Hi Michael, Minor comment inline.
On 09/18/2014 11:26 AM, Michael Neuling wrote: > From: Ian Munsie <imun...@au1.ibm.com> > > Currently msi_bitmap_alloc_hwirqs() will round up any IRQ allocation requests > to the nearest power of 2. eg. ask for 5 IRQs and you'll get 8. This wastes > a > lot of IRQs which can be a scarce resource. > > For cxl we can require multiple IRQs for every contexts that is attached to > the > accelerator. For AFU directed accelerators, there may be 1000s of contexts > attached, hence we can easily run out of IRQs, especially if we are needlessly > wasting them. > > This changes the msi_bitmap_alloc_hwirqs() to allocate only the required > number > of IRQs, hence avoiding this wastage. > > Signed-off-by: Ian Munsie <imun...@au1.ibm.com> > Signed-off-by: Michael Neuling <mi...@neuling.org> > --- > arch/powerpc/sysdev/msi_bitmap.c | 18 +++++++++++++----- > 1 file changed, 13 insertions(+), 5 deletions(-) > > diff --git a/arch/powerpc/sysdev/msi_bitmap.c > b/arch/powerpc/sysdev/msi_bitmap.c > index 2ff6302..e001559 100644 > --- a/arch/powerpc/sysdev/msi_bitmap.c > +++ b/arch/powerpc/sysdev/msi_bitmap.c > @@ -24,28 +24,36 @@ int msi_bitmap_alloc_hwirqs(struct msi_bitmap *bmp, int > num) > * This is fast, but stricter than we need. We might want to add > * a fallback routine which does a linear search with no alignment. > */ Is this comment still relevant (especially the part mentioning "fast")? --- Best Regards, Laurentiu _______________________________________________ Linuxppc-dev mailing list Linuxppc-dev@lists.ozlabs.org https://lists.ozlabs.org/listinfo/linuxppc-dev
