h inclusion from percpu.h percpu.h is included by sched.h and module.h and thus ends up being included when building most .c files. percpu.h includes slab.h which in turn includes gfp.h making everything defined by the two files universally available and complicating inclusion dependencies. percpu.h -> slab.h dependency is about to be removed. Prepare for this change by updating users of gfp and slab facilities include those headers directly instead of assuming availability. As this conversion needs to touch large number of source files, the following script is used as the basis of conversion. http://userweb.kernel.org/~tj/misc/slabh-sweep.py The script does the followings. * Scan files for gfp and slab usages and update includes such that only the necessary includes are there. ie. if only gfp is used, gfp.h, if slab is used, slab.h. * When the script inserts a new include, it looks at the include blocks and try to put the new include such that its order conforms to its surrounding. It's put in the include block which contains core kernel includes, in the same order that the rest are ordered - alphabetical, Christmas tree, rev-Xmas-tree or at the end if there doesn't seem to be any matching order. * If the script can't find a place to put a new include (mostly because the file doesn't have fitting include block), it prints out an error message indicating which .h file needs to be added to the file. The conversion was done in the following steps. 1. The initial automatic conversion of all .c files updated slightly over 4000 files, deleting around 700 includes and adding ~480 gfp.h and ~3000 slab.h inclusions. The script emitted errors for ~400 files. 2. Each error was manually checked. Some didn't need the inclusion, some needed manual addition while adding it to implementation .h or embedding .c file was more appropriate for others. This step added inclusions to around 150 files. 3. The script was run again and the output was compared to the edits from #2 to make sure no file was left behind. 4. Several build tests were done and a couple of problems were fixed. e.g. lib/decompress_*.c used malloc/free() wrappers around slab APIs requiring slab.h to be added manually. 5. The script was run on all .h files but without automatically editing them as sprinkling gfp.h and slab.h inclusions around .h files could easily lead to inclusion dependency hell. Most gfp.h inclusion directives were ignored as stuff from gfp.h was usually wildly available and often used in preprocessor macros. Each slab.h inclusion directive was examined and added manually as necessary. 6. percpu.h was updated not to include slab.h. 7. Build test were done on the following configurations and failures were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my distributed build env didn't work with gcov compiles) and a few more options had to be turned off depending on archs to make things build (like ipr on powerpc/64 which failed due to missing writeq). * x86 and x86_64 UP and SMP allmodconfig and a custom test config. * powerpc and powerpc64 SMP allmodconfig * sparc and sparc64 SMP allmodconfig * ia64 SMP allmodconfig * s390 SMP allmodconfig * alpha SMP allmodconfig * um on x86_64 SMP allmodconfig 8. percpu.h modifications were reverted so that it could be applied as a separate patch and serve as bisection point. Given the fact that I had only a couple of failures from tests on step 6, I'm fairly confident about the coverage of this conversion patch. If there is a breakage, it's likely to be something in one of the arch headers which should be easily discoverable easily on most builds of the specific arch. Signed-off-by: Tejun Heo <tj@kernel.org> Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
2010-03-26dmaengine: provide helper for setting txstateDan Williams
Simple conditional struct filler to cut out some duplicated code. Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2010-03-26DMAENGINE: generic channel status v2Linus Walleij
Convert the device_is_tx_complete() operation on the DMA engine to a generic device_tx_status()operation which can return three states, DMA_TX_RUNNING, DMA_TX_COMPLETE, DMA_TX_PAUSED. [dan.j.williams@intel.com: update for timberdale] Signed-off-by: Linus Walleij <linus.walleij@stericsson.com> Acked-by: Mark Brown <broonie@opensource.wolfsonmicro.com> Cc: Maciej Sosnowski <maciej.sosnowski@intel.com> Cc: Nicolas Ferre <nicolas.ferre@atmel.com> Cc: Pavel Machek <pavel@ucw.cz> Cc: Li Yang <leoli@freescale.com> Cc: Guennadi Liakhovetski <g.liakhovetski@gmx.de> Cc: Paul Mundt <lethal@linux-sh.org> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Haavard Skinnemoen <haavard.skinnemoen@atmel.com> Cc: Magnus Damm <damm@opensource.se> Cc: Liam Girdwood <lrg@slimlogic.co.uk> Cc: Joe Perches <joe@perches.com> Cc: Roland Dreier <rdreier@cisco.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2010-03-07Driver core: Constify struct sysfs_ops in struct kobj_typeEmese Revfy
