* [PATCH] ppc: bpf_jit: support MOD operation @ 2013-08-27 22:49 Vladimir Murzin 2013-09-02 17:48 ` Vladimir Murzin 0 siblings, 1 reply; 9+ messages in thread From: Vladimir Murzin @ 2013-08-27 22:49 UTC (permalink / raw) To: linuxppc-dev; +Cc: dborkman, paulus, davem, Vladimir Murzin commit b6069a9570 (filter: add MOD operation) added generic support for modulus operation in BPF. This patch brings JIT support for PPC64 Signed-off-by: Vladimir Murzin <murzin.v@gmail.com> --- arch/powerpc/net/bpf_jit_comp.c | 22 ++++++++++++++++++++++ 1 file changed, 22 insertions(+) diff --git a/arch/powerpc/net/bpf_jit_comp.c b/arch/powerpc/net/bpf_jit_comp.c index bf56e33..96f24dc 100644 --- a/arch/powerpc/net/bpf_jit_comp.c +++ b/arch/powerpc/net/bpf_jit_comp.c @@ -193,6 +193,28 @@ static int bpf_jit_build_body(struct sk_filter *fp, u32 *image, PPC_MUL(r_A, r_A, r_scratch1); } break; + case BPF_S_ALU_MOD_X: /* A %= X; */ + ctx->seen |= SEEN_XREG; + PPC_CMPWI(r_X, 0); + if (ctx->pc_ret0 != -1) { + PPC_BCC(COND_EQ, addrs[ctx->pc_ret0]); + } else { + PPC_BCC_SHORT(COND_NE, (ctx->idx*4)+12); + PPC_LI(r_ret, 0); + PPC_JMP(exit_addr); + } + PPC_DIVWU(r_scratch1, r_A, r_X); + PPC_MUL(r_scratch1, r_X, r_scratch1); + PPC_SUB(r_A, r_A, r_scratch1); + break; + case BPF_S_ALU_MOD_K: /* A %= K; */ +#define r_scratch2 (r_scratch1 + 1) + PPC_LI32(r_scratch2, K); + PPC_DIVWU(r_scratch1, r_A, r_scratch2); + PPC_MUL(r_scratch1, r_scratch2, r_scratch1); + PPC_SUB(r_A, r_A, r_scratch1); +#undef r_scratch2 + break; case BPF_S_ALU_DIV_X: /* A /= X; */ ctx->seen |= SEEN_XREG; PPC_CMPWI(r_X, 0); -- 1.8.1.5 ^ permalink raw reply related [flat|nested] 9+ messages in thread
* Re: [PATCH] ppc: bpf_jit: support MOD operation 2013-08-27 22:49 [PATCH] ppc: bpf_jit: support MOD operation Vladimir Murzin @ 2013-09-02 17:48 ` Vladimir Murzin 2013-09-02 20:45 ` Benjamin Herrenschmidt 0 siblings, 1 reply; 9+ messages in thread From: Vladimir Murzin @ 2013-09-02 17:48 UTC (permalink / raw) To: linuxppc-dev; +Cc: dborkman, paulus, davem Ping On Wed, Aug 28, 2013 at 02:49:52AM +0400, Vladimir Murzin wrote: > commit b6069a9570 (filter: add MOD operation) added generic > support for modulus operation in BPF. > > This patch brings JIT support for PPC64 > > Signed-off-by: Vladimir Murzin <murzin.v@gmail.com> > --- > arch/powerpc/net/bpf_jit_comp.c | 22 ++++++++++++++++++++++ > 1 file changed, 22 insertions(+) > > diff --git a/arch/powerpc/net/bpf_jit_comp.c b/arch/powerpc/net/bpf_jit_comp.c > index bf56e33..96f24dc 100644 > --- a/arch/powerpc/net/bpf_jit_comp.c > +++ b/arch/powerpc/net/bpf_jit_comp.c > @@ -193,6 +193,28 @@ static int bpf_jit_build_body(struct sk_filter *fp, u32 *image, > PPC_MUL(r_A, r_A, r_scratch1); > } > break; > + case BPF_S_ALU_MOD_X: /* A %= X; */ > + ctx->seen |= SEEN_XREG; > + PPC_CMPWI(r_X, 0); > + if (ctx->pc_ret0 != -1) { > + PPC_BCC(COND_EQ, addrs[ctx->pc_ret0]); > + } else { > + PPC_BCC_SHORT(COND_NE, (ctx->idx*4)+12); > + PPC_LI(r_ret, 0); > + PPC_JMP(exit_addr); > + } > + PPC_DIVWU(r_scratch1, r_A, r_X); > + PPC_MUL(r_scratch1, r_X, r_scratch1); > + PPC_SUB(r_A, r_A, r_scratch1); > + break; > + case BPF_S_ALU_MOD_K: /* A %= K; */ > +#define r_scratch2 (r_scratch1 + 1) > + PPC_LI32(r_scratch2, K); > + PPC_DIVWU(r_scratch1, r_A, r_scratch2); > + PPC_MUL(r_scratch1, r_scratch2, r_scratch1); > + PPC_SUB(r_A, r_A, r_scratch1); > +#undef r_scratch2 > + break; > case BPF_S_ALU_DIV_X: /* A /= X; */ > ctx->seen |= SEEN_XREG; > PPC_CMPWI(r_X, 0); > -- > 1.8.1.5 > ^ permalink raw reply [flat|nested] 9+ messages in thread
