powerpc/pseries: Add kernel parameter to disable batched hcalls

This introduces a pair of kernel parameters that can be used to disable
the MULTITCE and BULK_REMOVE h-calls.

By default, those hcalls are enabled, active, and good for throughput
and performance.  The ability to disable them will be useful for some of
the PREEMPT_RT related investigation and work occurring on Power.

Signed-off-by: Will Schmidt <will_schmidt@vnet.ibm.com>
cc: Olof Johansson <olof@lixom.net>
cc: Anton Blanchard <anton@samba.org>
cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
This commit is contained in:
Will Schmidt 2010-09-28 15:33:12 +00:00 committed by Benjamin Herrenschmidt
parent 475fc7c011
commit 4e89a2d8e2
3 changed files with 34 additions and 0 deletions

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@ -403,6 +403,10 @@ and is between 256 and 4096 characters. It is defined in the file
bttv.pll= See Documentation/video4linux/bttv/Insmod-options
bttv.tuner= and Documentation/video4linux/bttv/CARDLIST
bulk_remove=off [PPC] This parameter disables the use of the pSeries
firmware feature for flushing multiple hpte entries
at a time.
c101= [NET] Moxa C101 synchronous serial card
cachesize= [BUGS=X86-32] Override level 2 CPU cache size detection.
@ -1490,6 +1494,10 @@ and is between 256 and 4096 characters. It is defined in the file
mtdparts= [MTD]
See drivers/mtd/cmdlinepart.c.
multitce=off [PPC] This parameter disables the use of the pSeries
firmware feature for updating multiple TCE entries
at a time.
onenand.bdry= [HW,MTD] Flex-OneNAND Boundary Configuration
Format: [die0_boundary][,die0_lock][,die1_boundary][,die1_lock]

View File

@ -622,3 +622,17 @@ void iommu_init_early_pSeries(void)
set_pci_dma_ops(&dma_iommu_ops);
}
static int __init disable_multitce(char *str)
{
if (strcmp(str, "off") == 0 &&
firmware_has_feature(FW_FEATURE_LPAR) &&
firmware_has_feature(FW_FEATURE_MULTITCE)) {
printk(KERN_INFO "Disabling MULTITCE firmware feature\n");
ppc_md.tce_build = tce_build_pSeriesLP;
ppc_md.tce_free = tce_free_pSeriesLP;
powerpc_firmware_features &= ~FW_FEATURE_MULTITCE;
}
return 1;
}
__setup("multitce=", disable_multitce);

View File

@ -627,6 +627,18 @@ static void pSeries_lpar_flush_hash_range(unsigned long number, int local)
spin_unlock_irqrestore(&pSeries_lpar_tlbie_lock, flags);
}
static int __init disable_bulk_remove(char *str)
{
if (strcmp(str, "off") == 0 &&
firmware_has_feature(FW_FEATURE_BULK_REMOVE)) {
printk(KERN_INFO "Disabling BULK_REMOVE firmware feature");
powerpc_firmware_features &= ~FW_FEATURE_BULK_REMOVE;
}
return 1;
}
__setup("bulk_remove=", disable_bulk_remove);
void __init hpte_init_lpar(void)
{
ppc_md.hpte_invalidate = pSeries_lpar_hpte_invalidate;