Constify struct sysfs_ops. This is part of the ops structure constification effort started by Arjan van de Ven et al. Benefits of this constification: * prevents modification of data that is shared (referenced) by many other structure instances at runtime * detects/prevents accidental (but not intentional) modification attempts on archs that enforce read-only kernel data at runtime * potentially better optimized code as the compiler can assume that the const data cannot be changed * the compiler/linker move const data into .rodata and therefore exclude them from false sharing Signed-off-by: Emese Revfy <re.emese@gmail.com> Acked-by: David Teigland <teigland@redhat.com> Acked-by: Matt Domsch <Matt_Domsch@dell.com> Acked-by: Maciej Sosnowski <maciej.sosnowski@intel.com> Acked-by: Hans J. Koch <hjk@linutronix.de> Acked-by: Pekka Enberg <penberg@cs.helsinki.fi> Acked-by: Jens Axboe <jens.axboe@oracle.com> Acked-by: Stephen Hemminger <shemminger@vyatta.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-03-06bitops: rename for_each_bit() to for_each_set_bit()Akinobu Mita
Rename for_each_bit to for_each_set_bit in the kernel source tree. To permit for_each_clear_bit(), should that ever be added. The patch includes a macro to map the old for_each_bit() onto the new for_each_set_bit(). This is a (very) temporary thing to ease the migration. [akpm@linux-foundation.org: add temporary for_each_bit()] Suggested-by: Alexey Dobriyan <adobriyan@gmail.com> Suggested-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com> Cc: "David S. Miller" <davem@davemloft.net> Cc: Russell King <rmk@arm.linux.org.uk> Cc: David Woodhouse <dwmw2@infradead.org> Cc: Artem Bityutskiy <dedekind@infradead.org> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-03-03Merge branch 'coh' into dmaengineDan Williams
2010-03-03ioat: cleanup ->timer_fn() and ->cleanup_fn() prototypesDan Williams
If the calling convention of ->timer_fn() and ->cleanup_fn() are unified across hardware versions we can drop parameters to ioat_init_channel() and unify ioat_is_dma_complete() implementations. Both ->timer_fn() and ->cleanup_fn() are modified to expect a struct dma_chan pointer. Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2010-03-03ioat3: interrupt coalescingDan Williams
The hardware automatically disables further interrupts after each event until rearmed. This allows a delay to be injected between the occurence of the interrupt and the running of the cleanup routine. The delay is scaled by the descriptor backlog and then written to the INTRDELAY register which specifies the number of microseconds to hold off interrupt delivery after an interrupt event occurs. According to powertop this reduces the interrupt rate from ~5000 intr/s to ~150 intr/s per without affecting throughput (simple dd to a raid6 array). Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2010-03-03ioat: close potential BUG_ON race in the descriptor cleanup pathDan Williams
Since ioat_cleanup_preamble() and the update of the last completed descriptor are not synchronized there is a chance that two cleanup threads can see descriptors to clean. If the first cleans up all pending descriptors then the second will trigger the BUG_ON. Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2010-03-03ioat2: kill pending flagDan Williams
The pending == 2 case no longer exists in the driver so, we can use ioat2_ring_pending() outside the lock to determine if there might be any descriptors in the ring that the hardware has not seen. Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2010-03-03ioat3: use ioat2_quiesce()Dan Williams
Replace open coded ioat2_quiesce() call in ioat3_restart_channel Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2010-03-03ioat3: cleanup, don't enable DCA completion writesDan Williams
We already disallow raid operations while DCA is globally enabled, so having it locally enabled is a nop and confusing when reading the code. Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2010-02-02ioat: fix infinite timeout checking in ioat2_quiesceDan Williams
Fix typo in ioat2_quiesce. check 'tmo' is zero, not 'end'. Also applies to 2.6.32.3 Cc: <stable@kernel.org> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2009-12-19ioat2,3: put channel hardware in known state at initDan Williams
Put the ioat2 and ioat3 state machines in the halted state with all errors cleared. The ioat1 init path is not disturbed for stability, there are no reported ioat1 initiaization issues. Cc: <stable@kernel.org> Reported-by: Roland Dreier <rdreier@cisco.com> Tested-by: Roland Dreier <rdreier@cisco.com> Acked-by: Simon Horman <horms@verge.net.au> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2009-12-17ioat3: fix p-disabled q-continuationDan Williams
When continuing a pq calculation the driver needs 3 extra sources. The driver can perform a 3 source calculation with a single descriptor, but needs an extended descriptor to process up to 8 sources in one operation. However, in the p-disabled case only one extra source is needed. When continuing a p-disabled operation there are occasions (i.e. 0 < src_cnt % 8 < 3) where the tail operation does not need an extended descriptor. Properly account for this fact otherwise invalid 'dmacount' values will be written to hardware usually causing the channel to halt with 'invalid descriptor' errors. Cc: <stable@kernel.org> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2009-11-19ioat3: fix pq completion versus channel deallocation raceDan Williams