* Re: [PATCH] ppc: bpf_jit: support MOD operation 2013-09-02 17:48 ` Vladimir Murzin @ 2013-09-02 20:45 ` Benjamin Herrenschmidt 2013-09-03 19:58 ` Vladimir Murzin 2013-09-12 1:18 ` Matt Evans 0 siblings, 2 replies; 9+ messages in thread From: Benjamin Herrenschmidt @ 2013-09-02 20:45 UTC (permalink / raw) To: Vladimir Murzin; +Cc: paulus, dborkman, linuxppc-dev, davem, Matt Evans On Mon, 2013-09-02 at 19:48 +0200, Vladimir Murzin wrote: > Ping > > On Wed, Aug 28, 2013 at 02:49:52AM +0400, Vladimir Murzin wrote: > > commit b6069a9570 (filter: add MOD operation) added generic > > support for modulus operation in BPF. > > Sorry, nobody got a chance to review that yet. Unfortunately Matt doesn't work for us anymore and none of us has experience with the BPF code, so somebody (possibly me) will need to spend a bit of time figuring it out before verifying that is correct. Do you have a test case/suite by any chance ? Ben. > > This patch brings JIT support for PPC64 > > > > Signed-off-by: Vladimir Murzin <murzin.v@gmail.com> > > --- > > arch/powerpc/net/bpf_jit_comp.c | 22 ++++++++++++++++++++++ > > 1 file changed, 22 insertions(+) > > > > diff --git a/arch/powerpc/net/bpf_jit_comp.c b/arch/powerpc/net/bpf_jit_comp.c > > index bf56e33..96f24dc 100644 > > --- a/arch/powerpc/net/bpf_jit_comp.c > > +++ b/arch/powerpc/net/bpf_jit_comp.c > > @@ -193,6 +193,28 @@ static int bpf_jit_build_body(struct sk_filter *fp, u32 *image, > > PPC_MUL(r_A, r_A, r_scratch1); > > } > > break; > > + case BPF_S_ALU_MOD_X: /* A %= X; */ > > + ctx->seen |= SEEN_XREG; > > + PPC_CMPWI(r_X, 0); > > + if (ctx->pc_ret0 != -1) { > > + PPC_BCC(COND_EQ, addrs[ctx->pc_ret0]); > > + } else { > > + PPC_BCC_SHORT(COND_NE, (ctx->idx*4)+12); > > + PPC_LI(r_ret, 0); > > + PPC_JMP(exit_addr); > > + } > > + PPC_DIVWU(r_scratch1, r_A, r_X); > > + PPC_MUL(r_scratch1, r_X, r_scratch1); > > + PPC_SUB(r_A, r_A, r_scratch1); > > + break; > > + case BPF_S_ALU_MOD_K: /* A %= K; */ > > +#define r_scratch2 (r_scratch1 + 1) > > + PPC_LI32(r_scratch2, K); > > + PPC_DIVWU(r_scratch1, r_A, r_scratch2); > > + PPC_MUL(r_scratch1, r_scratch2, r_scratch1); > > + PPC_SUB(r_A, r_A, r_scratch1); > > +#undef r_scratch2 > > + break; > > case BPF_S_ALU_DIV_X: /* A /= X; */ > > ctx->seen |= SEEN_XREG; > > PPC_CMPWI(r_X, 0); > > -- > > 1.8.1.5 > > ^ permalink raw reply [flat|nested] 9+ messages in thread
* Re: [PATCH] ppc: bpf_jit: support MOD operation 2013-09-02 20:45 ` Benjamin Herrenschmidt @ 2013-09-03 19:58 ` Vladimir Murzin 2013-09-03 20:52 ` Daniel Borkmann 2013-09-12 1:18 ` Matt Evans 1 sibling, 1 reply; 9+ messages in thread From: Vladimir Murzin @ 2013-09-03 19:58 UTC (permalink / raw) To: Benjamin Herrenschmidt; +Cc: paulus, dborkman, linuxppc-dev, davem, Matt Evans On Tue, Sep 03, 2013 at 06:45:50AM +1000, Benjamin Herrenschmidt wrote: > On Mon, 2013-09-02 at 19:48 +0200, Vladimir Murzin wrote: > > Ping > > > > On Wed, Aug 28, 2013 at 02:49:52AM +0400, Vladimir Murzin wrote: > > > commit b6069a9570 (filter: add MOD operation) added generic > > > support for modulus operation in BPF. > > > > Sorry, nobody got a chance to review that yet. Unfortunately Matt > doesn't work for us anymore and none of us has experience with the > BPF code, so somebody (possibly me) will need to spend a bit of time > figuring it out before verifying that is correct. > > Do you have a test case/suite by any chance ? > > Ben. > Hi Ben! Thanks for your feedback. This patch is only compile tested. I have no real hardware, but I'll probably bring up qemu ppc64 till end of the week... Meanwhile, I've made simple how-to for testing. You can use it if you wish. It is mainly based on the [1] and rechecked on x86-64. 