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charset=UTF-8 Content-Transfer-Encoding: 7bit X-Rspamd-Server: rspam03 X-Rspam-User: X-Rspamd-Queue-Id: 899E8A002D X-Stat-Signature: rrrowte76ghmd1wj4j3eqhupsufp8ffr X-HE-Tag: 1729091356-2863 X-HE-Meta: U2FsdGVkX1/7elx2sciZCpQ5ynS48BnqkIT6kNYk04qeDdo5ya1bWdGWof0DIkq3zJNFQZjOVpDTDI2dBuqRnOGOl0em8s7vo9aIgiH8rKWEYuLP1VrZBZMnRaqbfCVdGakJryXu1nZMu6odn6FOt94rvcicO+aZIbuwmAAqwIH4iMK5rBDVarlzZpVel+4R6y5yXHJO8rHJPUJxXoKwEHpgw92XW5g2EISvBhRfWVESCclIRzy/LYQ+2L59dDw3zy3ClsPQmCO0n7fb+GdXXDny0Gdc1dteNh3CmJ599VPZXNTN+Nh3CY1+8TZv9OfEPPcwKYV3AK05O+YqaZ0i0wAOPeUiW9axtVT4wLwuF94DoeWiQD9Yp9u2MH7F/qwGndy+yBO8kl//i0jtZbX9PAKLL3CNJgaZDNymWlpBZiG0l08RQQfdtR38+l1YgRBk/bBf4p3wxvaaCf5YSTc5hPhauqdBPbi9rikIjZlTqg55QZH5IF0yOKR0ok3zmdVT5PHv3tbEWHagHJyIRg7jDCUjKlgUasFZ7s6VagpYVJ2jljMN0B5aaZc/URx+Gtk1+oqp8AK49itlZ3QYyNEW3eWQzSeL3CmA8KRtCd3TUrS7/Q4QMgAClHZ7X5h4FsIw6/3ln8ogZetd2xmpKyWWbUHnv2jzPbNOTiDQsrlIs7Jv067dtfU5bO2K/grb345HgVy5w0rlFnlXcxVw4rviwWGDtW8zsJ3r1KOOGeopbsYDuO1nE4moWffzuV3LxeAnjrxuQ637lf+dWZIkpPlEoNLdEn/Ezy4VIyy+W6YyGpgavuN6+C9y/zHdqn7fXi5/3oP2AOdeUJ+jli3/E7hdcuSc0Ij8dxzgX9x/+XKDtcOPpyImvaTCQh1JkTS75MynDNGfCO1Ac4Fw6p42iQtQjNMH70osrEh+kpxkmLb3nONk6tA5li2bRzPtZmEpzcHsepYh9IbNbo0jT3f5isF w5W+/2MP pNDgaD3im6mo0OCYGT10yW+LfcNJ7RUoWG4+sNUFK6CgHsl//WUDNd4IJGucWf/f2zarJPM+O6nFLn79EwPdcXYGYKUQVIsVqklIFMIxTNpzpYXWel5rmUINQwK5nrHOqHM9hwCq45dNKoRqgYgtg1ZaPmd6sWhVjQEC/D8b+A8x7MLrQIni9RHDSKTjoPeZOO5NoVUxz1UIk28AXCjXC4w8Qt4erTWttEbL90Ji/LQsQinfVGP5DF3koSgdS8XDyc296YN+nTceMzSgThNEN5DAA6Q== X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On 16/10/2024 15:54, Jeff Layton wrote: > On Wed, 2024-10-16 at 10:47 -0400, Chuck Lever wrote: >> On Wed, Oct 16, 2024 at 03:42:12PM +0100, Ryan Roberts wrote: >>> + Chuck Lever, Jeff Layton >>> >>> This was a rather tricky series to get the recipients correct for and my script >>> did not realize that "supporter" was a pseudonym for "maintainer" so you were >>> missed off the original post. Appologies! >>> >>> More context in cover letter: >>> https://lore.kernel.org/all/20241014105514.3206191-1-ryan.roberts@arm.com/ >>> >>> >>> On 14/10/2024 11:58, Ryan Roberts wrote: >>>> To prepare for supporting boot-time page size selection, refactor code >>>> to remove assumptions about PAGE_SIZE being compile-time constant. Code >>>> intended to be equivalent when compile-time page size is active. >>>> >>>> Updated array sizes in various structs to contain enough entries for the >>>> smallest supported page size. >>>> >>>> Signed-off-by: Ryan Roberts >>>> --- >>>> >>>> ***NOTE*** >>>> Any confused maintainers may want to read the cover note here for context: >>>> https://lore.kernel.org/all/20241014105514.3206191-1-ryan.roberts@arm.com/ >>>> >>>> include/linux/sunrpc/svc.h | 8 +++++--- >>>> include/linux/sunrpc/svc_rdma.h | 4 ++-- >>>> include/linux/sunrpc/svcsock.h | 2 +- >>>> 3 files changed, 8 insertions(+), 6 deletions(-) >>>> >>>> diff --git a/include/linux/sunrpc/svc.h b/include/linux/sunrpc/svc.h >>>> index a7d0406b9ef59..dda44018b8f36 100644 >>>> --- a/include/linux/sunrpc/svc.h >>>> +++ b/include/linux/sunrpc/svc.h >>>> @@ -160,6 +160,8 @@ extern u32 svc_max_payload(const struct svc_rqst *rqstp); >>>> */ >>>> #define RPCSVC_MAXPAGES ((RPCSVC_MAXPAYLOAD+PAGE_SIZE-1)/PAGE_SIZE \ >>>> + 2 + 1) >>>> +#define RPCSVC_MAXPAGES_MAX ((RPCSVC_MAXPAYLOAD+PAGE_SIZE_MIN-1)/PAGE_SIZE_MIN \ >>>> + + 2 + 1) >> >> There is already a "MAX" in the name, so adding this new macro seems >> superfluous to me. Can we get away with simply updating the >> "RPCSVC_MAXPAGES" macro, instead of adding this new one? >> > > +1 that was my thinking too. This is mostly just used to size arrays, > so we might as well just change the existing macro. I agree, its not the prettiest. I was (incorrectly) assuming you would want to continue to limit the number of actual pages at runtime based on the in-use page size. That said, looking again at the code, RPCSVC_MAXPAGES never actually gets used to dynamically allocate any memory. So I propose to just do the following: #define RPCSVC_MAXPAGES ((RPCSVC_MAXPAYLOAD+PAGE_SIZE_MIN-1)/ PAGE_SIZE_MIN + 2 + 1) That will be 259 in practice (assuming PAGE_SIZE_MIN=4K). > > With 64k pages we probably wouldn't need arrays as long as these will > be. Fixing those array sizes to be settable at runtime though is not a > trivial project though. Indeed. Hopefully the above is sufficient. Thanks for the review! Ryan > >> >>>> /* >>>> * The context of a single thread, including the request currently being >>>> @@ -190,14 +192,14 @@ struct svc_rqst { >>>> struct xdr_stream rq_res_stream; >>>> struct page *rq_scratch_page; >>>> struct xdr_buf rq_res; >>>> - struct page *rq_pages[RPCSVC_MAXPAGES + 1]; >>>> + struct page *rq_pages[RPCSVC_MAXPAGES_MAX + 1]; >>>> struct page * *rq_respages; /* points into rq_pages */ >>>> struct page * *rq_next_page; /* next reply page to use */ >>>> struct page * *rq_page_end; /* one past the last page */ >>>> >>>> struct folio_batch rq_fbatch; >>>> - struct kvec rq_vec[RPCSVC_MAXPAGES]; /* generally useful.. */ >>>> - struct bio_vec rq_bvec[RPCSVC_MAXPAGES]; >>>> + struct kvec rq_vec[RPCSVC_MAXPAGES_MAX]; /* generally useful.. */ >>>> + struct bio_vec rq_bvec[RPCSVC_MAXPAGES_MAX]; >>>> >>>> __be32 rq_xid; /* transmission id */ >>>> u32 rq_prog; /* program number */ >>>> diff --git a/include/linux/sunrpc/svc_rdma.h b/include/linux/sunrpc/svc_rdma.h >>>> index d33bab33099ab..7c6441e8d6f7a 100644 >>>> --- a/include/linux/sunrpc/svc_rdma.h >>>> +++ b/include/linux/sunrpc/svc_rdma.h >>>> @@ -200,7 +200,7 @@ struct svc_rdma_recv_ctxt { >>>> struct svc_rdma_pcl rc_reply_pcl; >>>> >>>> unsigned int rc_page_count; >>>> - struct page *rc_pages[RPCSVC_MAXPAGES]; >>>> + struct page *rc_pages[RPCSVC_MAXPAGES_MAX]; >>>> }; >>>> >>>> /* >>>> @@ -242,7 +242,7 @@ struct svc_rdma_send_ctxt { >>>> void *sc_xprt_buf; >>>> int sc_page_count; >>>> int sc_cur_sge_no; >>>> - struct page *sc_pages[RPCSVC_MAXPAGES]; >>>> + struct page *sc_pages[RPCSVC_MAXPAGES_MAX]; >>>> struct ib_sge sc_sges[]; >>>> }; >>>> >>>> diff --git a/include/linux/sunrpc/svcsock.h b/include/linux/sunrpc/svcsock.h >>>> index 7c78ec6356b92..6c6bcc82685a3 100644 >>>> --- a/include/linux/sunrpc/svcsock.h >>>> +++ b/include/linux/sunrpc/svcsock.h >>>> @@ -40,7 +40,7 @@ struct svc_sock { >>>> >>>> struct completion sk_handshake_done; >>>> >>>> - struct page * sk_pages[RPCSVC_MAXPAGES]; /* received data */ >>>> + struct page * sk_pages[RPCSVC_MAXPAGES_MAX]; /* received data */ >>>> }; >>>> >>>> static inline u32 svc_sock_reclen(struct svc_sock *svsk) >>> >> >