The completion of a pq operation is notified with a null descriptor appended to the end of the chain. This descriptor needs to be visible to dma clients otherwise the client is precluded from ensuring all operations are quiesced before freeing channel resources, i.e. due to descriptor polling it may get the completion notification ahead of the interrupt delivered by the null descriptor. Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2009-11-19async_tx: build-time toggling of async_{syndrome,xor}_val dma supportDan Williams
ioat3.2 does not support asynchronous error notifications which makes the driver experience latencies when non-zero pq validate results are expected. Provide a mechanism for turning off async_xor_val and async_syndrome_val via Kconfig. This approach is generally useful for any driver that specifies ASYNC_TX_DISABLE_CHANNEL_SWITCH and would like to force the async_tx api to fall back to the synchronous path for certain operations. Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2009-11-19ioat2,3: report all uncorrectable errorsDan Williams
Modify is_ioat_bug() to catch all errors that are uncorrectable, or not currently handled. Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2009-11-19ioat3: specify valid address for disabled-Q or disabled-PDan Williams
Although disabled, hardware still checks address validity, so duplicate the known address. Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2009-11-19ioat2,3: disable asynchronous error notificationsDan Williams
Error interrupts and error completions may cause channel hangs, so poll the channel status register after a timeout. Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2009-11-19ioat3: dca and raid operations are incompatibleDan Williams
RAID operations cause a system hang on platforms with DCA (Direct-Cache-Access) enabled. So turn off RAID capabilities in this case. Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2009-11-17ioat: silence "dca disabled" messagesDan Williams
Turning off dca is not an "error", and the dca-enabled state can be viewed from sysfs. Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2009-09-21ioat3: fix uninitialized var warningsDan Williams
drivers/dma/ioat/dma_v3.c: In function 'ioat3_prep_memset_lock': drivers/dma/ioat/dma_v3.c:439: warning: 'fill' may be used uninitialized in this function drivers/dma/ioat/dma_v3.c:437: warning: 'desc' may be used uninitialized in this function drivers/dma/ioat/dma_v3.c: In function '__ioat3_prep_xor_lock': drivers/dma/ioat/dma_v3.c:489: warning: 'xor' may be used uninitialized in this function drivers/dma/ioat/dma_v3.c:486: warning: 'desc' may be used uninitialized in this function drivers/dma/ioat/dma_v3.c: In function '__ioat3_prep_pq_lock': drivers/dma/ioat/dma_v3.c:631: warning: 'pq' may be used uninitialized in this function drivers/dma/ioat/dma_v3.c:628: warning: 'desc' may be used uninitialized in this function gcc-4.0, unlike gcc-4.3, does not see that these variables are initialized before use. Convert the descriptor loops to do-while make this initialization apparent. Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2009-09-21drivers/dma/ioat/dma_v2.c: fix warningsAndrew Morton
drivers/dma/ioat/dma_v2.c: In function 'ioat2_dma_prep_memcpy_lock': drivers/dma/ioat/dma_v2.c:680: warning: 'hw' may be used uninitialized in this function drivers/dma/ioat/dma_v2.c:681: warning: 'desc' may be used uninitialized in this function Cc: Maciej Sosnowski <maciej.sosnowski@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2009-09-16ioat2: clarify ring size limitsDan Williams
With the addition of ioat_max_alloc_order it is not clear what the maximum allocation order is, so document that in the modinfo. Also take an opportunity to kill a stray semicolon. Signed-off-by: Maciej Sosnowski <maciej.sosnowski@intel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2009-09-10ioat: driver version 4.0Dan Williams
A new ring implementation and the addition of raid functionality constitutes a bump in the driver major version number. Signed-off-by: Maciej Sosnowski <maciej.sosnowski@intel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2009-09-10dca: registering requesters in multiple dca domainsMaciej Sosnowski
This patch enables DCA support on multiple-IOH/multiple-IIO architectures. It modifies dca module by replacing single dca_providers list with dca_domains list, each domain containing separate list of providers. This approach lets dca driver manage multiple domains, i.e. sets of providers and requesters mapped back to the same PCI root complex device. The driver takes care to register each requester to a provider from the same domain. Signed-off-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Maciej Sosnowski <maciej.sosnowski@intel.com>
2009-09-08Merge branch 'dmaengine' into async-tx-nextDan Williams
Conflicts: crypto/async_tx/async_xor.c drivers/dma/ioat/dma_v2.h drivers/dma/ioat/pci.c drivers/md/raid5.c
2009-09-08ioat2,3: cacheline align software descriptor allocationsDan Williams