1. get the tcpdump utility (git clone git://bpf.tcpdump.org/tcpdump) 2. get the libcap library (git clone git://bpf.tcpdump.org/libpcap) 2.1. apply patch for libcap [2] (against libcap-1.3 branch) 2.2. build libcap (./configure && make && ln -s libcap.so.1.3.0 libcap.so) 3. build tcpdump (LDFLAGS="-L/path/to/libcap" ./configure && make) 4. run # ./tcpdump -d "(ip[2:2] - 20) % 5 != 0 && ip[6] & 0x20 = 0x20" (000) ldh [14] (001) jeq #0x800 jt 2 jf 10 (002) ldh [18] (003) sub #20 (004) mod #5 (005) jeq #0x0 jt 10 jf 6 (006) ldb [22] (007) and #0x20 (008) jeq #0x20 jt 9 jf 10 (009) ret #65535 (010) ret #0 to get pseudo code (we are interested the most into line #4) 5. enable bpf jit compiler # echo 2 > /proc/sys/net/core/bpf_jit_enable 6. run ./tcpdump -nv "(ip[2:2] - 20) % 5 != 0 && ip[6] & 0x20 = 0x20" 7. check dmesg for lines starting with (output for x86-64 is provided as an example) [ 3768.329253] flen=11 proglen=99 pass=3 image=ffffffffa003c000 [ 3768.329254] JIT code: ffffffffa003c000: 55 48 89 e5 48 83 ec 60 48 89 5d f8 44 8b 4f 60 [ 3768.329255] JIT code: ffffffffa003c010: 44 2b 4f 64 4c 8b 87 c0 00 00 00 0f b7 47 76 86 [ 3768.329256] JIT code: ffffffffa003c020: c4 3d 00 08 00 00 75 37 be 02 00 00 00 e8 9f 3e [ 3768.329257] JIT code: ffffffffa003c030: 02 e1 83 e8 14 31 d2 b9 05 00 00 00 f7 f1 89 d0 [ 3768.329258] JIT code: ffffffffa003c040: 85 c0 74 1b be 06 00 00 00 e8 9f 3e 02 e1 25 20 [ 3768.329259] JIT code: ffffffffa003c050: 00 00 00 83 f8 20 75 07 b8 ff ff 00 00 eb 02 31 [ 3768.329259] JIT code: ffffffffa003c060: c0 c9 c3 8. make sure generated opcodes (JIT code) implement pseudo code form step 4. Reference [1] http://comments.gmane.org/gmane.linux.network/242456 [2] http://permalink.gmane.org/gmane.network.tcpdump.devel/5973 P.S. I hope net people will corect me if I'm wrong there Cheers Vladimir Murzin > > > This patch brings JIT support for PPC64 > > > > > > Signed-off-by: Vladimir Murzin <murzin.v@gmail.com> > > > --- > > > arch/powerpc/net/bpf_jit_comp.c | 22 ++++++++++++++++++++++ > > > 1 file changed, 22 insertions(+) > > > > > > diff --git a/arch/powerpc/net/bpf_jit_comp.c b/arch/powerpc/net/bpf_jit_comp.c > > > index bf56e33..96f24dc 100644 > > > --- a/arch/powerpc/net/bpf_jit_comp.c > > > +++ b/arch/powerpc/net/bpf_jit_comp.c > > > @@ -193,6 +193,28 @@ static int bpf_jit_build_body(struct sk_filter *fp, u32 *image, > > > PPC_MUL(r_A, r_A, r_scratch1); > > > } > > > break; > > > + case BPF_S_ALU_MOD_X: /* A %= X; */ > > > + ctx->seen |= SEEN_XREG; > > > + PPC_CMPWI(r_X, 0); > > > + if (ctx->pc_ret0 != -1) { > > > + PPC_BCC(COND_EQ, addrs[ctx->pc_ret0]); > > > + } else { > > > + PPC_BCC_SHORT(COND_NE, (ctx->idx*4)+12); > > > + PPC_LI(r_ret, 0); > > > + PPC_JMP(exit_addr); > > > + } > > > + PPC_DIVWU(r_scratch1, r_A, r_X); > > > + PPC_MUL(r_scratch1, r_X, r_scratch1); > > > + PPC_SUB(r_A, r_A, r_scratch1); > > > + break; > > > + case BPF_S_ALU_MOD_K: /* A %= K; */ > > > +#define r_scratch2 (r_scratch1 + 1) > > > + PPC_LI32(r_scratch2, K); > > > + PPC_DIVWU(r_scratch1, r_A, r_scratch2); > > > + PPC_MUL(r_scratch1, r_scratch2, r_scratch1); > > > + PPC_SUB(r_A, r_A, r_scratch1); > > > +#undef r_scratch2 > > > + break; > > > case BPF_S_ALU_DIV_X: /* A /= X; */ > > > ctx->seen |= SEEN_XREG; > > > PPC_CMPWI(r_X, 0); > > > -- > > > 1.8.1.5 > > > > > ^ permalink raw reply [flat|nested] 9+ messages in thread
