From 40359ccb836866435b03a0cb57345002b587d875 Mon Sep 17 00:00:00 2001 From: Nathan Scott Date: Thu, 6 Jul 2006 10:03:28 +0200 Subject: [PATCH] [PATCH] blktrace: readahead support Provide the needed kernel support for distinguishing readahead from regular read requests when tracing block devices. Signed-off-by: Nathan Scott Signed-off-by: Jens Axboe --- block/blktrace.c | 5 ++++- include/linux/blktrace_api.h | 1 + 2 files changed, 5 insertions(+), 1 deletion(-) diff --git a/block/blktrace.c b/block/blktrace.c index 92925e7d9e6c..b8c0702777ff 100644 --- a/block/blktrace.c +++ b/block/blktrace.c @@ -69,7 +69,7 @@ static u32 ddir_act[2] __read_mostly = { BLK_TC_ACT(BLK_TC_READ), BLK_TC_ACT(BLK /* * Bio action bits of interest */ -static u32 bio_act[3] __read_mostly = { 0, BLK_TC_ACT(BLK_TC_BARRIER), BLK_TC_ACT(BLK_TC_SYNC) }; +static u32 bio_act[5] __read_mostly = { 0, BLK_TC_ACT(BLK_TC_BARRIER), BLK_TC_ACT(BLK_TC_SYNC), 0, BLK_TC_ACT(BLK_TC_AHEAD) }; /* * More could be added as needed, taking care to increment the decrementer @@ -79,6 +79,8 @@ static u32 bio_act[3] __read_mostly = { 0, BLK_TC_ACT(BLK_TC_BARRIER), BLK_TC_AC (((rw) & (1 << BIO_RW_BARRIER)) >> (BIO_RW_BARRIER - 0)) #define trace_sync_bit(rw) \ (((rw) & (1 << BIO_RW_SYNC)) >> (BIO_RW_SYNC - 1)) +#define trace_ahead_bit(rw) \ + (((rw) & (1 << BIO_RW_AHEAD)) << (BIO_RW_AHEAD - 0)) /* * The worker for the various blk_add_trace*() types. Fills out a @@ -100,6 +102,7 @@ void __blk_add_trace(struct blk_trace *bt, sector_t sector, int bytes, what |= ddir_act[rw & WRITE]; what |= bio_act[trace_barrier_bit(rw)]; what |= bio_act[trace_sync_bit(rw)]; + what |= bio_act[trace_ahead_bit(rw)]; pid = tsk->pid; if (unlikely(act_log_check(bt, what, sector, pid))) diff --git a/include/linux/blktrace_api.h b/include/linux/blktrace_api.h index d95615fc6da5..2346a1db8561 100644 --- a/include/linux/blktrace_api.h +++ b/include/linux/blktrace_api.h @@ -19,6 +19,7 @@ enum blktrace_cat { BLK_TC_FS = 1 << 8, /* fs requests */ BLK_TC_PC = 1 << 9, /* pc requests */ BLK_TC_NOTIFY = 1 << 10, /* special message */ + BLK_TC_AHEAD = 1 << 11, /* readahead */ BLK_TC_END = 1 << 15, /* only 16-bits, reminder */ };