All the necessary fields for handling an ioat2,3 ring entry can fit into one cacheline. Move ->len prior to ->txd in struct ioat_ring_ent, and move allocation of these entries to a hw-cache-aligned kmem cache to reduce the number of cachelines dirtied for descriptor management. Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2009-09-08ioat: implement a private tx_listDan Williams
Drop ioatdma's use of tx_list from struct dma_async_tx_descriptor in preparation for removal of this field. Cc: Maciej Sosnowski <maciej.sosnowski@intel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2009-09-08I/OAT: Convert to PCI_VDEVICE()Roland Dreier
Trivial cleanup to make the PCI ID table easier to read. [dan.j.williams@intel.com: extended to v3.2 devices] Signed-off-by: Roland Dreier <rolandd@cisco.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2009-09-08Add MODULE_DEVICE_TABLE() so ioatdma module is autoloadedRoland Dreier
The ioatdma module is missing aliases for the PCI devices it supports, so it is not autoloaded on boot. Add a MODULE_DEVICE_TABLE() to get these aliases. Signed-off-by: Roland Dreier <rolandd@cisco.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2009-09-08ioat3: segregate raid enginesDan Williams
The cleanup routine for the raid cases imposes extra checks for handling raid descriptors and extended descriptors. If the channel does not support raid it can avoid this extra overhead by using the ioat2 cleanup path. Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2009-09-08ioat3: ioat3.2 pci ids for Jasper ForestTom Picard
Jasper Forest introduces raid offload support via ioat3.2 support. When raid offload is enabled two (out of 8 channels) will report raid5/raid6 offload capabilities. The remaining channels will only report ioat3.0 capabilities (memcpy). Signed-off-by: Tom Picard <tom.s.picard@intel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2009-09-08ioat3: interrupt descriptor supportDan Williams
The async_tx api uses the DMA_INTERRUPT operation type to terminate a chain of issued operations with a callback routine. Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2009-09-08ioat3: support xor via pq descriptorsDan Williams
If a platform advertises pq capabilities, but not xor, then use ioat3_prep_pqxor and ioat3_prep_pqxor_val to simulate xor support. Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2009-09-08ioat3: pq supportDan Williams
ioat3.2 adds support for raid6 syndrome generation (xor sum of galois field multiplication products) using up to 8 sources. It can also perform an pq-zero-sum operation to validate whether the syndrome for a given set of sources matches a previously computed syndrome. Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2009-09-08ioat3: xor self testDan Williams
This adds a hardware specific self test to be called from ioat_probe. In the ioat3 case we will have tests for all the different raid operations, while ioat1 and ioat2 will continue to just test memcpy. Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2009-09-08ioat3: xor supportDan Williams
ioat3.2 adds xor offload support for up to 8 sources. It can also perform an xor-zero-sum operation to validate whether all given sources sum to zero, without writing to a destination. Xor descriptors differ from memcpy in that one operation may require multiple descriptors depending on the number of sources. When the number of sources exceeds 5 an extended descriptor is needed. These descriptors need to be accounted for when updating the DMA_COUNT register. Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2009-09-08ioat3: enable dca for completion writesDan Williams
Tag completion writes for direct cache access to reduce the latency of checking for descriptor completions. Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2009-09-08ioat: add 'ioat' sysfs attributesDan Williams
Export driver attributes for diagnostic purposes: 'ring_size': total number of descriptors available to the engine 'ring_active': number of descriptors in-flight 'capabilities': supported operation types for this channel 'version': Intel(R) QuickData specfication revision This also allows some chattiness to be removed from the driver startup as this information is now available via sysfs. Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2009-09-08ioat3: split ioat3 support to its own file, add memsetDan Williams
Up until this point the driver for Intel(R) QuickData Technology engines, specification versions 2 and 3, were mostly identical save for a few quirks. Version 3.2 hardware adds many new capabilities (like raid offload support) requiring some infrastructure that is not relevant for v2. For better code organization of the new funcionality move v3 and v3.2 support to its own file dma_v3.c, and export some routines from the base files (dma.c and dma_v2.c) that can be reused directly. The first new capability included in this code reorganization is support for v3.2 memset operations. Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2009-09-08ioat3: hardware version 3.2 register / descriptor definitionsDan Williams
ioat3.2 adds raid5 and raid6 offload capabilities. Signed-off-by: Tom Picard <tom.s.picard@intel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>