* Re: [PATCH] ppc: bpf_jit: support MOD operation 2013-09-03 19:58 ` Vladimir Murzin @ 2013-09-03 20:52 ` Daniel Borkmann 2013-09-04 7:04 ` Daniel Borkmann 0 siblings, 1 reply; 9+ messages in thread From: Daniel Borkmann @ 2013-09-03 20:52 UTC (permalink / raw) To: Vladimir Murzin; +Cc: Matt Evans, paulus, netdev, linuxppc-dev, davem On 09/03/2013 09:58 PM, Vladimir Murzin wrote: > On Tue, Sep 03, 2013 at 06:45:50AM +1000, Benjamin Herrenschmidt wrote: >> On Mon, 2013-09-02 at 19:48 +0200, Vladimir Murzin wrote: >>> Ping >>> >>> On Wed, Aug 28, 2013 at 02:49:52AM +0400, Vladimir Murzin wrote: >>>> commit b6069a9570 (filter: add MOD operation) added generic >>>> support for modulus operation in BPF. >>>> >> Sorry, nobody got a chance to review that yet. Unfortunately Matt >> doesn't work for us anymore and none of us has experience with the >> BPF code, so somebody (possibly me) will need to spend a bit of time >> figuring it out before verifying that is correct. >> >> Do you have a test case/suite by any chance ? >> >> Ben. >> > > Hi Ben! > > Thanks for your feedback. > > This patch is only compile tested. I have no real hardware, but I'll > probably bring up qemu ppc64 till end of the week... > Meanwhile, I've made simple how-to for testing. You can use it if you wish. > It is mainly based on the [1] and rechecked on x86-64. Please also cc netdev on BPF related changes. Actually, your test plan can be further simplified ... For retrieving and disassembling the JIT image, we have bpf_jit_disasm [1]. 1) echo 2 > /proc/sys/net/core/bpf_jit_enable 2) ... attach filter ... 3) bpf_jit_disasm -o For generating a simple stupid test filter, you can use bpfc [2] (also see its man page). E.g. ... # cat blub ldi #10 mod #8 ret a # bpfc blub { 0x0, 0, 0, 0x0000000a }, { 0x94, 0, 0, 0x00000008 }, { 0x16, 0, 0, 0x00000000 }, And load this array e.g. either into a small C program that attaches this as BPF filter, or simply do bpfc blub > blub2 and run netsniff-ng -f blub2\ -s -i eth0, that should also do it. Then, when attached, the kernel should truncate incoming frames for pf_packet into max length of 2, just as an example. [1] kernel tree, tools/net/bpf_jit_disasm.c [2] git clone git://github.com/borkmann/netsniff-ng.git > 1. get the tcpdump utility (git clone git://bpf.tcpdump.org/tcpdump) > 2. get the libcap library (git clone git://bpf.tcpdump.org/libpcap) > 2.1. apply patch for libcap [2] (against libcap-1.3 branch) > 2.2. build libcap (./configure && make && ln -s libcap.so.1.3.0 libcap.so) > 3. build tcpdump (LDFLAGS="-L/path/to/libcap" ./configure && make) > 4. run > > # ./tcpdump -d "(ip[2:2] - 20) % 5 != 0 && ip[6] & 0x20 = 0x20" > (000) ldh [14] > (001) jeq #0x800 jt 2 jf 10 > (002) ldh [18] > (003) sub #20 > (004) mod #5 > (005) jeq #0x0 jt 10 jf 6 > (006) ldb [22] > (007) and #0x20 > (008) jeq #0x20 jt 9 jf 10 > (009) ret #65535 > (010) ret #0 > > to get pseudo code (we are interested the most into line #4) > > 5. enable bpf jit compiler > > # echo 2 > /proc/sys/net/core/bpf_jit_enable > > 6. run > > ./tcpdump -nv "(ip[2:2] - 20) % 5 != 0 && ip[6] & 0x20 = 0x20" > > 7. check dmesg for lines starting with (output for x86-64 is provided as an example) > > [ 3768.329253] flen=11 proglen=99 pass=3 image=ffffffffa003c000 > [ 3768.329254] JIT code: ffffffffa003c000: 55 48 89 e5 48 83 ec 60 48 89 5d f8 44 8b 4f 60 > [ 3768.329255] JIT code: ffffffffa003c010: 44 2b 4f 64 4c 8b 87 c0 00 00 00 0f b7 47 76 86 > [ 3768.329256] JIT code: ffffffffa003c020: c4 3d 00 08 00 00 75 37 be 02 00 00 00 e8 9f 3e > [ 3768.329257] JIT code: ffffffffa003c030: 02 e1 83 e8 14 31 d2 b9 05 00 00 00 f7 f1 89 d0 > [ 3768.329258] JIT code: ffffffffa003c040: 85 c0 74 1b be 06 00 00 00 e8 9f 3e 02 e1 25 20 > [ 3768.329259] JIT code: ffffffffa003c050: 00 00 00 83 f8 20 75 07 b8 ff ff 00 00 eb 02 31 > [ 3768.329259] JIT code: ffffffffa003c060: c0 c9 c3 > > 8. make sure generated opcodes (JIT code) implement pseudo code form step 4. > > Reference > [1] http://comments.gmane.org/gmane.linux.network/242456 > [2] http://permalink.gmane.org/gmane.network.tcpdump.devel/5973 > > P.S. > I hope net people will corect me if I'm wrong there > > Cheers > Vladimir Murzin > >>>> This patch brings JIT support for PPC64 >>>> >>>> Signed-off-by: Vladimir Murzin <murzin.v@gmail.com> ^ permalink raw reply [flat|nested] 9+ messages in thread
* Re: [PATCH] ppc: bpf_jit: support MOD operation 2013-09-03 20:52 ` Daniel Borkmann @ 2013-09-04 7:04 ` Daniel Borkmann 2013-09-11 16:15 ` Vladimir Murzin 0 siblings, 1 reply; 9+ messages in thread From: Daniel Borkmann @ 2013-09-04 7:04 UTC (permalink / raw) To: Vladimir Murzin; +Cc: Matt Evans, paulus, netdev, linuxppc-dev, davem On 09/03/2013 10:52 PM, Daniel Borkmann wrote: > On 09/03/2013 09:58 PM, Vladimir Murzin wrote: [...] >>> Do you have a test case/suite by any chance ? >>> >>> Ben. >>> >> >> Hi Ben! >> >> Thanks for your feedback. >> >> This patch is only compile tested. I have no real hardware, but I'll >> probably bring up qemu ppc64 till end of the week... >> Meanwhile, I've made simple how-to for testing. You can use it if you wish. >> It is mainly based on the [1] and rechecked on x86-64. > > Please also cc netdev on BPF related changes. > > Actually, your test plan can be further simplified ... > > For retrieving and disassembling the JIT image, we have bpf_jit_disasm [1]. > > 1) echo 2 > /proc/sys/net/core/bpf_jit_enable > 2) ... attach filter ... > 3) bpf_jit_disasm -o > > For generating a simple stupid test filter, you can use bpfc [2] (also > see its man page). E.g. ... > > # cat blub > ldi #10 > mod #8 > ret a > # bpfc blub > { 0x0, 0, 0, 0x0000000a }, > { 0x94, 0, 0, 0x00000008 }, > { 0x16, 0, 0, 0x00000000 }, Plus something like ... ldxi #0 mod x ret a For longer-term testing, also trinity has BPF support. ;) > And load this array e.g. either into a small C program that attaches this > as BPF filter, or simply do bpfc blub > blub2 and run netsniff-ng -f blub2\ > -s -i eth0, that should also do it. > > Then, when attached, the kernel should truncate incoming frames for pf_packet > into max length of 2, just as an example. > > [1] kernel tree, tools/net/bpf_jit_disasm.c > [2] git clone git://github.com/borkmann/netsniff-ng.git ^ permalink raw reply [flat|nested] 9+ messages in thread
* Re: [PATCH] ppc: bpf_jit: support MOD operation 2013-09-04 7:04 ` Daniel Borkmann @ 2013-09-11 16:15 ` Vladimir Murzin 0 siblings, 0 replies; 9+ messages in thread From: Vladimir Murzin @ 2013-09-11 16:15 UTC (permalink / raw) To: Daniel Borkmann; +Cc: Matt Evans, paulus, netdev, linuxppc-dev, davem On Wed, Sep 04, 2013 at 09:04:04AM +0200, Daniel Borkmann wrote: > On 09/03/2013 10:52 PM, Daniel Borkmann wrote: > > On 09/03/2013 09:58 PM, Vladimir Murzin wrote: > [...] > >>> Do you have a test case/suite by any chance ? > >>> > >>> Ben. > >>> > >> > >> Hi Ben! > >> > >> Thanks for your feedback. > >> > >> This patch is only compile tested. I have no real hardware, but I'll > >> probably bring up qemu ppc64 till end of the week... > >> Meanwhile, I've made simple how-to for testing. You can use it if you wish. > >> It is mainly based on the [1] and rechecked on x86-64. Finally I've managed to bring up qemu ppc64 and done simple testing. As a result I could see difference in opcodes for divide instruction - I've just sent the patch for that. WRT mod instruction result is: For BPF program (000) ldh [12] (001) jeq #0x800 jt 2 jf 10 (002) ldh [16] (003) sub #20 (004) mod #5 (005) jeq #0x0 jt 10 jf 6 (006) ldb [20] (007) and #0x20 (008) jeq #0x20 jt 9 jf 10 (009) ret #65535 (010) ret #0 The following code is generated (with patch divw to divwu applied) 244 bytes emitted from JIT compiler (pass:3, flen:11) d0000000015c0018 + <x>: 0: mflr r0 4: std r0,16(r1) 8: std r14,-144(r1) c: std r15,-136(r1) 10: stdu r1,-288(r1) 14: lwz r7,108(r3) 18: lwz r15,104(r3) 1c: subf r15,r7,r15 20: ld r14,216(r3) 24: lis r7,-16384 28: rldicr r7,r7,32,31 2c: oris r7,r7,9 30: ori r7,r7,43428 34: mtlr r7 38: li r6,12 3c: blrl 40: blt- 0x00000000000000dc 44: nop 48: cmplwi r4,2048 4c: bne- 0x00000000000000d8 50: nop 54: lis r7,-16384 58: rldicr r7,r7,32,31 5c: oris r7,r7,9 60: ori r7,r7,43428 64: mtlr r7 68: li r6,16 6c: blrl 70: blt- 0x00000000000000dc 74: nop 78: addi r4,r4,-20 7c: li r8,5 80: divwu r7,r4,r8 84: mullw r7,r8,r7 88: subf r4,r7,r4 8c: cmplwi r4,0 90: beq- 0x00000000000000d8 94: nop 98: lis r7,-16384 9c: rldicr r7,r7,32,31 a0: oris r7,r7,9 a4: ori r7,r7,43456 a8: mtlr r7 ac: li r6,20 b0: blrl b4: blt- 0x00000000000000dc b8: nop bc: andi. r4,r4,32 c0: cmplwi r4,32 c4: bne- 0x00000000000000d8 c8: nop cc: li r3,-1 d0: addis r3,r3,1 d4: b 0x00000000000000dc d8: li r3,0 dc: addi r1,r1,288 e0: ld r0,16(r1) e4: mtlr r0 e8: ld r14,-144(r1) ec: ld r15,-136(r1) f0: blr Raw codes are flen=11 proglen=244 pass=3 image=d0000000015c0018 JIT code: 00000000: 7c 08 02 a6 f8 01 00 10 f9 c1 ff 70 f9 e1 ff 78 JIT code: 00000010: f8 21 fe e1 80 e3 00 6c 81 e3 00 68 7d e7 78 50 JIT code: 00000020: e9 c3 00 d8 3c e0 c0 00 78 e7 07 c6 64 e7 00 09 JIT code: 00000030: 60 e7 a9 a4 7c e8 03 a6 38 c0 00 0c 4e 80 00 21 JIT code: 00000040: 41 80 00 9c 60 00 00 00 28 04 08 00 40 82 00 8c JIT code: 00000050: 60 00 00 00 3c e0 c0 00 78 e7 07 c6 64 e7 00 09 JIT code: 00000060: 60 e7 a9 a4 7c e8 03 a6 38 c0 00 10 4e 80 00 21 JIT code: 00000070: 41 80 00 6c 60 00 00 00 38 84 ff ec 39 00 00 05 JIT code: 00000080: 7c e4 43 96 7c e8 39 d6 7c 87 20 50 28 04 00 00 JIT code: 00000090: 41 82 00 48 60 00 00 00 3c e0 c0 00 78 e7 07 c6 JIT code: 000000a0: 64 e7 00 09 60 e7 a9 c0 7c e8 03 a6 38 c0 00 14 JIT code: 000000b0: 4e 80 00 21 41 80 00 28 60 00 00 00 70 84 00 20 JIT code: 000000c0: 28 04 00 20 40 82 00 14 60 00 00 00 38 60 ff ff JIT code: 000000d0: 3c 63 00 01 48 00 00 08 38 60 00 00 38 21 01 20 JIT code: 000000e0: e8 01 00 10 7c 08 03 a6 e9 c1 ff 70 e9 e1 ff 78 JIT code: 000000f0: 4e 80 00 20 Ben, How do you feel about it? > > > > Please also cc netdev on BPF related changes. > > > > Actually, your test plan can be further simplified ... > > > > For retrieving and disassembling the JIT image, we have bpf_jit_disasm [1]. > > > > 1) echo 2 > /proc/sys/net/core/bpf_jit_enable > > 2) ... attach filter ... > > 3) bpf_jit_disasm -o > > > > For generating a simple stupid test filter, you can use bpfc [2] (also > > see its man page). E.g. ... > > > > # cat blub > > ldi #10 > > mod #8 > > ret a > > # bpfc blub > > { 0x0, 0, 0, 0x0000000a }, > > { 0x94, 0, 0, 0x00000008 }, > > { 0x16, 0, 0, 0x00000000 }, > > Plus something like ... > > ldxi #0 > mod x > ret a > Thanks Daniel! Unfortunately, I couldn't trigger JIT compiler with the pair bpfc/netsniff-ng (even for x86-64). I guess I missed something. I'd be very grateful if you point at my mistakes. > For longer-term testing, also trinity has BPF support. ;) > Wow! Could do give some hint how to run this for BPF only? > > And load this array e.g. either into a small C program that attaches this > > as BPF filter, or simply do bpfc blub > blub2 and run netsniff-ng -f blub2\ > > -s -i eth0, that should also do it. > > > > Then, when attached, the kernel should truncate incoming frames for pf_packet > > into max length of 2, just as an example. > > > > [1] kernel tree, tools/net/bpf_jit_disasm.c > > [2] git clone git://github.com/borkmann/netsniff-ng.git Thanks Vladimir ^ permalink raw reply [flat|nested] 9+ messages in thread
* Re: [PATCH] ppc: bpf_jit: support MOD operation 2013-09-02 20:45 ` Benjamin Herrenschmidt 2013-09-03 19:58 ` Vladimir Murzin @ 2013-09-12 1:18 ` Matt Evans 2013-09-12 2:56 ` Vladimir Murzin 1 sibling, 1 reply; 9+ messages in thread From: Matt Evans @ 2013-09-12 1:18 UTC (permalink / raw) To: Benjamin Herrenschmidt Cc: paulus, Vladimir Murzin, linuxppc-dev, davem, dborkman Hi Ben, Vladimir, *dusts off very thick PPC cobwebs* Sorry for the delay as I'm = travelling, didn't get to this until now. On 02/09/2013, at 9:45 PM, Benjamin Herrenschmidt wrote: > On Mon, 2013-09-02 at 19:48 +0200, Vladimir Murzin wrote: >> Ping >>=20 >> On Wed, Aug 28, 2013 at 02:49:52AM +0400, Vladimir Murzin wrote: >>> commit b6069a9570 (filter: add MOD operation) added generic >>> support for modulus operation in BPF. >>>=20 > Sorry, nobody got a chance to review that yet. Unfortunately Matt > doesn't work for us anymore and none of us has experience with the > BPF code, so somebody (possibly me) will need to spend a bit of time > figuring it out before verifying that is correct. >=20 > Do you have a test case/suite by any chance ? >=20 > Ben. >=20 >>> This patch brings JIT support for PPC64 >>>=20 >>> Signed-off-by: Vladimir Murzin <murzin.v@gmail.com> >>> --- >>> arch/powerpc/net/bpf_jit_comp.c | 22 ++++++++++++++++++++++ >>> 1 file changed, 22 insertions(+) >>>=20 >>> diff --git a/arch/powerpc/net/bpf_jit_comp.c = b/arch/powerpc/net/bpf_jit_comp.c >>> index bf56e33..96f24dc 100644 >>> --- a/arch/powerpc/net/bpf_jit_comp.c >>> +++ b/arch/powerpc/net/bpf_jit_comp.c >>> @@ -193,6 +193,28 @@ static int bpf_jit_build_body(struct sk_filter = *fp, u32 *image, >>> PPC_MUL(r_A, r_A, r_scratch1); >>> } >>> break; >>> + case BPF_S_ALU_MOD_X: /* A %=3D X; */ >>> + ctx->seen |=3D SEEN_XREG; >>> + PPC_CMPWI(r_X, 0); >>> + if (ctx->pc_ret0 !=3D -1) { >>> + PPC_BCC(COND_EQ, addrs[ctx->pc_ret0]); >>> + } else { >>> + PPC_BCC_SHORT(COND_NE, (ctx->idx*4)+12); >>> + PPC_LI(r_ret, 0); >>> + PPC_JMP(exit_addr); >>> + } >>> + PPC_DIVWU(r_scratch1, r_A, r_X); >>> + PPC_MUL(r_scratch1, r_X, r_scratch1); >>> + PPC_SUB(r_A, r_A, r_scratch1); >>> + break; Without having compiled & tested this, it looks fine to me (especially = with the corrected DIVWU opcode in the other patch, oops...). >>> + case BPF_S_ALU_MOD_K: /* A %=3D K; */ >>> +#define r_scratch2 (r_scratch1 + 1) >>> + PPC_LI32(r_scratch2, K); >>> + PPC_DIVWU(r_scratch1, r_A, r_scratch2); >>> + PPC_MUL(r_scratch1, r_scratch2, r_scratch1); >>> + PPC_SUB(r_A, r_A, r_scratch1); >>> +#undef r_scratch2 >>> + break; If you need another scratch register, it should really be defined in = bpf_jit.h instead. Once you define r_scratch2 in there, Acked-by: Matt Evans <matt@ozlabs.org> Thanks! Matt >>> case BPF_S_ALU_DIV_X: /* A /=3D X; */ >>> ctx->seen |=3D SEEN_XREG; >>> PPC_CMPWI(r_X, 0); >>> --=20 >>> 1.8.1.5 >>>=20 >=20 ^ permalink raw reply [flat|nested] 9+ messages in thread
* Re: [PATCH] ppc: bpf_jit: support MOD operation 2013-09-12 1:18 ` Matt Evans @ 2013-09-12 2:56 ` Vladimir Murzin 0 siblings, 0 replies; 9+ messages in thread From: Vladimir Murzin @ 2013-09-12 2:56 UTC (permalink / raw) To: Matt Evans; +Cc: dborkman, linuxppc-dev, davem, paulus On Thu, Sep 12, 2013 at 02:18:37AM +0100, Matt Evans wrote: > Hi Ben, Vladimir, > > > *dusts off very thick PPC cobwebs* Sorry for the delay as I'm travelling, didn't get to this until now. > > On 02/09/2013, at 9:45 PM, Benjamin Herrenschmidt wrote: > > > On Mon, 2013-09-02 at 19:48 +0200, Vladimir Murzin wrote: > >> Ping > >> > >> On Wed, Aug 28, 2013 at 02:49:52AM +0400, Vladimir Murzin wrote: > >>> commit b6069a9570 (filter: add MOD operation) added generic > >>> support for modulus operation in BPF. > >>> > > Sorry, nobody got a chance to review that yet. Unfortunately Matt > > doesn't work for us anymore and none of us has experience with the > > BPF code, so somebody (possibly me) will need to spend a bit of time > > figuring it out before verifying that is correct. > > > > Do you have a test case/suite by any chance ? > > > > Ben. > > > >>> This patch brings JIT support for PPC64 > >>> > >>> Signed-off-by: Vladimir Murzin <murzin.v@gmail.com> > >>> --- > >>> arch/powerpc/net/bpf_jit_comp.c | 22 ++++++++++++++++++++++ > >>> 1 file changed, 22 insertions(+) > >>> > >>> diff --git a/arch/powerpc/net/bpf_jit_comp.c b/arch/powerpc/net/bpf_jit_comp.c > >>> index bf56e33..96f24dc 100644 > >>> --- a/arch/powerpc/net/bpf_jit_comp.c > >>> +++ b/arch/powerpc/net/bpf_jit_comp.c > >>> @@ -193,6 +193,28 @@ static int bpf_jit_build_body(struct sk_filter *fp, u32 *image, > >>> PPC_MUL(r_A, r_A, r_scratch1); > >>> } > >>> break; > >>> + case BPF_S_ALU_MOD_X: /* A %= X; */ > >>> + ctx->seen |= SEEN_XREG; > >>> + PPC_CMPWI(r_X, 0); > >>> + if (ctx->pc_ret0 != -1) { > >>> + PPC_BCC(COND_EQ, addrs[ctx->pc_ret0]); > >>> + } else { > >>> + PPC_BCC_SHORT(COND_NE, (ctx->idx*4)+12); > >>> + PPC_LI(r_ret, 0); > >>> + PPC_JMP(exit_addr); > >>> + } > >>> + PPC_DIVWU(r_scratch1, r_A, r_X); > >>> + PPC_MUL(r_scratch1, r_X, r_scratch1); > >>> + PPC_SUB(r_A, r_A, r_scratch1); > >>> + break; > > Without having compiled & tested this, it looks fine to me (especially with the corrected DIVWU opcode in the other patch, oops...). > > >>> + case BPF_S_ALU_MOD_K: /* A %= K; */ > >>> +#define r_scratch2 (r_scratch1 + 1) > >>> + PPC_LI32(r_scratch2, K); > >>> + PPC_DIVWU(r_scratch1, r_A, r_scratch2); > >>> + PPC_MUL(r_scratch1, r_scratch2, r_scratch1); > >>> + PPC_SUB(r_A, r_A, r_scratch1); > >>> +#undef r_scratch2 > >>> + break; > > If you need another scratch register, it should really be defined in bpf_jit.h instead. > > Once you define r_scratch2 in there, > > Acked-by: Matt Evans <matt@ozlabs.org> > > > Thanks! > > > Matt > Thanks! Vladimir > > > > >>> case BPF_S_ALU_DIV_X: /* A /= X; */ > >>> ctx->seen |= SEEN_XREG; > >>> PPC_CMPWI(r_X, 0); > >>> -- > >>> 1.8.1.5 > >>> > > > ^ permalink raw reply [flat|nested] 9+ messages in thread
end of thread, other threads:[~2013-09-12 2:56 UTC | newest] Thread overview: 9+ messages (download: mbox.gz / follow: Atom feed) -- links below jump to the message on this page -- 2013-08-27 22:49 [PATCH] ppc: bpf_jit: support MOD operation Vladimir Murzin 2013-09-02 17:48 ` Vladimir Murzin 2013-09-02 20:45 ` Benjamin Herrenschmidt 2013-09-03 19:58 ` Vladimir Murzin 2013-09-03 20:52 ` Daniel Borkmann 2013-09-04 7:04 ` Daniel Borkmann 2013-09-11 16:15 ` Vladimir Murzin 2013-09-12 1:18 ` Matt Evans 2013-09-12 2:56 ` Vladimir Murzin
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